From 4ff0a7276500c903556a4694c0218e60cc12ccbd Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Fri, 9 Jul 2021 17:00:15 -0300
Subject: [PATCH 01/52] Add CS423x EEPROM persistence

---
 src/sound/snd_cs423x.c | 40 ++++++++++++++++++++++++++++++++++++----
 1 file changed, 36 insertions(+), 4 deletions(-)

diff --git a/src/sound/snd_cs423x.c b/src/sound/snd_cs423x.c
index 0f70c2f8d..7ea1deb65 100644
--- a/src/sound/snd_cs423x.c
+++ b/src/sound/snd_cs423x.c
@@ -34,6 +34,7 @@
 #include <86box/snd_ad1848.h>
 #include <86box/snd_opl.h>
 #include <86box/snd_sb.h>
+#include <86box/nvr.h>
 
 
 enum {
@@ -135,6 +136,7 @@ typedef struct cs423x_t
     uint16_t	wss_base, opl_base, sb_base, ctrl_base, ram_addr, eeprom_size: 11;
     uint8_t	type, ad1848_type, pnp_offset, regs[8], indirect_regs[16],
 		eeprom_data[2048], ram_data[384], ram_dl: 2, opl_wss: 1;
+    char	*nvr_path;
 
     uint8_t	pnp_enable: 1, key_pos: 5, slam_enable: 1, slam_state: 2, slam_ld, slam_reg;
     isapnp_device_config_t *slam_config;
@@ -146,6 +148,20 @@ static void	cs423x_pnp_enable(cs423x_t *dev, uint8_t update_rom, uint8_t update_
 static void	cs423x_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *priv);
 
 
+static void
+cs423x_nvram(cs423x_t *dev, uint8_t save)
+{
+    FILE *f = nvr_fopen(dev->nvr_path, save ? "wb" : "rb");
+    if (f) {
+	if (save)
+		fwrite(dev->eeprom_data, sizeof(dev->eeprom_data), 1, f);
+	else
+		fread(dev->eeprom_data, sizeof(dev->eeprom_data), 1, f);
+	fclose(f);
+    }
+}
+
+
 static uint8_t
 cs423x_read(uint16_t addr, void *priv)
 {
@@ -678,10 +694,14 @@ cs423x_reset(void *priv)
     cs423x_t *dev = (cs423x_t *) priv;
 
     /* Load EEPROM data to RAM, or just clear RAM if there's no EEPROM. */
-    if (dev->eeprom)
+    if (dev->eeprom) {
 	memcpy(dev->ram_data, &dev->eeprom_data[4], MIN(sizeof(dev->ram_data), sizeof(dev->eeprom_data) - 4));
-    else
+
+	/* Save EEPROM contents to file. */
+	cs423x_nvram(dev, 1);
+    } else {
 	memset(dev->ram_data, 0, sizeof(dev->ram_data));
+    }
 
     /* Reset registers. */
     memset(dev->indirect_regs, 0, sizeof(dev->indirect_regs));
@@ -729,17 +749,26 @@ cs423x_init(const device_t *info)
 		dev->eeprom_data[2] = sizeof(cs4236b_eeprom) >> 8;
 		dev->eeprom_data[3] = sizeof(cs4236b_eeprom) & 0xff;
 
-		/* Set PnP card ID. */
+		/* Set PnP card ID and EEPROM file name. */
 		switch (dev->type) {
+			case CRYSTAL_CS4236B:
+				dev->nvr_path = "cs4236b.nvr";
+				break;
+
 			case CRYSTAL_CS4237B:
 				dev->eeprom_data[26] = 0x37;
+				dev->nvr_path = "cs4237b.nvr";
 				break;
 
 			case CRYSTAL_CS4238B:
 				dev->eeprom_data[26] = 0x38;
+				dev->nvr_path = "cs4238b.nvr";
 				break;
 		}
 
+		/* Load EEPROM contents from file if present. */
+		cs423x_nvram(dev, 0);
+
 		/* Initialize game port. The '7B and '8B game port only responds to 6 I/O ports; the remaining
 		   2 ports are reserved on those chips, and probably connected to the Digital Assist feature. */
 		dev->gameport = gameport_add((dev->type == CRYSTAL_CS4236B) ? &gameport_pnp_device : &gameport_pnp_6io_device);
@@ -774,8 +803,11 @@ cs423x_close(void *priv)
 {
     cs423x_t *dev = (cs423x_t *) priv;
 
-    if (dev->eeprom)
+    /* Save EEPROM contents to file. */
+    if (dev->eeprom) {
+	cs423x_nvram(dev, 1);
 	i2c_eeprom_close(dev->eeprom);
+    }
 
     i2c_gpio_close(dev->i2c);
 

From ee253ad0e98f62bd354a45e6805ecf987a1e8f43 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Fri, 9 Jul 2021 17:01:12 -0300
Subject: [PATCH 02/52] Remove TRC reset workaround from ICS9xxx

---
 src/device/clock_ics9xxx.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/device/clock_ics9xxx.c b/src/device/clock_ics9xxx.c
index ddca7712b..df7aaf5fa 100644
--- a/src/device/clock_ics9xxx.c
+++ b/src/device/clock_ics9xxx.c
@@ -1280,13 +1280,11 @@ ics9xxx_get(uint8_t model)
 
     dev->name = "ICS9xxx-xx Clock Generator";
     dev->local = model;
+    dev->flags = DEVICE_ISA;
 #ifdef ENABLE_ICS9xxx_DETECT
-    if (model == ICS9xxx_xx) {
-	dev->flags = DEVICE_PCI;
+    if (model == ICS9xxx_xx)
 	dev->reset = ics9xxx_detect_reset;
-    } else
 #endif
-	dev->flags = DEVICE_ISA;
     dev->init = ics9xxx_init;
     dev->close = ics9xxx_close;
 

From b9c68bf277af8d7167900d57fb8580819ecac105 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 11 Jul 2021 16:58:52 -0300
Subject: [PATCH 03/52] Initial commit for AC97

---
 src/chipset/via_pipc.c       | 206 +++++++++--
 src/device/hasp.c            |   3 +-
 src/game/gameport.c          |   2 +-
 src/include/86box/device.h   |   3 +-
 src/include/86box/snd_ac97.h |  49 +++
 src/machine/m_at_socket370.c |   7 +-
 src/machine/machine_table.c  |   2 +-
 src/pci.c                    |   2 +-
 src/sound/CMakeLists.txt     |   2 +-
 src/sound/snd_ac97_codec.c   | 227 +++++++++++++
 src/sound/snd_ac97_via.c     | 638 +++++++++++++++++++++++++++++++++++
 src/sound/snd_cs423x.c       |   2 +-
 src/win/Makefile.mingw       |   1 +
 13 files changed, 1115 insertions(+), 29 deletions(-)
 create mode 100644 src/include/86box/snd_ac97.h
 create mode 100644 src/sound/snd_ac97_codec.c
 create mode 100644 src/sound/snd_ac97_via.c

diff --git a/src/chipset/via_pipc.c b/src/chipset/via_pipc.c
index 46d2f8597..9ad32deca 100644
--- a/src/chipset/via_pipc.c
+++ b/src/chipset/via_pipc.c
@@ -49,6 +49,8 @@
 #include <86box/chipset.h>
 #include <86box/sio.h>
 #include <86box/hwm.h>
+#include <86box/gameport.h>
+#include <86box/snd_ac97.h>
 
 /* Most revision numbers (PCI-ISA bridge or otherwise) were lifted from PCI device
    listings on forums, as VIA's datasheets are not very helpful regarding those. */
@@ -77,6 +79,8 @@ typedef struct
     smbus_piix4_t *smbus;
     usb_t	*usb[2];
     acpi_t	*acpi;
+    void	*gameport, *ac97;
+    uint16_t	midigame_base;
 } pipc_t;
 
 
@@ -100,6 +104,13 @@ pipc_log(const char *fmt, ...)
 #endif
 
 
+static void	pipc_sgd_handlers(pipc_t *dev, uint8_t modem);
+static void	pipc_midigame_handlers(pipc_t *dev, uint8_t modem);
+static void	pipc_codec_handlers(pipc_t *dev, uint8_t modem);
+static uint8_t	pipc_read(int func, int addr, void *priv);
+static void	pipc_write(int func, int addr, uint8_t val, void *priv);
+
+
 static void
 pipc_reset_hard(void *priv)
 {
@@ -332,19 +343,29 @@ pipc_reset_hard(void *priv)
 		}
 
 		dev->ac97_regs[i][0x10] = 0x01;
-		dev->ac97_regs[i][(dev->local >= VIA_PIPC_8231) ? 0x1c : 0x14] = 0x01;
-
-		if ((i == 0) && (dev->local >= VIA_PIPC_8231)) {
-			dev->ac97_regs[i][0x18] = 0x31;
-			dev->ac97_regs[i][0x19] = 0x03;
+		if (i == 0) {
+			dev->ac97_regs[i][0x14] = 0x01;
+			dev->ac97_regs[i][0x18] = 0x01;
 		}
+		dev->ac97_regs[i][0x1c] = 0x01;
 
 		dev->ac97_regs[i][0x3d] = 0x03;
 
+		if (i == 0)
+			dev->ac97_regs[i][0x40] = 0x01;
+
 		dev->ac97_regs[i][0x43] = 0x1c;
+		dev->ac97_regs[i][0x4b] = 0x02;
+
+		pipc_sgd_handlers(dev, i);
+		pipc_midigame_handlers(dev, i);
+		pipc_codec_handlers(dev, i);
 	}
     }
 
+    if (dev->gameport)
+	gameport_remap(dev->gameport, 0x200);
+
     pci_set_irq_routing(PCI_INTA, PCI_IRQ_DISABLED);
     pci_set_irq_routing(PCI_INTB, PCI_IRQ_DISABLED);
     pci_set_irq_routing(PCI_INTC, PCI_IRQ_DISABLED);
@@ -428,6 +449,79 @@ pipc_bus_master_handlers(pipc_t *dev)
 }
 
 
+static void
+pipc_sgd_handlers(pipc_t *dev, uint8_t modem)
+{
+    if (!dev->ac97)
+    	return;
+
+    if (modem)
+    	ac97_via_remap_modem_sgd(dev->ac97, dev->ac97_regs[1][0x11] << 8, dev->ac97_regs[1][0x04] & PCI_COMMAND_IO);
+    else
+    	ac97_via_remap_audio_sgd(dev->ac97, dev->ac97_regs[0][0x11] << 8, dev->ac97_regs[0][0x04] & PCI_COMMAND_IO);
+}
+
+
+static uint8_t
+pipc_midigame_read(uint16_t addr, void *priv)
+{
+    pipc_t *dev = (pipc_t *) priv;
+    uint8_t ret = 0xff;
+
+    addr &= 0x03;
+    switch (addr) {
+	case 0x02: case 0x03:
+		ret = pipc_read(5, 0x48 + addr, dev);
+		break;
+    }
+
+    return ret;
+}
+
+
+static void
+pipc_midigame_write(uint16_t addr, uint8_t val, void *priv)
+{
+    pipc_t *dev = (pipc_t *) priv;
+
+    addr &= 0x03;
+    switch (addr) {
+	case 0x02: case 0x03:
+		pipc_write(5, 0x48 + addr, val, dev);
+		break;
+    }
+}
+
+
+static void
+pipc_midigame_handlers(pipc_t *dev, uint8_t modem)
+{
+    if (!dev->ac97 || modem)
+	return;
+
+    if (dev->midigame_base)
+	io_removehandler(dev->midigame_base, 4, pipc_midigame_read, NULL, NULL, pipc_midigame_write, NULL, NULL, dev);
+
+    dev->midigame_base = (dev->ac97_regs[0][0x19] << 8) | (dev->ac97_regs[0][0x18] & 0xfc);
+
+    if (dev->midigame_base && (dev->ac97_regs[0][0x04] & PCI_COMMAND_IO))
+	io_sethandler(dev->midigame_base, 4, pipc_midigame_read, NULL, NULL, pipc_midigame_write, NULL, NULL, dev);
+}
+
+
+static void
+pipc_codec_handlers(pipc_t *dev, uint8_t modem)
+{
+    if (!dev->ac97)
+    	return;
+
+    if (modem)
+    	ac97_via_remap_modem_codec(dev->ac97, dev->ac97_regs[1][0x1d] << 8, dev->ac97_regs[1][0x04] & PCI_COMMAND_IO);
+    else
+    	ac97_via_remap_audio_codec(dev->ac97, dev->ac97_regs[0][0x1d] << 8, dev->ac97_regs[0][0x04] & PCI_COMMAND_IO);
+}
+
+
 static uint8_t
 pipc_read(int func, int addr, void *priv)
 {
@@ -487,8 +581,12 @@ pipc_read(int func, int addr, void *priv)
 			ret |= 0x10;
 	}
     }
-    else if ((func <= (pm_func + 2)) && !(dev->pci_isa_regs[0x85] & ((func == (pm_func + 1)) ? 0x04 : 0x08))) /* AC97 / MC97 */
-	ret = dev->ac97_regs[func - pm_func - 1][addr];
+    else if ((func <= (pm_func + 2)) && !(dev->pci_isa_regs[0x85] & ((func == (pm_func + 1)) ? 0x04 : 0x08))) { /* AC97 / MC97 */
+	if (addr == 0x40)
+		ret = ac97_via_read_status(dev->ac97, func - pm_func - 1);
+	else
+		ret = dev->ac97_regs[func - pm_func - 1][addr];
+    }
 
     pipc_log("PIPC: read(%d, %02X) = %02X\n", func, addr, ret);
 
@@ -528,7 +626,7 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
     pipc_log("PIPC: write(%d, %02X, %02X)\n", func, addr, val);
 
     if (func == 0) { /* PCI-ISA bridge */
-	/* Read-only addresses */
+	/* Read-only addresses. */
 	if ((addr < 4) || (addr == 5) || ((addr >= 8) && (addr < 0x40)) || (addr == 0x49) || (addr == 0x4b) ||
 	    (addr == 0x53) || ((addr >= 0x5d) && (addr < 0x5f)) || (addr >= 0x90))
 		return;
@@ -693,7 +791,7 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			break;
 	}
     } else if (func == 1) { /* IDE */
-	/* Read-only addresses and disable bit */
+	/* Read-only addresses. */
 	if ((addr < 4) || (addr == 5) || (addr == 8) || ((addr >= 0xa) && (addr < 0x0d)) ||
 	    ((addr >= 0x0e) && (addr < 0x10)) || ((addr >= 0x12) && (addr < 0x13)) ||
 	    ((addr >= 0x16) && (addr < 0x17)) || ((addr >= 0x1a) && (addr < 0x1b)) ||
@@ -702,12 +800,16 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 	    ((addr >= 0x62) && (addr < 0x68)) || ((addr >= 0x6a) && (addr < 0x70)) ||
 	    (addr == 0x72) || (addr == 0x73) || (addr == 0x76) || (addr == 0x77) ||
 	    (addr == 0x7a) || (addr == 0x7b) || (addr == 0x7e) || (addr == 0x7f) ||
-	    ((addr >= 0x84) && (addr < 0x88)) || (addr >= 0x8c) || (dev->pci_isa_regs[0x48] & 0x02))
+	    ((addr >= 0x84) && (addr < 0x88)) || (addr >= 0x8c))
 		return;
 
 	if ((dev->local <= VIA_PIPC_586B) && ((addr == 0x54) || (addr >= 0x70)))
 		return;
 
+	/* Check disable bit. */
+	if (dev->pci_isa_regs[0x48] & 0x02)
+		return;
+
 	switch (addr) {
 		case 0x04:
 			dev->ide_regs[0x04] = val & 0x85;
@@ -851,18 +953,18 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			break;
 	}
     } else if (func < pm_func) { /* USB */
-	/* Read-only addresses */
+	/* Read-only addresses. */
 	if ((addr < 4) || (addr == 5) || (addr == 6) || ((addr >= 8) && (addr < 0xd)) ||
 	    ((addr >= 0xe) && (addr < 0x20)) || ((addr >= 0x22) && (addr < 0x3c)) ||
 	    ((addr >= 0x3e) && (addr < 0x40)) || ((addr >= 0x42) && (addr < 0x44)) ||
 	    ((addr >= 0x46) && (addr < 0x84)) || ((addr >= 0x85) && (addr < 0xc0)) || (addr >= 0xc2))
 		return;
 
-	/* Check disable bits for both controllers */
-	if ((func == 2) ? (dev->pci_isa_regs[0x48] & 0x04) : (dev->pci_isa_regs[0x85] & 0x10))
+	if ((dev->local <= VIA_PIPC_596B) && (addr == 0x84))
 		return;
 
-	if ((dev->local <= VIA_PIPC_596B) && (addr == 0x84))
+	/* Check disable bits for both controllers. */
+	if ((func == 2) ? (dev->pci_isa_regs[0x48] & 0x04) : (dev->pci_isa_regs[0x85] & 0x10))
 		return;
 
 	switch (addr) {
@@ -965,22 +1067,78 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			break;
 	}
     } else if (func <= pm_func + 2) { /* AC97 / MC97 */
-	/* Read-only addresses */
-	if ((addr < 0x4) || ((addr >= 0x6) && (addr < 0xd)) || ((addr >= 0xe) && (addr < 0x10)) || ((addr >= 0x1c) && (addr < 0x2c)) ||
+	/* Read-only addresses. */
+	if ((addr < 0x4) || ((addr >= 0x6) && (addr < 0x9)) || ((addr >= 0xc) && (addr < 0x11)) || (addr == 0x16) ||
+	    (addr == 0x17) || (addr == 0x1a) || (addr == 0x1b) || ((addr >= 0x1e) && (addr < 0x2c)) ||
 	    ((addr >= 0x30) && (addr < 0x34)) || ((addr >= 0x35) && (addr < 0x3c)) || ((addr >= 0x3d) && (addr < 0x41)) ||
 	    ((addr >= 0x45) && (addr < 0x4a)) || (addr >= 0x4c))
 		return;
 
-	/* Also check disable bits for both controllers */
-	if ((func == (pm_func + 1)) && ((addr == 0x44) || (dev->pci_isa_regs[0x85] & 0x04)))
+	/* Small shortcut. */
+	func = func - pm_func - 1;
+
+	/* Check disable bits and specific read-only addresses for both controllers. */
+	if ((func == 0) && (((addr >= 0x09) && (addr < 0xc)) || (addr == 0x44) || (dev->pci_isa_regs[0x85] & 0x04)))
 		return;
 
-	if ((func == (pm_func + 2)) && ((addr == 0x4a) || (addr == 0x4b) || (dev->pci_isa_regs[0x85] & 0x08)))
+	if ((func == 1) && ((addr == 0x14) || (addr == 0x15) || (addr == 0x18) || (addr == 0x19) || (addr == 0x42) ||
+	    (addr == 0x43) || (addr == 0x48) || (addr == 0x4a) || (addr == 0x4b) || (dev->pci_isa_regs[0x85] & 0x08)))
 		return;
 
 	switch (addr) {
+		case 0x04:
+			dev->ac97_regs[func][addr] = val;
+			pipc_midigame_handlers(dev, func);
+			pipc_sgd_handlers(dev, func);
+			pipc_codec_handlers(dev, func);
+			break;
+
+		case 0x09: case 0x0a: case 0x0b:
+			if (dev->ac97_regs[func][0x44] & 0x20)
+				dev->ac97_regs[func][addr] = val;
+			break;
+
+		case 0x11:
+			dev->ac97_regs[func][addr] = val;
+			pipc_sgd_handlers(dev, func);
+			break;
+
+		case 0x18: case 0x19:
+			if (addr == 0x18)
+				val = (val & 0xfc) | 1;
+			dev->ac97_regs[func][addr] = val;
+			pipc_midigame_handlers(dev, func);
+			break;
+
+		case 0x1c:
+			dev->ac97_regs[func][addr] = val;
+			pipc_codec_handlers(dev, func);
+			break;
+
+		case 0x2c: case 0x2d: case 0x2e: case 0x2f:
+			if ((func == 0) && (dev->ac97_regs[func][0x42] & 0x20))
+				dev->ac97_regs[func][addr] = val;
+			break;
+
+		case 0x42: case 0x4a: case 0x4b:
+			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val;
+			gameport_remap(dev->gameport, (dev->ac97_regs[0][0x42] & 0x08) ? ((dev->ac97_regs[0][0x4b] << 8) | dev->ac97_regs[0][0x4a]) : 0);
+			break;
+
+		case 0x43:
+			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val;
+			break;
+
+		case 0x44:
+			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val & 0xf0;
+			break;
+
+		case 0x45:
+			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val & 0x0f;
+			break;
+
 		default:
-			dev->ac97_regs[func - pm_func - 1][addr] = val;
+			dev->ac97_regs[func][addr] = val;
 			break;
 	}
     }
@@ -1052,9 +1210,15 @@ pipc_init(const device_t *info)
 	dev->acpi = device_add(&acpi_via_device);
 
     dev->usb[0] = device_add_inst(&usb_device, 1);
-    if (dev->local >= VIA_PIPC_686A)
+    if (dev->local >= VIA_PIPC_686A) {
 	dev->usb[1] = device_add_inst(&usb_device, 2);
 
+	dev->ac97 = device_add(&ac97_via_device);
+	ac97_via_set_slot(dev->ac97, dev->slot, PCI_INTC);
+
+	dev->gameport = gameport_add(&gameport_sio_device);
+    }
+
     pipc_reset_hard(dev);
 
     device_add(&port_92_pci_device);
diff --git a/src/device/hasp.c b/src/device/hasp.c
index 2c6aca190..60dae74c6 100644
--- a/src/device/hasp.c
+++ b/src/device/hasp.c
@@ -50,6 +50,7 @@ enum {
     HASP_TYPE_SAVQUEST = 0
 };
 
+
 typedef struct {
     const uint8_t *password, *prodinfo;
     const uint8_t password_size, prodinfo_size;
@@ -266,7 +267,7 @@ hasp_read_status(void *priv)
 static void *
 hasp_init(void *lpt, int type)
 {
-    hasp_t *dev = (hasp_t *) malloc(sizeof(hasp_t));
+    hasp_t *dev = malloc(sizeof(hasp_t));
     memset(dev, 0, sizeof(hasp_t));
 
     hasp_log("HASP: init(%d)\n", type);
diff --git a/src/game/gameport.c b/src/game/gameport.c
index b0caff22a..80c686ec2 100644
--- a/src/game/gameport.c
+++ b/src/game/gameport.c
@@ -324,7 +324,7 @@ gameport_remap(void *priv, uint16_t address)
 
     if (dev->addr) {
 	/* Add this port to the active ports list. */
-	if ( !active_gameports || ((dev->addr & 0xfff8) == 0x200)) {
+	if (!active_gameports || ((dev->addr & 0xfff8) == 0x200)) {
 		/* No ports have been added yet, or port within 200-207h: add to top. */
 		dev->next = active_gameports;
 		active_gameports = dev;
diff --git a/src/include/86box/device.h b/src/include/86box/device.h
index 4226eee81..ec567bf57 100644
--- a/src/include/86box/device.h
+++ b/src/include/86box/device.h
@@ -65,7 +65,8 @@ enum {
     DEVICE_EISA = 0x100,	/* requires the EISA bus */
     DEVICE_VLB = 0x200,		/* requires the PCI bus */
     DEVICE_PCI = 0x400,		/* requires the VLB bus */
-    DEVICE_AGP = 0x800		/* requires the AGP bus */
+    DEVICE_AGP = 0x800,		/* requires the AGP bus */
+    DEVICE_AC97 = 0x1000	/* requires the AC'97 bus */
 };
 
 
diff --git a/src/include/86box/snd_ac97.h b/src/include/86box/snd_ac97.h
new file mode 100644
index 000000000..8d66cdea4
--- /dev/null
+++ b/src/include/86box/snd_ac97.h
@@ -0,0 +1,49 @@
+/*
+ * 86Box	A hypervisor and IBM PC system emulator that specializes in
+ *		running old operating systems and software designed for IBM
+ *		PC systems and compatibles from 1981 through fairly recent
+ *		system designs based on the PCI bus.
+ *
+ *		This file is part of the 86Box distribution.
+ *
+ *		Definitions for AC'97 audio emulation.
+ *
+ *
+ *
+ * Authors:	RichardG, <richardg867@gmail.com>
+ *
+ *		Copyright 2021 RichardG.
+ */
+#ifndef EMU_SND_AC97_H
+# define EMU_SND_AC97_H
+
+
+typedef struct {
+    uint32_t	id;
+    uint8_t	regs[128];
+} ac97_codec_t;
+
+
+extern uint8_t	ac97_codec_read(ac97_codec_t *dev, uint8_t reg);
+extern void	ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val);
+extern void	ac97_codec_reset(void *priv);
+
+extern void	ac97_via_set_slot(void *priv, int slot, int irq_pin);
+extern uint8_t	ac97_via_read_status(void *priv, uint8_t modem);
+extern void	ac97_via_remap_audio_sgd(void *priv, uint16_t new_io_base, uint8_t enable);
+extern void	ac97_via_remap_modem_sgd(void *priv, uint16_t new_io_base, uint8_t enable);
+extern void	ac97_via_remap_audio_codec(void *priv, uint16_t new_io_base, uint8_t enable);
+extern void	ac97_via_remap_modem_codec(void *priv, uint16_t new_io_base, uint8_t enable);
+
+
+#ifdef EMU_DEVICE_H
+extern ac97_codec_t	**ac97_codec, **ac97_modem_codec;
+extern int		ac97_codec_count, ac97_modem_codec_count;
+
+extern const device_t	alc100_device;
+
+extern const device_t	ac97_via_device;
+#endif
+
+
+#endif
diff --git a/src/machine/m_at_socket370.c b/src/machine/m_at_socket370.c
index b7a83befb..cc2e1718a 100644
--- a/src/machine/m_at_socket370.c
+++ b/src/machine/m_at_socket370.c
@@ -37,6 +37,7 @@
 #include "cpu.h"
 #include <86box/machine.h>
 #include <86box/clock.h>
+#include <86box/snd_ac97.h>
 
 
 int
@@ -432,7 +433,7 @@ machine_at_6via90ap_init(const machine_t *model)
 
     pci_init(PCI_CONFIG_TYPE_1);
     pci_register_slot(0x00, PCI_CARD_NORTHBRIDGE, 0, 0, 0, 0);
-    pci_register_slot(0x07, PCI_CARD_SOUTHBRIDGE, 1, 2, 0, 0);
+    pci_register_slot(0x07, PCI_CARD_SOUTHBRIDGE, 1, 2, 3, 4);
     pci_register_slot(0x09, PCI_CARD_NORMAL,      1, 2, 3, 4);
     pci_register_slot(0x0A, PCI_CARD_NORMAL,      2, 3, 4, 1);
     pci_register_slot(0x0B, PCI_CARD_NORMAL,      3, 4, 1, 2);
@@ -451,6 +452,10 @@ machine_at_6via90ap_init(const machine_t *model)
     hwm_values.temperatures[1] += 2; /* System offset */
     hwm_values.temperatures[2] = 0; /* unused */
 
+    /* I recall identifying this board's codec as the ALC100 while studying AC97, but I couldn't find
+       that information again. Other Acorp boards have the ALC100, though, so it's a safe bet. -RG */
+    device_add(&alc100_device);
+
     return ret;
 }
 
diff --git a/src/machine/machine_table.c b/src/machine/machine_table.c
index a952c2b4e..c60982831 100644
--- a/src/machine/machine_table.c
+++ b/src/machine/machine_table.c
@@ -461,7 +461,7 @@ const machine_t machines[] = {
     { "[VIA Apollo Pro133] ECS P6BAP",		"p6bap",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, 1.5, 8.0,						MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,	  			 8192,1572864, 8192, 255,		machine_at_p6bap_init, NULL			},
     { "[VIA Apollo Pro133A] AEWIN WCF-681",	"wcf681",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 133333333, 1300, 3500, 1.5, 8.0, /* limits assumed */				MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,	  			 8192,1048576, 8192, 255,	       machine_at_wcf681_init, NULL			},
     { "[VIA Apollo Pro133A] ASUS CUV4X-LS",	"cuv4xls",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, 1.5, 8.0,						(MACHINE_AGP & ~MACHINE_AT) | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,		16384,1572864, 8192, 255,	      machine_at_cuv4xls_init, NULL			},
-    { "[VIA Apollo Pro133A] Acorp 6VIA90AP",	"6via90ap",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, MACHINE_MULTIPLIER_FIXED,				MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,	  			 8192,1572864, 8192, 255,	     machine_at_6via90ap_init, NULL			},
+    { "[VIA Apollo Pro133A] Acorp 6VIA90AP",	"6via90ap",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, MACHINE_MULTIPLIER_FIXED,				MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL | MACHINE_GAMEPORT,		 8192,1572864, 8192, 255,	     machine_at_6via90ap_init, NULL			},
     { "[VIA Apollo ProMedia] Jetway 603TCF",	"603tcf",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, 1.5, 8.0,						MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,	  			 8192,1048576, 8192, 255,	       machine_at_603tcf_init, NULL			},
 
     /* Miscellaneous/Fake/Hypervisor machines */
diff --git a/src/pci.c b/src/pci.c
index 5f1c48f50..a4272e6bd 100644
--- a/src/pci.c
+++ b/src/pci.c
@@ -73,7 +73,7 @@ static int		trc_reg = 0;
 
 static void		pci_reset_regs(void);
 
-
+#define ENABLE_PCI_LOG 1
 #ifdef ENABLE_PCI_LOG
 int pci_do_log = ENABLE_PCI_LOG;
 
diff --git a/src/sound/CMakeLists.txt b/src/sound/CMakeLists.txt
index d991e5cc2..f5a6435c4 100644
--- a/src/sound/CMakeLists.txt
+++ b/src/sound/CMakeLists.txt
@@ -14,7 +14,7 @@
 #
 
 add_library(snd OBJECT sound.c openal.c snd_opl.c snd_opl_nuked.c snd_resid.cc
-	midi.c midi_system.c snd_speaker.c snd_pssj.c snd_lpt_dac.c
+	midi.c midi_system.c snd_speaker.c snd_pssj.c snd_lpt_dac.c snd_ac97_codec.c snd_ac97_via.c
 	snd_lpt_dss.c snd_adlib.c snd_adlibgold.c snd_ad1848.c snd_audiopci.c
 	snd_azt2316a.c snd_cms.c snd_cs423x.c snd_gus.c snd_sb.c snd_sb_dsp.c
 	snd_emu8k.c snd_mpu401.c snd_sn76489.c snd_ssi2001.c snd_wss.c snd_ym7128.c)
diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
new file mode 100644
index 000000000..e96795011
--- /dev/null
+++ b/src/sound/snd_ac97_codec.c
@@ -0,0 +1,227 @@
+/*
+ * 86Box	A hypervisor and IBM PC system emulator that specializes in
+ *		running old operating systems and software designed for IBM
+ *		PC systems and compatibles from 1981 through fairly recent
+ *		system designs based on the PCI bus.
+ *
+ *		This file is part of the 86Box distribution.
+ *
+ *		AC'97 audio codec emulation.
+ *
+ *
+ *
+ * Authors:	RichardG, <richardg867@gmail.com>
+ *
+ *		Copyright 2021 RichardG.
+ */
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+#define HAVE_STDARG_H
+#include <86box/86box.h>
+#include <86box/device.h>
+#include <86box/io.h>
+#include <86box/snd_ac97.h>
+
+#define AC97_CODEC_ID(f, s, t, dev)	((((f) & 0xff) << 24) | (((s) & 0xff) << 16) | (((t) & 0xff) << 8) | ((dev) & 0xff))
+
+
+enum {
+    AC97_CODEC_ALC100 = AC97_CODEC_ID('A', 'L', 'C', 0x20)
+};
+
+#define ENABLE_AC97_CODEC_LOG 1
+#ifdef ENABLE_AC97_CODEC_LOG
+int ac97_codec_do_log = ENABLE_AC97_CODEC_LOG;
+
+static void
+ac97_codec_log(const char *fmt, ...)
+{
+    va_list ap;
+
+    if (ac97_codec_do_log) {
+	va_start(ap, fmt);
+	pclog_ex(fmt, ap);
+	va_end(ap);
+    }
+}
+#else
+#define ac97_codec_log(fmt, ...)
+#endif
+
+ac97_codec_t	**ac97_codec = NULL, **ac97_modem_codec = NULL;
+int		ac97_codec_count = 0, ac97_modem_codec_count = 0;
+
+
+uint8_t
+ac97_codec_read(ac97_codec_t *dev, uint8_t reg)
+{
+    uint8_t ret = dev->regs[reg & 0x7f];
+
+    ac97_codec_log("AC97 Codec: read(%02X) = %02X\n", reg, ret);
+
+    return ret;
+}
+
+
+void
+ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
+{
+    ac97_codec_log("AC97 Codec: write(%02X, %02X)\n", reg, val);
+
+    reg &= 0x7f;
+
+    switch (reg) {
+	case 0x00: case 0x01: /* Reset / ID code */
+		ac97_codec_reset(dev);
+		/* fall-through */
+
+	case 0x08: case 0x09: /* Master Tone Control (optional) */
+	case 0x0d: /* Phone Volume MSB */
+	case 0x0f: /* Mic Volume MSB */
+	case 0x1e: case 0x1f: /* Record Gain Mic (optional) */
+	case 0x22: case 0x23: /* 3D Control (optional) */
+	case 0x24: case 0x25: /* Audio Interrupt and Paging Mechanism (optional) */
+	case 0x26: /* Powerdown Ctrl/Stat LSB */
+	case 0x28: case 0x29: /* Extended Audio ID */
+	//case 0x2a ... 0x59: /* Linux tests for audio capability by writing to 38-39 */
+	case 0x5a ... 0x5f: /* Vendor Reserved */
+	//case 0x60 ... 0x6f:
+	case 0x70 ... 0x7b: /* Vendor Reserved */
+		/* Read-only registers. */
+		return;
+
+	case 0x03: /* Master Volume MSB */
+	case 0x05: /* Aux Out Volume MSB */
+		val &= 0xbf;
+		break;
+
+	case 0x07: /* Mono Volume MSB */
+	case 0x20: /* General Purpose LSB */
+		val &= 0x80;
+		break;
+
+	case 0x02: /* Master Volume LSB */
+	case 0x04: /* Aux Out Volume LSB */
+	case 0x06: /* Mono Volume LSB */
+	case 0x0b: /* PC Beep Volume MSB */
+		val &= 0x3f;
+		break;
+
+	case 0x0a: /* PC Beep Volume LSB */
+		val &= 0xfe;
+		break;
+
+	case 0x0c: /* Phone Volume LSB */
+	case 0x10: /* Line In Volume LSB */
+	case 0x12: /* CD Volume LSB */
+	case 0x14: /* Video Volume LSB */
+	case 0x16: /* Aux In Volume LSB */
+	case 0x18: /* PCM Out Volume LSB */
+		val &= 0x1f;
+		break;
+
+	case 0x0e: /* Mic Volume LSB */
+		val &= 0x5f;
+		break;
+
+	case 0x11: /* Line In Volume MSB */
+	case 0x13: /* CD Volume MSB */
+	case 0x15: /* Video Volume MSB */
+	case 0x17: /* Aux In Volume MSB */
+	case 0x19: /* PCM Out Volume MSB */
+		val &= 0x9f;
+		break;
+
+	case 0x1a: case 0x1b: /* Record Select */
+		val &= 0x07;
+		break;
+
+	case 0x1c: /* Record Gain LSB */
+		val &= 0x0f;
+		break;
+
+	case 0x1d: /* Record Gain MSB */
+		val &= 0x8f;
+		break;
+
+	case 0x21: /* General Purpose MSB */
+		val &= 0x83;
+		break;
+    }
+
+    dev->regs[reg] = val;
+}
+
+
+void
+ac97_codec_reset(void *priv)
+{
+    ac97_codec_t *dev = (ac97_codec_t *) priv;
+
+    ac97_codec_log("AC97 Codec: reset()\n");
+
+    memset(dev->regs, 0, sizeof(dev->regs));
+
+    /* Mute outputs by default. */
+    dev->regs[0x02] = dev->regs[0x04] = dev->regs[0x06] = 0x80;
+
+    /* Flag codec as ready. */
+    dev->regs[0x26] = 0x0f;
+
+    /* Set Vendor ID. */
+    dev->regs[0x7c] = dev->id >> 16;
+    dev->regs[0x7d] = dev->id >> 24;
+    dev->regs[0x7e] = dev->id >> 8;
+    dev->regs[0x7f] = dev->id;
+}
+
+
+static void *
+ac97_codec_init(const device_t *info)
+{
+    ac97_codec_t *dev = malloc(sizeof(ac97_codec_t));
+    memset(dev, 0, sizeof(ac97_codec_t));
+
+    dev->id = info->local;
+    ac97_codec_log("AC97 Codec: init(%c%c%c%02X)\n", (dev->id >> 24) & 0xff, (dev->id >> 16) & 0xff, (dev->id >> 8) & 0xff, dev->id & 0xff);
+
+    /* Associate this codec to the current controller. */
+    if (!ac97_codec || (ac97_codec_count <= 0)) {
+    	fatal("AC97 Codec: No controller to associate codec");
+    	return NULL;
+    }
+    *ac97_codec = dev;
+    if (--ac97_codec_count == 0)
+	ac97_codec = NULL;
+    else
+	ac97_codec += sizeof(ac97_codec_t *);
+
+    return dev;
+}
+
+
+static void
+ac97_codec_close(void *priv)
+{
+    ac97_codec_t *dev = (ac97_codec_t *) priv;
+
+    ac97_codec_log("AC97 Codec: close()\n");
+
+    free(dev);
+}
+
+
+const device_t alc100_device =
+{
+    "Avance Logic ALC100",
+    DEVICE_AC97,
+    AC97_CODEC_ALC100,
+    ac97_codec_init, ac97_codec_close, ac97_codec_reset,
+    { NULL },
+    NULL,
+    NULL,
+    NULL
+};
diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
new file mode 100644
index 000000000..3e83e20c2
--- /dev/null
+++ b/src/sound/snd_ac97_via.c
@@ -0,0 +1,638 @@
+/*
+ * 86Box	A hypervisor and IBM PC system emulator that specializes in
+ *		running old operating systems and software designed for IBM
+ *		PC systems and compatibles from 1981 through fairly recent
+ *		system designs based on the PCI bus.
+ *
+ *		This file is part of the 86Box distribution.
+ *
+ *		VIA AC'97 audio controller emulation.
+ *
+ *
+ *
+ * Authors:	RichardG, <richardg867@gmail.com>
+ *
+ *		Copyright 2021 RichardG.
+ */
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+#define HAVE_STDARG_H
+#include <86box/86box.h>
+#include <86box/device.h>
+#include <86box/io.h>
+#include <86box/mem.h>
+#include <86box/pic.h>
+#include <86box/timer.h>
+#include <86box/pci.h>
+#include <86box/sound.h>
+#include <86box/snd_ac97.h>
+
+#define SGD_UNPAUSED	(dev->sgd_regs[0x00] & 0xc4) == 0x80
+
+
+typedef struct {
+    uint16_t	audio_sgd_base, audio_codec_base, modem_sgd_base, modem_codec_base;
+    uint8_t	sgd_regs[256], irq_stuck;
+    int		slot, irq_pin, losticount;
+    uint64_t	sgd_entry;
+    uint32_t	sgd_entry_ptr, sgd_sample_ptr;
+    int32_t	sgd_sample_count;
+
+    ac97_codec_t *codec[4];
+
+    pc_timer_t	timer_count;
+    uint64_t	timer_latch;
+    int16_t	out_l, out_r;
+    double	cd_vol_l, cd_vol_r;
+    int16_t	buffer[SOUNDBUFLEN * 2];
+    int		pos;
+} ac97_via_t;
+
+#define ENABLE_AC97_VIA_LOG 1
+#ifdef ENABLE_AC97_VIA_LOG
+int ac97_via_do_log = ENABLE_AC97_VIA_LOG;
+
+static void
+ac97_via_log(const char *fmt, ...)
+{
+    va_list ap;
+
+    if (ac97_via_do_log) {
+	va_start(ap, fmt);
+	pclog_ex(fmt, ap);
+	va_end(ap);
+    }
+}
+#else
+#define ac97_via_log(fmt, ...)
+#endif
+
+
+static void	ac97_via_poll(void *priv);
+
+
+void
+ac97_via_set_slot(void *priv, int slot, int irq_pin)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+
+    ac97_via_log("AC97 VIA: set_slot(%d, %d)\n", slot, irq_pin);
+
+    dev->slot = slot;
+    dev->irq_pin = irq_pin;
+}
+
+
+uint8_t
+ac97_via_read_status(void *priv, uint8_t modem)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    uint8_t ret = 0x00;
+
+    /* Flag codecs as ready if present. */
+    for (uint8_t i = 0; i <= 1; i++) {
+	if (dev->codec[(modem << 1) | i])
+		ret |= 0x01 << (i << 1);
+    }
+
+    ac97_via_log("AC97 VIA %d: read_status() = %02X\n", modem, ret);
+
+    return ret;
+}
+
+
+static void
+ac97_via_sgd_startstop(ac97_via_t *dev)
+{
+    /* Start polling timer if SGD is unpaused. */
+#if 0
+    if (SGD_UNPAUSED) {
+	ac97_via_log("AC97 VIA: Starting SGD at %08X\n", dev->sgd_entry_ptr);
+	timer_set_delay_u64(&dev->timer_count, dev->timer_latch);
+    } else {
+	ac97_via_log("AC97 VIA: Stopping SGD\n");
+	timer_disable(&dev->timer_count);
+	dev->out_l = dev->out_r = 0;
+    }
+#endif
+}
+
+
+static void
+ac97_via_sgd_block_start(ac97_via_t *dev)
+{
+    /* Start at first entry. */
+    /*if (!dev->sgd_entry_ptr)
+	dev->sgd_entry_ptr = (dev->sgd_regs[0x07] << 24) | (dev->sgd_regs[0x06] << 16) | (dev->sgd_regs[0x05] << 8) | (dev->sgd_regs[0x04] & 0xfe);*/
+
+    /* Read entry. */
+    dev->sgd_entry = ((uint64_t) mem_readl_phys(dev->sgd_entry_ptr + 4) << 32ULL) | (uint64_t) mem_readl_phys(dev->sgd_entry_ptr);
+    if (dev->sgd_entry == 0xffffffffffffffffULL)
+	fatal("AC97 VIA: Invalid SGD entry at %08X\n", dev->sgd_entry_ptr);
+
+    /* Set sample pointer and count. */
+    dev->sgd_sample_ptr = dev->sgd_entry & 0xffffffff;
+    dev->sgd_sample_count = (dev->sgd_entry >> 32) & 0xffffff;
+
+    ac97_via_log("AC97 VIA: Starting SGD block at %08X entry %08X%08X (start %08X len %06X) losticount %d\n",
+		 dev->sgd_entry_ptr, mem_readl_phys(dev->sgd_entry_ptr + 4), mem_readl_phys(dev->sgd_entry_ptr), dev->sgd_sample_ptr, dev->sgd_sample_count, dev->losticount);
+}
+
+
+uint8_t
+ac97_via_sgd_read(uint16_t addr, void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    uint8_t modem = (addr & 0xff00) == dev->modem_sgd_base;
+    addr &= 0xff;
+    uint8_t ret = 0x00;
+
+    switch (addr) {
+	case 0x04:
+		ret = dev->sgd_entry_ptr;
+		break;
+
+	case 0x05:
+		ret = dev->sgd_entry_ptr >> 8;
+		break;
+
+	case 0x06:
+		ret = dev->sgd_entry_ptr >> 16;
+		break;
+
+	case 0x07:
+		ret = dev->sgd_entry_ptr >> 24;
+		/*pclog("sgd state %02X unpaused %d rct %02X\n", dev->sgd_regs[0x00], SGD_UNPAUSED, dev->sgd_regs[0x02]);
+		pci_clear_irq(dev->slot, dev->irq_pin);*/
+		break;
+
+	case 0x0c:
+		ret = dev->sgd_sample_count;
+		break;
+
+	case 0x0d:
+		ret = dev->sgd_sample_count >> 8;
+		break;
+
+	case 0x0e:
+		ret = dev->sgd_sample_count >> 16;
+		break;
+
+	case 0x84:
+		ret |= (dev->sgd_regs[0x00] & 0x01);
+		ret |= (dev->sgd_regs[0x10] & 0x01) << 1;
+		ret |= (dev->sgd_regs[0x20] & 0x01) << 2;
+
+		ret |= (dev->sgd_regs[0x00] & 0x02) << 3;
+		ret |= (dev->sgd_regs[0x10] & 0x02) << 4;
+		ret |= (dev->sgd_regs[0x20] & 0x02) << 5;
+		break;
+
+	case 0x85:
+		ret |= (dev->sgd_regs[0x00] & 0x04) >> 2;
+		ret |= (dev->sgd_regs[0x10] & 0x04) >> 1;
+		ret |= (dev->sgd_regs[0x20] & 0x04);
+
+		ret |= (dev->sgd_regs[0x00] & 0x80) >> 3;
+		ret |= (dev->sgd_regs[0x10] & 0x80) >> 2;
+		ret |= (dev->sgd_regs[0x20] & 0x80) >> 1;
+		break;
+
+	case 0x86:
+		ret |= (dev->sgd_regs[0x40] & 0x01);
+		ret |= (dev->sgd_regs[0x50] & 0x01) << 1;
+
+		ret |= (dev->sgd_regs[0x40] & 0x02) << 3;
+		ret |= (dev->sgd_regs[0x50] & 0x02) << 4;
+		break;
+
+	case 0x87:
+		ret |= (dev->sgd_regs[0x40] & 0x04) >> 2;
+		ret |= (dev->sgd_regs[0x50] & 0x04) >> 1;
+
+		ret |= (dev->sgd_regs[0x40] & 0x80) >> 3;
+		ret |= (dev->sgd_regs[0x50] & 0x80) >> 2;
+		break;
+
+	default:
+		ret = dev->sgd_regs[addr];
+		break;
+    }
+
+    ac97_via_log("AC97 VIA %d: sgd_read(%02X) = %02X\n", modem, addr, ret);
+
+    return ret;
+}
+
+
+void
+ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    uint8_t modem = (addr & 0xff00) == dev->modem_sgd_base, i;
+    ac97_codec_t *codec;
+    addr &= 0xff;
+
+    ac97_via_log("AC97 VIA %d: sgd_write(%02X, %02X)\n", modem, addr, val);
+
+    /* Check function-specific read only registers. */
+    if ((addr >= (modem ? 0x00 : 0x40)) && (addr < (modem ? 0x40 : 0x60)))
+	return;
+    if (addr >= (modem ? 0x90 : 0x88))
+	return;
+
+    /* Check read-only registers for each SGD channel. */
+    if (!(addr & 0x80)) {
+	switch (addr & 0xf) {
+		case 0x0:
+			/* Clear RWC status bits. */
+			for (i = 0x01; i <= 0x04; i <<= 1) {
+				if (val & i)
+					dev->sgd_regs[addr] &= ~i;
+			}
+
+			if (addr == 0x00) {
+				if (!(dev->sgd_regs[0x00] & (dev->sgd_regs[0x02] & 0x03))) {
+					ac97_via_log("AC97 VIA: Clearing IRQ (iflags %02X)\n", dev->sgd_regs[0x00] & (dev->sgd_regs[0x02] & 0x03));
+					pci_clear_irq(dev->slot, dev->irq_pin);
+					dev->irq_stuck = 0;
+				}
+
+				/* Resume SGD if requested. */
+				if (val & 0x04)
+					ac97_via_sgd_startstop(dev);
+			}
+
+			/* fall-through */
+
+		case 0x3: case 0x8 ... 0xf:
+			return;
+	}
+    }
+
+    switch (addr) {
+	case 0x30 ... 0x3f:
+	case 0x60 ... 0x7f:
+		/* Read-only registers. */
+		return;
+
+	case 0x01:
+		/* Start SGD if requested. */
+		if (val & 0x80) {
+			if (dev->sgd_regs[0x00] & 0x80) {
+				/* Queue SGD trigger. */
+				dev->sgd_regs[0x00] |= 0x08;
+			} else {
+				/* Start SGD immediately. */
+				dev->sgd_regs[0x00] |= 0x80;
+				dev->sgd_regs[0x00] &= ~0x44;
+
+				dev->sgd_entry = 0;
+				dev->sgd_entry_ptr = (dev->sgd_regs[0x07] << 24) | (dev->sgd_regs[0x06] << 16) | (dev->sgd_regs[0x05] << 8) | (dev->sgd_regs[0x04] & 0xfe);
+			}
+		}
+		/* Stop SGD if requested. */
+		if (val & 0x40) {
+			dev->sgd_regs[0x00] &= ~0x88;
+		}
+
+		val &= 0x04;
+
+		/* (Un)pause SGD if requested. */
+		if (val & 0x04)
+			dev->sgd_regs[0x00] |= 0x40;
+		else
+			dev->sgd_regs[0x00] &= ~0x40;
+
+		ac97_via_sgd_startstop(dev);
+		break;
+
+	case 0x82:
+		/* Determine the selected codec. */
+		i = !!(dev->sgd_regs[0x83] & 0x40);
+		codec = dev->codec[(modem << 1) | i];
+
+		/* Read from or write to codec. */
+		if (codec) {
+			if (val & 0x80) {
+				val <<= 1;
+				dev->sgd_regs[0x80] = ac97_codec_read(codec, val);
+				dev->sgd_regs[0x81] = ac97_codec_read(codec, val | 1);
+			} else {
+				val <<= 1;
+				ac97_codec_write(codec, val, dev->sgd_regs[0x80]);
+				ac97_codec_write(codec, val | 1, dev->sgd_regs[0x81]);
+			}
+		} else if (val & 0x80) {
+			/* Unknown behavior when reading from a non-existent codec. */
+			dev->sgd_regs[0x80] = dev->sgd_regs[0x81] = 0xff;
+		}
+
+		/* Flag data/status/index for this codec as valid. */
+		dev->sgd_regs[0x83] |= 0x02 << (i * 2);
+		break;
+
+	case 0x83:
+		val &= 0xca;
+
+		/* Clear RWC bits. */
+		for (i = 0x02; i <= 0x08; i <<= 2) {
+#if 0 /* race condition with Linux clearing bits and starting SGD on the same dword write */
+			if (val & i)
+				val &= ~i;
+			else
+				val |= dev->sgd_regs[addr] & i;
+#else
+			val |= i;
+#endif
+		}
+		break;
+    }
+
+    dev->sgd_regs[addr] = val;
+}
+
+
+void
+ac97_via_remap_audio_sgd(void *priv, uint16_t new_io_base, uint8_t enable)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+
+    if (dev->audio_sgd_base)
+	io_removehandler(dev->audio_sgd_base, 256, ac97_via_sgd_read, NULL, NULL, ac97_via_sgd_write, NULL, NULL, dev);
+
+    dev->audio_sgd_base = new_io_base;
+
+    if (dev->audio_sgd_base && enable)
+	io_sethandler(dev->audio_sgd_base, 256, ac97_via_sgd_read, NULL, NULL, ac97_via_sgd_write, NULL, NULL, dev);
+}
+
+
+void
+ac97_via_remap_modem_sgd(void *priv, uint16_t new_io_base, uint8_t enable)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+
+    if (dev->modem_sgd_base)
+	io_removehandler(dev->modem_sgd_base, 256, ac97_via_sgd_read, NULL, NULL, ac97_via_sgd_write, NULL, NULL, dev);
+
+    dev->modem_sgd_base = new_io_base;
+
+    if (dev->modem_sgd_base && enable)
+	io_sethandler(dev->modem_sgd_base, 256, ac97_via_sgd_read, NULL, NULL, ac97_via_sgd_write, NULL, NULL, dev);
+}
+
+
+uint8_t
+ac97_via_codec_read(uint16_t addr, void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    uint8_t modem = (addr & 0xff00) == dev->modem_codec_base;
+    addr &= 0xff;
+    uint8_t ret = 0xff;
+
+    /* Bit 7 selects secondary codec. */
+    ac97_codec_t *codec = dev->codec[(modem << 1) | (addr >> 7)];
+    if (codec)
+	ret = ac97_codec_read(codec, addr & 0x7f);
+
+    ac97_via_log("AC97 VIA %d: codec_read(%02X) = %02X\n", modem, addr, ret);
+
+    return ret;
+}
+
+
+void
+ac97_via_codec_write(uint16_t addr, uint8_t val, void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    uint8_t modem = (addr & 0xff00) == dev->modem_codec_base;
+    addr &= 0xff;
+
+    ac97_via_log("AC97 VIA %d: codec_write(%02X, %02X)\n", modem, addr, val);
+
+    /* Bit 7 selects secondary codec. */
+    ac97_codec_t *codec = dev->codec[(modem << 1) | (addr >> 7)];
+    if (codec)
+	ac97_codec_write(codec, addr, val);
+}
+
+
+void
+ac97_via_remap_audio_codec(void *priv, uint16_t new_io_base, uint8_t enable)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+
+    if (dev->audio_codec_base)
+	io_removehandler(dev->audio_codec_base, 256, ac97_via_codec_read, NULL, NULL, ac97_via_codec_write, NULL, NULL, dev);
+
+    dev->audio_codec_base = new_io_base;
+
+    if (dev->audio_codec_base && enable)
+	io_sethandler(dev->audio_codec_base, 256, ac97_via_codec_read, NULL, NULL, ac97_via_codec_write, NULL, NULL, dev);
+}
+
+
+void
+ac97_via_remap_modem_codec(void *priv, uint16_t new_io_base, uint8_t enable)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+
+    if (dev->modem_codec_base)
+	io_removehandler(dev->modem_codec_base, 256, ac97_via_codec_read, NULL, NULL, ac97_via_codec_write, NULL, NULL, dev);
+
+    dev->modem_codec_base = new_io_base;
+
+    if (dev->modem_codec_base && enable)
+	io_sethandler(dev->modem_codec_base, 256, ac97_via_codec_read, NULL, NULL, ac97_via_codec_write, NULL, NULL, dev);
+}
+
+
+static void
+ac97_via_update(ac97_via_t *dev)
+{
+    for (; dev->pos < sound_pos_global; dev->pos++) {
+	dev->buffer[dev->pos*2]     = dev->out_l;
+	dev->buffer[dev->pos*2 + 1] = dev->out_r;
+    }
+}
+
+
+static void
+ac97_via_poll(void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    uint8_t irq = 0;
+
+    timer_advance_u64(&dev->timer_count, dev->timer_latch);
+
+    ac97_via_update(dev);
+
+    /* Read only if SGD is active and not paused. */
+    if (SGD_UNPAUSED) {
+	if (!dev->sgd_entry) {
+		/* Move on to the next block. */
+		ac97_via_sgd_block_start(dev);
+	}
+
+	switch (dev->sgd_regs[0x02] & 0x30) {
+		case 0x00: /* Mono, 8-bit PCM */
+			dev->out_l = dev->out_r = (mem_readb_phys(dev->sgd_sample_ptr++) ^ 0x80) * 256;
+			dev->sgd_sample_count--;
+			break;
+
+		case 0x10: /* Stereo, 8-bit PCM */
+			dev->out_l = (mem_readb_phys(dev->sgd_sample_ptr++) ^ 0x80) * 256;
+			dev->out_r = (mem_readb_phys(dev->sgd_sample_ptr++) ^ 0x80) * 256;
+			dev->sgd_sample_count -= 2;
+			break;
+
+		case 0x20: /* Mono, 16-bit PCM */
+			dev->out_l = dev->out_r = mem_readw_phys(dev->sgd_sample_ptr);
+			dev->sgd_sample_ptr += 2;
+			dev->sgd_sample_count -= 2;
+			break;
+
+		case 0x30: /* Stereo, 16-bit PCM */
+			dev->out_l = mem_readw_phys(dev->sgd_sample_ptr);
+			dev->sgd_sample_ptr += 2;
+			dev->out_r = mem_readw_phys(dev->sgd_sample_ptr);
+			dev->sgd_sample_ptr += 2;
+			dev->sgd_sample_count -= 4;
+			break;
+	}
+
+	/* Check if we've hit the end of this block. */
+	if (dev->sgd_sample_count <= 0) {
+		ac97_via_log("AC97 VIA: Ending SGD block");
+
+		/* Move on to the next block on the next poll. */
+		dev->sgd_entry_ptr += 8;
+
+		if (dev->sgd_entry & 0x2000000000000000ULL) {
+			ac97_via_log(" with STOP");
+			dev->sgd_regs[0x00] |= 0x04;
+		}
+		if (dev->sgd_entry & 0x4000000000000000ULL) {
+			ac97_via_log(" with FLAG");
+			dev->sgd_regs[0x00] |= 0x01;
+
+			/* Pause SGD. */
+			dev->sgd_regs[0x00] |= 0x04;
+
+			/* Fire interrupt if requested. */
+			if (dev->sgd_regs[0x02] & 0x01)
+				ac97_via_log(" interrupt");
+		}
+		if (dev->sgd_entry & 0x8000000000000000ULL) {
+			ac97_via_log(" with EOL");
+			dev->sgd_regs[0x00] |= 0x02;
+
+			/* Fire interrupt if requested. */
+			if (dev->sgd_regs[0x02] & 0x02)
+				ac97_via_log(" interrupt");
+
+			/* Restart SGD if a trigger is queued or auto-start is enabled. */
+			if ((dev->sgd_regs[0x00] & 0x08) || (dev->sgd_regs[0x02] & 0x80)) {
+				ac97_via_log(" restart\n");
+				dev->sgd_regs[0x00] &= ~0x08;
+
+				dev->sgd_entry_ptr = (dev->sgd_regs[0x07] << 24) | (dev->sgd_regs[0x06] << 16) | (dev->sgd_regs[0x05] << 8) | (dev->sgd_regs[0x04] & 0xfe);
+			} else {
+				ac97_via_log(" finish\n");
+				dev->sgd_regs[0x00] &= ~0x80;
+			}
+		} else {
+			ac97_via_log("\n");
+		}
+
+		dev->sgd_entry = dev->sgd_sample_count = 0;
+	}
+    } else {
+	dev->out_l = dev->out_r = 0;
+	dev->cd_vol_l = dev->cd_vol_r = 0;
+    }
+
+    if (dev->sgd_regs[0x00] & (dev->sgd_regs[0x02] & 0x03)) {
+	ac97_via_log("AC97 VIA: Setting IRQ (iflags %02X stuck %d)\n", dev->sgd_regs[0x00] & (dev->sgd_regs[0x02] & 0x03), dev->irq_stuck);
+	if (dev->irq_stuck) {
+		dev->losticount++;
+		pci_clear_irq(dev->slot, dev->irq_pin);
+	} else {
+		pci_set_irq(dev->slot, dev->irq_pin);
+	}
+	dev->irq_stuck = !dev->irq_stuck;
+    }
+}
+
+
+static void
+ac97_via_get_buffer(int32_t *buffer, int len, void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+
+    ac97_via_update(dev);
+
+    for (int c = 0; c < len * 2; c++) {
+	buffer[c] += dev->buffer[c];
+    }
+
+    dev->pos = 0;
+}
+
+
+static void
+ac97_via_speed_changed(void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    dev->timer_latch = (uint64_t) ((double) TIMER_USEC * (1000000.0 / 48000.0));
+}
+
+
+static void *
+ac97_via_init(const device_t *info)
+{
+    ac97_via_t *dev = malloc(sizeof(ac97_via_t));
+    memset(dev, 0, sizeof(ac97_via_t));
+
+    ac97_via_log("AC97 VIA: init()\n");
+
+    ac97_codec = &dev->codec[0];
+    ac97_modem_codec = &dev->codec[2];
+    ac97_codec_count = ac97_modem_codec_count = 2;
+
+    timer_add(&dev->timer_count, ac97_via_poll, dev, 0);
+    ac97_via_speed_changed(dev);
+    timer_advance_u64(&dev->timer_count, dev->timer_latch);
+
+    sound_add_handler(ac97_via_get_buffer, dev);
+
+    return dev;
+}
+
+
+static void
+ac97_via_close(void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+
+    ac97_via_log("AC97 VIA: close()\n");
+
+    free(dev);
+}
+
+
+const device_t ac97_via_device =
+{
+    "VIA VT82C686 AC97 Controller",
+    DEVICE_PCI,
+    0,
+    ac97_via_init, ac97_via_close, NULL,
+    { NULL },
+    ac97_via_speed_changed,
+    NULL,
+    NULL
+};
diff --git a/src/sound/snd_cs423x.c b/src/sound/snd_cs423x.c
index 7ea1deb65..03a258f30 100644
--- a/src/sound/snd_cs423x.c
+++ b/src/sound/snd_cs423x.c
@@ -19,7 +19,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <wchar.h>
-#include <math.h>  
+#include <math.h>
 #include <86box/86box.h>
 #include <86box/io.h>
 #include <86box/timer.h>
diff --git a/src/win/Makefile.mingw b/src/win/Makefile.mingw
index 3fa401f1e..47d5638bf 100644
--- a/src/win/Makefile.mingw
+++ b/src/win/Makefile.mingw
@@ -724,6 +724,7 @@ SNDOBJ		:= sound.o \
 		    snd_pssj.o \
 		    snd_lpt_dac.o snd_lpt_dss.o \
 		    snd_adlib.o snd_adlibgold.o snd_ad1848.o snd_audiopci.o \
+		    snd_ac97_codec.o snd_ac97_via.o \
 		    snd_azt2316a.o snd_cs423x.o \
 		    snd_cms.o \
 		    snd_gus.o \

From 2fa909ab91d3e0e46d0801d87c2a9d30d13e4a07 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 11 Jul 2021 17:04:41 -0300
Subject: [PATCH 04/52] Revert to the code which was working on XP

---
 src/sound/snd_ac97_via.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 3e83e20c2..b8d92fe8a 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -125,8 +125,8 @@ static void
 ac97_via_sgd_block_start(ac97_via_t *dev)
 {
     /* Start at first entry. */
-    /*if (!dev->sgd_entry_ptr)
-	dev->sgd_entry_ptr = (dev->sgd_regs[0x07] << 24) | (dev->sgd_regs[0x06] << 16) | (dev->sgd_regs[0x05] << 8) | (dev->sgd_regs[0x04] & 0xfe);*/
+    if (!dev->sgd_entry_ptr)
+	dev->sgd_entry_ptr = (dev->sgd_regs[0x07] << 24) | (dev->sgd_regs[0x06] << 16) | (dev->sgd_regs[0x05] << 8) | (dev->sgd_regs[0x04] & 0xfe);
 
     /* Read entry. */
     dev->sgd_entry = ((uint64_t) mem_readl_phys(dev->sgd_entry_ptr + 4) << 32ULL) | (uint64_t) mem_readl_phys(dev->sgd_entry_ptr);
@@ -291,7 +291,7 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 				dev->sgd_regs[0x00] &= ~0x44;
 
 				dev->sgd_entry = 0;
-				dev->sgd_entry_ptr = (dev->sgd_regs[0x07] << 24) | (dev->sgd_regs[0x06] << 16) | (dev->sgd_regs[0x05] << 8) | (dev->sgd_regs[0x04] & 0xfe);
+				dev->sgd_entry_ptr = 0;
 			}
 		}
 		/* Stop SGD if requested. */
@@ -465,7 +465,6 @@ static void
 ac97_via_poll(void *priv)
 {
     ac97_via_t *dev = (ac97_via_t *) priv;
-    uint8_t irq = 0;
 
     timer_advance_u64(&dev->timer_count, dev->timer_latch);
 
@@ -540,7 +539,7 @@ ac97_via_poll(void *priv)
 				ac97_via_log(" restart\n");
 				dev->sgd_regs[0x00] &= ~0x08;
 
-				dev->sgd_entry_ptr = (dev->sgd_regs[0x07] << 24) | (dev->sgd_regs[0x06] << 16) | (dev->sgd_regs[0x05] << 8) | (dev->sgd_regs[0x04] & 0xfe);
+				dev->sgd_entry_ptr = 0;
 			} else {
 				ac97_via_log(" finish\n");
 				dev->sgd_regs[0x00] &= ~0x80;

From 5bce2f09c7c7e7f2d3b3a816e4db831e820bdced Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 11 Jul 2021 17:12:48 -0300
Subject: [PATCH 05/52] Fix small oversight on codec shadow write

---
 src/sound/snd_ac97_via.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index b8d92fe8a..85e18b71b 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -417,7 +417,7 @@ ac97_via_codec_write(uint16_t addr, uint8_t val, void *priv)
     /* Bit 7 selects secondary codec. */
     ac97_codec_t *codec = dev->codec[(modem << 1) | (addr >> 7)];
     if (codec)
-	ac97_codec_write(codec, addr, val);
+	ac97_codec_write(codec, addr & 0x7f, val);
 }
 
 

From ff1a55d08d3a8be7160860971c4a6e48f51757eb Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 13 Jul 2021 00:53:26 -0300
Subject: [PATCH 06/52] More AC97, now with VIA kinda sorta working and ES1371

---
 src/chipset/via_pipc.c       |   4 +
 src/include/86box/snd_ac97.h |   1 +
 src/pci.c                    |   2 +-
 src/sound/snd_ac97_codec.c   |  15 +-
 src/sound/snd_ac97_via.c     | 610 +++++++++++++++++++----------------
 src/sound/snd_audiopci.c     |  86 ++---
 6 files changed, 402 insertions(+), 316 deletions(-)

diff --git a/src/chipset/via_pipc.c b/src/chipset/via_pipc.c
index 9ad32deca..95e900b5e 100644
--- a/src/chipset/via_pipc.c
+++ b/src/chipset/via_pipc.c
@@ -1125,6 +1125,10 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			gameport_remap(dev->gameport, (dev->ac97_regs[0][0x42] & 0x08) ? ((dev->ac97_regs[0][0x4b] << 8) | dev->ac97_regs[0][0x4a]) : 0);
 			break;
 
+		case 0x41:
+			dev->ac97_regs[func][addr] = val;
+			break;
+
 		case 0x43:
 			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val;
 			break;
diff --git a/src/include/86box/snd_ac97.h b/src/include/86box/snd_ac97.h
index 8d66cdea4..e0345227a 100644
--- a/src/include/86box/snd_ac97.h
+++ b/src/include/86box/snd_ac97.h
@@ -41,6 +41,7 @@ extern ac97_codec_t	**ac97_codec, **ac97_modem_codec;
 extern int		ac97_codec_count, ac97_modem_codec_count;
 
 extern const device_t	alc100_device;
+extern const device_t	cs4297a_device;
 
 extern const device_t	ac97_via_device;
 #endif
diff --git a/src/pci.c b/src/pci.c
index a4272e6bd..5f1c48f50 100644
--- a/src/pci.c
+++ b/src/pci.c
@@ -73,7 +73,7 @@ static int		trc_reg = 0;
 
 static void		pci_reset_regs(void);
 
-#define ENABLE_PCI_LOG 1
+
 #ifdef ENABLE_PCI_LOG
 int pci_do_log = ENABLE_PCI_LOG;
 
diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index e96795011..f97b1c551 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -29,7 +29,8 @@
 
 
 enum {
-    AC97_CODEC_ALC100 = AC97_CODEC_ID('A', 'L', 'C', 0x20)
+    AC97_CODEC_ALC100 = AC97_CODEC_ID('A', 'L', 'C', 0x20),
+    AC97_CODEC_CS4297A = AC97_CODEC_ID('C', 'R', 'Y', 0x11)
 };
 
 #define ENABLE_AC97_CODEC_LOG 1
@@ -225,3 +226,15 @@ const device_t alc100_device =
     NULL,
     NULL
 };
+
+const device_t cs4297a_device =
+{
+    "Crystal CS4297A",
+    DEVICE_AC97,
+    AC97_CODEC_CS4297A,
+    ac97_codec_init, ac97_codec_close, ac97_codec_reset,
+    { NULL },
+    NULL,
+    NULL,
+    NULL
+};
diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 85e18b71b..0ee33b94c 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -30,21 +30,29 @@
 #include <86box/sound.h>
 #include <86box/snd_ac97.h>
 
-#define SGD_UNPAUSED	(dev->sgd_regs[0x00] & 0xc4) == 0x80
-
 
 typedef struct {
+    uint8_t	id;
+    struct _ac97_via_ *dev;
+
+    uint64_t	entry;
+    uint32_t	entry_ptr, sample_ptr, fifo_pos, fifo_end;
+    int32_t	sample_count;
+    uint8_t	fifo[32];
+
+    pc_timer_t	timer;
+} ac97_via_sgd_t;
+
+typedef struct _ac97_via_ {
     uint16_t	audio_sgd_base, audio_codec_base, modem_sgd_base, modem_codec_base;
     uint8_t	sgd_regs[256], irq_stuck;
-    int		slot, irq_pin, losticount;
-    uint64_t	sgd_entry;
-    uint32_t	sgd_entry_ptr, sgd_sample_ptr;
-    int32_t	sgd_sample_count;
+    int		slot, irq_pin;
 
-    ac97_codec_t *codec[4];
+    ac97_codec_t *codec[2][2];
+    ac97_via_sgd_t sgd[6];
 
     pc_timer_t	timer_count;
-    uint64_t	timer_latch;
+    uint64_t	timer_latch, timer_fifo_latch;
     int16_t	out_l, out_r;
     double	cd_vol_l, cd_vol_r;
     int16_t	buffer[SOUNDBUFLEN * 2];
@@ -54,6 +62,7 @@ typedef struct {
 #define ENABLE_AC97_VIA_LOG 1
 #ifdef ENABLE_AC97_VIA_LOG
 int ac97_via_do_log = ENABLE_AC97_VIA_LOG;
+unsigned int ac97_via_lost_irqs = 0;
 
 static void
 ac97_via_log(const char *fmt, ...)
@@ -71,7 +80,7 @@ ac97_via_log(const char *fmt, ...)
 #endif
 
 
-static void	ac97_via_poll(void *priv);
+static void	ac97_via_sgd_process(void *priv);
 
 
 void
@@ -94,7 +103,7 @@ ac97_via_read_status(void *priv, uint8_t modem)
 
     /* Flag codecs as ready if present. */
     for (uint8_t i = 0; i <= 1; i++) {
-	if (dev->codec[(modem << 1) | i])
+	if (dev->codec[modem][i])
 		ret |= 0x01 << (i << 1);
     }
 
@@ -105,40 +114,32 @@ ac97_via_read_status(void *priv, uint8_t modem)
 
 
 static void
-ac97_via_sgd_startstop(ac97_via_t *dev)
+ac97_via_update_irqs(ac97_via_t *dev, uint8_t iflag_clear)
 {
-    /* Start polling timer if SGD is unpaused. */
-#if 0
-    if (SGD_UNPAUSED) {
-	ac97_via_log("AC97 VIA: Starting SGD at %08X\n", dev->sgd_entry_ptr);
-	timer_set_delay_u64(&dev->timer_count, dev->timer_latch);
-    } else {
-	ac97_via_log("AC97 VIA: Stopping SGD\n");
-	timer_disable(&dev->timer_count);
-	dev->out_l = dev->out_r = 0;
-    }
+    /* Check interrupt flags on all SGDs. */
+    for (uint8_t i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++) {
+    	if (dev->sgd_regs[i << 4] & (dev->sgd_regs[(i << 4) | 0x02] & 0x03)) {
+    		ac97_via_log("AC97 VIA: Setting IRQ (sgd %d iflags %02X stuck %d)\n",
+			     i, dev->sgd_regs[i << 4] & (dev->sgd_regs[(i << 4) | 0x02] & 0x03), dev->irq_stuck);
+
+    		if (dev->irq_stuck && !iflag_clear) {
+#ifdef ENABLE_AC97_VIA_LOG
+			ac97_via_lost_irqs++;
 #endif
-}
+			pci_clear_irq(dev->slot, dev->irq_pin);
+		} else {
+			pci_set_irq(dev->slot, dev->irq_pin);
+		}
+		dev->irq_stuck = !dev->irq_stuck;
 
+		return;
+    	}
+    }
 
-static void
-ac97_via_sgd_block_start(ac97_via_t *dev)
-{
-    /* Start at first entry. */
-    if (!dev->sgd_entry_ptr)
-	dev->sgd_entry_ptr = (dev->sgd_regs[0x07] << 24) | (dev->sgd_regs[0x06] << 16) | (dev->sgd_regs[0x05] << 8) | (dev->sgd_regs[0x04] & 0xfe);
-
-    /* Read entry. */
-    dev->sgd_entry = ((uint64_t) mem_readl_phys(dev->sgd_entry_ptr + 4) << 32ULL) | (uint64_t) mem_readl_phys(dev->sgd_entry_ptr);
-    if (dev->sgd_entry == 0xffffffffffffffffULL)
-	fatal("AC97 VIA: Invalid SGD entry at %08X\n", dev->sgd_entry_ptr);
-
-    /* Set sample pointer and count. */
-    dev->sgd_sample_ptr = dev->sgd_entry & 0xffffffff;
-    dev->sgd_sample_count = (dev->sgd_entry >> 32) & 0xffffff;
-
-    ac97_via_log("AC97 VIA: Starting SGD block at %08X entry %08X%08X (start %08X len %06X) losticount %d\n",
-		 dev->sgd_entry_ptr, mem_readl_phys(dev->sgd_entry_ptr + 4), mem_readl_phys(dev->sgd_entry_ptr), dev->sgd_sample_ptr, dev->sgd_sample_count, dev->losticount);
+    /* No interrupt pending. */
+    //ac97_via_log("AC97 VIA: Clearing IRQ\n");
+    pci_clear_irq(dev->slot, dev->irq_pin);
+    dev->irq_stuck = 0;
 }
 
 
@@ -148,78 +149,86 @@ ac97_via_sgd_read(uint16_t addr, void *priv)
     ac97_via_t *dev = (ac97_via_t *) priv;
     uint8_t modem = (addr & 0xff00) == dev->modem_sgd_base;
     addr &= 0xff;
-    uint8_t ret = 0x00;
+    uint8_t ret;
 
-    switch (addr) {
-	case 0x04:
-		ret = dev->sgd_entry_ptr;
-		break;
+    if (!(addr & 0x80)) {
+    	/* Process SGD channel registers. */
+    	switch (addr & 0xf) {
+    		case 0x4:
+			ret = dev->sgd[addr >> 4].entry_ptr;
+			break;
 
-	case 0x05:
-		ret = dev->sgd_entry_ptr >> 8;
-		break;
+		case 0x5:
+			ret = dev->sgd[addr >> 4].entry_ptr >> 8;
+			break;
 
-	case 0x06:
-		ret = dev->sgd_entry_ptr >> 16;
-		break;
+		case 0x6:
+			ret = dev->sgd[addr >> 4].entry_ptr >> 16;
+			break;
 
-	case 0x07:
-		ret = dev->sgd_entry_ptr >> 24;
-		/*pclog("sgd state %02X unpaused %d rct %02X\n", dev->sgd_regs[0x00], SGD_UNPAUSED, dev->sgd_regs[0x02]);
-		pci_clear_irq(dev->slot, dev->irq_pin);*/
-		break;
+		case 0x7:
+			ret = dev->sgd[addr >> 4].entry_ptr >> 24;
+			break;
 
-	case 0x0c:
-		ret = dev->sgd_sample_count;
-		break;
+		case 0xc:
+			ret = dev->sgd[addr >> 4].sample_count;
+			break;
 
-	case 0x0d:
-		ret = dev->sgd_sample_count >> 8;
-		break;
+		case 0xd:
+			ret = dev->sgd[addr >> 4].sample_count >> 8;
+			break;
 
-	case 0x0e:
-		ret = dev->sgd_sample_count >> 16;
-		break;
+		case 0xe:
+			ret = dev->sgd[addr >> 4].sample_count >> 16;
+			break;
 
-	case 0x84:
-		ret |= (dev->sgd_regs[0x00] & 0x01);
-		ret |= (dev->sgd_regs[0x10] & 0x01) << 1;
-		ret |= (dev->sgd_regs[0x20] & 0x01) << 2;
+		default:
+			ret = dev->sgd_regs[addr];
+			break;
+    	}
+    } else {
+    	/* Process regular registers. */
+	switch (addr) {
+		case 0x84:
+			ret  = (dev->sgd_regs[0x00] & 0x01);
+			ret |= (dev->sgd_regs[0x10] & 0x01) << 1;
+			ret |= (dev->sgd_regs[0x20] & 0x01) << 2;
 
-		ret |= (dev->sgd_regs[0x00] & 0x02) << 3;
-		ret |= (dev->sgd_regs[0x10] & 0x02) << 4;
-		ret |= (dev->sgd_regs[0x20] & 0x02) << 5;
-		break;
+			ret |= (dev->sgd_regs[0x00] & 0x02) << 3;
+			ret |= (dev->sgd_regs[0x10] & 0x02) << 4;
+			ret |= (dev->sgd_regs[0x20] & 0x02) << 5;
+			break;
 
-	case 0x85:
-		ret |= (dev->sgd_regs[0x00] & 0x04) >> 2;
-		ret |= (dev->sgd_regs[0x10] & 0x04) >> 1;
-		ret |= (dev->sgd_regs[0x20] & 0x04);
+		case 0x85:
+			ret  = (dev->sgd_regs[0x00] & 0x04) >> 2;
+			ret |= (dev->sgd_regs[0x10] & 0x04) >> 1;
+			ret |= (dev->sgd_regs[0x20] & 0x04);
 
-		ret |= (dev->sgd_regs[0x00] & 0x80) >> 3;
-		ret |= (dev->sgd_regs[0x10] & 0x80) >> 2;
-		ret |= (dev->sgd_regs[0x20] & 0x80) >> 1;
-		break;
+			ret |= (dev->sgd_regs[0x00] & 0x80) >> 3;
+			ret |= (dev->sgd_regs[0x10] & 0x80) >> 2;
+			ret |= (dev->sgd_regs[0x20] & 0x80) >> 1;
+			break;
 
-	case 0x86:
-		ret |= (dev->sgd_regs[0x40] & 0x01);
-		ret |= (dev->sgd_regs[0x50] & 0x01) << 1;
+		case 0x86:
+			ret  = (dev->sgd_regs[0x40] & 0x01);
+			ret |= (dev->sgd_regs[0x50] & 0x01) << 1;
 
-		ret |= (dev->sgd_regs[0x40] & 0x02) << 3;
-		ret |= (dev->sgd_regs[0x50] & 0x02) << 4;
-		break;
+			ret |= (dev->sgd_regs[0x40] & 0x02) << 3;
+			ret |= (dev->sgd_regs[0x50] & 0x02) << 4;
+			break;
 
-	case 0x87:
-		ret |= (dev->sgd_regs[0x40] & 0x04) >> 2;
-		ret |= (dev->sgd_regs[0x50] & 0x04) >> 1;
+		case 0x87:
+			ret  = (dev->sgd_regs[0x40] & 0x04) >> 2;
+			ret |= (dev->sgd_regs[0x50] & 0x04) >> 1;
 
-		ret |= (dev->sgd_regs[0x40] & 0x80) >> 3;
-		ret |= (dev->sgd_regs[0x50] & 0x80) >> 2;
-		break;
+			ret |= (dev->sgd_regs[0x40] & 0x80) >> 3;
+			ret |= (dev->sgd_regs[0x50] & 0x80) >> 2;
+			break;
 
-	default:
-		ret = dev->sgd_regs[addr];
-		break;
+		default:
+			ret = dev->sgd_regs[addr];
+			break;
+	}
     }
 
     ac97_via_log("AC97 VIA %d: sgd_read(%02X) = %02X\n", modem, addr, ret);
@@ -244,8 +253,8 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
     if (addr >= (modem ? 0x90 : 0x88))
 	return;
 
-    /* Check read-only registers for each SGD channel. */
     if (!(addr & 0x80)) {
+    	/* Process SGD channel registers. */
 	switch (addr & 0xf) {
 		case 0x0:
 			/* Clear RWC status bits. */
@@ -254,102 +263,102 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 					dev->sgd_regs[addr] &= ~i;
 			}
 
-			if (addr == 0x00) {
-				if (!(dev->sgd_regs[0x00] & (dev->sgd_regs[0x02] & 0x03))) {
-					ac97_via_log("AC97 VIA: Clearing IRQ (iflags %02X)\n", dev->sgd_regs[0x00] & (dev->sgd_regs[0x02] & 0x03));
-					pci_clear_irq(dev->slot, dev->irq_pin);
-					dev->irq_stuck = 0;
+			ac97_via_update_irqs(dev, 1);
+
+			return;
+
+		case 0x1:
+			/* Start SGD if requested. */
+			if (val & 0x80) {
+				if (dev->sgd_regs[addr & 0xf0] & 0x80) {
+					/* Queue SGD trigger. */
+					dev->sgd_regs[addr & 0xf0] |= 0x08;
+				} else {
+					/* Start SGD immediately. */
+					dev->sgd_regs[addr & 0xf0] |= 0x80;
+					dev->sgd_regs[addr & 0xf0] &= ~0x44;
+
+					/* Start at the specified entry pointer. */
+					dev->sgd[addr >> 4].entry = 0;
+					dev->sgd[addr >> 4].entry_ptr = (dev->sgd_regs[(addr & 0xf0) | 0x7] << 24) | (dev->sgd_regs[(addr & 0xf0) | 0x6] << 16) | (dev->sgd_regs[(addr & 0xf0) | 0x5] << 8) | (dev->sgd_regs[(addr & 0xf0) | 0x4] & 0xfe);
+
+					/* Start the actual SGD process. */
+					timer_advance_u64(&dev->sgd[addr >> 4].timer, 0);
 				}
-
-				/* Resume SGD if requested. */
-				if (val & 0x04)
-					ac97_via_sgd_startstop(dev);
 			}
+			/* Stop SGD if requested. */
+			if (val & 0x40)
+				dev->sgd_regs[addr & 0xf0] &= ~0x88;
 
-			/* fall-through */
+			val &= 0x04;
+
+			/* (Un)pause SGD if requested. */
+			if (val & 0x04)
+				dev->sgd_regs[addr & 0xf0] |= 0x40;
+			else
+				dev->sgd_regs[addr & 0xf0] &= ~0x40;
+
+			break;
+
+		case 0x2:
+			if (addr & 0x10)
+				val &= 0xf3;
+			break;
 
 		case 0x3: case 0x8 ... 0xf:
+			/* Read-only registers. */
 			return;
 	}
-    }
+    } else {
+    	/* Process regular registers. */
+	switch (addr) {
+		case 0x30 ... 0x3f:
+		case 0x60 ... 0x7f:
+		case 0x84 ... 0x87:
+			/* Read-only registers. */
+			return;
 
-    switch (addr) {
-	case 0x30 ... 0x3f:
-	case 0x60 ... 0x7f:
-		/* Read-only registers. */
-		return;
+		case 0x82:
+			/* Determine the selected codec. */
+			i = !!(dev->sgd_regs[0x83] & 0x40);
+			codec = dev->codec[modem][i];
 
-	case 0x01:
-		/* Start SGD if requested. */
-		if (val & 0x80) {
-			if (dev->sgd_regs[0x00] & 0x80) {
-				/* Queue SGD trigger. */
-				dev->sgd_regs[0x00] |= 0x08;
-			} else {
-				/* Start SGD immediately. */
-				dev->sgd_regs[0x00] |= 0x80;
-				dev->sgd_regs[0x00] &= ~0x44;
-
-				dev->sgd_entry = 0;
-				dev->sgd_entry_ptr = 0;
+			/* Read from or write to codec. */
+			if (codec) {
+				if (val & 0x80) {
+					val <<= 1;
+					dev->sgd_regs[0x80] = ac97_codec_read(codec, val);
+					dev->sgd_regs[0x81] = ac97_codec_read(codec, val | 1);
+				} else {
+					val <<= 1;
+					ac97_codec_write(codec, val, dev->sgd_regs[0x80]);
+					ac97_codec_write(codec, val | 1, dev->sgd_regs[0x81]);
+				}
+			} else if (val & 0x80) {
+				/* Unknown behavior when reading from a non-existent codec. */
+				dev->sgd_regs[0x80] = dev->sgd_regs[0x81] = 0xff;
 			}
-		}
-		/* Stop SGD if requested. */
-		if (val & 0x40) {
-			dev->sgd_regs[0x00] &= ~0x88;
-		}
 
-		val &= 0x04;
+			/* Flag data/status/index for this codec as valid. */
+			dev->sgd_regs[0x83] |= 0x02 << (i * 2);
+			break;
 
-		/* (Un)pause SGD if requested. */
-		if (val & 0x04)
-			dev->sgd_regs[0x00] |= 0x40;
-		else
-			dev->sgd_regs[0x00] &= ~0x40;
+		case 0x83:
+			val &= 0xca;
 
-		ac97_via_sgd_startstop(dev);
-		break;
-
-	case 0x82:
-		/* Determine the selected codec. */
-		i = !!(dev->sgd_regs[0x83] & 0x40);
-		codec = dev->codec[(modem << 1) | i];
-
-		/* Read from or write to codec. */
-		if (codec) {
-			if (val & 0x80) {
-				val <<= 1;
-				dev->sgd_regs[0x80] = ac97_codec_read(codec, val);
-				dev->sgd_regs[0x81] = ac97_codec_read(codec, val | 1);
-			} else {
-				val <<= 1;
-				ac97_codec_write(codec, val, dev->sgd_regs[0x80]);
-				ac97_codec_write(codec, val | 1, dev->sgd_regs[0x81]);
+			/* Clear RWC bits. */
+			for (i = 0x02; i <= 0x08; i <<= 2) {
+	#if 0 /* race condition with Linux clearing bits and starting SGD on the same dword write */
+				if (val & i)
+					val &= ~i;
+				else
+					val |= dev->sgd_regs[addr] & i;
+	#else
+				val |= i;
+	#endif
 			}
-		} else if (val & 0x80) {
-			/* Unknown behavior when reading from a non-existent codec. */
-			dev->sgd_regs[0x80] = dev->sgd_regs[0x81] = 0xff;
-		}
-
-		/* Flag data/status/index for this codec as valid. */
-		dev->sgd_regs[0x83] |= 0x02 << (i * 2);
-		break;
-
-	case 0x83:
-		val &= 0xca;
-
-		/* Clear RWC bits. */
-		for (i = 0x02; i <= 0x08; i <<= 2) {
-#if 0 /* race condition with Linux clearing bits and starting SGD on the same dword write */
-			if (val & i)
-				val &= ~i;
-			else
-				val |= dev->sgd_regs[addr] & i;
-#else
-			val |= i;
-#endif
-		}
-		break;
+			break;
+	}
     }
 
     dev->sgd_regs[addr] = val;
@@ -395,7 +404,7 @@ ac97_via_codec_read(uint16_t addr, void *priv)
     uint8_t ret = 0xff;
 
     /* Bit 7 selects secondary codec. */
-    ac97_codec_t *codec = dev->codec[(modem << 1) | (addr >> 7)];
+    ac97_codec_t *codec = dev->codec[modem][addr >> 7];
     if (codec)
 	ret = ac97_codec_read(codec, addr & 0x7f);
 
@@ -415,7 +424,7 @@ ac97_via_codec_write(uint16_t addr, uint8_t val, void *priv)
     ac97_via_log("AC97 VIA %d: codec_write(%02X, %02X)\n", modem, addr, val);
 
     /* Bit 7 selects secondary codec. */
-    ac97_codec_t *codec = dev->codec[(modem << 1) | (addr >> 7)];
+    ac97_codec_t *codec = dev->codec[modem][addr >> 7];
     if (codec)
 	ac97_codec_write(codec, addr & 0x7f, val);
 }
@@ -461,109 +470,151 @@ ac97_via_update(ac97_via_t *dev)
 }
 
 
+static void
+ac97_via_sgd_process(void *priv)
+{
+    ac97_via_sgd_t *sgd = (ac97_via_sgd_t *) priv;
+    ac97_via_t *dev = sgd->dev;
+
+    /* Process SGD if active, unless this is Audio Read and there's no room in the FIFO. */
+    if (((dev->sgd_regs[sgd->id] & 0xc4) == 0x80) && (sgd->id || ((sgd->fifo_end - sgd->fifo_pos) <= (sizeof(sgd->fifo) - 4)))) {
+    	/* Move on to the next block if no entry is present. */
+	if (!sgd->entry) {
+		/* Start at first entry if no pointer is present. */
+		if (!sgd->entry_ptr)
+			sgd->entry_ptr = (dev->sgd_regs[sgd->id | 0x7] << 24) | (dev->sgd_regs[sgd->id | 0x6] << 16) | (dev->sgd_regs[sgd->id | 0x5] << 8) | (dev->sgd_regs[sgd->id | 0x4] & 0xfe);
+
+		/* Read entry. */
+		sgd->entry = ((uint64_t) mem_readl_phys(sgd->entry_ptr + 4) << 32ULL) | (uint64_t) mem_readl_phys(sgd->entry_ptr);
+		if (sgd->entry == 0xffffffffffffffffULL)
+			fatal("AC97 VIA: Invalid SGD %d entry at %08X\n", sgd->id >> 4, sgd->entry_ptr);
+
+		/* Set sample pointer and count. */
+		sgd->sample_ptr = sgd->entry & 0xffffffff;
+		sgd->sample_count = (sgd->entry >> 32) & 0xffffff;
+
+		ac97_via_log("AC97 VIA: Starting SGD %d block at %08X entry %08X%08X (start %08X len %06X) lostirqs %d\n", sgd->id >> 4, sgd->entry_ptr,
+			     mem_readl_phys(sgd->entry_ptr + 4), mem_readl_phys(sgd->entry_ptr), sgd->sample_ptr, sgd->sample_count, ac97_via_lost_irqs);
+	}
+
+        if (sgd->id & 0x10) {
+        	/* Write channel: read data from FIFO. */
+        	mem_writel_phys(sgd->sample_ptr, *((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]));
+        } else {
+		/* Read channel: write data to FIFO. */
+		*((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]) = mem_readl_phys(sgd->sample_ptr);
+	}
+	sgd->fifo_end += 4;
+	sgd->sample_ptr += 4;
+	sgd->sample_count -= 4;
+
+	/* Check if we've hit the end of this block. */
+	if (sgd->sample_count <= 0) {
+		ac97_via_log("AC97 VIA: Ending SGD %d block", sgd->id >> 4);
+
+		/* Move on to the next block on the next run. */
+		sgd->entry_ptr += 8;
+
+		if (sgd->entry & 0x2000000000000000ULL) {
+			ac97_via_log(" with STOP");
+			dev->sgd_regs[sgd->id] |= 0x04;
+		}
+
+		if (sgd->entry & 0x4000000000000000ULL) {
+			ac97_via_log(" with FLAG");
+
+			/* Raise FLAG while also pausing SGD. */
+			dev->sgd_regs[sgd->id] |= 0x05;
+
+#ifdef ENABLE_AC97_VIA_LOG
+			if (dev->sgd_regs[sgd->id | 0x2] & 0x01)
+				ac97_via_log(" interrupt");
+#endif
+		}
+
+		if (sgd->entry & 0x8000000000000000ULL) {
+			ac97_via_log(" with EOL");
+
+			/* Raise EOL. */
+			dev->sgd_regs[sgd->id] |= 0x02;
+
+#ifdef ENABLE_AC97_VIA_LOG
+			if (dev->sgd_regs[sgd->id | 0x2] & 0x02)
+				ac97_via_log(" interrupt");
+#endif
+
+			/* Restart SGD if a trigger is queued or auto-start is enabled. */
+			if ((dev->sgd_regs[sgd->id] & 0x08) || (dev->sgd_regs[sgd->id | 0x2] & 0x80)) {
+				ac97_via_log(" restart");
+
+				/* Un-queue trigger. */
+				dev->sgd_regs[sgd->id] &= ~0x08;
+
+				/* Go back to the starting block. */
+				sgd->entry_ptr = 0;
+			} else {
+				ac97_via_log(" finish");
+
+				/* Terminate SGD. */
+				dev->sgd_regs[sgd->id] &= ~0x80;
+			}
+		}
+		ac97_via_log("\n");
+
+		/* Start a new block. */
+		sgd->entry = sgd->sample_count = 0;
+	}
+    }
+
+    ac97_via_update_irqs(dev, 0);
+
+    /* Continue SGD processing if active or an interrupt is pending. */
+    if (dev->sgd_regs[sgd->id] & (0x80 | (dev->sgd_regs[sgd->id | 0x02] & 0x03)))
+	timer_advance_u64(&sgd->timer, dev->timer_fifo_latch);
+}
+
+
 static void
 ac97_via_poll(void *priv)
 {
     ac97_via_t *dev = (ac97_via_t *) priv;
+    ac97_via_sgd_t *sgd = &dev->sgd[0]; /* Audio Read */
 
     timer_advance_u64(&dev->timer_count, dev->timer_latch);
 
     ac97_via_update(dev);
 
-    /* Read only if SGD is active and not paused. */
-    if (SGD_UNPAUSED) {
-	if (!dev->sgd_entry) {
-		/* Move on to the next block. */
-		ac97_via_sgd_block_start(dev);
-	}
+    dev->out_l = dev->out_r = 0;
 
-	switch (dev->sgd_regs[0x02] & 0x30) {
-		case 0x00: /* Mono, 8-bit PCM */
-			dev->out_l = dev->out_r = (mem_readb_phys(dev->sgd_sample_ptr++) ^ 0x80) * 256;
-			dev->sgd_sample_count--;
-			break;
+    switch (dev->sgd_regs[0x02] & 0x30) {
+	case 0x00: /* Mono, 8-bit PCM */
+		if ((sgd->fifo_end - sgd->fifo_pos) >= 1)
+			dev->out_l = dev->out_r = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+		break;
 
-		case 0x10: /* Stereo, 8-bit PCM */
-			dev->out_l = (mem_readb_phys(dev->sgd_sample_ptr++) ^ 0x80) * 256;
-			dev->out_r = (mem_readb_phys(dev->sgd_sample_ptr++) ^ 0x80) * 256;
-			dev->sgd_sample_count -= 2;
-			break;
-
-		case 0x20: /* Mono, 16-bit PCM */
-			dev->out_l = dev->out_r = mem_readw_phys(dev->sgd_sample_ptr);
-			dev->sgd_sample_ptr += 2;
-			dev->sgd_sample_count -= 2;
-			break;
-
-		case 0x30: /* Stereo, 16-bit PCM */
-			dev->out_l = mem_readw_phys(dev->sgd_sample_ptr);
-			dev->sgd_sample_ptr += 2;
-			dev->out_r = mem_readw_phys(dev->sgd_sample_ptr);
-			dev->sgd_sample_ptr += 2;
-			dev->sgd_sample_count -= 4;
-			break;
-	}
-
-	/* Check if we've hit the end of this block. */
-	if (dev->sgd_sample_count <= 0) {
-		ac97_via_log("AC97 VIA: Ending SGD block");
-
-		/* Move on to the next block on the next poll. */
-		dev->sgd_entry_ptr += 8;
-
-		if (dev->sgd_entry & 0x2000000000000000ULL) {
-			ac97_via_log(" with STOP");
-			dev->sgd_regs[0x00] |= 0x04;
+	case 0x10: /* Stereo, 8-bit PCM */
+		if ((sgd->fifo_end - sgd->fifo_pos) >= 2) {
+			dev->out_l = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+			dev->out_r = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
 		}
-		if (dev->sgd_entry & 0x4000000000000000ULL) {
-			ac97_via_log(" with FLAG");
-			dev->sgd_regs[0x00] |= 0x01;
+		break;
 
-			/* Pause SGD. */
-			dev->sgd_regs[0x00] |= 0x04;
-
-			/* Fire interrupt if requested. */
-			if (dev->sgd_regs[0x02] & 0x01)
-				ac97_via_log(" interrupt");
+	case 0x20: /* Mono, 16-bit PCM */
+		if ((sgd->fifo_end - sgd->fifo_pos) >= 2) {
+			dev->out_l = dev->out_r = *((uint16_t *) &sgd->fifo[sgd->fifo_pos & (sizeof(sgd->fifo) - 1)]);
+			sgd->fifo_pos += 2;
 		}
-		if (dev->sgd_entry & 0x8000000000000000ULL) {
-			ac97_via_log(" with EOL");
-			dev->sgd_regs[0x00] |= 0x02;
+		break;
 
-			/* Fire interrupt if requested. */
-			if (dev->sgd_regs[0x02] & 0x02)
-				ac97_via_log(" interrupt");
-
-			/* Restart SGD if a trigger is queued or auto-start is enabled. */
-			if ((dev->sgd_regs[0x00] & 0x08) || (dev->sgd_regs[0x02] & 0x80)) {
-				ac97_via_log(" restart\n");
-				dev->sgd_regs[0x00] &= ~0x08;
-
-				dev->sgd_entry_ptr = 0;
-			} else {
-				ac97_via_log(" finish\n");
-				dev->sgd_regs[0x00] &= ~0x80;
-			}
-		} else {
-			ac97_via_log("\n");
+	case 0x30: /* Stereo, 16-bit PCM */
+		pclog("fifo_end - fifo_pos = %d\n", sgd->fifo_end - sgd->fifo_pos);
+		if ((sgd->fifo_end - sgd->fifo_pos) >= 4) {
+			dev->out_l = *((uint16_t *) &sgd->fifo[sgd->fifo_pos & (sizeof(sgd->fifo) - 1)]);
+			sgd->fifo_pos += 2;
+			dev->out_r = *((uint16_t *) &sgd->fifo[sgd->fifo_pos & (sizeof(sgd->fifo) - 1)]);
+			sgd->fifo_pos += 2;
 		}
-
-		dev->sgd_entry = dev->sgd_sample_count = 0;
-	}
-    } else {
-	dev->out_l = dev->out_r = 0;
-	dev->cd_vol_l = dev->cd_vol_r = 0;
-    }
-
-    if (dev->sgd_regs[0x00] & (dev->sgd_regs[0x02] & 0x03)) {
-	ac97_via_log("AC97 VIA: Setting IRQ (iflags %02X stuck %d)\n", dev->sgd_regs[0x00] & (dev->sgd_regs[0x02] & 0x03), dev->irq_stuck);
-	if (dev->irq_stuck) {
-		dev->losticount++;
-		pci_clear_irq(dev->slot, dev->irq_pin);
-	} else {
-		pci_set_irq(dev->slot, dev->irq_pin);
-	}
-	dev->irq_stuck = !dev->irq_stuck;
+		break;
     }
 }
 
@@ -575,9 +626,8 @@ ac97_via_get_buffer(int32_t *buffer, int len, void *priv)
 
     ac97_via_update(dev);
 
-    for (int c = 0; c < len * 2; c++) {
+    for (int c = 0; c < len * 2; c++)
 	buffer[c] += dev->buffer[c];
-    }
 
     dev->pos = 0;
 }
@@ -588,6 +638,7 @@ ac97_via_speed_changed(void *priv)
 {
     ac97_via_t *dev = (ac97_via_t *) priv;
     dev->timer_latch = (uint64_t) ((double) TIMER_USEC * (1000000.0 / 48000.0));
+    dev->timer_fifo_latch = (uint64_t) ((double) TIMER_USEC * 10.0);
 }
 
 
@@ -599,14 +650,25 @@ ac97_via_init(const device_t *info)
 
     ac97_via_log("AC97 VIA: init()\n");
 
-    ac97_codec = &dev->codec[0];
-    ac97_modem_codec = &dev->codec[2];
-    ac97_codec_count = ac97_modem_codec_count = 2;
+    /* Set up codecs. */
+    ac97_codec = &dev->codec[0][0];
+    ac97_modem_codec = &dev->codec[1][0];
+    ac97_codec_count = ac97_modem_codec_count = sizeof(dev->codec[0]) / sizeof(dev->codec[0][0]);
 
+    /* Set up SGD channels. */
+    for (uint8_t i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++) {
+    	dev->sgd[i].id = i << 4;
+    	dev->sgd[i].dev = dev;
+
+    	timer_add(&dev->sgd[i].timer, ac97_via_sgd_process, &dev->sgd[i], 0);
+    }
+
+    /* Set up playback poller. */
     timer_add(&dev->timer_count, ac97_via_poll, dev, 0);
     ac97_via_speed_changed(dev);
     timer_advance_u64(&dev->timer_count, dev->timer_latch);
 
+    /* Set up playback handler. */
     sound_add_handler(ac97_via_get_buffer, dev);
 
     return dev;
@@ -626,7 +688,7 @@ ac97_via_close(void *priv)
 
 const device_t ac97_via_device =
 {
-    "VIA VT82C686 AC97 Controller",
+    "VIA VT82C686 Integrated AC97 Controller",
     DEVICE_PCI,
     0,
     ac97_via_init, ac97_via_close, NULL,
diff --git a/src/sound/snd_audiopci.c b/src/sound/snd_audiopci.c
index 1c697a3a8..9c65052f0 100644
--- a/src/sound/snd_audiopci.c
+++ b/src/sound/snd_audiopci.c
@@ -17,6 +17,7 @@
 #include <86box/sound.h>
 #include <86box/midi.h>
 #include <86box/snd_mpu401.h>
+#include <86box/snd_ac97.h>
 
 
 #define N 16
@@ -51,7 +52,7 @@ typedef struct {
     uint8_t uart_ctrl;
     uint8_t uart_status;
 
-    uint16_t codec_regs[128];
+    ac97_codec_t *codec;
     uint32_t codec_ctrl;
 
     struct {
@@ -358,11 +359,7 @@ static uint32_t es1371_inl(uint16_t port, void *p)
 		break;
 		
 		case 0x14:
-		ret = es1371->codec_ctrl & 0x00ff0000;
-		ret |= es1371->codec_regs[(es1371->codec_ctrl >> 16) & 0x7f];
-		if (((es1371->codec_ctrl >> 16) & 0x7f) == 0x26)
-			ret |= 0x0f;
-		ret |= CODEC_READY;
+		ret = es1371->codec_ctrl | CODEC_READY;
 		break;
 
 		case 0x30:
@@ -593,39 +590,48 @@ static void es1371_outl(uint16_t port, uint32_t val, void *p)
 		break;
 
 		case 0x14:
-		es1371->codec_ctrl = val;
-		if (!(val & CODEC_READ))
-		{
-//			audiopci_log("Write codec %02x %04x\n", (val >> 16) & 0x7f, val & 0xffff);
-			if ((((val >> 16) & 0x7f) != 0x7c) && (((val >> 16) & 0x7f) != 0x7e))
-				es1371->codec_regs[(val >> 16) & 0x7f] = val & 0xffff;
-			switch ((val >> 16) & 0x7f)
-			{
-				case 0x02: /*Master volume*/
-				if (val & 0x8000)
-					es1371->master_vol_l = es1371->master_vol_r = 0;
-				else
-				{
-					if (val & 0x2000)
+		if (val & CODEC_READ) {
+			es1371->codec_ctrl &= 0x00ff0000;
+			es1371->codec_ctrl |= ac97_codec_read(es1371->codec, (val >> 16) & 0x7f);
+			es1371->codec_ctrl |= ac97_codec_read(es1371->codec, ((val >> 16) & 0x7f) + 1) << 8;
+		} else {
+			es1371->codec_ctrl &= 0x00ffffff;
+			ac97_codec_write(es1371->codec, (val >> 16) & 0x7f, val & 0xff);
+			ac97_codec_write(es1371->codec, ((val >> 16) & 0x7f) + 1, val >> 8);
+
+			switch ((val >> 16) & 0x7f) {
+				case 0x02: /* Master Volume LSB */
+					if (es1371->codec->regs[0x03] & 0x80)
+						es1371->master_vol_l = es1371->master_vol_r = 0;
+					else if (val & 0x20)
+						es1371->master_vol_r = codec_attn[0];
+					else
+						es1371->master_vol_r = codec_attn[0x1f - (val & 0x1f)];
+					break;
+
+				case 0x03: /* Master Volume MSB */
+					if (val & 0x80)
+						es1371->master_vol_l = es1371->master_vol_r = 0;
+					else if (val & 0x20)
 						es1371->master_vol_l = codec_attn[0];
 					else
-						es1371->master_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
-					if (val & 0x20)
-						es1371->master_vol_r = codec_attn[0];
-					else					
-						es1371->master_vol_r = codec_attn[0x1f - (val & 0x1f)];
-				}
-				break;
-				case 0x12: /*CD volume*/
-				if (val & 0x8000)
-					es1371->cd_vol_l = es1371->cd_vol_r = 0;
-				else
-				{
-					es1371->cd_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
-					es1371->cd_vol_r = codec_attn[0x1f - (val & 0x1f)];
-				}
-				break;
-			}       
+						es1371->master_vol_l = codec_attn[0x1f - (val & 0x1f)];
+					break;
+
+				case 0x12: /* CD Volume LSB */
+					if (es1371->codec->regs[0x13] & 0x80)
+						es1371->cd_vol_l = es1371->cd_vol_r = 0;
+					else
+						es1371->cd_vol_r = codec_attn[0x1f - (val & 0x1f)];
+					break;
+
+				case 0x13: /* CD Volume MSB */
+					if (val & 0x80)
+						es1371->cd_vol_l = es1371->cd_vol_r = 0;
+					else
+						es1371->cd_vol_l = codec_attn[0x1f - (val & 0x1f)];
+					break;
+			}
 		}
 		break;
 		
@@ -1362,9 +1368,9 @@ static void *es1371_init(const device_t *info)
         
         generate_es1371_filter();
 
-	/* Return a CS4297A like VMware does. */
-	es1371->codec_regs[0x7c] = 0x4352;
-	es1371->codec_regs[0x7e] = 0x5910;
+	ac97_codec = &es1371->codec;
+	ac97_codec_count = 1;
+	device_add(&cs4297a_device);
 
 	return es1371;
 }

From b14e20b3fbed835c6fb34f435f65f264ae297612 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 13 Jul 2021 21:15:25 -0300
Subject: [PATCH 07/52] Fix AC97 codec ID byte ordering

---
 src/sound/snd_ac97_codec.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index f97b1c551..0074a9601 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -90,7 +90,7 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 	//case 0x2a ... 0x59: /* Linux tests for audio capability by writing to 38-39 */
 	case 0x5a ... 0x5f: /* Vendor Reserved */
 	//case 0x60 ... 0x6f:
-	case 0x70 ... 0x7b: /* Vendor Reserved */
+	case 0x70 ... 0x7f: /* Vendor Reserved */
 		/* Read-only registers. */
 		return;
 
@@ -175,8 +175,8 @@ ac97_codec_reset(void *priv)
     /* Set Vendor ID. */
     dev->regs[0x7c] = dev->id >> 16;
     dev->regs[0x7d] = dev->id >> 24;
-    dev->regs[0x7e] = dev->id >> 8;
-    dev->regs[0x7f] = dev->id;
+    dev->regs[0x7e] = dev->id;
+    dev->regs[0x7f] = dev->id >> 8;
 }
 
 

From 07c449ada1163400c58eb605484d9966a35c6f39 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 13 Jul 2021 21:16:08 -0300
Subject: [PATCH 08/52] Fix ES1371 codec writes and add I/O fallbacks, Linux
 now outputs.

---
 src/sound/snd_audiopci.c | 54 +++++++++++++++++++---------------------
 1 file changed, 25 insertions(+), 29 deletions(-)

diff --git a/src/sound/snd_audiopci.c b/src/sound/snd_audiopci.c
index 9c65052f0..ee529c59f 100644
--- a/src/sound/snd_audiopci.c
+++ b/src/sound/snd_audiopci.c
@@ -333,7 +333,8 @@ static uint16_t es1371_inw(uint16_t port, void *p)
 		break;
 
 		default:
-		audiopci_log("Bad es1371_inw: port=%04x\n", port);
+		ret  = es1371_inb(port, p);
+		ret |= es1371_inb(port + 1, p) << 8;
 	}
 
 //	audiopci_log("es1371_inw: port=%04x ret=%04x %04x:%08x\n", port, ret, CS,cpu_state.pc);
@@ -413,7 +414,8 @@ static uint32_t es1371_inl(uint16_t port, void *p)
 		break;
 		
 		default:
-		audiopci_log("Bad es1371_inl: port=%04x\n", port);
+		ret  = es1371_inw(port, p);
+		ret |= es1371_inw(port + 2, p) << 16;
 	}
 
 	audiopci_log("es1371_inl: port=%04x ret=%08x\n", port, ret);
@@ -524,7 +526,8 @@ static void es1371_outw(uint16_t port, uint16_t val, void *p)
 		break;
 		
 		default:
-		audiopci_log("Bad es1371_outw: port=%04x val=%04x\n", port, val);
+		es1371_outb(port, val & 0xff, p);
+		es1371_outb(port + 1, (val >> 8) & 0xff, p);
 	}
 }
 static void es1371_outl(uint16_t port, uint32_t val, void *p)
@@ -600,36 +603,28 @@ static void es1371_outl(uint16_t port, uint32_t val, void *p)
 			ac97_codec_write(es1371->codec, ((val >> 16) & 0x7f) + 1, val >> 8);
 
 			switch ((val >> 16) & 0x7f) {
-				case 0x02: /* Master Volume LSB */
-					if (es1371->codec->regs[0x03] & 0x80)
+				case 0x02: /* Master Volume */
+					if (val & 0x8000) {
 						es1371->master_vol_l = es1371->master_vol_r = 0;
-					else if (val & 0x20)
-						es1371->master_vol_r = codec_attn[0];
-					else
-						es1371->master_vol_r = codec_attn[0x1f - (val & 0x1f)];
+					} else {
+						if (val & 0x2000)
+							es1371->master_vol_l = codec_attn[0];
+						else
+							es1371->master_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
+						if (val & 0x20)
+							es1371->master_vol_r = codec_attn[0];
+						else
+							es1371->master_vol_r = codec_attn[0x1f - (val & 0x1f)];
+					}
 					break;
 
-				case 0x03: /* Master Volume MSB */
-					if (val & 0x80)
-						es1371->master_vol_l = es1371->master_vol_r = 0;
-					else if (val & 0x20)
-						es1371->master_vol_l = codec_attn[0];
-					else
-						es1371->master_vol_l = codec_attn[0x1f - (val & 0x1f)];
-					break;
-
-				case 0x12: /* CD Volume LSB */
-					if (es1371->codec->regs[0x13] & 0x80)
+				case 0x12: /* CD Volume */
+					if (val & 0x8000) {
 						es1371->cd_vol_l = es1371->cd_vol_r = 0;
-					else
+					} else {
+						es1371->cd_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
 						es1371->cd_vol_r = codec_attn[0x1f - (val & 0x1f)];
-					break;
-
-				case 0x13: /* CD Volume MSB */
-					if (val & 0x80)
-						es1371->cd_vol_l = es1371->cd_vol_r = 0;
-					else
-						es1371->cd_vol_l = codec_attn[0x1f - (val & 0x1f)];
+					}
 					break;
 			}
 		}
@@ -736,7 +731,8 @@ static void es1371_outl(uint16_t port, uint32_t val, void *p)
 		break;
 
 		default:
-		audiopci_log("Bad es1371_outl: port=%04x val=%08x\n", port, val);
+		es1371_outw(port, val & 0xffff, p);
+		es1371_outw(port + 2, (val >> 16) & 0xffff, p);
 	}
 }
 

From 67dfb363c13c211d73171d7a2360181492d51c9f Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 13 Jul 2021 21:16:43 -0300
Subject: [PATCH 09/52] 6VIA90AP *should* have the ALC100 codec

---
 src/machine/m_at_socket370.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/machine/m_at_socket370.c b/src/machine/m_at_socket370.c
index cc2e1718a..14f5e0dca 100644
--- a/src/machine/m_at_socket370.c
+++ b/src/machine/m_at_socket370.c
@@ -452,9 +452,7 @@ machine_at_6via90ap_init(const machine_t *model)
     hwm_values.temperatures[1] += 2; /* System offset */
     hwm_values.temperatures[2] = 0; /* unused */
 
-    /* I recall identifying this board's codec as the ALC100 while studying AC97, but I couldn't find
-       that information again. Other Acorp boards have the ALC100, though, so it's a safe bet. -RG */
-    device_add(&alc100_device);
+    device_add(&alc100_device); /* ALC100P identified on similar Acorp boards (694TA, 6VIA90A1) */
 
     return ret;
 }

From 9643bbd5793ae25469077fb5289f32710f0c8af6 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 13 Jul 2021 22:06:17 -0300
Subject: [PATCH 10/52] Add AC97 audio to VA-503A

---
 src/include/86box/snd_ac97.h |  1 +
 src/machine/m_at_sockets7.c  |  5 ++++-
 src/sound/snd_ac97_codec.c   | 15 ++++++++++++++-
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/src/include/86box/snd_ac97.h b/src/include/86box/snd_ac97.h
index e0345227a..9c4bd308a 100644
--- a/src/include/86box/snd_ac97.h
+++ b/src/include/86box/snd_ac97.h
@@ -42,6 +42,7 @@ extern int		ac97_codec_count, ac97_modem_codec_count;
 
 extern const device_t	alc100_device;
 extern const device_t	cs4297a_device;
+extern const device_t	wm9701a_device;
 
 extern const device_t	ac97_via_device;
 #endif
diff --git a/src/machine/m_at_sockets7.c b/src/machine/m_at_sockets7.c
index f15ddf01b..ca6c957e2 100644
--- a/src/machine/m_at_sockets7.c
+++ b/src/machine/m_at_sockets7.c
@@ -40,6 +40,7 @@
 #include <86box/video.h>
 #include "cpu.h"
 #include <86box/machine.h>
+#include <86box/snd_ac97.h>
 
 
 int
@@ -112,7 +113,7 @@ machine_at_ficva503a_init(const machine_t *model)
 {
     int ret;
 
-    ret = bios_load_linear("roms/machines/ficva503a/jo4116.bin",
+    ret = bios_load_linear("roms/machines/ficva503a/jn4116.bin",
 			   0x000c0000, 262144, 0);
 
     if (bios_only || !ret)
@@ -140,5 +141,7 @@ machine_at_ficva503a_init(const machine_t *model)
     hwm_values.temperatures[1] += 2; /* System offset */
     hwm_values.temperatures[2] = 0; /* unused */
 
+    device_add(&wm9701a_device); /* on daughtercard */
+
     return ret;
 }
diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index 0074a9601..57083d590 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -30,7 +30,8 @@
 
 enum {
     AC97_CODEC_ALC100 = AC97_CODEC_ID('A', 'L', 'C', 0x20),
-    AC97_CODEC_CS4297A = AC97_CODEC_ID('C', 'R', 'Y', 0x11)
+    AC97_CODEC_CS4297A = AC97_CODEC_ID('C', 'R', 'Y', 0x11),
+    AC97_CODEC_WM9701A = AC97_CODEC_ID('W', 'M', 'L', 0x00)
 };
 
 #define ENABLE_AC97_CODEC_LOG 1
@@ -238,3 +239,15 @@ const device_t cs4297a_device =
     NULL,
     NULL
 };
+
+const device_t wm9701a_device =
+{
+    "Wolfson WM9701A",
+    DEVICE_AC97,
+    AC97_CODEC_WM9701A,
+    ac97_codec_init, ac97_codec_close, ac97_codec_reset,
+    { NULL },
+    NULL,
+    NULL,
+    NULL
+};

From a976256b1e455484bcab376b7d8eba9d48484303 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 13 Jul 2021 22:14:39 -0300
Subject: [PATCH 11/52] VIA AC97 updates: Linux now kinda works

---
 src/sound/snd_ac97_via.c | 44 ++++++++++++++++++++++------------------
 1 file changed, 24 insertions(+), 20 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 0ee33b94c..65b2f889e 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -101,7 +101,7 @@ ac97_via_read_status(void *priv, uint8_t modem)
     ac97_via_t *dev = (ac97_via_t *) priv;
     uint8_t ret = 0x00;
 
-    /* Flag codecs as ready if present. */
+    /* Flag each codec as ready if present. */
     for (uint8_t i = 0; i <= 1; i++) {
 	if (dev->codec[modem][i])
 		ret |= 0x01 << (i << 1);
@@ -326,21 +326,19 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 			/* Read from or write to codec. */
 			if (codec) {
 				if (val & 0x80) {
-					val <<= 1;
-					dev->sgd_regs[0x80] = ac97_codec_read(codec, val);
-					dev->sgd_regs[0x81] = ac97_codec_read(codec, val | 1);
+					dev->sgd_regs[0x80] = ac97_codec_read(codec, val & 0x7e);
+					dev->sgd_regs[0x81] = ac97_codec_read(codec, (val & 0x7e) | 1);
 				} else {
-					val <<= 1;
-					ac97_codec_write(codec, val, dev->sgd_regs[0x80]);
-					ac97_codec_write(codec, val | 1, dev->sgd_regs[0x81]);
+					ac97_codec_write(codec, val & 0x7e, dev->sgd_regs[0x80]);
+					ac97_codec_write(codec, (val & 0x7e) | 1, dev->sgd_regs[0x81]);
 				}
+
+				/* Flag data/status/index for this codec as valid. */
+				dev->sgd_regs[0x83] |= 0x02 << (i * 2);
 			} else if (val & 0x80) {
-				/* Unknown behavior when reading from a non-existent codec. */
+				/* Unknown behavior when reading from an absent codec. */
 				dev->sgd_regs[0x80] = dev->sgd_regs[0x81] = 0xff;
 			}
-
-			/* Flag data/status/index for this codec as valid. */
-			dev->sgd_regs[0x83] |= 0x02 << (i * 2);
 			break;
 
 		case 0x83:
@@ -348,14 +346,18 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 
 			/* Clear RWC bits. */
 			for (i = 0x02; i <= 0x08; i <<= 2) {
-	#if 0 /* race condition with Linux clearing bits and starting SGD on the same dword write */
+#if 0 /* race condition with Linux clearing bits and starting SGD on the same dword write */
 				if (val & i)
 					val &= ~i;
 				else
 					val |= dev->sgd_regs[addr] & i;
-	#else
-				val |= i;
-	#endif
+#else
+				/* Don't flag data/status/index as valid if the codec is absent. */
+				if (dev->codec[modem][!!(val & 0x40)])
+					val |= i;
+				else
+					val &= ~i;
+#endif
 			}
 			break;
 	}
@@ -486,8 +488,10 @@ ac97_via_sgd_process(void *priv)
 
 		/* Read entry. */
 		sgd->entry = ((uint64_t) mem_readl_phys(sgd->entry_ptr + 4) << 32ULL) | (uint64_t) mem_readl_phys(sgd->entry_ptr);
+#ifdef ENABLE_AC97_VIA_LOG
 		if (sgd->entry == 0xffffffffffffffffULL)
 			fatal("AC97 VIA: Invalid SGD %d entry at %08X\n", sgd->id >> 4, sgd->entry_ptr);
+#endif
 
 		/* Set sample pointer and count. */
 		sgd->sample_ptr = sgd->entry & 0xffffffff;
@@ -495,6 +499,9 @@ ac97_via_sgd_process(void *priv)
 
 		ac97_via_log("AC97 VIA: Starting SGD %d block at %08X entry %08X%08X (start %08X len %06X) lostirqs %d\n", sgd->id >> 4, sgd->entry_ptr,
 			     mem_readl_phys(sgd->entry_ptr + 4), mem_readl_phys(sgd->entry_ptr), sgd->sample_ptr, sgd->sample_count, ac97_via_lost_irqs);
+
+		/* Increment entry pointer now, as Linux expects it to be one block ahead. */
+		sgd->entry_ptr += 8;
 	}
 
         if (sgd->id & 0x10) {
@@ -512,9 +519,6 @@ ac97_via_sgd_process(void *priv)
 	if (sgd->sample_count <= 0) {
 		ac97_via_log("AC97 VIA: Ending SGD %d block", sgd->id >> 4);
 
-		/* Move on to the next block on the next run. */
-		sgd->entry_ptr += 8;
-
 		if (sgd->entry & 0x2000000000000000ULL) {
 			ac97_via_log(" with STOP");
 			dev->sgd_regs[sgd->id] |= 0x04;
@@ -561,7 +565,7 @@ ac97_via_sgd_process(void *priv)
 		}
 		ac97_via_log("\n");
 
-		/* Start a new block. */
+		/* Move on to a new block on the next run. */
 		sgd->entry = sgd->sample_count = 0;
 	}
     }
@@ -586,6 +590,7 @@ ac97_via_poll(void *priv)
 
     dev->out_l = dev->out_r = 0;
 
+    pclog("fifo_end - fifo_pos = %d\n", sgd->fifo_end - sgd->fifo_pos);
     switch (dev->sgd_regs[0x02] & 0x30) {
 	case 0x00: /* Mono, 8-bit PCM */
 		if ((sgd->fifo_end - sgd->fifo_pos) >= 1)
@@ -607,7 +612,6 @@ ac97_via_poll(void *priv)
 		break;
 
 	case 0x30: /* Stereo, 16-bit PCM */
-		pclog("fifo_end - fifo_pos = %d\n", sgd->fifo_end - sgd->fifo_pos);
 		if ((sgd->fifo_end - sgd->fifo_pos) >= 4) {
 			dev->out_l = *((uint16_t *) &sgd->fifo[sgd->fifo_pos & (sizeof(sgd->fifo) - 1)]);
 			sgd->fifo_pos += 2;

From 292874f772664fc82413e342d60f83a7a5550b99 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Fri, 16 Jul 2021 15:39:19 -0300
Subject: [PATCH 12/52] Fix unused variable warning with logging disabled

---
 src/sound/snd_ac97_via.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 65b2f889e..382978526 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -59,7 +59,7 @@ typedef struct _ac97_via_ {
     int		pos;
 } ac97_via_t;
 
-#define ENABLE_AC97_VIA_LOG 1
+//#define ENABLE_AC97_VIA_LOG 1
 #ifdef ENABLE_AC97_VIA_LOG
 int ac97_via_do_log = ENABLE_AC97_VIA_LOG;
 unsigned int ac97_via_lost_irqs = 0;
@@ -147,7 +147,9 @@ uint8_t
 ac97_via_sgd_read(uint16_t addr, void *priv)
 {
     ac97_via_t *dev = (ac97_via_t *) priv;
+#ifdef ENABLE_AC97_VIA_LOG
     uint8_t modem = (addr & 0xff00) == dev->modem_sgd_base;
+#endif
     addr &= 0xff;
     uint8_t ret;
 
@@ -590,7 +592,7 @@ ac97_via_poll(void *priv)
 
     dev->out_l = dev->out_r = 0;
 
-    pclog("fifo_end - fifo_pos = %d\n", sgd->fifo_end - sgd->fifo_pos);
+    //pclog("fifo_end - fifo_pos = %d\n", sgd->fifo_end - sgd->fifo_pos);
     switch (dev->sgd_regs[0x02] & 0x30) {
 	case 0x00: /* Mono, 8-bit PCM */
 		if ((sgd->fifo_end - sgd->fifo_pos) >= 1)

From 7db35aa9b67663884f5dbed69662205fa428c26e Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 18 Jul 2021 16:17:56 -0300
Subject: [PATCH 13/52] De-duplicate entry field on the SGD structure

---
 src/sound/snd_ac97_via.c | 74 ++++++++++++++++++++--------------------
 1 file changed, 37 insertions(+), 37 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 382978526..fb9d1da98 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -35,10 +35,9 @@ typedef struct {
     uint8_t	id;
     struct _ac97_via_ *dev;
 
-    uint64_t	entry;
     uint32_t	entry_ptr, sample_ptr, fifo_pos, fifo_end;
     int32_t	sample_count;
-    uint8_t	fifo[32];
+    uint8_t	entry_flags, fifo[32];
 
     pc_timer_t	timer;
 } ac97_via_sgd_t;
@@ -118,11 +117,11 @@ ac97_via_update_irqs(ac97_via_t *dev, uint8_t iflag_clear)
 {
     /* Check interrupt flags on all SGDs. */
     for (uint8_t i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++) {
-    	if (dev->sgd_regs[i << 4] & (dev->sgd_regs[(i << 4) | 0x02] & 0x03)) {
-    		ac97_via_log("AC97 VIA: Setting IRQ (sgd %d iflags %02X stuck %d)\n",
+	if (dev->sgd_regs[i << 4] & (dev->sgd_regs[(i << 4) | 0x02] & 0x03)) {
+		ac97_via_log("AC97 VIA: Setting IRQ (sgd %d iflags %02X stuck %d)\n",
 			     i, dev->sgd_regs[i << 4] & (dev->sgd_regs[(i << 4) | 0x02] & 0x03), dev->irq_stuck);
 
-    		if (dev->irq_stuck && !iflag_clear) {
+		if (dev->irq_stuck && !iflag_clear) {
 #ifdef ENABLE_AC97_VIA_LOG
 			ac97_via_lost_irqs++;
 #endif
@@ -133,7 +132,7 @@ ac97_via_update_irqs(ac97_via_t *dev, uint8_t iflag_clear)
 		dev->irq_stuck = !dev->irq_stuck;
 
 		return;
-    	}
+	}
     }
 
     /* No interrupt pending. */
@@ -154,9 +153,9 @@ ac97_via_sgd_read(uint16_t addr, void *priv)
     uint8_t ret;
 
     if (!(addr & 0x80)) {
-    	/* Process SGD channel registers. */
-    	switch (addr & 0xf) {
-    		case 0x4:
+	/* Process SGD channel registers. */
+	switch (addr & 0xf) {
+		case 0x4:
 			ret = dev->sgd[addr >> 4].entry_ptr;
 			break;
 
@@ -187,9 +186,9 @@ ac97_via_sgd_read(uint16_t addr, void *priv)
 		default:
 			ret = dev->sgd_regs[addr];
 			break;
-    	}
+	}
     } else {
-    	/* Process regular registers. */
+	/* Process regular registers. */
 	switch (addr) {
 		case 0x84:
 			ret  = (dev->sgd_regs[0x00] & 0x01);
@@ -256,7 +255,7 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 	return;
 
     if (!(addr & 0x80)) {
-    	/* Process SGD channel registers. */
+	/* Process SGD channel registers. */
 	switch (addr & 0xf) {
 		case 0x0:
 			/* Clear RWC status bits. */
@@ -281,7 +280,7 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 					dev->sgd_regs[addr & 0xf0] &= ~0x44;
 
 					/* Start at the specified entry pointer. */
-					dev->sgd[addr >> 4].entry = 0;
+					dev->sgd[addr >> 4].sample_ptr = 0;
 					dev->sgd[addr >> 4].entry_ptr = (dev->sgd_regs[(addr & 0xf0) | 0x7] << 24) | (dev->sgd_regs[(addr & 0xf0) | 0x6] << 16) | (dev->sgd_regs[(addr & 0xf0) | 0x5] << 8) | (dev->sgd_regs[(addr & 0xf0) | 0x4] & 0xfe);
 
 					/* Start the actual SGD process. */
@@ -312,7 +311,7 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 			return;
 	}
     } else {
-    	/* Process regular registers. */
+	/* Process regular registers. */
 	switch (addr) {
 		case 0x30 ... 0x3f:
 		case 0x60 ... 0x7f:
@@ -482,34 +481,35 @@ ac97_via_sgd_process(void *priv)
 
     /* Process SGD if active, unless this is Audio Read and there's no room in the FIFO. */
     if (((dev->sgd_regs[sgd->id] & 0xc4) == 0x80) && (sgd->id || ((sgd->fifo_end - sgd->fifo_pos) <= (sizeof(sgd->fifo) - 4)))) {
-    	/* Move on to the next block if no entry is present. */
-	if (!sgd->entry) {
+	/* Move on to the next block if no entry is present. */
+	if (!sgd->sample_ptr) {
 		/* Start at first entry if no pointer is present. */
 		if (!sgd->entry_ptr)
 			sgd->entry_ptr = (dev->sgd_regs[sgd->id | 0x7] << 24) | (dev->sgd_regs[sgd->id | 0x6] << 16) | (dev->sgd_regs[sgd->id | 0x5] << 8) | (dev->sgd_regs[sgd->id | 0x4] & 0xfe);
 
 		/* Read entry. */
-		sgd->entry = ((uint64_t) mem_readl_phys(sgd->entry_ptr + 4) << 32ULL) | (uint64_t) mem_readl_phys(sgd->entry_ptr);
+		sgd->sample_ptr = mem_readl_phys(sgd->entry_ptr);
+		sgd->entry_ptr += 4;
+		sgd->sample_count = mem_readl_phys(sgd->entry_ptr);
+		sgd->entry_ptr += 4;
 #ifdef ENABLE_AC97_VIA_LOG
-		if (sgd->entry == 0xffffffffffffffffULL)
+		if ((sgd->sample_ptr == 0xffffffff) || (sgd->sample_ptr == 0x00000000) ||
+		    (sgd->sample_count == 0xffffffff) || (sgd->sample_count == 0x00000000))
 			fatal("AC97 VIA: Invalid SGD %d entry at %08X\n", sgd->id >> 4, sgd->entry_ptr);
 #endif
 
-		/* Set sample pointer and count. */
-		sgd->sample_ptr = sgd->entry & 0xffffffff;
-		sgd->sample_count = (sgd->entry >> 32) & 0xffffff;
+		/* Extract flags from the most significant byte. */
+		sgd->entry_flags = sgd->sample_count >> 24;
+		sgd->sample_count &= 0xffffff;
 
-		ac97_via_log("AC97 VIA: Starting SGD %d block at %08X entry %08X%08X (start %08X len %06X) lostirqs %d\n", sgd->id >> 4, sgd->entry_ptr,
-			     mem_readl_phys(sgd->entry_ptr + 4), mem_readl_phys(sgd->entry_ptr), sgd->sample_ptr, sgd->sample_count, ac97_via_lost_irqs);
-
-		/* Increment entry pointer now, as Linux expects it to be one block ahead. */
-		sgd->entry_ptr += 8;
+		ac97_via_log("AC97 VIA: Starting SGD %d block at %08X start %08X len %06X flags %02X lostirqs %d\n", sgd->id >> 4,
+			     sgd->entry_ptr, sgd->sample_ptr, sgd->sample_count, sgd->entry_flags, ac97_via_lost_irqs);
 	}
 
-        if (sgd->id & 0x10) {
-        	/* Write channel: read data from FIFO. */
-        	mem_writel_phys(sgd->sample_ptr, *((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]));
-        } else {
+	if (sgd->id & 0x10) {
+    	/* Write channel: read data from FIFO. */
+    	mem_writel_phys(sgd->sample_ptr, *((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]));
+	} else {
 		/* Read channel: write data to FIFO. */
 		*((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]) = mem_readl_phys(sgd->sample_ptr);
 	}
@@ -521,12 +521,12 @@ ac97_via_sgd_process(void *priv)
 	if (sgd->sample_count <= 0) {
 		ac97_via_log("AC97 VIA: Ending SGD %d block", sgd->id >> 4);
 
-		if (sgd->entry & 0x2000000000000000ULL) {
+		if (sgd->entry_flags & 0x20) {
 			ac97_via_log(" with STOP");
 			dev->sgd_regs[sgd->id] |= 0x04;
 		}
 
-		if (sgd->entry & 0x4000000000000000ULL) {
+		if (sgd->entry_flags & 0x40) {
 			ac97_via_log(" with FLAG");
 
 			/* Raise FLAG while also pausing SGD. */
@@ -538,7 +538,7 @@ ac97_via_sgd_process(void *priv)
 #endif
 		}
 
-		if (sgd->entry & 0x8000000000000000ULL) {
+		if (sgd->entry_flags & 0x80) {
 			ac97_via_log(" with EOL");
 
 			/* Raise EOL. */
@@ -568,7 +568,7 @@ ac97_via_sgd_process(void *priv)
 		ac97_via_log("\n");
 
 		/* Move on to a new block on the next run. */
-		sgd->entry = sgd->sample_count = 0;
+		sgd->sample_ptr = sgd->sample_count = 0;
 	}
     }
 
@@ -663,10 +663,10 @@ ac97_via_init(const device_t *info)
 
     /* Set up SGD channels. */
     for (uint8_t i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++) {
-    	dev->sgd[i].id = i << 4;
-    	dev->sgd[i].dev = dev;
+	dev->sgd[i].id = i << 4;
+	dev->sgd[i].dev = dev;
 
-    	timer_add(&dev->sgd[i].timer, ac97_via_sgd_process, &dev->sgd[i], 0);
+	timer_add(&dev->sgd[i].timer, ac97_via_sgd_process, &dev->sgd[i], 0);
     }
 
     /* Set up playback poller. */

From dffca679c0a9980b4ac6d342373ac4902e31c303 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 18 Jul 2021 19:03:01 -0300
Subject: [PATCH 14/52] Make CS423x Sound Blaster Pro a generic compatibility
 device in preparation for VT82C686

---
 src/include/86box/sound.h |  2 +-
 src/sound/snd_cs423x.c    |  2 +-
 src/sound/snd_sb.c        | 10 +++++-----
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/include/86box/sound.h b/src/include/86box/sound.h
index b15724cdd..1ca29ea18 100644
--- a/src/include/86box/sound.h
+++ b/src/include/86box/sound.h
@@ -110,7 +110,7 @@ extern const device_t sb_2_device;
 extern const device_t sb_pro_v1_device;
 extern const device_t sb_pro_v2_device;
 extern const device_t sb_pro_mcv_device;
-extern const device_t sb_pro_cs423x_device;
+extern const device_t sb_pro_compat_device;
 extern const device_t sb_16_device;
 extern const device_t sb_16_pnp_device;
 extern const device_t sb_32_pnp_device;
diff --git a/src/sound/snd_cs423x.c b/src/sound/snd_cs423x.c
index 03a258f30..17b386360 100644
--- a/src/sound/snd_cs423x.c
+++ b/src/sound/snd_cs423x.c
@@ -788,7 +788,7 @@ cs423x_init(const device_t *info)
 
     /* Initialize SBPro codec first to get the correct CD audio filter for the default
        context, which is SBPro. The WSS codec is initialized later by cs423x_reset */
-    dev->sb = (sb_t *) device_add(&sb_pro_cs423x_device);
+    dev->sb = device_add(&sb_pro_compat_device);
 
     /* Initialize RAM, registers and WSS codec. */
     cs423x_reset(dev);
diff --git a/src/sound/snd_sb.c b/src/sound/snd_sb.c
index 8e1ea61a4..9e458c740 100644
--- a/src/sound/snd_sb.c
+++ b/src/sound/snd_sb.c
@@ -1625,12 +1625,12 @@ sb_pro_mcv_init(const device_t *info)
 
 
 static void *
-sb_pro_cs423x_init(const device_t *info)
+sb_pro_compat_init(const device_t *info)
 {
     sb_t *sb = malloc(sizeof(sb_t));
     memset(sb, 0, sizeof(sb_t));
 
-    sb->opl_enabled = 0; /* updated by cs423x code */
+    sb->opl_enabled = 0; /* CS423x updates this, while VT82C686 lacks OPL */
     opl3_init(&sb->opl);
 
     sb_dsp_init(&sb->dsp, SBPRO2, SB_SUBTYPE_DEFAULT, sb);
@@ -2534,12 +2534,12 @@ const device_t sb_pro_mcv_device =
         NULL
 };
 
-const device_t sb_pro_cs423x_device =
+const device_t sb_pro_compat_device =
 {
-        "Crystal CS423x Sound Blaster Pro compatibility",
+        "Sound Blaster Pro (Compatibility)",
         DEVICE_ISA | DEVICE_AT,
 	0,
-        sb_pro_cs423x_init, sb_close, NULL, { NULL },
+        sb_pro_compat_init, sb_close, NULL, { NULL },
         sb_speed_changed,
         NULL,
         NULL

From ce63373613c7aab15e690ad3d5ab3443ef419e3b Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Thu, 22 Jul 2021 11:10:05 -0300
Subject: [PATCH 15/52] Add incomplete VIA AC97 FM implementation

---
 src/chipset/via_pipc.c   | 146 ++++++++++++++++++++++++++++++++++-----
 src/sound/snd_ac97_via.c |  59 ++++++++++++----
 2 files changed, 175 insertions(+), 30 deletions(-)

diff --git a/src/chipset/via_pipc.c b/src/chipset/via_pipc.c
index d0fbdfa63..b984aa07a 100644
--- a/src/chipset/via_pipc.c
+++ b/src/chipset/via_pipc.c
@@ -50,7 +50,10 @@
 #include <86box/sio.h>
 #include <86box/hwm.h>
 #include <86box/gameport.h>
+#include <86box/sound.h>
 #include <86box/snd_ac97.h>
+#include <86box/snd_sb.h>
+#include <86box/nmi.h>
 
 /* Most revision numbers (PCI-ISA bridge or otherwise) were lifted from PCI device
    listings on forums, as VIA's datasheets are not very helpful regarding those. */
@@ -68,11 +71,11 @@ typedef struct
     uint32_t	local;
     uint8_t	max_func;
 
-    uint8_t	pci_isa_regs[256];
-    uint8_t	ide_regs[256];
-    uint8_t	usb_regs[2][256];
-    uint8_t	power_regs[256];
-    uint8_t	ac97_regs[2][256];
+    uint8_t	pci_isa_regs[256],
+		ide_regs[256],
+		usb_regs[2][256],
+		power_regs[256],
+		ac97_regs[2][256], fmnmi_regs[4], fm_regs[4];
     sff8038i_t	*bm[2];
     nvr_t	*nvr;
     int		nvr_enabled, slot;
@@ -80,7 +83,9 @@ typedef struct
     usb_t	*usb[2];
     acpi_t	*acpi;
     void	*gameport, *ac97;
-    uint16_t	midigame_base;
+    sb_t	*sb;
+    uint16_t	midigame_base, fmnmi_base;
+    uint8_t	fm_enabled;
 } pipc_t;
 
 
@@ -355,6 +360,7 @@ pipc_reset_hard(void *priv)
 			dev->ac97_regs[i][0x40] = 0x01;
 
 		dev->ac97_regs[i][0x43] = 0x1c;
+		dev->ac97_regs[i][0x48] = 0x01;
 		dev->ac97_regs[i][0x4b] = 0x02;
 
 		pipc_sgd_handlers(dev, i);
@@ -456,12 +462,12 @@ static void
 pipc_sgd_handlers(pipc_t *dev, uint8_t modem)
 {
     if (!dev->ac97)
-    	return;
+	return;
 
     if (modem)
-    	ac97_via_remap_modem_sgd(dev->ac97, dev->ac97_regs[1][0x11] << 8, dev->ac97_regs[1][0x04] & PCI_COMMAND_IO);
+	ac97_via_remap_modem_sgd(dev->ac97, dev->ac97_regs[1][0x11] << 8, dev->ac97_regs[1][0x04] & PCI_COMMAND_IO);
     else
-    	ac97_via_remap_audio_sgd(dev->ac97, dev->ac97_regs[0][0x11] << 8, dev->ac97_regs[0][0x04] & PCI_COMMAND_IO);
+	ac97_via_remap_audio_sgd(dev->ac97, dev->ac97_regs[0][0x11] << 8, dev->ac97_regs[0][0x04] & PCI_COMMAND_IO);
 }
 
 
@@ -516,12 +522,94 @@ static void
 pipc_codec_handlers(pipc_t *dev, uint8_t modem)
 {
     if (!dev->ac97)
-    	return;
+	return;
 
     if (modem)
-    	ac97_via_remap_modem_codec(dev->ac97, dev->ac97_regs[1][0x1d] << 8, dev->ac97_regs[1][0x04] & PCI_COMMAND_IO);
+	ac97_via_remap_modem_codec(dev->ac97, dev->ac97_regs[1][0x1d] << 8, dev->ac97_regs[1][0x04] & PCI_COMMAND_IO);
     else
-    	ac97_via_remap_audio_codec(dev->ac97, dev->ac97_regs[0][0x1d] << 8, dev->ac97_regs[0][0x04] & PCI_COMMAND_IO);
+	ac97_via_remap_audio_codec(dev->ac97, dev->ac97_regs[0][0x1d] << 8, dev->ac97_regs[0][0x04] & PCI_COMMAND_IO);
+}
+
+
+static uint8_t
+pipc_fmnmi_read(uint16_t addr, void *priv)
+{
+    pipc_t *dev = (pipc_t *) priv;
+    uint8_t ret = dev->fmnmi_regs[addr & 0x03];
+
+    pipc_log("PIPC: fmnmi_read(%02X) = %02X\n", addr & 0x03, ret);
+
+    if (dev->ac97_regs[0][0x48] & 0x04)
+	smi_line = 0;
+    else
+	nmi = 0;
+
+    return ret;
+}
+
+
+static void
+pipc_fmnmi_write(uint16_t addr, uint8_t val, void *priv)
+{
+    pipc_t *dev = (pipc_t *) priv;
+
+    pipc_log("PIPC: fmnmi_write(%02X, %02X)\n", addr & 0x03, val);
+}
+
+
+static uint8_t
+pipc_fm_read(uint16_t addr, void *priv)
+{
+    pipc_t *dev = (pipc_t *) priv;
+    uint8_t ret = opl3_read(addr, &dev->sb->opl);
+
+    pipc_log("PIPC: fm_read(%02X) = %02X\n", addr & 0x03, ret);
+
+    return ret;
+}
+
+
+static void
+pipc_fm_write(uint16_t addr, uint8_t val, void *priv)
+{
+    pipc_t *dev = (pipc_t *) priv;
+
+    pipc_log("PIPC: fm_write(%02X, %02X)\n", addr & 0x03, val);
+
+    opl3_write(addr, val, &dev->sb->opl);
+    dev->fm_regs[addr & 0x03] = val;
+
+    dev->fmnmi_regs[0x00] = (addr & 0x02) ? 0x02 : 0x01;
+    dev->fmnmi_regs[0x01] = dev->fm_regs[addr & 0x02];
+    dev->fmnmi_regs[0x02] = dev->fm_regs[(addr & 0x02) | 0x01];
+
+    if (dev->ac97_regs[0][0x48] & 0x04)
+	smi_line = 1;
+    else
+	nmi = 1;
+}
+
+
+static void
+pipc_fmnmi_handlers(pipc_t *dev, uint8_t modem)
+{
+    if (!dev->ac97 || modem)
+	return;
+
+    if (dev->fmnmi_base)
+	io_removehandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, pipc_fmnmi_write, NULL, NULL, dev);
+
+    if (dev->fm_enabled)
+	io_removehandler(0x388, 4, pipc_fm_read, NULL, NULL, pipc_fm_write, NULL, NULL, dev);
+
+    dev->fmnmi_base = (dev->ac97_regs[0][0x15] << 8) | (dev->ac97_regs[0][0x14] & 0xfc);
+    dev->fm_enabled = !!(dev->ac97_regs[0][0x42] & 0x04);
+
+    if (dev->fmnmi_base && (dev->ac97_regs[0][0x04] & PCI_COMMAND_IO))
+	io_sethandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, pipc_fmnmi_write, NULL, NULL, dev);
+
+    if (dev->fm_enabled)
+	io_sethandler(0x388, 4, pipc_fm_read, NULL, NULL, pipc_fm_write, NULL, NULL, dev);
 }
 
 
@@ -1096,6 +1184,7 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			pipc_midigame_handlers(dev, func);
 			pipc_sgd_handlers(dev, func);
 			pipc_codec_handlers(dev, func);
+			pipc_fmnmi_handlers(dev, func);
 			break;
 
 		case 0x09: case 0x0a: case 0x0b:
@@ -1103,11 +1192,18 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 				dev->ac97_regs[func][addr] = val;
 			break;
 
-		case 0x11:
+		case 0x10: case 0x11:
 			dev->ac97_regs[func][addr] = val;
 			pipc_sgd_handlers(dev, func);
 			break;
 
+		case 0x14: case 0x15:
+			if (addr == 0x14)
+				val = (val & 0xfc) | 1;
+			dev->ac97_regs[func][addr] = val;
+			pipc_fmnmi_handlers(dev, func);
+			break;
+
 		case 0x18: case 0x19:
 			if (addr == 0x18)
 				val = (val & 0xfc) | 1;
@@ -1115,7 +1211,7 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			pipc_midigame_handlers(dev, func);
 			break;
 
-		case 0x1c:
+		case 0x1c: case 0x1d:
 			dev->ac97_regs[func][addr] = val;
 			pipc_codec_handlers(dev, func);
 			break;
@@ -1128,10 +1224,8 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 		case 0x42: case 0x4a: case 0x4b:
 			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val;
 			gameport_remap(dev->gameport, (dev->ac97_regs[0][0x42] & 0x08) ? ((dev->ac97_regs[0][0x4b] << 8) | dev->ac97_regs[0][0x4a]) : 0);
-			break;
-
-		case 0x41:
-			dev->ac97_regs[func][addr] = val;
+			if (addr == 0x42)
+				pipc_fmnmi_handlers(dev, func);
 			break;
 
 		case 0x43:
@@ -1146,6 +1240,20 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val & 0x0f;
 			break;
 
+		case 0x48:
+			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val & 0x0f;
+			/*if (!(val & 0x01)) {
+				if (val & 0x04)
+					smi_line = 0;
+				else
+					nmi = 0;
+			}*/
+			if (val & 0x04)
+				smi_line = !!(val & 0x01);
+			else
+				nmi = !!(val & 0x01);
+			break;
+
 		default:
 			dev->ac97_regs[func][addr] = val;
 			break;
@@ -1227,6 +1335,8 @@ pipc_init(const device_t *info)
 	dev->ac97 = device_add(&ac97_via_device);
 	ac97_via_set_slot(dev->ac97, dev->slot, PCI_INTC);
 
+	dev->sb = device_add(&sb_pro_compat_device);
+
 	dev->gameport = gameport_add(&gameport_sio_device);
     }
 
diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index fb9d1da98..b29bc01d3 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -50,15 +50,15 @@ typedef struct _ac97_via_ {
     ac97_codec_t *codec[2][2];
     ac97_via_sgd_t sgd[6];
 
-    pc_timer_t	timer_count;
+    pc_timer_t	timer_count, timer_count_fm;
     uint64_t	timer_latch, timer_fifo_latch;
-    int16_t	out_l, out_r;
+    int16_t	out_l, out_r, fm_out_l, fm_out_r;
     double	cd_vol_l, cd_vol_r;
-    int16_t	buffer[SOUNDBUFLEN * 2];
-    int		pos;
+    int16_t	buffer[SOUNDBUFLEN * 2], fm_buffer[SOUNDBUFLEN * 2];
+    int		pos, fm_pos;
 } ac97_via_t;
 
-//#define ENABLE_AC97_VIA_LOG 1
+#define ENABLE_AC97_VIA_LOG 1
 #ifdef ENABLE_AC97_VIA_LOG
 int ac97_via_do_log = ENABLE_AC97_VIA_LOG;
 unsigned int ac97_via_lost_irqs = 0;
@@ -111,7 +111,7 @@ ac97_via_read_status(void *priv, uint8_t modem)
     return ret;
 }
 
-
+#include <86box/nmi.h>
 static void
 ac97_via_update_irqs(ac97_via_t *dev, uint8_t iflag_clear)
 {
@@ -473,6 +473,16 @@ ac97_via_update(ac97_via_t *dev)
 }
 
 
+static void
+ac97_via_update_fm(ac97_via_t *dev)
+{
+    for (; dev->fm_pos < sound_pos_global; dev->fm_pos++) {
+	dev->fm_buffer[dev->fm_pos*2]     = dev->fm_out_l;
+	dev->fm_buffer[dev->fm_pos*2 + 1] = dev->fm_out_r;
+    }
+}
+
+
 static void
 ac97_via_sgd_process(void *priv)
 {
@@ -503,12 +513,12 @@ ac97_via_sgd_process(void *priv)
 		sgd->sample_count &= 0xffffff;
 
 		ac97_via_log("AC97 VIA: Starting SGD %d block at %08X start %08X len %06X flags %02X lostirqs %d\n", sgd->id >> 4,
-			     sgd->entry_ptr, sgd->sample_ptr, sgd->sample_count, sgd->entry_flags, ac97_via_lost_irqs);
+			     sgd->entry_ptr - 8, sgd->sample_ptr, sgd->sample_count, sgd->entry_flags, ac97_via_lost_irqs);
 	}
 
 	if (sgd->id & 0x10) {
-    	/* Write channel: read data from FIFO. */
-    	mem_writel_phys(sgd->sample_ptr, *((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]));
+	/* Write channel: read data from FIFO. */
+	mem_writel_phys(sgd->sample_ptr, *((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]));
 	} else {
 		/* Read channel: write data to FIFO. */
 		*((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]) = mem_readl_phys(sgd->sample_ptr);
@@ -625,17 +635,40 @@ ac97_via_poll(void *priv)
 }
 
 
+static void
+ac97_via_poll_fm(void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    ac97_via_sgd_t *sgd = &dev->sgd[2]; /* FM Read */
+
+    timer_advance_u64(&dev->timer_count_fm, dev->timer_latch);
+
+    ac97_via_update_fm(dev);
+
+    dev->fm_out_l = dev->fm_out_r = 0;
+
+    /* Unknown format, assumed. */
+    if ((sgd->fifo_end - sgd->fifo_pos) >= 2) {
+	dev->out_l = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+	dev->out_r = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+    }
+}
+
+
 static void
 ac97_via_get_buffer(int32_t *buffer, int len, void *priv)
 {
     ac97_via_t *dev = (ac97_via_t *) priv;
 
     ac97_via_update(dev);
+    ac97_via_update_fm(dev);
 
-    for (int c = 0; c < len * 2; c++)
+    for (int c = 0; c < len * 2; c++) {
 	buffer[c] += dev->buffer[c];
+	buffer[c] += dev->fm_buffer[c];
+    }
 
-    dev->pos = 0;
+    dev->pos = dev->fm_pos = 0;
 }
 
 
@@ -669,10 +702,12 @@ ac97_via_init(const device_t *info)
 	timer_add(&dev->sgd[i].timer, ac97_via_sgd_process, &dev->sgd[i], 0);
     }
 
-    /* Set up playback poller. */
+    /* Set up playback pollers. */
     timer_add(&dev->timer_count, ac97_via_poll, dev, 0);
+    timer_add(&dev->timer_count_fm, ac97_via_poll_fm, dev, 0);
     ac97_via_speed_changed(dev);
     timer_advance_u64(&dev->timer_count, dev->timer_latch);
+    timer_advance_u64(&dev->timer_count_fm, dev->timer_latch);
 
     /* Set up playback handler. */
     sound_add_handler(ac97_via_get_buffer, dev);

From c2e9ba1db57a13eace63ffa101b6ce551df5e87d Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Thu, 22 Jul 2021 16:06:45 -0300
Subject: [PATCH 16/52] Add CS4297 codec to onboard ES1371 implementations

---
 src/include/86box/snd_ac97.h |  1 +
 src/machine/m_at_slot1.c     | 12 ++++++++----
 src/sound/snd_ac97_codec.c   | 13 +++++++++++++
 src/sound/snd_audiopci.c     |  3 ++-
 4 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/include/86box/snd_ac97.h b/src/include/86box/snd_ac97.h
index 9c4bd308a..da2bb8b95 100644
--- a/src/include/86box/snd_ac97.h
+++ b/src/include/86box/snd_ac97.h
@@ -41,6 +41,7 @@ extern ac97_codec_t	**ac97_codec, **ac97_modem_codec;
 extern int		ac97_codec_count, ac97_modem_codec_count;
 
 extern const device_t	alc100_device;
+extern const device_t	cs4297_device;
 extern const device_t	cs4297a_device;
 extern const device_t	wm9701a_device;
 
diff --git a/src/machine/m_at_slot1.c b/src/machine/m_at_slot1.c
index a14d75cd7..535e8ad74 100644
--- a/src/machine/m_at_slot1.c
+++ b/src/machine/m_at_slot1.c
@@ -468,8 +468,10 @@ machine_at_tsunamiatx_init(const machine_t *model)
     device_add(&i440bx_device);
     device_add(&piix4e_device);
 
-    if (sound_card_current == SOUND_INTERNAL)
-    	device_add(&es1371_onboard_device);
+    if (sound_card_current == SOUND_INTERNAL) {
+	device_add(&es1371_onboard_device);
+	device_add(&cs4297_device); /* found on other Tyan boards around the same time */
+    }
 
     device_add(&pc87309_device);
     device_add(&keyboard_ps2_ami_pci_device);
@@ -678,8 +680,10 @@ machine_at_ms6168_common_init(const machine_t *model)
     if (gfxcard == VID_INTERNAL)
     	device_add(&voodoo_3_2000_agp_onboard_8m_device);
 
-    if (sound_card_current == SOUND_INTERNAL)
-    	device_add(&es1371_onboard_device);
+    if (sound_card_current == SOUND_INTERNAL) {
+	device_add(&es1371_onboard_device);
+	device_add(&cs4297_device);
+    }
 }
 
 
diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index 57083d590..a4b3c7e1c 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -30,6 +30,7 @@
 
 enum {
     AC97_CODEC_ALC100 = AC97_CODEC_ID('A', 'L', 'C', 0x20),
+    AC97_CODEC_CS4297 = AC97_CODEC_ID('C', 'R', 'Y', 0x03),
     AC97_CODEC_CS4297A = AC97_CODEC_ID('C', 'R', 'Y', 0x11),
     AC97_CODEC_WM9701A = AC97_CODEC_ID('W', 'M', 'L', 0x00)
 };
@@ -228,6 +229,18 @@ const device_t alc100_device =
     NULL
 };
 
+const device_t cs4297_device =
+{
+    "Crystal CS4297",
+    DEVICE_AC97,
+    AC97_CODEC_CS4297,
+    ac97_codec_init, ac97_codec_close, ac97_codec_reset,
+    { NULL },
+    NULL,
+    NULL,
+    NULL
+};
+
 const device_t cs4297a_device =
 {
     "Crystal CS4297A",
diff --git a/src/sound/snd_audiopci.c b/src/sound/snd_audiopci.c
index ee529c59f..a41b9afff 100644
--- a/src/sound/snd_audiopci.c
+++ b/src/sound/snd_audiopci.c
@@ -1366,7 +1366,8 @@ static void *es1371_init(const device_t *info)
 
 	ac97_codec = &es1371->codec;
 	ac97_codec_count = 1;
-	device_add(&cs4297a_device);
+	if (!info->local)
+		device_add(&cs4297a_device);
 
 	return es1371;
 }

From 1fc1171011ea8f593f2f3a2663d97d1a3fa61a74 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Thu, 22 Jul 2021 16:07:38 -0300
Subject: [PATCH 17/52] Return the same CS4297A revision VMware does

---
 src/sound/snd_ac97_codec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index a4b3c7e1c..6a6d45f87 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -31,7 +31,7 @@
 enum {
     AC97_CODEC_ALC100 = AC97_CODEC_ID('A', 'L', 'C', 0x20),
     AC97_CODEC_CS4297 = AC97_CODEC_ID('C', 'R', 'Y', 0x03),
-    AC97_CODEC_CS4297A = AC97_CODEC_ID('C', 'R', 'Y', 0x11),
+    AC97_CODEC_CS4297A = AC97_CODEC_ID('C', 'R', 'Y', 0x13),
     AC97_CODEC_WM9701A = AC97_CODEC_ID('W', 'M', 'L', 0x00)
 };
 

From 42b4073b10a288331332a044b05400741c815360 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Thu, 22 Jul 2021 23:47:32 -0300
Subject: [PATCH 18/52] Fix build

---
 src/machine/m_at_slot1.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/machine/m_at_slot1.c b/src/machine/m_at_slot1.c
index 535e8ad74..c69226ebc 100644
--- a/src/machine/m_at_slot1.c
+++ b/src/machine/m_at_slot1.c
@@ -38,6 +38,7 @@
 #include <86box/machine.h>
 #include <86box/sound.h>
 #include <86box/clock.h>
+#include <86box/snd_ac97.h>
 
 int
 machine_at_p65up5_cpknd_init(const machine_t *model)

From 562bbe167c50fa4a3c6ea55226b6f5e5732d2ef1 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Fri, 23 Jul 2021 01:07:53 -0300
Subject: [PATCH 19/52] Improvements to VIA AC97 per suggestions

---
 src/sound/snd_ac97_via.c | 38 ++++++++++++--------------------------
 1 file changed, 12 insertions(+), 26 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index b29bc01d3..eb12234e5 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -111,34 +111,20 @@ ac97_via_read_status(void *priv, uint8_t modem)
     return ret;
 }
 
-#include <86box/nmi.h>
+
 static void
 ac97_via_update_irqs(ac97_via_t *dev, uint8_t iflag_clear)
 {
+    uint8_t do_irq = 0;
+
     /* Check interrupt flags on all SGDs. */
-    for (uint8_t i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++) {
-	if (dev->sgd_regs[i << 4] & (dev->sgd_regs[(i << 4) | 0x02] & 0x03)) {
-		ac97_via_log("AC97 VIA: Setting IRQ (sgd %d iflags %02X stuck %d)\n",
-			     i, dev->sgd_regs[i << 4] & (dev->sgd_regs[(i << 4) | 0x02] & 0x03), dev->irq_stuck);
+    for (uint8_t i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++)
+	do_irq |= (dev->sgd_regs[i << 4] & (dev->sgd_regs[(i << 4) | 0x02] & 0x03));
 
-		if (dev->irq_stuck && !iflag_clear) {
-#ifdef ENABLE_AC97_VIA_LOG
-			ac97_via_lost_irqs++;
-#endif
-			pci_clear_irq(dev->slot, dev->irq_pin);
-		} else {
-			pci_set_irq(dev->slot, dev->irq_pin);
-		}
-		dev->irq_stuck = !dev->irq_stuck;
-
-		return;
-	}
-    }
-
-    /* No interrupt pending. */
-    //ac97_via_log("AC97 VIA: Clearing IRQ\n");
-    pci_clear_irq(dev->slot, dev->irq_pin);
-    dev->irq_stuck = 0;
+    if (do_irq)
+	pci_set_irq(dev->slot, dev->irq_pin);
+    else
+	pci_clear_irq(dev->slot, dev->irq_pin);
 }
 
 
@@ -495,7 +481,7 @@ ac97_via_sgd_process(void *priv)
 	if (!sgd->sample_ptr) {
 		/* Start at first entry if no pointer is present. */
 		if (!sgd->entry_ptr)
-			sgd->entry_ptr = (dev->sgd_regs[sgd->id | 0x7] << 24) | (dev->sgd_regs[sgd->id | 0x6] << 16) | (dev->sgd_regs[sgd->id | 0x5] << 8) | (dev->sgd_regs[sgd->id | 0x4] & 0xfe);
+			sgd->entry_ptr = *((uint32_t *) &dev->sgd_regs[sgd->id | 0x4]) & 0xfffffffe;
 
 		/* Read entry. */
 		sgd->sample_ptr = mem_readl_phys(sgd->entry_ptr);
@@ -517,8 +503,8 @@ ac97_via_sgd_process(void *priv)
 	}
 
 	if (sgd->id & 0x10) {
-	/* Write channel: read data from FIFO. */
-	mem_writel_phys(sgd->sample_ptr, *((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]));
+		/* Write channel: read data from FIFO. */
+		mem_writel_phys(sgd->sample_ptr, *((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]));
 	} else {
 		/* Read channel: write data to FIFO. */
 		*((uint32_t *) &sgd->fifo[sgd->fifo_end & (sizeof(sgd->fifo) - 1)]) = mem_readl_phys(sgd->sample_ptr);

From 293c4a02810b9fddf80284054e19007756d03640 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sat, 24 Jul 2021 22:37:05 -0300
Subject: [PATCH 20/52] Fix unused variable warning

---
 src/chipset/via_pipc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/chipset/via_pipc.c b/src/chipset/via_pipc.c
index b984aa07a..7c8757b81 100644
--- a/src/chipset/via_pipc.c
+++ b/src/chipset/via_pipc.c
@@ -551,7 +551,9 @@ pipc_fmnmi_read(uint16_t addr, void *priv)
 static void
 pipc_fmnmi_write(uint16_t addr, uint8_t val, void *priv)
 {
+#ifdef ENABLE_PIPC_LOG
     pipc_t *dev = (pipc_t *) priv;
+#endif
 
     pipc_log("PIPC: fmnmi_write(%02X, %02X)\n", addr & 0x03, val);
 }

From 0fe3a712b00a1979381af5626a88cc97bdc2123a Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sat, 24 Jul 2021 22:38:05 -0300
Subject: [PATCH 21/52] Move SGD restart to a dedicated flag variable

---
 src/sound/snd_ac97_via.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index eb12234e5..8ddc590a4 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -37,7 +37,7 @@ typedef struct {
 
     uint32_t	entry_ptr, sample_ptr, fifo_pos, fifo_end;
     int32_t	sample_count;
-    uint8_t	entry_flags, fifo[32];
+    uint8_t	entry_flags, fifo[32], restart;
 
     pc_timer_t	timer;
 } ac97_via_sgd_t;
@@ -267,7 +267,8 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 
 					/* Start at the specified entry pointer. */
 					dev->sgd[addr >> 4].sample_ptr = 0;
-					dev->sgd[addr >> 4].entry_ptr = (dev->sgd_regs[(addr & 0xf0) | 0x7] << 24) | (dev->sgd_regs[(addr & 0xf0) | 0x6] << 16) | (dev->sgd_regs[(addr & 0xf0) | 0x5] << 8) | (dev->sgd_regs[(addr & 0xf0) | 0x4] & 0xfe);
+					dev->sgd[addr >> 4].entry_ptr = *((uint32_t *) &dev->sgd_regs[(addr & 0xf0) | 0x4]) & 0xfffffffe;
+					dev->sgd[addr >> 4].restart = 1;
 
 					/* Start the actual SGD process. */
 					timer_advance_u64(&dev->sgd[addr >> 4].timer, 0);
@@ -478,7 +479,9 @@ ac97_via_sgd_process(void *priv)
     /* Process SGD if active, unless this is Audio Read and there's no room in the FIFO. */
     if (((dev->sgd_regs[sgd->id] & 0xc4) == 0x80) && (sgd->id || ((sgd->fifo_end - sgd->fifo_pos) <= (sizeof(sgd->fifo) - 4)))) {
 	/* Move on to the next block if no entry is present. */
-	if (!sgd->sample_ptr) {
+    	if (sgd->restart) {
+    		sgd->restart = 0;
+
 		/* Start at first entry if no pointer is present. */
 		if (!sgd->entry_ptr)
 			sgd->entry_ptr = *((uint32_t *) &dev->sgd_regs[sgd->id | 0x4]) & 0xfffffffe;
@@ -489,9 +492,10 @@ ac97_via_sgd_process(void *priv)
 		sgd->sample_count = mem_readl_phys(sgd->entry_ptr);
 		sgd->entry_ptr += 4;
 #ifdef ENABLE_AC97_VIA_LOG
-		if ((sgd->sample_ptr == 0xffffffff) || (sgd->sample_ptr == 0x00000000) ||
-		    (sgd->sample_count == 0xffffffff) || (sgd->sample_count == 0x00000000))
-			fatal("AC97 VIA: Invalid SGD %d entry at %08X\n", sgd->id >> 4, sgd->entry_ptr);
+		if (((sgd->sample_ptr == 0xffffffff) && (sgd->sample_count == 0xffffffff)) ||
+		    ((sgd->sample_ptr == 0x00000000) && (sgd->sample_count == 0x00000000)))
+			fatal("AC97 VIA: Invalid SGD %d entry %08X%08X at %08X\n", sgd->id >> 4,
+			      sgd->sample_ptr, sgd->sample_count, sgd->entry_ptr - 8);
 #endif
 
 		/* Extract flags from the most significant byte. */
@@ -553,6 +557,7 @@ ac97_via_sgd_process(void *priv)
 				dev->sgd_regs[sgd->id] &= ~0x08;
 
 				/* Go back to the starting block. */
+				//sgd->entry_ptr = *((uint32_t *) &dev->sgd_regs[sgd->id | 0x4]) & 0xfffffffe; /* why does XP not like this? */
 				sgd->entry_ptr = 0;
 			} else {
 				ac97_via_log(" finish");
@@ -564,7 +569,7 @@ ac97_via_sgd_process(void *priv)
 		ac97_via_log("\n");
 
 		/* Move on to a new block on the next run. */
-		sgd->sample_ptr = sgd->sample_count = 0;
+		sgd->restart = 1;
 	}
     }
 
@@ -588,7 +593,6 @@ ac97_via_poll(void *priv)
 
     dev->out_l = dev->out_r = 0;
 
-    //pclog("fifo_end - fifo_pos = %d\n", sgd->fifo_end - sgd->fifo_pos);
     switch (dev->sgd_regs[0x02] & 0x30) {
 	case 0x00: /* Mono, 8-bit PCM */
 		if ((sgd->fifo_end - sgd->fifo_pos) >= 1)

From 07c61a62a3b491869a9333d3365ff59851a378b7 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 25 Jul 2021 19:18:46 -0300
Subject: [PATCH 22/52] ES1371: query volumes on every codec write (for codec
 resets)

---
 src/sound/snd_audiopci.c | 45 +++++++++++++++++++---------------------
 1 file changed, 21 insertions(+), 24 deletions(-)

diff --git a/src/sound/snd_audiopci.c b/src/sound/snd_audiopci.c
index a41b9afff..d64066ccc 100644
--- a/src/sound/snd_audiopci.c
+++ b/src/sound/snd_audiopci.c
@@ -602,31 +602,28 @@ static void es1371_outl(uint16_t port, uint32_t val, void *p)
 			ac97_codec_write(es1371->codec, (val >> 16) & 0x7f, val & 0xff);
 			ac97_codec_write(es1371->codec, ((val >> 16) & 0x7f) + 1, val >> 8);
 
-			switch ((val >> 16) & 0x7f) {
-				case 0x02: /* Master Volume */
-					if (val & 0x8000) {
-						es1371->master_vol_l = es1371->master_vol_r = 0;
-					} else {
-						if (val & 0x2000)
-							es1371->master_vol_l = codec_attn[0];
-						else
-							es1371->master_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
-						if (val & 0x20)
-							es1371->master_vol_r = codec_attn[0];
-						else
-							es1371->master_vol_r = codec_attn[0x1f - (val & 0x1f)];
-					}
-					break;
-
-				case 0x12: /* CD Volume */
-					if (val & 0x8000) {
-						es1371->cd_vol_l = es1371->cd_vol_r = 0;
-					} else {
-						es1371->cd_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
-						es1371->cd_vol_r = codec_attn[0x1f - (val & 0x1f)];
-					}
-					break;
+			val = *((uint16_t *) &es1371->codec->regs[0x02]); /* Master Volume */
+			if (val & 0x8000) {
+				es1371->master_vol_l = es1371->master_vol_r = 0;
+			} else {
+				if (val & 0x2000)
+					es1371->master_vol_l = codec_attn[0];
+				else
+					es1371->master_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
+				if (val & 0x20)
+					es1371->master_vol_r = codec_attn[0];
+				else
+					es1371->master_vol_r = codec_attn[0x1f - (val & 0x1f)];
 			}
+
+			val = *((uint16_t *) &es1371->codec->regs[0x12]); /* CD Volume */
+			if (val & 0x8000) {
+				es1371->cd_vol_l = es1371->cd_vol_r = 0;
+			} else {
+				es1371->cd_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
+				es1371->cd_vol_r = codec_attn[0x1f - (val & 0x1f)];
+			}
+			break;
 		}
 		break;
 		

From b24d5219a6ed8d5a82aa7b7294caf8147b34fcb7 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 25 Jul 2021 22:43:04 -0300
Subject: [PATCH 23/52] Change some entries in the legacy CPU table conversion
 code to match renamed machines

---
 src/cpu/cpu_table.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/src/cpu/cpu_table.c b/src/cpu/cpu_table.c
index fca0d60e3..b980c5cf0 100644
--- a/src/cpu/cpu_table.c
+++ b/src/cpu/cpu_table.c
@@ -1736,7 +1736,7 @@ const cpu_legacy_machine_t cpu_legacy_table[] = {
     {"dtk",                     cputables_8088},
     {"genxt",                   cputables_8088},
     {"jukopc",                  cputables_8088},
-    {"open_xt",                 cputables_8088},
+    {"openxt",                  cputables_8088},
     {"pxxt",                    cputables_8088},
     {"europc",                  cputables_europc},
     {"tandy",                   cputables_europc},
@@ -1793,7 +1793,7 @@ const cpu_legacy_machine_t cpu_legacy_table[] = {
     {"shuttle386sx",            cputables_i386SX_Am386SX_486SLC},
     {"dtk386",                  cputables_i386SX_Am386SX_486SLC},
     {"awardsx",                 cputables_i386SX_Am386SX_486SLC},
-    {"cbm_sl386sx25",           cputables_i386SX_Am386SX_486SLC},
+    {"cmdsl386sx25",            cputables_i386SX_Am386SX_486SLC},
     {"kmxc02",                  cputables_i386SX_Am386SX_486SLC},
     {"megapc",                  cputables_i386SX_Am386SX_486SLC},
     {"ibmps2_m55sx",            cputables_i386SX_Am386SX_486SLC_IBM486SLC},
@@ -1804,8 +1804,6 @@ const cpu_legacy_machine_t cpu_legacy_table[] = {
     {"asus386",                 cputables_i386DX_Am386DX_486DLC},
     {"ustechnologies386",       cputables_i386DX_Am386DX_486DLC},
     {"award386dx",              cputables_i386DX_Am386DX_486DLC},
-    {"ami386dx",                cputables_i386DX_Am386DX_486DLC},
-    {"mr386dx",                 cputables_i386DX_Am386DX_486DLC},
     {"ibmps2_m70_type3",        cputables_i386DX_Am386DX_486DLC_IBM486BL},
     {"ibmps2_m80",              cputables_i386DX_Am386DX_486DLC_IBM486BL},
     {"pb410a",                  cputables_i486_Am486_Cx486},
@@ -1923,7 +1921,6 @@ const cpu_legacy_machine_t cpu_legacy_table[] = {
     {"tsunamiatx",              cputables_PentiumII_Celeron_Cyrix3},
     {"p6sba",                   cputables_PentiumII_Celeron_Cyrix3},
     {"ergox365",                cputables_PentiumII_Celeron_Cyrix3},
-    {"fw6400gx_s1",             cputables_PentiumII_Celeron_Cyrix3},
     {"ficka6130",               cputables_PentiumII_Celeron_Cyrix3},
     {"6gxu",                    cputables_Xeon},
     {"fw6400gx",                cputables_Xeon},
@@ -1937,7 +1934,7 @@ const cpu_legacy_machine_t cpu_legacy_table[] = {
     {"63a",                     cputables_Celeron_Cyrix3},
     {"apas3",                   cputables_Celeron_Cyrix3},
     {"wcf681",                  cputables_Celeron_Cyrix3},
-    {"6via85x",                 cputables_Celeron_Cyrix3},
+    {"6via90ap",                cputables_Celeron_Cyrix3},
     {"p6bap",                   cputables_Celeron_Cyrix3},
     {"603tcf",                  cputables_Celeron_Cyrix3},
     {"vpc2007",                 cputables_PentiumIID_Celeron},

From 2fdda7bd4720d58df5e11264128b7cbcac18b27f Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 25 Jul 2021 22:46:51 -0300
Subject: [PATCH 24/52] Migrate enhanced Am486 to a standard naming convention

---
 src/config.c        | 7 ++++++-
 src/cpu/cpu_table.c | 4 ++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/src/config.c b/src/config.c
index f9347a0a4..cf66f160b 100644
--- a/src/config.c
+++ b/src/config.c
@@ -687,7 +687,12 @@ load_machine(void)
     cpu_f = NULL;
     p = config_get_string(cat, "cpu_family", NULL);
     if (p) {
-	cpu_f = cpu_get_family(p);
+	if (! strcmp(p, "enh_am486dx2")) /* migrate modified names */
+		cpu_f = cpu_get_family("am486dx2_slenh");
+	else if (! strcmp(p, "enh_am486dx4")) /* migrate modified names */
+		cpu_f = cpu_get_family("am486dx4_slenh");
+	else
+		cpu_f = cpu_get_family(p);
 
 	if (cpu_f && !cpu_family_is_eligible(cpu_f, machine)) /* only honor eligible families */
 		cpu_f = NULL;
diff --git a/src/cpu/cpu_table.c b/src/cpu/cpu_table.c
index b980c5cf0..0bc66e1c1 100644
--- a/src/cpu/cpu_table.c
+++ b/src/cpu/cpu_table.c
@@ -493,7 +493,7 @@ const cpu_family_t cpu_families[] = {
 	.package = CPU_PKG_SOCKET3,
 	.manufacturer = "AMD",
 	.name = "Am486DX2 (Enhanced)",
-	.internal_name = "enh_am486dx2",
+	.internal_name = "am486dx2_slenh",
 	.cpus = (const CPU[]) {
 		{"66",  CPU_ENH_Am486DX, fpus_internal, 66666666, 2, 5000, 0x435, 0x435, 0, CPU_SUPPORTS_DYNAREC, 12,12, 6, 6, 8},
 		{"80",  CPU_ENH_Am486DX, fpus_internal, 80000000, 2, 5000, 0x435, 0x435, 0, CPU_SUPPORTS_DYNAREC, 14,14, 6, 6, 10},
@@ -503,7 +503,7 @@ const cpu_family_t cpu_families[] = {
 	.package = CPU_PKG_SOCKET3,
 	.manufacturer = "AMD",
 	.name = "Am486DX4 (Enhanced)",
-	.internal_name = "enh_am486dx4",
+	.internal_name = "am486dx4_slenh",
 	.cpus = (const CPU[]) {
 		{"75",  CPU_ENH_Am486DX, fpus_internal,   75000000, 3.0, 5000, 0x482, 0x482, 0, CPU_SUPPORTS_DYNAREC, 12,12, 9, 9, 9},
 		{"100", CPU_ENH_Am486DX, fpus_internal,  100000000, 3.0, 5000, 0x482, 0x482, 0, CPU_SUPPORTS_DYNAREC, 15,15, 9, 9, 12},

From 45ebe545444a7e6242f88e9e3ab1e43279cb3f41 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 25 Jul 2021 22:48:04 -0300
Subject: [PATCH 25/52] Fix CPU table formatting

---
 src/cpu/cpu_table.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/src/cpu/cpu_table.c b/src/cpu/cpu_table.c
index 0bc66e1c1..57aa3f7ca 100644
--- a/src/cpu/cpu_table.c
+++ b/src/cpu/cpu_table.c
@@ -316,8 +316,7 @@ const cpu_family_t cpu_families[] = {
 		{"33",            CPU_i486SX,     fpus_486sx,  33333333, 1,  5000, 0x422,        0, 0, CPU_SUPPORTS_DYNAREC,  6, 6,3,3,  4},
 		{"", 0}
 	}
-    },
-	{
+    }, {
 	.package = CPU_PKG_SOCKET1,
 	.manufacturer = "Intel",
 	.name = "i486SX (SL-Enhanced)",
@@ -327,8 +326,7 @@ const cpu_family_t cpu_families[] = {
 		{"33",            CPU_i486SX_SLENH,     fpus_486sx,  33333333, 1,  5000, 0x42a,    0x42a, 0, CPU_SUPPORTS_DYNAREC,  6, 6,3,3,  4},
 		{"", 0}
 	}
-    },    
-	{
+    }, {
 	.package = CPU_PKG_SOCKET1,
 	.manufacturer = "Intel",
 	.name = "i486SX2",
@@ -349,8 +347,7 @@ const cpu_family_t cpu_families[] = {
 		{"50",            CPU_i486DX,  fpus_internal,  50000000, 1,  5000, 0x411,        0, 0, CPU_SUPPORTS_DYNAREC,  8, 8,4,4,  6},
 		{"", 0}
 	}
-    }, 
-     {
+    }, {
 	.package = CPU_PKG_SOCKET1,
 	.manufacturer = "Intel",
 	.name = "i486DX (SL-Enhanced)",
@@ -371,8 +368,7 @@ const cpu_family_t cpu_families[] = {
 		{"66",           CPU_i486DX, fpus_internal,  66666666, 2,  5000, 0x433,        0, 0, CPU_SUPPORTS_DYNAREC, 12,12,6,6,  8},
 		{"", 0}
 	}
-    }, 
- {
+    }, {
 	.package = CPU_PKG_SOCKET1,
 	.manufacturer = "Intel",
 	.name = "i486DX2 (SL-Enhanced)",
@@ -383,7 +379,7 @@ const cpu_family_t cpu_families[] = {
 		{"66",           CPU_i486DX_SLENH, fpus_internal,  66666666, 2,  5000, 0x435,    0x435, 0, CPU_SUPPORTS_DYNAREC, 12,12,6,6,  8},
 		{"", 0}
 	}
-    },     {
+    }, {
 	.package = CPU_PKG_SOCKET3_PC330,
 	.manufacturer = "Intel",
 	.name = "i486DX2",
@@ -454,8 +450,7 @@ const cpu_family_t cpu_families[] = {
 		{"80",  CPU_Am486DX, fpus_internal, 80000000, 2, 5000, 0x432,     0, 0, CPU_SUPPORTS_DYNAREC, 14,14, 6, 6, 10},
 		{"", 0}
 	}
-    }, 
- {
+    }, {
 	.package = CPU_PKG_SOCKET1,
 	.manufacturer = "AMD",
 	.name = "Am486DXL",

From 42eada3122d575ad039f596773c0d6c4d0732383 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Sun, 25 Jul 2021 22:58:03 -0300
Subject: [PATCH 26/52] VIA AC97 improvements, almost ready

---
 src/chipset/via_pipc.c       |   5 +
 src/include/86box/snd_ac97.h |   1 +
 src/sound/snd_ac97_via.c     | 197 ++++++++++++++++++++++-------------
 3 files changed, 129 insertions(+), 74 deletions(-)

diff --git a/src/chipset/via_pipc.c b/src/chipset/via_pipc.c
index 7c8757b81..85b36bf8b 100644
--- a/src/chipset/via_pipc.c
+++ b/src/chipset/via_pipc.c
@@ -1223,6 +1223,11 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 				dev->ac97_regs[func][addr] = val;
 			break;
 
+		case 0x41:
+			dev->ac97_regs[func][addr] = val;
+			ac97_via_write_control(dev->ac97, func, val);
+			break;
+
 		case 0x42: case 0x4a: case 0x4b:
 			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val;
 			gameport_remap(dev->gameport, (dev->ac97_regs[0][0x42] & 0x08) ? ((dev->ac97_regs[0][0x4b] << 8) | dev->ac97_regs[0][0x4a]) : 0);
diff --git a/src/include/86box/snd_ac97.h b/src/include/86box/snd_ac97.h
index da2bb8b95..d8f165dbd 100644
--- a/src/include/86box/snd_ac97.h
+++ b/src/include/86box/snd_ac97.h
@@ -30,6 +30,7 @@ extern void	ac97_codec_reset(void *priv);
 
 extern void	ac97_via_set_slot(void *priv, int slot, int irq_pin);
 extern uint8_t	ac97_via_read_status(void *priv, uint8_t modem);
+extern void	ac97_via_write_control(void *priv, uint8_t modem, uint8_t val);
 extern void	ac97_via_remap_audio_sgd(void *priv, uint16_t new_io_base, uint8_t enable);
 extern void	ac97_via_remap_modem_sgd(void *priv, uint16_t new_io_base, uint8_t enable);
 extern void	ac97_via_remap_audio_codec(void *priv, uint16_t new_io_base, uint8_t enable);
diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 8ddc590a4..44b9ad825 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -32,7 +32,7 @@
 
 
 typedef struct {
-    uint8_t	id;
+    uint8_t	id, always_run;
     struct _ac97_via_ *dev;
 
     uint32_t	entry_ptr, sample_ptr, fifo_pos, fifo_end;
@@ -44,7 +44,13 @@ typedef struct {
 
 typedef struct _ac97_via_ {
     uint16_t	audio_sgd_base, audio_codec_base, modem_sgd_base, modem_codec_base;
-    uint8_t	sgd_regs[256], irq_stuck;
+    uint8_t	sgd_regs[256], pcm_enabled: 1, fm_enabled: 1;
+    struct {
+	union {
+		uint8_t regs_codec[2][128];
+		uint8_t regs_linear[256];
+	};
+    } codec_shadow[2];
     int		slot, irq_pin;
 
     ac97_codec_t *codec[2][2];
@@ -61,7 +67,6 @@ typedef struct _ac97_via_ {
 #define ENABLE_AC97_VIA_LOG 1
 #ifdef ENABLE_AC97_VIA_LOG
 int ac97_via_do_log = ENABLE_AC97_VIA_LOG;
-unsigned int ac97_via_lost_irqs = 0;
 
 static void
 ac97_via_log(const char *fmt, ...)
@@ -112,19 +117,54 @@ ac97_via_read_status(void *priv, uint8_t modem)
 }
 
 
-static void
-ac97_via_update_irqs(ac97_via_t *dev, uint8_t iflag_clear)
+void
+ac97_via_write_control(void *priv, uint8_t modem, uint8_t val)
 {
-    uint8_t do_irq = 0;
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    uint8_t i;
 
-    /* Check interrupt flags on all SGDs. */
-    for (uint8_t i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++)
-	do_irq |= (dev->sgd_regs[i << 4] & (dev->sgd_regs[(i << 4) | 0x02] & 0x03));
+    ac97_via_log("AC97 VIA %d: write_control(%02X)\n", modem, val);
 
-    if (do_irq)
-	pci_set_irq(dev->slot, dev->irq_pin);
-    else
-	pci_clear_irq(dev->slot, dev->irq_pin);
+    /* Reset codecs if requested. */
+    if (val & 0x40) {
+	for (i = 0; i <= 1; i++) {
+		if (dev->codec[modem][i])
+			ac97_codec_reset(dev->codec[modem][i]);
+	}
+    }
+
+    if (!modem) {
+    	/* Start or stop PCM playback. */
+	i = (val & 0xf4) == 0xc4;
+	if (i && !dev->pcm_enabled)
+		timer_advance_u64(&dev->timer_count, dev->timer_latch);
+	dev->pcm_enabled = i;
+
+	/* Start or stop FM playback. */
+	i = (val & 0xf2) == 0xc2;
+	if (i && !dev->fm_enabled)
+		timer_advance_u64(&dev->timer_count_fm, dev->timer_latch);
+	dev->fm_enabled = i;
+    }
+}
+
+
+static void
+ac97_via_update_irqs(ac97_via_t *dev)
+{
+    /* Check interrupt flags in all SGDs. */
+    uint8_t i, sgd_id;
+    for (i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++) {
+	sgd_id = i << 4;
+	/* Stop immediately if any flag is set. Doing it this way optimizes
+	   rising edges for the playback SGD (0 - first to be checked). */
+	if (dev->sgd_regs[sgd_id] & (dev->sgd_regs[sgd_id | 0x2] & 0x03)) {
+		pci_set_irq(dev->slot, dev->irq_pin);
+		return;
+	}
+    }
+
+    pci_clear_irq(dev->slot, dev->irq_pin);
 }
 
 
@@ -245,12 +285,10 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 	switch (addr & 0xf) {
 		case 0x0:
 			/* Clear RWC status bits. */
-			for (i = 0x01; i <= 0x04; i <<= 1) {
-				if (val & i)
-					dev->sgd_regs[addr] &= ~i;
-			}
+			dev->sgd_regs[addr] &= ~(val & 0x07);
 
-			ac97_via_update_irqs(dev, 1);
+			/* Update status interrupts. */
+			ac97_via_update_irqs(dev);
 
 			return;
 
@@ -258,7 +296,7 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 			/* Start SGD if requested. */
 			if (val & 0x80) {
 				if (dev->sgd_regs[addr & 0xf0] & 0x80) {
-					/* Queue SGD trigger. */
+					/* Queue SGD trigger if already running. */
 					dev->sgd_regs[addr & 0xf0] |= 0x08;
 				} else {
 					/* Start SGD immediately. */
@@ -271,7 +309,7 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 					dev->sgd[addr >> 4].restart = 1;
 
 					/* Start the actual SGD process. */
-					timer_advance_u64(&dev->sgd[addr >> 4].timer, 0);
+					ac97_via_sgd_process(&dev->sgd[addr >> 4]);
 				}
 			}
 			/* Stop SGD if requested. */
@@ -314,11 +352,15 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 			/* Read from or write to codec. */
 			if (codec) {
 				if (val & 0x80) {
-					dev->sgd_regs[0x80] = ac97_codec_read(codec, val & 0x7e);
-					dev->sgd_regs[0x81] = ac97_codec_read(codec, (val & 0x7e) | 1);
+					val &= 0x7e;
+					dev->sgd_regs[0x80] = dev->codec_shadow[modem].regs_codec[i][val] = ac97_codec_read(codec, val);
+					val |= 1;
+					dev->sgd_regs[0x81] = dev->codec_shadow[modem].regs_codec[i][val] = ac97_codec_read(codec, val);
 				} else {
-					ac97_codec_write(codec, val & 0x7e, dev->sgd_regs[0x80]);
-					ac97_codec_write(codec, (val & 0x7e) | 1, dev->sgd_regs[0x81]);
+					val &= 0x7e;
+					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x80]);
+					val |= 1;
+					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x81]);
 				}
 
 				/* Flag data/status/index for this codec as valid. */
@@ -330,23 +372,12 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 			break;
 
 		case 0x83:
-			val &= 0xca;
-
-			/* Clear RWC bits. */
-			for (i = 0x02; i <= 0x08; i <<= 2) {
-#if 0 /* race condition with Linux clearing bits and starting SGD on the same dword write */
-				if (val & i)
-					val &= ~i;
-				else
-					val |= dev->sgd_regs[addr] & i;
+			/* Clear RWC status bits. */
+#if 0 /* race condition with Linux accessing a register and clearing status bits on the same dword write */
+			val = (dev->sgd_regs[addr] & ~(val & 0x0a)) | (val & 0xc0);
 #else
-				/* Don't flag data/status/index as valid if the codec is absent. */
-				if (dev->codec[modem][!!(val & 0x40)])
-					val |= i;
-				else
-					val &= ~i;
+			val = dev->sgd_regs[addr] | 0x0a | (val & 0xc0);
 #endif
-			}
 			break;
 	}
     }
@@ -393,10 +424,7 @@ ac97_via_codec_read(uint16_t addr, void *priv)
     addr &= 0xff;
     uint8_t ret = 0xff;
 
-    /* Bit 7 selects secondary codec. */
-    ac97_codec_t *codec = dev->codec[modem][addr >> 7];
-    if (codec)
-	ret = ac97_codec_read(codec, addr & 0x7f);
+    ret = dev->codec_shadow[modem].regs_linear[addr];
 
     ac97_via_log("AC97 VIA %d: codec_read(%02X) = %02X\n", modem, addr, ret);
 
@@ -413,10 +441,8 @@ ac97_via_codec_write(uint16_t addr, uint8_t val, void *priv)
 
     ac97_via_log("AC97 VIA %d: codec_write(%02X, %02X)\n", modem, addr, val);
 
-    /* Bit 7 selects secondary codec. */
-    ac97_codec_t *codec = dev->codec[modem][addr >> 7];
-    if (codec)
-	ac97_codec_write(codec, addr & 0x7f, val);
+    /* Unknown behavior, maybe it does write to the shadow registers? */
+    dev->codec_shadow[modem].regs_linear[addr] = val;
 }
 
 
@@ -476,11 +502,19 @@ ac97_via_sgd_process(void *priv)
     ac97_via_sgd_t *sgd = (ac97_via_sgd_t *) priv;
     ac97_via_t *dev = sgd->dev;
 
-    /* Process SGD if active, unless this is Audio Read and there's no room in the FIFO. */
-    if (((dev->sgd_regs[sgd->id] & 0xc4) == 0x80) && (sgd->id || ((sgd->fifo_end - sgd->fifo_pos) <= (sizeof(sgd->fifo) - 4)))) {
+    /* Stop if this SGD is not active. */
+    uint8_t sgd_status = dev->sgd_regs[sgd->id] & 0xc4;
+    if (!(sgd_status & 0x80))
+	return;
+
+    /* Schedule next run. */
+    timer_advance_u64(&sgd->timer, dev->timer_fifo_latch);
+
+    /* Process SGD if it's active, and the FIFO has room or is disabled. */
+    if ((sgd_status == 0x80) && (sgd->always_run || ((sgd->fifo_end - sgd->fifo_pos) <= (sizeof(sgd->fifo) - 4)))) {
 	/* Move on to the next block if no entry is present. */
-    	if (sgd->restart) {
-    		sgd->restart = 0;
+	if (sgd->restart) {
+		sgd->restart = 0;
 
 		/* Start at first entry if no pointer is present. */
 		if (!sgd->entry_ptr)
@@ -502,8 +536,8 @@ ac97_via_sgd_process(void *priv)
 		sgd->entry_flags = sgd->sample_count >> 24;
 		sgd->sample_count &= 0xffffff;
 
-		ac97_via_log("AC97 VIA: Starting SGD %d block at %08X start %08X len %06X flags %02X lostirqs %d\n", sgd->id >> 4,
-			     sgd->entry_ptr - 8, sgd->sample_ptr, sgd->sample_count, sgd->entry_flags, ac97_via_lost_irqs);
+		ac97_via_log("AC97 VIA: Starting SGD %d block at %08X start %08X len %06X flags %02X\n", sgd->id >> 4,
+			     sgd->entry_ptr - 8, sgd->sample_ptr, sgd->sample_count, sgd->entry_flags);
 	}
 
 	if (sgd->id & 0x10) {
@@ -557,8 +591,7 @@ ac97_via_sgd_process(void *priv)
 				dev->sgd_regs[sgd->id] &= ~0x08;
 
 				/* Go back to the starting block. */
-				//sgd->entry_ptr = *((uint32_t *) &dev->sgd_regs[sgd->id | 0x4]) & 0xfffffffe; /* why does XP not like this? */
-				sgd->entry_ptr = 0;
+				sgd->entry_ptr = 0; /* ugly, but Windows XP plays too fast if the pointer is reloaded now */
 			} else {
 				ac97_via_log(" finish");
 
@@ -568,16 +601,13 @@ ac97_via_sgd_process(void *priv)
 		}
 		ac97_via_log("\n");
 
+		/* Fire any requested status interrupts. */
+		ac97_via_update_irqs(dev);
+
 		/* Move on to a new block on the next run. */
 		sgd->restart = 1;
 	}
     }
-
-    ac97_via_update_irqs(dev, 0);
-
-    /* Continue SGD processing if active or an interrupt is pending. */
-    if (dev->sgd_regs[sgd->id] & (0x80 | (dev->sgd_regs[sgd->id | 0x02] & 0x03)))
-	timer_advance_u64(&sgd->timer, dev->timer_fifo_latch);
 }
 
 
@@ -587,22 +617,27 @@ ac97_via_poll(void *priv)
     ac97_via_t *dev = (ac97_via_t *) priv;
     ac97_via_sgd_t *sgd = &dev->sgd[0]; /* Audio Read */
 
-    timer_advance_u64(&dev->timer_count, dev->timer_latch);
+    /* Schedule next run if PCM playback is enabled. */
+    if (dev->pcm_enabled)
+	timer_advance_u64(&dev->timer_count, dev->timer_latch);
 
+    /* Update audio buffer. */
     ac97_via_update(dev);
 
-    dev->out_l = dev->out_r = 0;
-
+    /* Feed next sample from the FIFO. */
     switch (dev->sgd_regs[0x02] & 0x30) {
 	case 0x00: /* Mono, 8-bit PCM */
-		if ((sgd->fifo_end - sgd->fifo_pos) >= 1)
+		if ((sgd->fifo_end - sgd->fifo_pos) >= 1) {
 			dev->out_l = dev->out_r = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+			return;
+		}
 		break;
 
 	case 0x10: /* Stereo, 8-bit PCM */
 		if ((sgd->fifo_end - sgd->fifo_pos) >= 2) {
 			dev->out_l = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
 			dev->out_r = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+			return;
 		}
 		break;
 
@@ -610,6 +645,7 @@ ac97_via_poll(void *priv)
 		if ((sgd->fifo_end - sgd->fifo_pos) >= 2) {
 			dev->out_l = dev->out_r = *((uint16_t *) &sgd->fifo[sgd->fifo_pos & (sizeof(sgd->fifo) - 1)]);
 			sgd->fifo_pos += 2;
+			return;
 		}
 		break;
 
@@ -619,9 +655,13 @@ ac97_via_poll(void *priv)
 			sgd->fifo_pos += 2;
 			dev->out_r = *((uint16_t *) &sgd->fifo[sgd->fifo_pos & (sizeof(sgd->fifo) - 1)]);
 			sgd->fifo_pos += 2;
+			return;
 		}
 		break;
     }
+
+    /* Feed silence if the FIFO is empty. */
+    dev->out_l = dev->out_r = 0;
 }
 
 
@@ -631,17 +671,23 @@ ac97_via_poll_fm(void *priv)
     ac97_via_t *dev = (ac97_via_t *) priv;
     ac97_via_sgd_t *sgd = &dev->sgd[2]; /* FM Read */
 
-    timer_advance_u64(&dev->timer_count_fm, dev->timer_latch);
+    /* Schedule next run if FM playback is enabled. */
+    if (dev->fm_enabled)
+	timer_advance_u64(&dev->timer_count_fm, dev->timer_latch);
 
+    /* Update FM audio buffer. */
     ac97_via_update_fm(dev);
 
-    dev->fm_out_l = dev->fm_out_r = 0;
-
-    /* Unknown format, assumed. */
+    /* Feed next sample from the FIFO.
+       Unknown data format assumed to be 8-bit stereo. */
     if ((sgd->fifo_end - sgd->fifo_pos) >= 2) {
-	dev->out_l = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
-	dev->out_r = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+	dev->fm_out_l = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+	dev->fm_out_r = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+	return;
     }
+
+    /* Feed silence if the FIFO is empty. */
+    dev->fm_out_l = dev->fm_out_r = 0;
 }
 
 
@@ -654,10 +700,11 @@ ac97_via_get_buffer(int32_t *buffer, int len, void *priv)
     ac97_via_update_fm(dev);
 
     for (int c = 0; c < len * 2; c++) {
-	buffer[c] += dev->buffer[c];
+	buffer[c] += dev->buffer[c] / 2;
 	buffer[c] += dev->fm_buffer[c];
     }
 
+    /* Feed silence if the FIFO is empty. */
     dev->pos = dev->fm_pos = 0;
 }
 
@@ -689,6 +736,10 @@ ac97_via_init(const device_t *info)
 	dev->sgd[i].id = i << 4;
 	dev->sgd[i].dev = dev;
 
+	/* Disable the FIFO on SGDs we don't care about. */
+	if ((i != 0) && (i != 2))
+		dev->sgd[i].always_run = 1;
+
 	timer_add(&dev->sgd[i].timer, ac97_via_sgd_process, &dev->sgd[i], 0);
     }
 
@@ -696,8 +747,6 @@ ac97_via_init(const device_t *info)
     timer_add(&dev->timer_count, ac97_via_poll, dev, 0);
     timer_add(&dev->timer_count_fm, ac97_via_poll_fm, dev, 0);
     ac97_via_speed_changed(dev);
-    timer_advance_u64(&dev->timer_count, dev->timer_latch);
-    timer_advance_u64(&dev->timer_count_fm, dev->timer_latch);
 
     /* Set up playback handler. */
     sound_add_handler(ac97_via_get_buffer, dev);

From 70285df61b19d4232853ef7ec6d7644176d52d58 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Mon, 26 Jul 2021 00:19:39 -0300
Subject: [PATCH 27/52] The start of AC97 volume control

---
 src/include/86box/snd_ac97.h |  1 +
 src/sound/snd_ac97_codec.c   | 34 +++++++++++++++++++++++++++++
 src/sound/snd_ac97_via.c     | 42 ++++++++++++++++++++++++++----------
 src/sound/snd_audiopci.c     | 41 +++++++----------------------------
 4 files changed, 74 insertions(+), 44 deletions(-)

diff --git a/src/include/86box/snd_ac97.h b/src/include/86box/snd_ac97.h
index d8f165dbd..a72a874d9 100644
--- a/src/include/86box/snd_ac97.h
+++ b/src/include/86box/snd_ac97.h
@@ -27,6 +27,7 @@ typedef struct {
 extern uint8_t	ac97_codec_read(ac97_codec_t *dev, uint8_t reg);
 extern void	ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val);
 extern void	ac97_codec_reset(void *priv);
+extern void	ac97_codec_getattn(void *priv, uint8_t reg, int *l, int *r);
 
 extern void	ac97_via_set_slot(void *priv, int slot, int irq_pin);
 extern uint8_t	ac97_via_read_status(void *priv, uint8_t modem);
diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index 6a6d45f87..d215b8145 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -54,6 +54,11 @@ ac97_codec_log(const char *fmt, ...)
 #define ac97_codec_log(fmt, ...)
 #endif
 
+static const int32_t codec_attn[] = {
+      25,   32,   41,   51,   65,   82,  103,  130,  164,  206,   260,   327,   412,   519,   653,   822,
+    1036, 1304, 1641, 2067, 2602, 3276, 4125, 5192, 6537, 8230, 10362, 13044, 16422, 20674, 26027, 32767
+};
+
 ac97_codec_t	**ac97_codec = NULL, **ac97_modem_codec = NULL;
 int		ac97_codec_count = 0, ac97_modem_codec_count = 0;
 
@@ -182,6 +187,35 @@ ac97_codec_reset(void *priv)
 }
 
 
+void
+ac97_codec_getattn(void *priv, uint8_t reg, int *l, int *r)
+{
+    ac97_codec_t *dev = (ac97_codec_t *) priv;
+    uint8_t r_val = dev->regs[reg],
+	    l_val = dev->regs[reg | 1];
+
+    if (l_val & 0x80) { /* mute */
+	*l = 0;
+	*r = 0;
+	return;
+    }
+
+    if (reg < 0x10) { /* 6-bit volume */
+    	if (l_val & 0x20)
+    		*l = codec_attn[0];
+    	else
+    		*l = codec_attn[0x1f - (l_val & 0x1f)];
+    	if (r_val & 0x20)
+    		*r = codec_attn[0];
+    	else
+    		*r = codec_attn[0x1f - (r_val & 0x1f)];
+    } else { /* 5-bit gain */
+    	*l = codec_attn[0x1f - (l_val & 0x1f)];
+	*r = codec_attn[0x1f - (r_val & 0x1f)];
+    }
+}
+
+
 static void *
 ac97_codec_init(const device_t *info)
 {
diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 44b9ad825..bc2ec8ee9 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -59,12 +59,12 @@ typedef struct _ac97_via_ {
     pc_timer_t	timer_count, timer_count_fm;
     uint64_t	timer_latch, timer_fifo_latch;
     int16_t	out_l, out_r, fm_out_l, fm_out_r;
-    double	cd_vol_l, cd_vol_r;
-    int16_t	buffer[SOUNDBUFLEN * 2], fm_buffer[SOUNDBUFLEN * 2];
+    int		master_vol_l, master_vol_r, pcm_vol_l, pcm_vol_r, cd_vol_l, cd_vol_r;
+    int32_t	buffer[SOUNDBUFLEN * 2], fm_buffer[SOUNDBUFLEN * 2];
     int		pos, fm_pos;
 } ac97_via_t;
 
-#define ENABLE_AC97_VIA_LOG 1
+
 #ifdef ENABLE_AC97_VIA_LOG
 int ac97_via_do_log = ENABLE_AC97_VIA_LOG;
 
@@ -85,6 +85,7 @@ ac97_via_log(const char *fmt, ...)
 
 
 static void	ac97_via_sgd_process(void *priv);
+static void	ac97_via_update_volumes(ac97_via_t *dev, ac97_codec_t *codec);
 
 
 void
@@ -125,11 +126,15 @@ ac97_via_write_control(void *priv, uint8_t modem, uint8_t val)
 
     ac97_via_log("AC97 VIA %d: write_control(%02X)\n", modem, val);
 
-    /* Reset codecs if requested. */
-    if (val & 0x40) {
-	for (i = 0; i <= 1; i++) {
-		if (dev->codec[modem][i])
+    /* Reset and/or update volumes on all codecs. */
+    for (i = 0; i <= 1; i++) {
+	if (dev->codec[modem][i]) {
+		/* Reset codec if requested. */
+		if (val & 0x40)
 			ac97_codec_reset(dev->codec[modem][i]);
+
+		/* Update volumes. */
+		ac97_via_update_volumes(dev, dev->codec[modem][i]);
 	}
     }
 
@@ -168,6 +173,16 @@ ac97_via_update_irqs(ac97_via_t *dev)
 }
 
 
+static void
+ac97_via_update_volumes(ac97_via_t *dev, ac97_codec_t *codec) {
+    ac97_codec_getattn(codec, 0x02, &dev->master_vol_l, &dev->master_vol_r);
+    ac97_codec_getattn(codec, 0x18, &dev->pcm_vol_l, &dev->pcm_vol_r);
+    ac97_codec_getattn(codec, 0x12, &dev->cd_vol_l, &dev->cd_vol_r);
+
+    pclog("master %d %d\npcm %d %d\ncd %d %d\n", dev->master_vol_l, dev->master_vol_r, dev->pcm_vol_l, dev->pcm_vol_r, dev->cd_vol_l, dev->cd_vol_r);
+}
+
+
 uint8_t
 ac97_via_sgd_read(uint16_t addr, void *priv)
 {
@@ -361,6 +376,9 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x80]);
 					val |= 1;
 					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x81]);
+
+					/* Update volumes. */
+					ac97_via_update_volumes(dev, codec);
 				}
 
 				/* Flag data/status/index for this codec as valid. */
@@ -479,9 +497,12 @@ ac97_via_remap_modem_codec(void *priv, uint16_t new_io_base, uint8_t enable)
 static void
 ac97_via_update(ac97_via_t *dev)
 {
+    int32_t l = (((dev->out_l * dev->pcm_vol_l) >> 15) * dev->master_vol_l) >> 15,
+	    r = (((dev->out_r * dev->pcm_vol_r) >> 15) * dev->master_vol_r) >> 15;
+
     for (; dev->pos < sound_pos_global; dev->pos++) {
-	dev->buffer[dev->pos*2]     = dev->out_l;
-	dev->buffer[dev->pos*2 + 1] = dev->out_r;
+	dev->buffer[dev->pos*2]     = l;
+	dev->buffer[dev->pos*2 + 1] = r;
     }
 }
 
@@ -701,10 +722,9 @@ ac97_via_get_buffer(int32_t *buffer, int len, void *priv)
 
     for (int c = 0; c < len * 2; c++) {
 	buffer[c] += dev->buffer[c] / 2;
-	buffer[c] += dev->fm_buffer[c];
+	buffer[c] += dev->fm_buffer[c] / 2;
     }
 
-    /* Feed silence if the FIFO is empty. */
     dev->pos = dev->fm_pos = 0;
 }
 
diff --git a/src/sound/snd_audiopci.c b/src/sound/snd_audiopci.c
index d64066ccc..cd8288d4d 100644
--- a/src/sound/snd_audiopci.c
+++ b/src/sound/snd_audiopci.c
@@ -148,12 +148,6 @@ typedef struct {
 #define FORMAT_MONO_16			2
 #define FORMAT_STEREO_16		3
 
-const int32_t codec_attn[]= {
-	25,32,41,51,65,82,103,130,164,206,260,327,412,519,653,
-	822,1036,1304,1641,2067,2602,3276,4125,5192,6537,8230,10362,13044,
-	16422,20674,26027,32767
-};
-
 static void es1371_fetch(es1371_t *es1371, int dac_nr);
 static void update_legacy(es1371_t *es1371, uint32_t old_legacy_ctrl);
 
@@ -595,35 +589,16 @@ static void es1371_outl(uint16_t port, uint32_t val, void *p)
 		case 0x14:
 		if (val & CODEC_READ) {
 			es1371->codec_ctrl &= 0x00ff0000;
-			es1371->codec_ctrl |= ac97_codec_read(es1371->codec, (val >> 16) & 0x7f);
-			es1371->codec_ctrl |= ac97_codec_read(es1371->codec, ((val >> 16) & 0x7f) + 1) << 8;
+			val = (val >> 16) & 0x7e;
+			es1371->codec_ctrl |= ac97_codec_read(es1371->codec, val);
+			es1371->codec_ctrl |= ac97_codec_read(es1371->codec, val | 1) << 8;
 		} else {
-			es1371->codec_ctrl &= 0x00ffffff;
-			ac97_codec_write(es1371->codec, (val >> 16) & 0x7f, val & 0xff);
-			ac97_codec_write(es1371->codec, ((val >> 16) & 0x7f) + 1, val >> 8);
+			es1371->codec_ctrl = val & 0x00ffffff;
+			ac97_codec_write(es1371->codec,  (val >> 16) & 0x7e,      val & 0xff);
+			ac97_codec_write(es1371->codec, ((val >> 16) & 0x7e) | 1, val >> 8);
 
-			val = *((uint16_t *) &es1371->codec->regs[0x02]); /* Master Volume */
-			if (val & 0x8000) {
-				es1371->master_vol_l = es1371->master_vol_r = 0;
-			} else {
-				if (val & 0x2000)
-					es1371->master_vol_l = codec_attn[0];
-				else
-					es1371->master_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
-				if (val & 0x20)
-					es1371->master_vol_r = codec_attn[0];
-				else
-					es1371->master_vol_r = codec_attn[0x1f - (val & 0x1f)];
-			}
-
-			val = *((uint16_t *) &es1371->codec->regs[0x12]); /* CD Volume */
-			if (val & 0x8000) {
-				es1371->cd_vol_l = es1371->cd_vol_r = 0;
-			} else {
-				es1371->cd_vol_l = codec_attn[0x1f - ((val >> 8) & 0x1f)];
-				es1371->cd_vol_r = codec_attn[0x1f - (val & 0x1f)];
-			}
-			break;
+			ac97_codec_getattn(es1371->codec, 0x02, &es1371->master_vol_l, &es1371->master_vol_r);
+			ac97_codec_getattn(es1371->codec, 0x12, &es1371->cd_vol_l, &es1371->cd_vol_r);
 		}
 		break;
 		

From 35d0aa0df4c5ad2f58f17db70943cd8f0c2c06c0 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 27 Jul 2021 16:01:17 -0300
Subject: [PATCH 28/52] Change VIA FM and other behavior to match real
 hardware, and add "real fake OPL" mode

---
 src/chipset/via_pipc.c | 111 ++++++++++++++++-------------------------
 1 file changed, 42 insertions(+), 69 deletions(-)

diff --git a/src/chipset/via_pipc.c b/src/chipset/via_pipc.c
index 85b36bf8b..18c3296a1 100644
--- a/src/chipset/via_pipc.c
+++ b/src/chipset/via_pipc.c
@@ -75,7 +75,7 @@ typedef struct
 		ide_regs[256],
 		usb_regs[2][256],
 		power_regs[256],
-		ac97_regs[2][256], fmnmi_regs[4], fm_regs[4];
+		ac97_regs[2][256], fmnmi_regs[4];
     sff8038i_t	*bm[2];
     nvr_t	*nvr;
     int		nvr_enabled, slot;
@@ -475,30 +475,10 @@ static uint8_t
 pipc_midigame_read(uint16_t addr, void *priv)
 {
     pipc_t *dev = (pipc_t *) priv;
-    uint8_t ret = 0xff;
 
-    addr &= 0x03;
-    switch (addr) {
-	case 0x02: case 0x03:
-		ret = pipc_read(5, 0x48 + addr, dev);
-		break;
-    }
-
-    return ret;
-}
-
-
-static void
-pipc_midigame_write(uint16_t addr, uint8_t val, void *priv)
-{
-    pipc_t *dev = (pipc_t *) priv;
-
-    addr &= 0x03;
-    switch (addr) {
-	case 0x02: case 0x03:
-		pipc_write(5, 0x48 + addr, val, dev);
-		break;
-    }
+    /* This BAR apparently doesn't work at all on a real 686B. It doesn't react to writes,
+       and reads always return 0x80 or 0xff depending on AC97 audio register 0x42 bit 7. */
+    return (dev->ac97_regs[0][0x42] & 0x80) ? 0x80 : 0xff;
 }
 
 
@@ -509,12 +489,12 @@ pipc_midigame_handlers(pipc_t *dev, uint8_t modem)
 	return;
 
     if (dev->midigame_base)
-	io_removehandler(dev->midigame_base, 4, pipc_midigame_read, NULL, NULL, pipc_midigame_write, NULL, NULL, dev);
+	io_removehandler(dev->midigame_base, 4, pipc_midigame_read, NULL, NULL, NULL, NULL, NULL, dev);
 
     dev->midigame_base = (dev->ac97_regs[0][0x19] << 8) | (dev->ac97_regs[0][0x18] & 0xfc);
 
     if (dev->midigame_base && (dev->ac97_regs[0][0x04] & PCI_COMMAND_IO))
-	io_sethandler(dev->midigame_base, 4, pipc_midigame_read, NULL, NULL, pipc_midigame_write, NULL, NULL, dev);
+	io_sethandler(dev->midigame_base, 4, pipc_midigame_read, NULL, NULL, NULL, NULL, NULL, dev);
 }
 
 
@@ -539,31 +519,29 @@ pipc_fmnmi_read(uint16_t addr, void *priv)
 
     pipc_log("PIPC: fmnmi_read(%02X) = %02X\n", addr & 0x03, ret);
 
-    if (dev->ac97_regs[0][0x48] & 0x04)
-	smi_line = 0;
-    else
-	nmi = 0;
-
-    return ret;
-}
-
-
-static void
-pipc_fmnmi_write(uint16_t addr, uint8_t val, void *priv)
-{
-#ifdef ENABLE_PIPC_LOG
-    pipc_t *dev = (pipc_t *) priv;
+#ifdef VIA_PIPC_FM_EMULATION
+    /* Clear NMI/SMI if enabled. */
+    if  (dev->ac97_regs[0][0x48] & 0x01) {
+	if (dev->ac97_regs[0][0x48] & 0x04)
+		smi_line = 0;
+	else
+		nmi = 0;
+    }
 #endif
 
-    pipc_log("PIPC: fmnmi_write(%02X, %02X)\n", addr & 0x03, val);
+    return ret;
 }
 
 
 static uint8_t
 pipc_fm_read(uint16_t addr, void *priv)
 {
+#ifdef VIA_PIPC_FM_EMULATION
+    uint8_t ret = 0x00;
+#else
     pipc_t *dev = (pipc_t *) priv;
     uint8_t ret = opl3_read(addr, &dev->sb->opl);
+#endif
 
     pipc_log("PIPC: fm_read(%02X) = %02X\n", addr & 0x03, ret);
 
@@ -578,17 +556,26 @@ pipc_fm_write(uint16_t addr, uint8_t val, void *priv)
 
     pipc_log("PIPC: fm_write(%02X, %02X)\n", addr & 0x03, val);
 
+#ifdef VIA_PIPC_FM_EMULATION
+    /* Real 686B only updates the bank ID register when writing to the
+       index port, and only fires NMI/SMI when writing to the data port. */
+    if (!(addr & 0x01)) {
+	dev->fmnmi_regs[0x00] = (addr & 0x02) ? 0x02 : 0x01;
+	dev->fmnmi_regs[0x01] = val;
+    } else {
+	dev->fmnmi_regs[0x02] = val;
+
+	/* Fire NMI/SMI if enabled. */
+	if (dev->ac97_regs[0][0x48] & 0x01) {
+		if (dev->ac97_regs[0][0x48] & 0x04)
+			smi_line = 1;
+		else
+			nmi = 1;
+	}
+    }
+#else
     opl3_write(addr, val, &dev->sb->opl);
-    dev->fm_regs[addr & 0x03] = val;
-
-    dev->fmnmi_regs[0x00] = (addr & 0x02) ? 0x02 : 0x01;
-    dev->fmnmi_regs[0x01] = dev->fm_regs[addr & 0x02];
-    dev->fmnmi_regs[0x02] = dev->fm_regs[(addr & 0x02) | 0x01];
-
-    if (dev->ac97_regs[0][0x48] & 0x04)
-	smi_line = 1;
-    else
-	nmi = 1;
+#endif
 }
 
 
@@ -599,7 +586,7 @@ pipc_fmnmi_handlers(pipc_t *dev, uint8_t modem)
 	return;
 
     if (dev->fmnmi_base)
-	io_removehandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, pipc_fmnmi_write, NULL, NULL, dev);
+	io_removehandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, NULL, NULL, NULL, dev);
 
     if (dev->fm_enabled)
 	io_removehandler(0x388, 4, pipc_fm_read, NULL, NULL, pipc_fm_write, NULL, NULL, dev);
@@ -608,7 +595,7 @@ pipc_fmnmi_handlers(pipc_t *dev, uint8_t modem)
     dev->fm_enabled = !!(dev->ac97_regs[0][0x42] & 0x04);
 
     if (dev->fmnmi_base && (dev->ac97_regs[0][0x04] & PCI_COMMAND_IO))
-	io_sethandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, pipc_fmnmi_write, NULL, NULL, dev);
+	io_sethandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, NULL, NULL, NULL, dev);
 
     if (dev->fm_enabled)
 	io_sethandler(0x388, 4, pipc_fm_read, NULL, NULL, pipc_fm_write, NULL, NULL, dev);
@@ -1230,7 +1217,7 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 
 		case 0x42: case 0x4a: case 0x4b:
 			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val;
-			gameport_remap(dev->gameport, (dev->ac97_regs[0][0x42] & 0x08) ? ((dev->ac97_regs[0][0x4b] << 8) | dev->ac97_regs[0][0x4a]) : 0);
+			gameport_remap(dev->gameport, (dev->ac97_regs[0][0x42] & 0x08) ? ((dev->ac97_regs[0][0x4b] << 8) | (dev->ac97_regs[0][0x4a] & 0xf8)) : 0);
 			if (addr == 0x42)
 				pipc_fmnmi_handlers(dev, func);
 			break;
@@ -1243,24 +1230,10 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val & 0xf0;
 			break;
 
-		case 0x45:
+		case 0x45: case 0x48:
 			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val & 0x0f;
 			break;
 
-		case 0x48:
-			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val & 0x0f;
-			/*if (!(val & 0x01)) {
-				if (val & 0x04)
-					smi_line = 0;
-				else
-					nmi = 0;
-			}*/
-			if (val & 0x04)
-				smi_line = !!(val & 0x01);
-			else
-				nmi = !!(val & 0x01);
-			break;
-
 		default:
 			dev->ac97_regs[func][addr] = val;
 			break;

From 54b8fb57aa5ae3ca6ff1a0c73f13bf3d2282d5fb Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 27 Jul 2021 16:01:30 -0300
Subject: [PATCH 29/52] Add separate table for AC97 gain (not quite right)

---
 src/sound/snd_ac97_codec.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index d215b8145..5532a1441 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -58,6 +58,10 @@ static const int32_t codec_attn[] = {
       25,   32,   41,   51,   65,   82,  103,  130,  164,  206,   260,   327,   412,   519,   653,   822,
     1036, 1304, 1641, 2067, 2602, 3276, 4125, 5192, 6537, 8230, 10362, 13044, 16422, 20674, 26027, 32767
 };
+static const int32_t codec_gain[] = {
+    8545, 8552,  8561,  8571,  8585,  8602,  8623,  8650,  8684,  8726,  8780,  8847,  8932,  9039,  9173,  9342,
+    9556, 9824, 10161, 10587, 11122, 11796, 12645, 13712, 15057, 16750, 18882, 21564, 24942, 29194, 34547, 41287
+};
 
 ac97_codec_t	**ac97_codec = NULL, **ac97_modem_codec = NULL;
 int		ac97_codec_count = 0, ac97_modem_codec_count = 0;
@@ -210,8 +214,8 @@ ac97_codec_getattn(void *priv, uint8_t reg, int *l, int *r)
     	else
     		*r = codec_attn[0x1f - (r_val & 0x1f)];
     } else { /* 5-bit gain */
-    	*l = codec_attn[0x1f - (l_val & 0x1f)];
-	*r = codec_attn[0x1f - (r_val & 0x1f)];
+    	*l = codec_gain[0x1f - (l_val & 0x1f)];
+	*r = codec_gain[0x1f - (r_val & 0x1f)];
     }
 }
 

From 8485852b07cc7db364bc6efdb1b96345f867101a Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 27 Jul 2021 17:13:49 -0300
Subject: [PATCH 30/52] Add AC97 multi-codec support (unused) and fix gain
 calculation

---
 src/include/86box/snd_ac97.h |  7 ++--
 src/sound/snd_ac97_codec.c   | 74 ++++++++++++++++++++----------------
 src/sound/snd_ac97_via.c     |  1 +
 src/sound/snd_audiopci.c     |  3 +-
 4 files changed, 48 insertions(+), 37 deletions(-)

diff --git a/src/include/86box/snd_ac97.h b/src/include/86box/snd_ac97.h
index a72a874d9..8b5e89920 100644
--- a/src/include/86box/snd_ac97.h
+++ b/src/include/86box/snd_ac97.h
@@ -19,8 +19,8 @@
 
 
 typedef struct {
-    uint32_t	id;
-    uint8_t	regs[128];
+    uint32_t	vendor_id;
+    uint8_t	codec_id, regs[128];
 } ac97_codec_t;
 
 
@@ -40,7 +40,8 @@ extern void	ac97_via_remap_modem_codec(void *priv, uint16_t new_io_base, uint8_t
 
 #ifdef EMU_DEVICE_H
 extern ac97_codec_t	**ac97_codec, **ac97_modem_codec;
-extern int		ac97_codec_count, ac97_modem_codec_count;
+extern int		ac97_codec_count, ac97_modem_codec_count,
+			ac97_codec_id, ac97_modem_codec_id;
 
 extern const device_t	alc100_device;
 extern const device_t	cs4297_device;
diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index 5532a1441..133b9f0c5 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -55,16 +55,14 @@ ac97_codec_log(const char *fmt, ...)
 #endif
 
 static const int32_t codec_attn[] = {
-      25,   32,   41,   51,   65,   82,  103,  130,  164,  206,   260,   327,   412,   519,   653,   822,
-    1036, 1304, 1641, 2067, 2602, 3276, 4125, 5192, 6537, 8230, 10362, 13044, 16422, 20674, 26027, 32767
-};
-static const int32_t codec_gain[] = {
-    8545, 8552,  8561,  8571,  8585,  8602,  8623,  8650,  8684,  8726,  8780,  8847,  8932,  9039,  9173,  9342,
-    9556, 9824, 10161, 10587, 11122, 11796, 12645, 13712, 15057, 16750, 18882, 21564, 24942, 29194, 34547, 41287
+       25,    32,    41,    51,     65,     82,    103,    130,  164,  206,   260,   327,   412,   519,   653,   822,
+     1036,  1304,  1641,  2067,   2602,   3276,   4125,   5192, 6537, 8230, 10362, 13044, 16422, 20674, 26027, 32767,
+    41305, 52068, 65636, 82739, 104299,	131477, 165737, 208925
 };
 
 ac97_codec_t	**ac97_codec = NULL, **ac97_modem_codec = NULL;
-int		ac97_codec_count = 0, ac97_modem_codec_count = 0;
+int		ac97_codec_count = 0, ac97_modem_codec_count = 0,
+		ac97_codec_id = 0, ac97_modem_codec_id = 0;
 
 
 uint8_t
@@ -72,7 +70,7 @@ ac97_codec_read(ac97_codec_t *dev, uint8_t reg)
 {
     uint8_t ret = dev->regs[reg & 0x7f];
 
-    ac97_codec_log("AC97 Codec: read(%02X) = %02X\n", reg, ret);
+    ac97_codec_log("AC97 Codec %d: read(%02X) = %02X\n", dev->codec_id, reg, ret);
 
     return ret;
 }
@@ -81,7 +79,7 @@ ac97_codec_read(ac97_codec_t *dev, uint8_t reg)
 void
 ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 {
-    ac97_codec_log("AC97 Codec: write(%02X, %02X)\n", reg, val);
+    ac97_codec_log("AC97 Codec %d: write(%02X, %02X)\n", dev->codec_id, reg, val);
 
     reg &= 0x7f;
 
@@ -108,9 +106,16 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 	case 0x03: /* Master Volume MSB */
 	case 0x05: /* Aux Out Volume MSB */
 		val &= 0xbf;
+
+		/* Convert 6-bit level 1xxxxx to 011111 per specification. */
+		if (val & 0x20) {
+			val &= ~0x20;
+			val |= 0x1f;
+		}
 		break;
 
 	case 0x07: /* Mono Volume MSB */
+	case 0x0b: /* PC Beep Volume MSB */
 	case 0x20: /* General Purpose LSB */
 		val &= 0x80;
 		break;
@@ -118,12 +123,17 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 	case 0x02: /* Master Volume LSB */
 	case 0x04: /* Aux Out Volume LSB */
 	case 0x06: /* Mono Volume LSB */
-	case 0x0b: /* PC Beep Volume MSB */
 		val &= 0x3f;
+
+		/* Convert 6-bit level 1xxxxx to 011111 per specification. */
+		if (val & 0x20) {
+			val &= ~0x20;
+			val |= 0x1f;
+		}
 		break;
 
 	case 0x0a: /* PC Beep Volume LSB */
-		val &= 0xfe;
+		val &= 0x1e;
 		break;
 
 	case 0x0c: /* Phone Volume LSB */
@@ -173,7 +183,7 @@ ac97_codec_reset(void *priv)
 {
     ac97_codec_t *dev = (ac97_codec_t *) priv;
 
-    ac97_codec_log("AC97 Codec: reset()\n");
+    ac97_codec_log("AC97 Codec %d: reset()\n", dev->codec_id);
 
     memset(dev->regs, 0, sizeof(dev->regs));
 
@@ -183,11 +193,12 @@ ac97_codec_reset(void *priv)
     /* Flag codec as ready. */
     dev->regs[0x26] = 0x0f;
 
-    /* Set Vendor ID. */
-    dev->regs[0x7c] = dev->id >> 16;
-    dev->regs[0x7d] = dev->id >> 24;
-    dev->regs[0x7e] = dev->id;
-    dev->regs[0x7f] = dev->id >> 8;
+    /* Set Codec and Vendor IDs. */
+    dev->regs[0x29] = (dev->codec_id << 6) | 0x02;
+    dev->regs[0x7c] = dev->vendor_id >> 16;
+    dev->regs[0x7d] = dev->vendor_id >> 24;
+    dev->regs[0x7e] = dev->vendor_id;
+    dev->regs[0x7f] = dev->vendor_id >> 8;
 }
 
 
@@ -204,18 +215,14 @@ ac97_codec_getattn(void *priv, uint8_t reg, int *l, int *r)
 	return;
     }
 
-    if (reg < 0x10) { /* 6-bit volume */
-    	if (l_val & 0x20)
-    		*l = codec_attn[0];
-    	else
-    		*l = codec_attn[0x1f - (l_val & 0x1f)];
-    	if (r_val & 0x20)
-    		*r = codec_attn[0];
-    	else
-    		*r = codec_attn[0x1f - (r_val & 0x1f)];
+    l_val &= 0x1f;
+    r_val &= 0x1f;
+    if (reg < 0x10) { /* 5-bit level (converted from 6-bit on register write) */
+	*l = codec_attn[0x1f - l_val];
+	*r = codec_attn[0x1f - r_val];
     } else { /* 5-bit gain */
-    	*l = codec_gain[0x1f - (l_val & 0x1f)];
-	*r = codec_gain[0x1f - (r_val & 0x1f)];
+	*l = codec_attn[0x27 - l_val];
+	*r = codec_attn[0x27 - r_val];
     }
 }
 
@@ -226,19 +233,20 @@ ac97_codec_init(const device_t *info)
     ac97_codec_t *dev = malloc(sizeof(ac97_codec_t));
     memset(dev, 0, sizeof(ac97_codec_t));
 
-    dev->id = info->local;
-    ac97_codec_log("AC97 Codec: init(%c%c%c%02X)\n", (dev->id >> 24) & 0xff, (dev->id >> 16) & 0xff, (dev->id >> 8) & 0xff, dev->id & 0xff);
+    dev->vendor_id = info->local;
+    ac97_codec_log("AC97 Codec %d: init(%c%c%c%02X)\n", ac97_codec_id, (dev->vendor_id >> 24) & 0xff, (dev->vendor_id >> 16) & 0xff, (dev->vendor_id >> 8) & 0xff, dev->vendor_id & 0xff);
 
     /* Associate this codec to the current controller. */
     if (!ac97_codec || (ac97_codec_count <= 0)) {
-    	fatal("AC97 Codec: No controller to associate codec");
-    	return NULL;
+	fatal("AC97 Codec %d: No controller to associate codec\n", ac97_codec_id);
+	return NULL;
     }
     *ac97_codec = dev;
     if (--ac97_codec_count == 0)
 	ac97_codec = NULL;
     else
 	ac97_codec += sizeof(ac97_codec_t *);
+    dev->codec_id = ac97_codec_id++;
 
     return dev;
 }
@@ -249,7 +257,7 @@ ac97_codec_close(void *priv)
 {
     ac97_codec_t *dev = (ac97_codec_t *) priv;
 
-    ac97_codec_log("AC97 Codec: close()\n");
+    ac97_codec_log("AC97 Codec %d: close()\n", dev->codec_id);
 
     free(dev);
 }
diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index bc2ec8ee9..a83ddc17a 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -750,6 +750,7 @@ ac97_via_init(const device_t *info)
     ac97_codec = &dev->codec[0][0];
     ac97_modem_codec = &dev->codec[1][0];
     ac97_codec_count = ac97_modem_codec_count = sizeof(dev->codec[0]) / sizeof(dev->codec[0][0]);
+    ac97_codec_id = ac97_modem_codec_id = 0;
 
     /* Set up SGD channels. */
     for (uint8_t i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++) {
diff --git a/src/sound/snd_audiopci.c b/src/sound/snd_audiopci.c
index cd8288d4d..886ab4ff2 100644
--- a/src/sound/snd_audiopci.c
+++ b/src/sound/snd_audiopci.c
@@ -1338,7 +1338,8 @@ static void *es1371_init(const device_t *info)
 
 	ac97_codec = &es1371->codec;
 	ac97_codec_count = 1;
-	if (!info->local)
+	ac97_codec_id = 0;
+	if (!info->local) /* let the machine decide the codec on onboard implementations */
 		device_add(&cs4297a_device);
 
 	return es1371;

From 8cf651db5719f82495dfe28657268cee419525c5 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 27 Jul 2021 22:53:24 -0300
Subject: [PATCH 31/52] AC97 improvements, including variable sample rate
 support on VIA

---
 src/include/86box/snd_ac97.h |  1 +
 src/sound/snd_ac97_codec.c   | 75 +++++++++++++++++++++++++++++++++---
 src/sound/snd_ac97_via.c     | 64 ++++++++++++++++++++++--------
 3 files changed, 119 insertions(+), 21 deletions(-)

diff --git a/src/include/86box/snd_ac97.h b/src/include/86box/snd_ac97.h
index 8b5e89920..99601e2e7 100644
--- a/src/include/86box/snd_ac97.h
+++ b/src/include/86box/snd_ac97.h
@@ -28,6 +28,7 @@ extern uint8_t	ac97_codec_read(ac97_codec_t *dev, uint8_t reg);
 extern void	ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val);
 extern void	ac97_codec_reset(void *priv);
 extern void	ac97_codec_getattn(void *priv, uint8_t reg, int *l, int *r);
+extern uint32_t	ac97_codec_getrate(void *priv, uint8_t reg);
 
 extern void	ac97_via_set_slot(void *priv, int slot, int irq_pin);
 extern uint8_t	ac97_via_read_status(void *priv, uint8_t modem);
diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index 133b9f0c5..02ae9cbe9 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -79,6 +79,8 @@ ac97_codec_read(ac97_codec_t *dev, uint8_t reg)
 void
 ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 {
+    uint8_t i;
+
     ac97_codec_log("AC97 Codec %d: write(%02X, %02X)\n", dev->codec_id, reg, val);
 
     reg &= 0x7f;
@@ -86,7 +88,7 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
     switch (reg) {
 	case 0x00: case 0x01: /* Reset / ID code */
 		ac97_codec_reset(dev);
-		/* fall-through */
+		return;
 
 	case 0x08: case 0x09: /* Master Tone Control (optional) */
 	case 0x0d: /* Phone Volume MSB */
@@ -96,7 +98,8 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 	case 0x24: case 0x25: /* Audio Interrupt and Paging Mechanism (optional) */
 	case 0x26: /* Powerdown Ctrl/Stat LSB */
 	case 0x28: case 0x29: /* Extended Audio ID */
-	//case 0x2a ... 0x59: /* Linux tests for audio capability by writing to 38-39 */
+	case 0x2b: /* Extended Audio Status/Control MSB */
+	//case 0x36 ... 0x59: /* Linux tests for audio capability by writing to 38-39 */
 	case 0x5a ... 0x5f: /* Vendor Reserved */
 	//case 0x60 ... 0x6f:
 	case 0x70 ... 0x7f: /* Vendor Reserved */
@@ -107,7 +110,7 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 	case 0x05: /* Aux Out Volume MSB */
 		val &= 0xbf;
 
-		/* Convert 6-bit level 1xxxxx to 011111 per specification. */
+		/* Convert 6-bit level 1xxxxx to 011111. */
 		if (val & 0x20) {
 			val &= ~0x20;
 			val |= 0x1f;
@@ -125,7 +128,7 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 	case 0x06: /* Mono Volume LSB */
 		val &= 0x3f;
 
-		/* Convert 6-bit level 1xxxxx to 011111 per specification. */
+		/* Convert 6-bit level 1xxxxx to 011111. */
 		if (val & 0x20) {
 			val &= ~0x20;
 			val |= 0x1f;
@@ -172,6 +175,34 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 	case 0x21: /* General Purpose MSB */
 		val &= 0x83;
 		break;
+
+	case 0x2a: /* Extended Audio Status/Control LSB */
+		val &= 0x0b;
+
+		/* Reset DAC sample rates to 48 KHz if VRA is being cleared. */
+		if (!(val & 0x01)) {
+			for (i = 0x2c; i <= 0x30; i += 2)
+				*((uint16_t *) &dev->regs[i]) = 48000;
+		}
+
+		/* Reset ADC sample rates to 48 KHz if VRM is being cleared. */
+		if (!(val & 0x08)) {
+			for (i = 0x32; i <= 0x34; i += 2)
+				*((uint16_t *) &dev->regs[i]) = 48000;
+		}
+		break;
+
+	case 0x2c ... 0x31: /* DAC Rates */
+		/* Writable only if VRA is set. */
+		if (!(dev->regs[0x2a] & 0x01))
+			return;
+		break;
+
+	case 0x32 ... 0x35: /* ADC Rates */
+		/* Writable only if VRM is set. */
+		if (!(dev->regs[0x2a] & 0x08))
+			return;
+		break;
     }
 
     dev->regs[reg] = val;
@@ -182,17 +213,28 @@ void
 ac97_codec_reset(void *priv)
 {
     ac97_codec_t *dev = (ac97_codec_t *) priv;
+    uint8_t i;
 
     ac97_codec_log("AC97 Codec %d: reset()\n", dev->codec_id);
 
     memset(dev->regs, 0, sizeof(dev->regs));
 
-    /* Mute outputs by default. */
-    dev->regs[0x02] = dev->regs[0x04] = dev->regs[0x06] = 0x80;
+    /* Set default level and gain values. */
+    for (i = 0x02; i <= 0x18; i += 2) {
+	if (i == 0x08)
+		continue;
+	if (i >= 0x0c)
+		dev->regs[i] = 0x08;
+	dev->regs[i | 1] = (i >= 0x10) ? 0x88 : 0x80;
+    }
 
     /* Flag codec as ready. */
     dev->regs[0x26] = 0x0f;
 
+    /* Set up variable sample rate support. */
+    dev->regs[0x28] = 0x0b;
+    ac97_codec_write(dev, 0x2a, 0x00); /* reset DAC/ADC sample rates */
+
     /* Set Codec and Vendor IDs. */
     dev->regs[0x29] = (dev->codec_id << 6) | 0x02;
     dev->regs[0x7c] = dev->vendor_id >> 16;
@@ -227,6 +269,24 @@ ac97_codec_getattn(void *priv, uint8_t reg, int *l, int *r)
 }
 
 
+uint32_t
+ac97_codec_getrate(void *priv, uint8_t reg)
+{
+    ac97_codec_t *dev = (ac97_codec_t *) priv;
+
+    /* Get configured sample rate, which is always 48000 if VRA/VRM is not set. */
+    uint32_t ret = *((uint16_t *) &dev->regs[reg]);
+
+    /* If this is a DAC, double sample rate if DRA is set. */
+    if ((reg < 0x32) && (dev->regs[0x2a] & 0x02))
+	ret <<= 1;
+
+    ac97_codec_log("AC97 Codec %d: getrate(%02X) = %d\n", dev->codec_id, reg, ret);
+
+    return ret;
+}
+
+
 static void *
 ac97_codec_init(const device_t *info)
 {
@@ -248,6 +308,9 @@ ac97_codec_init(const device_t *info)
 	ac97_codec += sizeof(ac97_codec_t *);
     dev->codec_id = ac97_codec_id++;
 
+    /* Initialize codec registers. */
+    ac97_codec_reset(dev);
+
     return dev;
 }
 
diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index a83ddc17a..476d05474 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -44,7 +44,7 @@ typedef struct {
 
 typedef struct _ac97_via_ {
     uint16_t	audio_sgd_base, audio_codec_base, modem_sgd_base, modem_codec_base;
-    uint8_t	sgd_regs[256], pcm_enabled: 1, fm_enabled: 1;
+    uint8_t	sgd_regs[256], pcm_enabled: 1, fm_enabled: 1, vsr_enabled: 1;
     struct {
 	union {
 		uint8_t regs_codec[2][128];
@@ -85,7 +85,8 @@ ac97_via_log(const char *fmt, ...)
 
 
 static void	ac97_via_sgd_process(void *priv);
-static void	ac97_via_update_volumes(ac97_via_t *dev, ac97_codec_t *codec);
+static void	ac97_via_update_codec(ac97_via_t *dev, ac97_codec_t *codec);
+static void	ac97_via_speed_changed(void *priv);
 
 
 void
@@ -126,20 +127,28 @@ ac97_via_write_control(void *priv, uint8_t modem, uint8_t val)
 
     ac97_via_log("AC97 VIA %d: write_control(%02X)\n", modem, val);
 
+    if (!modem) {
+	/* Set the variable sample rate flag now, so that the upcoming
+	   update_codec can properly update the poller timer interval. */
+	dev->vsr_enabled = !!(val & 0x08);
+    }
+
     /* Reset and/or update volumes on all codecs. */
     for (i = 0; i <= 1; i++) {
-	if (dev->codec[modem][i]) {
-		/* Reset codec if requested. */
-		if (val & 0x40)
-			ac97_codec_reset(dev->codec[modem][i]);
+	if (!dev->codec[modem][i])
+		continue;
 
-		/* Update volumes. */
-		ac97_via_update_volumes(dev, dev->codec[modem][i]);
-	}
+	/* Reset codec if requested. */
+	if (!(val & 0x40))
+		ac97_codec_reset(dev->codec[modem][i]);
+
+	/* Update primary codec state. */
+	if (!modem && !i)
+		ac97_via_update_codec(dev, dev->codec[modem][i]);
     }
 
     if (!modem) {
-    	/* Start or stop PCM playback. */
+	/* Start or stop PCM playback. */
 	i = (val & 0xf4) == 0xc4;
 	if (i && !dev->pcm_enabled)
 		timer_advance_u64(&dev->timer_count, dev->timer_latch);
@@ -174,12 +183,14 @@ ac97_via_update_irqs(ac97_via_t *dev)
 
 
 static void
-ac97_via_update_volumes(ac97_via_t *dev, ac97_codec_t *codec) {
+ac97_via_update_codec(ac97_via_t *dev, ac97_codec_t *codec) {
+    /* Update volumes according to codec registers. */
     ac97_codec_getattn(codec, 0x02, &dev->master_vol_l, &dev->master_vol_r);
     ac97_codec_getattn(codec, 0x18, &dev->pcm_vol_l, &dev->pcm_vol_r);
     ac97_codec_getattn(codec, 0x12, &dev->cd_vol_l, &dev->cd_vol_r);
 
-    pclog("master %d %d\npcm %d %d\ncd %d %d\n", dev->master_vol_l, dev->master_vol_r, dev->pcm_vol_l, dev->pcm_vol_r, dev->cd_vol_l, dev->cd_vol_r);
+    /* Update sample rate according to codec registers and the variable sample rate bit. */
+    ac97_via_speed_changed(dev);
 }
 
 
@@ -377,8 +388,9 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 					val |= 1;
 					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x81]);
 
-					/* Update volumes. */
-					ac97_via_update_volumes(dev, codec);
+					/* Update primary codec state. */
+					if (!modem && !i)
+						ac97_via_update_codec(dev, codec);
 				}
 
 				/* Flag data/status/index for this codec as valid. */
@@ -729,11 +741,30 @@ ac97_via_get_buffer(int32_t *buffer, int len, void *priv)
 }
 
 
+static void
+via_ac97_filter_cd_audio(int channel, double *buffer, void *priv)
+{
+    ac97_via_t *dev = (ac97_via_t *) priv;
+    double c, volume = channel ? dev->cd_vol_r : dev->cd_vol_l;
+
+    c = ((*buffer) * volume) / 65536.0;
+    *buffer = c;
+}
+
+
 static void
 ac97_via_speed_changed(void *priv)
 {
     ac97_via_t *dev = (ac97_via_t *) priv;
-    dev->timer_latch = (uint64_t) ((double) TIMER_USEC * (1000000.0 / 48000.0));
+    double freq;
+
+    /* Get variable sample rate if enabled. */
+    if (dev->vsr_enabled && dev->codec[0][0])
+	freq = ac97_codec_getrate(dev->codec[0][0], 0x2c);
+    else
+	freq = 48000.0;
+
+    dev->timer_latch = (uint64_t) ((double) TIMER_USEC * (1000000.0 / freq));
     dev->timer_fifo_latch = (uint64_t) ((double) TIMER_USEC * 10.0);
 }
 
@@ -772,6 +803,9 @@ ac97_via_init(const device_t *info)
     /* Set up playback handler. */
     sound_add_handler(ac97_via_get_buffer, dev);
 
+    /* Set up CD audio filter. */
+    sound_set_cd_audio_filter(via_ac97_filter_cd_audio, dev);
+
     return dev;
 }
 

From 89d6a67e86d05c00dd245e4a07d6f104e727fd7a Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Thu, 29 Jul 2021 00:47:39 -0300
Subject: [PATCH 32/52] More AC97 work, including 48 KHz sample rate cap

---
 src/device/smbus_piix4.c   |  4 +--
 src/sound/snd_ac97_codec.c | 52 +++++++++++++++++++++-----------------
 src/sound/snd_ac97_via.c   | 50 +++++++++++++++++-------------------
 3 files changed, 54 insertions(+), 52 deletions(-)

diff --git a/src/device/smbus_piix4.c b/src/device/smbus_piix4.c
index 91ee5566e..271747d92 100644
--- a/src/device/smbus_piix4.c
+++ b/src/device/smbus_piix4.c
@@ -124,13 +124,13 @@ smbus_piix4_write(uint16_t addr, uint8_t val, void *priv)
 		if (val & 0x40) { /* dispatch command if START is set */
 			timer_bytes++; /* address */
 
-			smbus_addr = (dev->addr >> 1);
+			smbus_addr = dev->addr >> 1;
 			read = dev->addr & 0x01;
 
 			cmd = (dev->ctl >> 2) & 0xf;
 			smbus_piix4_log("SMBus PIIX4: addr=%02X read=%d protocol=%X cmd=%02X data0=%02X data1=%02X\n", smbus_addr, read, cmd, dev->cmd, dev->data0, dev->data1);
 
-			/* Raise DEV_ERR if no device is at this address, or if the device returned NAK when starting the transfer. */
+			/* Raise DEV_ERR if no device is at this address, or if the device returned NAK. */
 			if (!i2c_start(i2c_smbus, smbus_addr, read)) {
 				dev->next_stat = 0x04;
 				break;
diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index 02ae9cbe9..2ae310465 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -106,11 +106,17 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 		/* Read-only registers. */
 		return;
 
+	case 0x02: /* Master Volume LSB */
+	case 0x04: /* Aux Out Volume LSB */
+	case 0x06: /* Mono Volume LSB */
+		val &= 0x3f;
+		/* fall-through */
+
 	case 0x03: /* Master Volume MSB */
 	case 0x05: /* Aux Out Volume MSB */
 		val &= 0xbf;
 
-		/* Convert 6-bit level 1xxxxx to 011111. */
+		/* Limit level to a maximum of 011111. */
 		if (val & 0x20) {
 			val &= ~0x20;
 			val |= 0x1f;
@@ -123,18 +129,6 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 		val &= 0x80;
 		break;
 
-	case 0x02: /* Master Volume LSB */
-	case 0x04: /* Aux Out Volume LSB */
-	case 0x06: /* Mono Volume LSB */
-		val &= 0x3f;
-
-		/* Convert 6-bit level 1xxxxx to 011111. */
-		if (val & 0x20) {
-			val &= ~0x20;
-			val |= 0x1f;
-		}
-		break;
-
 	case 0x0a: /* PC Beep Volume LSB */
 		val &= 0x1e;
 		break;
@@ -177,9 +171,12 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 		break;
 
 	case 0x2a: /* Extended Audio Status/Control LSB */
+#ifdef AC97_CODEC_FULL_RATE_RANGE /* enable DRA (double rate) support */
 		val &= 0x0b;
-
-		/* Reset DAC sample rates to 48 KHz if VRA is being cleared. */
+#else
+		val &= 0x09;
+#endif
+		/* Reset DAC sample rates to 48 KHz (96 KHz with DRA) if VRA is being cleared. */
 		if (!(val & 0x01)) {
 			for (i = 0x2c; i <= 0x30; i += 2)
 				*((uint16_t *) &dev->regs[i]) = 48000;
@@ -192,16 +189,19 @@ ac97_codec_write(ac97_codec_t *dev, uint8_t reg, uint8_t val)
 		}
 		break;
 
-	case 0x2c ... 0x31: /* DAC Rates */
-		/* Writable only if VRA is set. */
-		if (!(dev->regs[0x2a] & 0x01))
+	case 0x2c ... 0x35: /* DAC/ADC Rates */
+		/* Writable only if VRA/VRM is set. */
+		i = (reg >= 0x32) ? 0x08 : 0x01;
+		if (!(dev->regs[0x2a] & i))
 			return;
-		break;
 
-	case 0x32 ... 0x35: /* ADC Rates */
-		/* Writable only if VRM is set. */
-		if (!(dev->regs[0x2a] & 0x08))
+#ifndef AC97_CODEC_FULL_RATE_RANGE
+		/* Limit to 48 KHz on MSB write. */
+		if ((reg & 1) && (((val << 8) | dev->regs[reg & 0x7e]) > 48000)) {
+			*((uint16_t *) &dev->regs[reg & 0x7e]) = 48000;
 			return;
+		}
+#endif
 		break;
     }
 
@@ -232,10 +232,14 @@ ac97_codec_reset(void *priv)
     dev->regs[0x26] = 0x0f;
 
     /* Set up variable sample rate support. */
+#ifdef AC97_CODEC_FULL_RATE_RANGE /* enable DRA (double rate) support */
     dev->regs[0x28] = 0x0b;
+#else
+    dev->regs[0x28] = 0x09;
+#endif
     ac97_codec_write(dev, 0x2a, 0x00); /* reset DAC/ADC sample rates */
 
-    /* Set Codec and Vendor IDs. */
+    /* Set codec and vendor IDs. */
     dev->regs[0x29] = (dev->codec_id << 6) | 0x02;
     dev->regs[0x7c] = dev->vendor_id >> 16;
     dev->regs[0x7d] = dev->vendor_id >> 24;
@@ -277,9 +281,11 @@ ac97_codec_getrate(void *priv, uint8_t reg)
     /* Get configured sample rate, which is always 48000 if VRA/VRM is not set. */
     uint32_t ret = *((uint16_t *) &dev->regs[reg]);
 
+#ifdef AC97_CODEC_FULL_RATE_RANGE
     /* If this is a DAC, double sample rate if DRA is set. */
     if ((reg < 0x32) && (dev->regs[0x2a] & 0x02))
 	ret <<= 1;
+#endif
 
     ac97_codec_log("AC97 Codec %d: getrate(%02X) = %d\n", dev->codec_id, reg, ret);
 
diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 476d05474..262872e5e 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -85,7 +85,7 @@ ac97_via_log(const char *fmt, ...)
 
 
 static void	ac97_via_sgd_process(void *priv);
-static void	ac97_via_update_codec(ac97_via_t *dev, ac97_codec_t *codec);
+static void	ac97_via_update_codec(ac97_via_t *dev);
 static void	ac97_via_speed_changed(void *priv);
 
 
@@ -127,27 +127,18 @@ ac97_via_write_control(void *priv, uint8_t modem, uint8_t val)
 
     ac97_via_log("AC97 VIA %d: write_control(%02X)\n", modem, val);
 
-    if (!modem) {
-	/* Set the variable sample rate flag now, so that the upcoming
-	   update_codec can properly update the poller timer interval. */
-	dev->vsr_enabled = !!(val & 0x08);
-    }
-
-    /* Reset and/or update volumes on all codecs. */
-    for (i = 0; i <= 1; i++) {
-	if (!dev->codec[modem][i])
-		continue;
-
-	/* Reset codec if requested. */
-	if (!(val & 0x40))
-		ac97_codec_reset(dev->codec[modem][i]);
-
-	/* Update primary codec state. */
-	if (!modem && !i)
-		ac97_via_update_codec(dev, dev->codec[modem][i]);
+    /* Reset codecs if requested. */
+    if (!(val & 0x40)) {
+	for (i = 0; i <= 1; i++) {
+		if (dev->codec[modem][i])
+			ac97_codec_reset(dev->codec[modem][i]);
+	}
     }
 
     if (!modem) {
+	/* Set the variable sample rate flag. */
+	dev->vsr_enabled = (val & 0xf8) == 0xc8;
+
 	/* Start or stop PCM playback. */
 	i = (val & 0xf4) == 0xc4;
 	if (i && !dev->pcm_enabled)
@@ -159,6 +150,10 @@ ac97_via_write_control(void *priv, uint8_t modem, uint8_t val)
 	if (i && !dev->fm_enabled)
 		timer_advance_u64(&dev->timer_count_fm, dev->timer_latch);
 	dev->fm_enabled = i;
+
+	/* Update primary audio codec state. */
+	if (dev->codec[0][0])
+		ac97_via_update_codec(dev);
     }
 }
 
@@ -167,12 +162,10 @@ static void
 ac97_via_update_irqs(ac97_via_t *dev)
 {
     /* Check interrupt flags in all SGDs. */
-    uint8_t i, sgd_id;
-    for (i = 0; i < (sizeof(dev->sgd) / sizeof(dev->sgd[0])); i++) {
-	sgd_id = i << 4;
+    for (uint8_t i = 0x00; i < ((sizeof(dev->sgd) / sizeof(dev->sgd[0])) << 4); i += 0x10) {
 	/* Stop immediately if any flag is set. Doing it this way optimizes
 	   rising edges for the playback SGD (0 - first to be checked). */
-	if (dev->sgd_regs[sgd_id] & (dev->sgd_regs[sgd_id | 0x2] & 0x03)) {
+	if (dev->sgd_regs[i] & (dev->sgd_regs[i | 0x2] & 0x03)) {
 		pci_set_irq(dev->slot, dev->irq_pin);
 		return;
 	}
@@ -183,13 +176,16 @@ ac97_via_update_irqs(ac97_via_t *dev)
 
 
 static void
-ac97_via_update_codec(ac97_via_t *dev, ac97_codec_t *codec) {
+ac97_via_update_codec(ac97_via_t *dev) {
+    /* Get primary audio codec. */
+    ac97_codec_t *codec = dev->codec[0][0];
+
     /* Update volumes according to codec registers. */
     ac97_codec_getattn(codec, 0x02, &dev->master_vol_l, &dev->master_vol_r);
     ac97_codec_getattn(codec, 0x18, &dev->pcm_vol_l, &dev->pcm_vol_r);
     ac97_codec_getattn(codec, 0x12, &dev->cd_vol_l, &dev->cd_vol_r);
 
-    /* Update sample rate according to codec registers and the variable sample rate bit. */
+    /* Update sample rate according to codec registers and the variable sample rate flag. */
     ac97_via_speed_changed(dev);
 }
 
@@ -388,9 +384,9 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 					val |= 1;
 					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x81]);
 
-					/* Update primary codec state. */
+					/* Update primary audio codec state if that codec was written to. */
 					if (!modem && !i)
-						ac97_via_update_codec(dev, codec);
+						ac97_via_update_codec(dev);
 				}
 
 				/* Flag data/status/index for this codec as valid. */

From 733af3b2fbe61ce41bb4c9bf5af61a1a4e61a961 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Thu, 29 Jul 2021 00:50:21 -0300
Subject: [PATCH 33/52] Remove extraneous comment

---
 src/config.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/config.c b/src/config.c
index cf66f160b..6aec4db72 100644
--- a/src/config.c
+++ b/src/config.c
@@ -689,7 +689,7 @@ load_machine(void)
     if (p) {
 	if (! strcmp(p, "enh_am486dx2")) /* migrate modified names */
 		cpu_f = cpu_get_family("am486dx2_slenh");
-	else if (! strcmp(p, "enh_am486dx4")) /* migrate modified names */
+	else if (! strcmp(p, "enh_am486dx4"))
 		cpu_f = cpu_get_family("am486dx4_slenh");
 	else
 		cpu_f = cpu_get_family(p);

From 8cf5e3d77f302504a2aa7716f79212f2b9a33aa4 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Thu, 29 Jul 2021 13:21:12 -0300
Subject: [PATCH 34/52] Update VIA AC97 codec write behavior to match hardware

---
 src/sound/snd_ac97_codec.c | 12 ++++++------
 src/sound/snd_ac97_via.c   | 29 +++++++++++++++--------------
 2 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index 2ae310465..9cd47ad90 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -25,17 +25,17 @@
 #include <86box/io.h>
 #include <86box/snd_ac97.h>
 
-#define AC97_CODEC_ID(f, s, t, dev)	((((f) & 0xff) << 24) | (((s) & 0xff) << 16) | (((t) & 0xff) << 8) | ((dev) & 0xff))
+#define AC97_VENDOR_ID(f, s, t, dev)	((((f) & 0xff) << 24) | (((s) & 0xff) << 16) | (((t) & 0xff) << 8) | ((dev) & 0xff))
 
 
 enum {
-    AC97_CODEC_ALC100 = AC97_CODEC_ID('A', 'L', 'C', 0x20),
-    AC97_CODEC_CS4297 = AC97_CODEC_ID('C', 'R', 'Y', 0x03),
-    AC97_CODEC_CS4297A = AC97_CODEC_ID('C', 'R', 'Y', 0x13),
-    AC97_CODEC_WM9701A = AC97_CODEC_ID('W', 'M', 'L', 0x00)
+    AC97_CODEC_ALC100 = AC97_VENDOR_ID('A', 'L', 'C', 0x20),
+    AC97_CODEC_CS4297 = AC97_VENDOR_ID('C', 'R', 'Y', 0x03),
+    AC97_CODEC_CS4297A = AC97_VENDOR_ID('C', 'R', 'Y', 0x13),
+    AC97_CODEC_WM9701A = AC97_VENDOR_ID('W', 'M', 'L', 0x00)
 };
 
-#define ENABLE_AC97_CODEC_LOG 1
+
 #ifdef ENABLE_AC97_CODEC_LOG
 int ac97_codec_do_log = ENABLE_AC97_CODEC_LOG;
 
diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 262872e5e..9d46dfccd 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -371,15 +371,22 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 			i = !!(dev->sgd_regs[0x83] & 0x40);
 			codec = dev->codec[modem][i];
 
-			/* Read from or write to codec. */
+			/* Keep value in register if this codec is not present. */
 			if (codec) {
+				/* Read from or write to codec. */
 				if (val & 0x80) {
-					val &= 0x7e;
-					dev->sgd_regs[0x80] = dev->codec_shadow[modem].regs_codec[i][val] = ac97_codec_read(codec, val);
-					val |= 1;
-					dev->sgd_regs[0x81] = dev->codec_shadow[modem].regs_codec[i][val] = ac97_codec_read(codec, val);
-				} else {
-					val &= 0x7e;
+					if (val & 1) { /* return 0x00 on unaligned reads */
+						dev->sgd_regs[0x80] = dev->sgd_regs[0x81] = 0x00;
+					} else {
+						dev->sgd_regs[0x80] = dev->codec_shadow[modem].regs_codec[i][val] = ac97_codec_read(codec, val);
+						val |= 1;
+						dev->sgd_regs[0x81] = dev->codec_shadow[modem].regs_codec[i][val] = ac97_codec_read(codec, val);
+					}
+
+					/* Flag data/status/index for this codec as valid. */
+					if (val & 0x80)
+						dev->sgd_regs[0x83] |= 0x02 << (i << 1);
+				} else if (!(val & 1)) { /* do nothing on unaligned writes */
 					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x80]);
 					val |= 1;
 					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x81]);
@@ -388,12 +395,6 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 					if (!modem && !i)
 						ac97_via_update_codec(dev);
 				}
-
-				/* Flag data/status/index for this codec as valid. */
-				dev->sgd_regs[0x83] |= 0x02 << (i * 2);
-			} else if (val & 0x80) {
-				/* Unknown behavior when reading from an absent codec. */
-				dev->sgd_regs[0x80] = dev->sgd_regs[0x81] = 0xff;
 			}
 			break;
 
@@ -402,7 +403,7 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 #if 0 /* race condition with Linux accessing a register and clearing status bits on the same dword write */
 			val = (dev->sgd_regs[addr] & ~(val & 0x0a)) | (val & 0xc0);
 #else
-			val = dev->sgd_regs[addr] | 0x0a | (val & 0xc0);
+			val = dev->sgd_regs[addr] | (val & 0xc0);
 #endif
 			break;
 	}

From c5c6cb715c76db99def5fe5a7a20d2739946c078 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Thu, 29 Jul 2021 13:23:18 -0300
Subject: [PATCH 35/52] Fix overwritten register index value oversight

---
 src/sound/snd_ac97_via.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 9d46dfccd..1349d0849 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -378,18 +378,16 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 					if (val & 1) { /* return 0x00 on unaligned reads */
 						dev->sgd_regs[0x80] = dev->sgd_regs[0x81] = 0x00;
 					} else {
-						dev->sgd_regs[0x80] = dev->codec_shadow[modem].regs_codec[i][val] = ac97_codec_read(codec, val);
-						val |= 1;
-						dev->sgd_regs[0x81] = dev->codec_shadow[modem].regs_codec[i][val] = ac97_codec_read(codec, val);
+						dev->sgd_regs[0x80] = dev->codec_shadow[modem].regs_codec[i][val]     = ac97_codec_read(codec, val);
+						dev->sgd_regs[0x81] = dev->codec_shadow[modem].regs_codec[i][val | 1] = ac97_codec_read(codec, val | 1);
 					}
 
 					/* Flag data/status/index for this codec as valid. */
 					if (val & 0x80)
 						dev->sgd_regs[0x83] |= 0x02 << (i << 1);
 				} else if (!(val & 1)) { /* do nothing on unaligned writes */
-					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x80]);
-					val |= 1;
-					ac97_codec_write(codec, val, dev->codec_shadow[modem].regs_codec[i][val] = dev->sgd_regs[0x81]);
+					ac97_codec_write(codec, val,     dev->codec_shadow[modem].regs_codec[i][val]     = dev->sgd_regs[0x80]);
+					ac97_codec_write(codec, val | 1, dev->codec_shadow[modem].regs_codec[i][val | 1] = dev->sgd_regs[0x81]);
 
 					/* Update primary audio codec state if that codec was written to. */
 					if (!modem && !i)

From d61e3b1e94096b418e16dff9704f4d1c1bf375d8 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Fri, 30 Jul 2021 00:17:49 -0300
Subject: [PATCH 36/52] Add AMR bus for optional AC97 audio on CUV4X-LS

---
 src/device.c                |  4 ++++
 src/include/86box/machine.h |  1 +
 src/machine/machine_table.c | 16 ++++++++--------
 src/sound/sound.c           |  2 ++
 4 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/src/device.c b/src/device.c
index 439f558a1..265fdf215 100644
--- a/src/device.c
+++ b/src/device.c
@@ -394,6 +394,8 @@ device_get_name(const device_t *d, int bus, char *name)
 		sbus = "PCI";
 	else if (d->flags & DEVICE_AGP)
 		sbus = "AGP";
+	else if (d->flags & DEVICE_AC97)
+		sbus = "AMR";
 
 	if (sbus != NULL) {
 		/* First concatenate [<Bus>] before the device's name. */
@@ -666,6 +668,8 @@ device_is_valid(const device_t *device, int mflags)
 
     if ((device->flags & DEVICE_PS2) && !(mflags & MACHINE_BUS_PS2)) return(0);
 
+    if ((device->flags & DEVICE_AC97) && !(mflags & MACHINE_BUS_AC97)) return(0);
+
     return(1);
 }
 
diff --git a/src/include/86box/machine.h b/src/include/86box/machine.h
index 2996133dc..fd01e37eb 100644
--- a/src/include/86box/machine.h
+++ b/src/include/86box/machine.h
@@ -37,6 +37,7 @@
 #define MACHINE_BUS_PCI		0x00000200	/* sys has PCI bus */
 #define MACHINE_BUS_PCMCIA	0x00000400	/* sys has PCMCIA bus */
 #define MACHINE_BUS_AGP		0x00000800	/* sys has AGP bus */
+#define MACHINE_BUS_AC97	0x00080000	/* sys has AC97 bus (ACR/AMR/CNR slot) */
 /* Combined flags. */
 #define MACHINE_PC		0x00000004	/* sys is PC/XT-compatible (ISA) */
 #define MACHINE_AT		0x0000000C	/* sys is AT-compatible (ISA + ISA16) */
diff --git a/src/machine/machine_table.c b/src/machine/machine_table.c
index 99165c58e..f8a4f3bb7 100644
--- a/src/machine/machine_table.c
+++ b/src/machine/machine_table.c
@@ -190,7 +190,7 @@ const machine_t machines[] = {
     /* 386DX machines which utilize the MCA bus */
     { "[MCA] IBM PS/2 model 70 (type 3)",	"ibmps2_m70_type3",	MACHINE_TYPE_386DX,		CPU_PKG_386DX | CPU_PKG_486BL, 0, 0, 0, 0, 0, 0, 0,								MACHINE_MCA | MACHINE_BUS_PS2 | MACHINE_VIDEO,					 2048, 16384, 2048,  63,      machine_ps2_model_70_type3_init, NULL			},
     { "[MCA] IBM PS/2 model 80",		"ibmps2_m80",		MACHINE_TYPE_386DX,		CPU_PKG_386DX | CPU_PKG_486BL, 0, 0, 0, 0, 0, 0, 0,								MACHINE_MCA | MACHINE_BUS_PS2 | MACHINE_VIDEO,					 1024, 12288, 1024,  63,	    machine_ps2_model_80_init, NULL			},
-    { "[MCA] IBM PS/2 model 80 (type 3)",	"ibmps2_m80_type3",		MACHINE_TYPE_386DX,		CPU_PKG_386DX | CPU_PKG_486BL, 0, 0, 0, 0, 0, 0, 0,								MACHINE_MCA | MACHINE_BUS_PS2 | MACHINE_VIDEO,					 2048, 12288, 2048,  63,	    machine_ps2_model_80_axx_init, NULL			},
+    { "[MCA] IBM PS/2 model 80 (type 3)",	"ibmps2_m80_type3",	MACHINE_TYPE_386DX,		CPU_PKG_386DX | CPU_PKG_486BL, 0, 0, 0, 0, 0, 0, 0,								MACHINE_MCA | MACHINE_BUS_PS2 | MACHINE_VIDEO,					 2048, 12288, 2048,  63,	machine_ps2_model_80_axx_init, NULL			},
 
     /* 386DX/486 machines */
     { "[OPTi 495] Award 486 clone",		"award486",		MACHINE_TYPE_386DX_486,		CPU_PKG_386DX | CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,								MACHINE_VLB | MACHINE_IDE,							 1024, 32768, 1024, 127,	      machine_at_opti495_init, NULL			},
@@ -200,11 +200,11 @@ const machine_t machines[] = {
     /* 486 machines - Socket 1 */
     { "[ALi M1429] Olystar LIL1429",		"ali1429",		MACHINE_TYPE_486,		CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,										MACHINE_VLB | MACHINE_IDE,							 1024, 32768, 1024, 127,	      machine_at_ali1429_init, NULL			},
     { "[CS4031] AMI 486 CS4031",		"cs4031",		MACHINE_TYPE_486,		CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,										MACHINE_VLB,									 1024, 65536, 1024, 127,	       machine_at_cs4031_init, NULL			},
-    { "[ETEQ ET6000] Olivetti PCS-46C",		"pcs46c",		MACHINE_TYPE_486,		CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,										MACHINE_VLB | MACHINE_IDE | MACHINE_VIDEO,							 4096, 32768, 4096, 127,	      machine_at_pcs46c_init, at_pcs46c_get_device			},
+    { "[ETEQ ET6000] Olivetti PCS-46C",		"pcs46c",		MACHINE_TYPE_486,		CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,										MACHINE_VLB | MACHINE_IDE | MACHINE_VIDEO,					 4096, 32768, 4096, 127,	       machine_at_pcs46c_init, at_pcs46c_get_device	},
     { "[OPTi 895] Mylex MVI486",		"mvi486",		MACHINE_TYPE_486,		CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,										MACHINE_VLB | MACHINE_IDE_DUAL,							 1024, 65536, 1024, 127,	       machine_at_mvi486_init, NULL			},
     { "[VIA VT82C495] FIC 486-VC-HD",		"486vchd",		MACHINE_TYPE_486,		CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,										MACHINE_AT,									 1024, 64512, 1024, 127,	      machine_at_486vchd_init, NULL			},
     { "[VLSI 82C480] HP Vectra 486VL",		"vect486vl",		MACHINE_TYPE_486,		CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,										MACHINE_AT | MACHINE_BUS_PS2 | MACHINE_IDE | MACHINE_VIDEO,			 2048, 32768, 2048, 127,	    machine_at_vect486vl_init, at_vect486vl_get_device	},
-    { "[VLSI 82C481] Siemens Nixdorf D824",		"d824",		MACHINE_TYPE_486,		CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,										MACHINE_AT | MACHINE_BUS_PS2 | MACHINE_IDE | MACHINE_VIDEO,			 2048, 32768, 2048, 127,	    machine_at_d824_init, at_d824_get_device	},
+    { "[VLSI 82C481] Siemens Nixdorf D824",	"d824",			MACHINE_TYPE_486,		CPU_PKG_SOCKET1, 0, 0, 0, 0, 0, 0, 0,										MACHINE_AT | MACHINE_BUS_PS2 | MACHINE_IDE | MACHINE_VIDEO,			 2048, 32768, 2048, 127,		 machine_at_d824_init, at_d824_get_device	},
 
     /* 486 machines - Socket 3 */
     /* 486 machines with just the ISA slot */
@@ -295,7 +295,7 @@ const machine_t machines[] = {
     { "[SiS 85C50x] BCM SQ-588",		"sq588",		MACHINE_TYPE_SOCKET5,		CPU_PKG_SOCKET5_7, CPU_BLOCK(CPU_PENTIUMMMX), 50000000, 66666667, 3520, 3520, 1.5, 1.5,				MACHINE_PCI | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,				 8192, 131072, 8192, 127,		machine_at_sq588_init, NULL			},
 
     /* UMC 889x */
-    { "[UMC 889x] Shuttle HOT-539",		"hot539",		MACHINE_TYPE_SOCKET5,		CPU_PKG_SOCKET5_7, CPU_BLOCK(CPU_K5, CPU_5K86), 40000000, 66666667, 3380, 3600, 1.5, 2.0,			MACHINE_PCI | MACHINE_IDE_DUAL,				 8192, 262144, 8192, 127,	       machine_at_hot539_init, NULL			},
+    { "[UMC 889x] Shuttle HOT-539",		"hot539",		MACHINE_TYPE_SOCKET5,		CPU_PKG_SOCKET5_7, CPU_BLOCK(CPU_K5, CPU_5K86), 40000000, 66666667, 3380, 3600, 1.5, 2.0,			MACHINE_PCI | MACHINE_IDE_DUAL,							 8192, 262144, 8192, 127,	       machine_at_hot539_init, NULL			},
 
     /* Socket 7 (Single Voltage) machines */
     /* 430FX */
@@ -318,7 +318,7 @@ const machine_t machines[] = {
     { "[i430VX] Gateway 2000 Tigereye",		"gw2kte",		MACHINE_TYPE_SOCKET7_3V,	CPU_PKG_SOCKET5_7, 0, 50000000, 66666667, 3380, 3520, 1.5, 3.0,							MACHINE_PCI | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,		 		 8192, 131072, 8192, 127,	       machine_at_gw2kte_init, NULL			},
 
     /* SiS 5511 */
-    { "[SiS 5511] AOpen AP5S",		"ap5s",		MACHINE_TYPE_SOCKET7_3V,	CPU_PKG_SOCKET5_7, 0, 50000000, 66666667, 3380, 3520, 1.5, 3.0,							MACHINE_PCI | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,		 		 8192, 524288, 8192, 127,	       machine_at_ap5s_init, NULL			},
+    { "[SiS 5511] AOpen AP5S",			"ap5s",			MACHINE_TYPE_SOCKET7_3V,	CPU_PKG_SOCKET5_7, 0, 50000000, 66666667, 3380, 3520, 1.5, 3.0,							MACHINE_PCI | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,		 		 8192, 524288, 8192, 127,		 machine_at_ap5s_init, NULL			},
 
     /* Socket 7 (Dual Voltage) machines */
     /* 430HX */
@@ -363,8 +363,8 @@ const machine_t machines[] = {
     { "[SiS 5571] MSI MS-5146",			"ms5146",		MACHINE_TYPE_SOCKET7,		CPU_PKG_SOCKET5_7, 0, 50000000, 66666667, 2500, 3520, 1.5, 3.0,							MACHINE_PCI | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,		  		 8192, 262144, 8192, 127,	       machine_at_ms5146_init, NULL			},
 
     /* SiS 5598 */
-    { "[SiS 5598] ASUS SP97-XV",		"sp97xv",		MACHINE_TYPE_SOCKET7,		CPU_PKG_SOCKET5_7, 0, 60000000, 66666667, 2100, 3200, 1.5, 2.5,							MACHINE_PCI | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,				 8192, 262144, 8192, 255,	     machine_at_sp97xv_init, NULL			},
-    { "[SiS 5598] PC Chips M571",		"m571",		MACHINE_TYPE_SOCKET7,		CPU_PKG_SOCKET5_7, 0, 50000000, 75000000, 2500, 3500, 1.5, 3.5,							MACHINE_PCI | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,				 8192, 262144, 8192, 255,	     machine_at_m571_init, NULL			},
+    { "[SiS 5598] ASUS SP97-XV",		"sp97xv",		MACHINE_TYPE_SOCKET7,		CPU_PKG_SOCKET5_7, 0, 60000000, 66666667, 2100, 3200, 1.5, 2.5,							MACHINE_PCI | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,				 8192, 262144, 8192, 255,	       machine_at_sp97xv_init, NULL			},
+    { "[SiS 5598] PC Chips M571",		"m571",			MACHINE_TYPE_SOCKET7,		CPU_PKG_SOCKET5_7, 0, 50000000, 75000000, 2500, 3500, 1.5, 3.5,							MACHINE_PCI | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,				 8192, 262144, 8192, 255,		 machine_at_m571_init, NULL			},
 
     /* ALi ALADDiN IV */
 #if defined(DEV_BRANCH) && defined(USE_M154X)
@@ -460,7 +460,7 @@ const machine_t machines[] = {
     { "[VIA Apollo Pro] PC Partner APAS3",	"apas3",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 100000000, 1800, 3500, 1.5, 8.0,						MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,	  			 8192, 786432, 8192, 255,		machine_at_apas3_init, NULL			},
     { "[VIA Apollo Pro133] ECS P6BAP",		"p6bap",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, 1.5, 8.0,						MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,	  			 8192,1572864, 8192, 255,		machine_at_p6bap_init, NULL			},
     { "[VIA Apollo Pro133A] AEWIN WCF-681",	"wcf681",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 133333333, 1300, 3500, 1.5, 8.0, /* limits assumed */				MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,	  			 8192,1048576, 8192, 255,	       machine_at_wcf681_init, NULL			},
-    { "[VIA Apollo Pro133A] ASUS CUV4X-LS",	"cuv4xls",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, 1.5, 8.0,						(MACHINE_AGP & ~MACHINE_AT) | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,		16384,1572864, 8192, 255,	      machine_at_cuv4xls_init, NULL			},
+    { "[VIA Apollo Pro133A] ASUS CUV4X-LS",	"cuv4xls",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, 1.5, 8.0,						(MACHINE_AGP & ~MACHINE_AT) | MACHINE_BUS_PS2 | MACHINE_BUS_AC97 | MACHINE_IDE_DUAL,16384,1572864, 8192, 255,	      machine_at_cuv4xls_init, NULL			},
     { "[VIA Apollo Pro133A] Acorp 6VIA90AP",	"6via90ap",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, MACHINE_MULTIPLIER_FIXED,				MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL | MACHINE_GAMEPORT,		 8192,1572864, 8192, 255,	     machine_at_6via90ap_init, NULL			},
     { "[VIA Apollo ProMedia] Jetway 603TCF",	"603tcf",		MACHINE_TYPE_SOCKET370,		CPU_PKG_SOCKET370, 0, 66666667, 150000000, 1300, 3500, 1.5, 8.0,						MACHINE_AGP | MACHINE_BUS_PS2 | MACHINE_IDE_DUAL,	  			 8192,1048576, 8192, 255,	       machine_at_603tcf_init, NULL			},
 
diff --git a/src/sound/sound.c b/src/sound/sound.c
index cddd83359..fa5d180ac 100644
--- a/src/sound/sound.c
+++ b/src/sound/sound.c
@@ -37,6 +37,7 @@
 #include <86box/snd_mpu401.h>
 #include <86box/snd_sb_dsp.h>
 #include <86box/snd_azt2316a.h>
+#include <86box/snd_ac97.h>
 #include <86box/filters.h>
 
 
@@ -109,6 +110,7 @@ static const SOUND_CARD sound_cards[] =
     { "sbmcv",		&sb_mcv_device			},
     { "sbpromcv",	&sb_pro_mcv_device		},
     { "es1371",		&es1371_device			},
+    { "cs4297a",	&cs4297a_device			},
     { "",		NULL				}
 };
 

From 720375bfd4052697b4eefc3302f1a8e44fb80ef3 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Mon, 2 Aug 2021 16:15:04 -0300
Subject: [PATCH 37/52] VIA AC97: workaround for V7.00b WDM driver hangs, and
 fix delayed starts caused by the SGD timer

---
 src/sound/snd_ac97_via.c | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 1349d0849..3d9956ae7 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -37,7 +37,7 @@ typedef struct {
 
     uint32_t	entry_ptr, sample_ptr, fifo_pos, fifo_end;
     int32_t	sample_count;
-    uint8_t	entry_flags, fifo[32], restart;
+    uint8_t	entry_flags, fifo[32], restart, status_shadow;
 
     pc_timer_t	timer;
 } ac97_via_sgd_t;
@@ -57,7 +57,7 @@ typedef struct _ac97_via_ {
     ac97_via_sgd_t sgd[6];
 
     pc_timer_t	timer_count, timer_count_fm;
-    uint64_t	timer_latch, timer_fifo_latch;
+    uint64_t	timer_latch;
     int16_t	out_l, out_r, fm_out_l, fm_out_r;
     int		master_vol_l, master_vol_r, pcm_vol_l, pcm_vol_r, cd_vol_l, cd_vol_r;
     int32_t	buffer[SOUNDBUFLEN * 2], fm_buffer[SOUNDBUFLEN * 2];
@@ -166,11 +166,13 @@ ac97_via_update_irqs(ac97_via_t *dev)
 	/* Stop immediately if any flag is set. Doing it this way optimizes
 	   rising edges for the playback SGD (0 - first to be checked). */
 	if (dev->sgd_regs[i] & (dev->sgd_regs[i | 0x2] & 0x03)) {
+		pclog("irq set\n");
 		pci_set_irq(dev->slot, dev->irq_pin);
 		return;
 	}
     }
 
+    pclog("irq cleared\n");
     pci_clear_irq(dev->slot, dev->irq_pin);
 }
 
@@ -203,6 +205,10 @@ ac97_via_sgd_read(uint16_t addr, void *priv)
     if (!(addr & 0x80)) {
 	/* Process SGD channel registers. */
 	switch (addr & 0xf) {
+		case 0x0:
+			ret = dev->sgd[addr >> 4].status_shadow;
+			break;
+
 		case 0x4:
 			ret = dev->sgd[addr >> 4].entry_ptr;
 			break;
@@ -235,6 +241,9 @@ ac97_via_sgd_read(uint16_t addr, void *priv)
 			ret = dev->sgd_regs[addr];
 			break;
 	}
+
+	/* Reset SGD status shadow register. See comment on SGD register 0x0 write for more information. */
+	dev->sgd[addr >> 4].status_shadow = dev->sgd_regs[addr & 0xf0];
     } else {
 	/* Process regular registers. */
 	switch (addr) {
@@ -312,6 +321,11 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 			/* Update status interrupts. */
 			ac97_via_update_irqs(dev);
 
+			/* Work around a race condition with the V7.00b WDM driver expecting SGD Active to
+			   not clear immediately. It reads this register next, so set up a shadow register
+			   to ensure SGD Active is set for that specific read (but not subsequent ones). */
+			dev->sgd[addr >> 4].status_shadow = dev->sgd_regs[addr] | 0x80;
+
 			return;
 
 		case 0x1:
@@ -394,6 +408,7 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 						ac97_via_update_codec(dev);
 				}
 			}
+
 			break;
 
 		case 0x83:
@@ -536,7 +551,7 @@ ac97_via_sgd_process(void *priv)
 	return;
 
     /* Schedule next run. */
-    timer_advance_u64(&sgd->timer, dev->timer_fifo_latch);
+    timer_on_auto(&sgd->timer, 10.0);
 
     /* Process SGD if it's active, and the FIFO has room or is disabled. */
     if ((sgd_status == 0x80) && (sgd->always_run || ((sgd->fifo_end - sgd->fifo_pos) <= (sizeof(sgd->fifo) - 4)))) {
@@ -585,13 +600,15 @@ ac97_via_sgd_process(void *priv)
 
 		if (sgd->entry_flags & 0x20) {
 			ac97_via_log(" with STOP");
+
+			/* Raise STOP to pause SGD. */
 			dev->sgd_regs[sgd->id] |= 0x04;
 		}
 
 		if (sgd->entry_flags & 0x40) {
 			ac97_via_log(" with FLAG");
 
-			/* Raise FLAG while also pausing SGD. */
+			/* Raise FLAG and STOP. */
 			dev->sgd_regs[sgd->id] |= 0x05;
 
 #ifdef ENABLE_AC97_VIA_LOG
@@ -760,7 +777,6 @@ ac97_via_speed_changed(void *priv)
 	freq = 48000.0;
 
     dev->timer_latch = (uint64_t) ((double) TIMER_USEC * (1000000.0 / freq));
-    dev->timer_fifo_latch = (uint64_t) ((double) TIMER_USEC * 10.0);
 }
 
 

From 413c4562b496b659b34f8983877e878c0030b55a Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Mon, 2 Aug 2021 16:18:21 -0300
Subject: [PATCH 38/52] Add AD1881 codec for the WIP branch's Gigabyte
 GA-6VX-4X

---
 src/include/86box/snd_ac97.h |  1 +
 src/sound/snd_ac97_codec.c   | 13 +++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/src/include/86box/snd_ac97.h b/src/include/86box/snd_ac97.h
index 99601e2e7..08f5747f6 100644
--- a/src/include/86box/snd_ac97.h
+++ b/src/include/86box/snd_ac97.h
@@ -44,6 +44,7 @@ extern ac97_codec_t	**ac97_codec, **ac97_modem_codec;
 extern int		ac97_codec_count, ac97_modem_codec_count,
 			ac97_codec_id, ac97_modem_codec_id;
 
+extern const device_t	ad1881_device;
 extern const device_t	alc100_device;
 extern const device_t	cs4297_device;
 extern const device_t	cs4297a_device;
diff --git a/src/sound/snd_ac97_codec.c b/src/sound/snd_ac97_codec.c
index 9cd47ad90..d9dd75d76 100644
--- a/src/sound/snd_ac97_codec.c
+++ b/src/sound/snd_ac97_codec.c
@@ -29,6 +29,7 @@
 
 
 enum {
+    AC97_CODEC_AD1881 = AC97_VENDOR_ID('A', 'D', 'S', 0x40),
     AC97_CODEC_ALC100 = AC97_VENDOR_ID('A', 'L', 'C', 0x20),
     AC97_CODEC_CS4297 = AC97_VENDOR_ID('C', 'R', 'Y', 0x03),
     AC97_CODEC_CS4297A = AC97_VENDOR_ID('C', 'R', 'Y', 0x13),
@@ -332,6 +333,18 @@ ac97_codec_close(void *priv)
 }
 
 
+const device_t ad1881_device =
+{
+    "Analog Devices AD1881",
+    DEVICE_AC97,
+    AC97_CODEC_AD1881,
+    ac97_codec_init, ac97_codec_close, ac97_codec_reset,
+    { NULL },
+    NULL,
+    NULL,
+    NULL
+};
+
 const device_t alc100_device =
 {
     "Avance Logic ALC100",

From 1d57246ee84d739efb57cf9aa68255b43f42947d Mon Sep 17 00:00:00 2001
From: Ompronce <88358700+Ompronce@users.noreply.github.com>
Date: Tue, 3 Aug 2021 02:46:09 -0400
Subject: [PATCH 39/52] Added correct AWE64 Gold RAM amounts

Corrected AWE64 Gold RAM amounts based on formulas seen here - https://www.vogons.org/viewtopic.php?p=988235#p988235
---
 src/sound/snd_sb.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/src/sound/snd_sb.c b/src/sound/snd_sb.c
index 3d8e51806..f7914a46d 100644
--- a/src/sound/snd_sb.c
+++ b/src/sound/snd_sb.c
@@ -2560,21 +2560,18 @@ static const device_config_t sb_awe64_gold_config[] =
         {
                 "onboard_ram", "Onboard RAM", CONFIG_SELECTION, "", 4096, "", { 0 },
                 {
-                        {
-                                "None", 0
-                        },
-                        {
-                                "512 KB", 512
-                        },
-                        {
-                                "2 MB", 2048
-                        },
                         {
                                 "4 MB", 4096
                         },
                         {
                                 "8 MB", 8192
                         },
+                        {
+                                "12 MB", 12288
+                        },
+                        {
+                                "16 MB", 16384
+                        },
                         {
                                 "28 MB", 28*1024
                         },

From d2d5906e2fb9accdd08bf55569a8d97437ae7a40 Mon Sep 17 00:00:00 2001
From: Ompronce <88358700+Ompronce@users.noreply.github.com>
Date: Tue, 3 Aug 2021 02:57:54 -0400
Subject: [PATCH 40/52] Added correct SB 32 PnP RAM amounts

Corrected Sound Blaster 32 PnP RAM amounts based on formulas seen here - https://www.vogons.org/viewtopic.php?p=988235#p988235
---
 src/sound/snd_sb.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/sound/snd_sb.c b/src/sound/snd_sb.c
index f7914a46d..7361d90cd 100644
--- a/src/sound/snd_sb.c
+++ b/src/sound/snd_sb.c
@@ -2341,9 +2341,6 @@ static const device_config_t sb_32_pnp_config[] =
                         {
                                 "None", 0
                         },
-                        {
-                                "512 KB", 512
-                        },
                         {
                                 "2 MB", 2048
                         },

From a25eeed22850fc1ffcec8c8b95b4030be535b3a2 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 13:03:33 -0300
Subject: [PATCH 41/52] Improve VIA 686 Super I/O and hardware monitor to match
 probed hardware behavior

---
 src/device/hwm_vt82c686.c |  42 +++++++++++-----
 src/sio/sio_vt82c686.c    | 102 +++++++++++++++++++++++++++-----------
 2 files changed, 104 insertions(+), 40 deletions(-)

diff --git a/src/device/hwm_vt82c686.c b/src/device/hwm_vt82c686.c
index 70a01a6ac..1790cd483 100644
--- a/src/device/hwm_vt82c686.c
+++ b/src/device/hwm_vt82c686.c
@@ -29,18 +29,17 @@
 
 #define CLAMP(a, min, max)		(((a) < (min)) ? (min) : (((a) > (max)) ? (max) : (a)))
 #define VT82C686_RPM_TO_REG(r, d)	((r) ? CLAMP(1350000 / (r * d), 1, 255) : 0)
-/* Temperature/voltage formulas and factors derived from Linux's via686a.c driver */
+/* Temperature/voltage formulas and factors derived from Linux's via686a.c driver. */
 #define VT82C686_TEMP_TO_REG(t)		(-1.160370e-10*(t*t*t*t*t*t) + 3.193693e-08*(t*t*t*t*t) - 1.464447e-06*(t*t*t*t) - 2.525453e-04*(t*t*t) + 1.424593e-02*(t*t) + 2.148941e+00*t + 7.275808e+01)
 #define VT82C686_VOLTAGE_TO_REG(v, f)	CLAMP((((v) * (2.628 / (f))) - 120.5) / 25, 0, 255)
 
 
 typedef struct {
     hwm_values_t *values;
-    device_t     *lm75[2];
 
     uint8_t	enable;
     uint16_t	io_base;
-    uint8_t	regs[80];
+    uint8_t	regs[128];
 } vt82c686_t;
 
 
@@ -59,6 +58,11 @@ vt82c686_read(uint16_t addr, void *priv)
     addr -= dev->io_base;
 
     switch (addr) {
+	case 0x00 ... 0x0f: case 0x50 ... 0x7f: /* undefined registers */
+		/* Real 686B returns the contents of 0x40. */
+		ret = dev->regs[0x40];
+		break;
+
 	case 0x1f: case 0x20: case 0x21: /* temperatures */
 		ret = VT82C686_TEMP_TO_REG(dev->values->temperatures[(addr == 0x1f) ? 2 : (addr & 1)]);
 		break;
@@ -84,14 +88,26 @@ static void
 vt82c686_write(uint16_t port, uint8_t val, void *priv)
 {
     vt82c686_t *dev = (vt82c686_t *) priv;
-    uint8_t reg = port - dev->io_base;
+    uint8_t reg = port & 0x7f;
 
-    if ((reg == 0x41) || (reg == 0x42) || (reg == 0x45) || (reg == 0x46) || (reg == 0x48) || (reg == 0x4a) || (reg >= 0x4c))
-	return;
+    switch (reg) {
+	case 0x00 ... 0x0f:
+	case 0x3f: case 0x41: case 0x42: case 0x4a:
+	case 0x4c ... 0x7f:
+		/* Read-only registers. */
+		return;
 
-    if ((reg == 0x40) && (val & 0x80)) {
-	val &= 0x7f;
-	vt82c686_reset(dev, 1);
+	case 0x40:
+		/* Reset if requested. */
+		if (val & 0x80) {
+			vt82c686_reset(dev, 1);
+			return;
+		}
+		break;
+
+	case 0x48:
+		val &= 0x7f;
+		break;
     }
 
     dev->regs[reg] = val;
@@ -106,7 +122,7 @@ vt82c686_hwm_write(uint8_t addr, uint8_t val, void *priv)
     vt82c686_t *dev = (vt82c686_t *) priv;
 
     if (dev->io_base)
-	io_removehandler(dev->io_base, 0x0050,
+	io_removehandler(dev->io_base, 128,
 			 vt82c686_read, NULL, NULL, vt82c686_write, NULL, NULL, dev);
 
     switch (addr) {
@@ -126,7 +142,7 @@ vt82c686_hwm_write(uint8_t addr, uint8_t val, void *priv)
     }
 
     if (dev->enable && dev->io_base)
-	io_sethandler(dev->io_base, 0x0050,
+	io_sethandler(dev->io_base, 128,
 		      vt82c686_read, NULL, NULL, vt82c686_write, NULL, NULL, dev);
 }
 
@@ -134,8 +150,10 @@ vt82c686_hwm_write(uint8_t addr, uint8_t val, void *priv)
 static void
 vt82c686_reset(vt82c686_t *dev, uint8_t initialization)
 {
-    memset(dev->regs, 0, 80);
+    memset(dev->regs, 0, sizeof(dev->regs));
 
+    dev->regs[0x17] = 0x80;
+    dev->regs[0x3f] = 0xa2;
     dev->regs[0x40] = 0x08;
     dev->regs[0x47] = 0x50;
     dev->regs[0x4b] = 0x15;
diff --git a/src/sio/sio_vt82c686.c b/src/sio/sio_vt82c686.c
index 3c887fce0..007ae6d93 100644
--- a/src/sio/sio_vt82c686.c
+++ b/src/sio/sio_vt82c686.c
@@ -34,7 +34,8 @@
 
 
 typedef struct {
-    uint8_t	cur_reg, regs[32], fdc_dma, fdc_irq, uart_irq[2], lpt_dma, lpt_irq;
+    uint8_t	cur_reg, last_val, regs[25],
+		fdc_dma, fdc_irq, uart_irq[2], lpt_dma, lpt_irq;
     fdc_t	*fdc;
     serial_t	*uart[2];
 } vt82c686_t;
@@ -43,10 +44,10 @@ typedef struct {
 static uint8_t
 get_lpt_length(vt82c686_t *dev)
 {
-    uint8_t length = 4;
+    uint8_t length = 4; /* non-EPP */
 
-    if ((dev->regs[0x02] & 0x03) == 0x2)
-	length = 8;
+    if ((dev->regs[0x02] & 0x03) == 0x02)
+	length = 8; /* EPP */
 
     return length;
 }
@@ -64,6 +65,7 @@ vt82c686_fdc_handler(vt82c686_t *dev)
 
     fdc_set_dma_ch(dev->fdc, dev->fdc_dma);
     fdc_set_irq(dev->fdc, dev->fdc_irq);
+    fdc_set_swap(dev->fdc, dev->regs[0x16] & 0x01);
 }
 
 
@@ -73,16 +75,20 @@ vt82c686_lpt_handler(vt82c686_t *dev)
     uint16_t io_mask, io_base = dev->regs[0x06] << 2;
     int io_len = get_lpt_length(dev);
     io_base &= (0xff8 | io_len);
-    io_mask = 0x3fc;
+    io_mask = 0x3fc; /* non-EPP */
     if (io_len == 8)
-	io_mask = 0x3f8;
+	io_mask = 0x3f8; /* EPP */
 
     lpt1_remove();
 
     if (((dev->regs[0x02] & 0x03) != 0x03) && (io_base >= 0x100) && (io_base <= io_mask))
 	lpt1_init(io_base);
 
-    lpt1_irq(dev->lpt_irq);
+    if (dev->lpt_irq) {
+	lpt1_irq(dev->lpt_irq);
+    } else {
+	lpt1_irq(0xff);
+    }
 }
 
 
@@ -91,8 +97,8 @@ vt82c686_serial_handler(vt82c686_t *dev, int uart)
 {
     serial_remove(dev->uart[uart]);
 
-    if (dev->regs[0x02] & (uart ? 0x08 : 0x04))
-	serial_setup(dev->uart[uart], (dev->regs[0x07 + uart] & 0xfe) << 2, dev->uart_irq[uart]);
+    if (dev->regs[0x02] & (0x04 << uart))
+	serial_setup(dev->uart[uart], dev->regs[0x07 + uart] << 2, dev->uart_irq[uart]);
 }
 
 
@@ -101,25 +107,31 @@ vt82c686_write(uint16_t port, uint8_t val, void *priv)
 {
     vt82c686_t *dev = (vt82c686_t *) priv;
 
+    /* Store last written value for echo (see comment on read). */
+    dev->last_val = val;
+
+    /* Write current register index on port 0. */
     if (!(port & 1)) {
 	dev->cur_reg = val;
 	return;
     }
 
-    /* NOTE: Registers are [0xE0:0xFF] but we store them as [0x00:0x1F]. */
-    if (dev->cur_reg < 0xe0)
-    	return;
+    /* NOTE: Registers are [0xE0:0xF8] but we store them as [0x00:0x18]. */
+    if ((dev->cur_reg < 0xe0) || (dev->cur_reg > 0xf8))
+	return;
     uint8_t reg = dev->cur_reg & 0x1f;
 
-    /* Read-only registers */
-    if ((reg < 0x02) || (reg == 0x04) || (reg == 0x05) || ((reg >= 0x09) && (reg < 0x0e)) ||
-	(reg == 0x13) || (reg == 0x15) || (reg == 0x17) || (reg >= 0x19))
+    /* Read-only registers. */
+    if ((reg < 0x02) || (reg == 0x0c))
 	return;
 
+    /* Write current register value on port 1. */
     dev->regs[reg] = val;
 
+    /* Update device state. */
     switch (reg) {
 	case 0x02:
+		dev->regs[reg] &= 0xbf;
 		vt82c686_lpt_handler(dev);
 		vt82c686_serial_handler(dev, 0);
 		vt82c686_serial_handler(dev, 1);
@@ -127,19 +139,54 @@ vt82c686_write(uint16_t port, uint8_t val, void *priv)
 		break;
 
 	case 0x03:
+		dev->regs[reg] &= 0xfc;
 		vt82c686_fdc_handler(dev);
 		break;
 
+	case 0x04:
+		dev->regs[reg] &= 0xfc;
+		break;
+
+	case 0x05:
+		dev->regs[reg] |= 0x03;
+		break;
+
 	case 0x06:
 		vt82c686_lpt_handler(dev);
 		break;
 
-	case 0x07:
-		vt82c686_serial_handler(dev, 0);
+	case 0x07: case 0x08:
+		dev->regs[reg] &= 0xfe;
+		vt82c686_serial_handler(dev, reg == 0x08);
 		break;
 
-	case 0x08:
-		vt82c686_serial_handler(dev, 1);
+	case 0x0d:
+		dev->regs[reg] &= 0x0f;
+		break;
+
+	case 0x0f:
+		dev->regs[reg] &= 0x7f;
+		break;
+
+	case 0x10:
+		dev->regs[reg] &= 0xf4;
+		break;
+
+	case 0x11:
+		dev->regs[reg] &= 0x3f;
+		break;
+
+	case 0x13:
+		dev->regs[reg] &= 0xfb;
+		break;
+
+	case 0x14: case 0x17:
+		dev->regs[reg] &= 0xfe;
+		break;
+
+	case 0x16:
+		dev->regs[reg] &= 0xf7;
+		vt82c686_fdc_handler(dev);
 		break;
     }
 }
@@ -149,17 +196,16 @@ static uint8_t
 vt82c686_read(uint16_t port, void *priv)
 {
     vt82c686_t *dev = (vt82c686_t *) priv;
-    uint8_t ret = 0xff;
 
-    /* NOTE: Registers are [0xE0:0xFF] but we store them as [0x00:0x1F]. */
+    /* NOTE: Registers are [0xE0:0xF8] but we store them as [0x00:0x18].
+       Real 686B echoes the last read/written value when reading from
+       registers outside that range. */
     if (!(port & 1))
-	ret = dev->cur_reg;
-    else if (dev->cur_reg < 0xe0)
-	ret = 0xff;
-    else
-	ret = dev->regs[dev->cur_reg & 0x1f];
+	dev->last_val = dev->cur_reg;
+    else if ((dev->cur_reg >= 0xe0) && (dev->cur_reg <= 0xf8))
+	dev->last_val = dev->regs[dev->cur_reg & 0x1f];
 
-    return ret;
+    return dev->last_val;
 }
 
 
@@ -205,7 +251,7 @@ static void
 vt82c686_reset(vt82c686_t *dev)
 {
     memset(dev->regs, 0, 20);
-    
+
     dev->regs[0x00] = 0x3c;
     dev->regs[0x02] = 0x03;
     dev->regs[0x03] = 0xfc;

From ceea08f032662976d335e156136d18c5108355bc Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 13:17:49 -0300
Subject: [PATCH 42/52] Implement full CS423x RAM access (assumed 64k)

---
 src/sound/snd_cs423x.c | 55 ++++++++++++++++++------------------------
 1 file changed, 24 insertions(+), 31 deletions(-)

diff --git a/src/sound/snd_cs423x.c b/src/sound/snd_cs423x.c
index 17b386360..dadce7672 100644
--- a/src/sound/snd_cs423x.c
+++ b/src/sound/snd_cs423x.c
@@ -133,9 +133,9 @@ typedef struct cs423x_t
     void	*gameport;
     void	*i2c, *eeprom;
 
-    uint16_t	wss_base, opl_base, sb_base, ctrl_base, ram_addr, eeprom_size: 11;
-    uint8_t	type, ad1848_type, pnp_offset, regs[8], indirect_regs[16],
-		eeprom_data[2048], ram_data[384], ram_dl: 2, opl_wss: 1;
+    uint16_t	wss_base, opl_base, sb_base, ctrl_base, ram_addr, eeprom_size: 11, pnp_offset;
+    uint8_t	type, ad1848_type, regs[8], indirect_regs[16],
+		eeprom_data[2048], ram_data[65536], ram_dl: 2, opl_wss: 1;
     char	*nvr_path;
 
     uint8_t	pnp_enable: 1, key_pos: 5, slam_enable: 1, slam_state: 2, slam_ld, slam_reg;
@@ -181,14 +181,9 @@ cs423x_read(uint16_t addr, void *priv)
 		break;
 
 	case 5: /* Control/RAM Access */
-		/* Reading RAM is undocumented; the WDM driver does so. */
-		if (dev->ram_dl == 3) {
-			if ((dev->ram_addr >= 0x4000) && (dev->ram_addr < 0x4180)) /* chip configuration and PnP resources */
-				ret = dev->ram_data[dev->ram_addr & 0x01ff];
-			else
-				ret = 0xff;
-			dev->ram_addr++;
-		}
+		/* Reading RAM is undocumented; the Windows drivers do so. */
+		if (dev->ram_dl == 3)
+			ret = dev->ram_data[dev->ram_addr++];
 		break;
 
 	case 7: /* Global Status */
@@ -311,9 +306,7 @@ cs423x_write(uint16_t addr, uint8_t val, void *priv)
 				break;
 
 			case 3: /* data */
-				if ((dev->ram_addr >= 0x4000) && (dev->ram_addr < 0x4180)) /* chip configuration and PnP resources */
-					dev->ram_data[dev->ram_addr & 0x01ff] = val;
-				dev->ram_addr++;
+				dev->ram_data[dev->ram_addr++] = val;
 				break;
 		}
 		break;
@@ -468,7 +461,7 @@ cs423x_slam_enable(cs423x_t *dev, uint8_t enable)
     }
 
     /* Enable SLAM if the CKD bit is not set. */
-    if (enable && !(dev->ram_data[2] & 0x10)) {
+    if (enable && !(dev->ram_data[0x4002] & 0x10)) {
 	dev->slam_enable = 1;
 	io_sethandler(0x279, 1, NULL, NULL, NULL, cs423x_slam_write, NULL, NULL, dev);
     }
@@ -543,25 +536,22 @@ cs423x_get_buffer(int32_t *buffer, int len, void *priv)
 static void
 cs423x_pnp_enable(cs423x_t *dev, uint8_t update_rom, uint8_t update_hwconfig)
 {
-    uint8_t enable = ISAPNP_CARD_ENABLE;
-
     if (dev->pnp_card) {
-	/* Hide PnP card if the PKD bit is set, or if PnP was disabled by command 0x55. */
-	if ((dev->ram_data[2] & 0x20) || !dev->pnp_enable)
-		enable = ISAPNP_CARD_DISABLE;
-
 	/* Update PnP resource data if requested. */
 	if (update_rom)
 		isapnp_update_card_rom(dev->pnp_card, &dev->ram_data[dev->pnp_offset], sizeof(dev->ram_data) - dev->pnp_offset);
 
-	/* Update PnP state. */
-	isapnp_enable_card(dev->pnp_card, enable);
+	/* Hide PnP card if the PKD bit is set, or if PnP was disabled by command 0x55. */
+	if ((dev->ram_data[0x4002] & 0x20) || !dev->pnp_enable)
+		isapnp_enable_card(dev->pnp_card, ISAPNP_CARD_DISABLE);
+	else
+		isapnp_enable_card(dev->pnp_card, ISAPNP_CARD_ENABLE);
     }
 
     /* Update some register bits based on the config data in RAM if requested. */
     if (update_hwconfig) {
 	/* Update WTEN. */
-	if (dev->ram_data[3] & 0x08) {
+	if (dev->ram_data[0x4003] & 0x08) {
 		dev->indirect_regs[8] |= 0x08;
 		dev->ad1848.wten = 1;
 	} else {
@@ -570,13 +560,13 @@ cs423x_pnp_enable(cs423x_t *dev, uint8_t update_rom, uint8_t update_hwconfig)
 	}
 
 	/* Update SPS. */
-	if (dev->ram_data[3] & 0x04)
+	if (dev->ram_data[0x4003] & 0x04)
 		dev->indirect_regs[8] |= 0x04;
 	else
 		dev->indirect_regs[8] &= ~0x04;
 
 	/* Update IFM. */
-	if (dev->ram_data[3] & 0x80)
+	if (dev->ram_data[0x4003] & 0x80)
 		dev->ad1848.xregs[4] |= 0x10;
 	else
 		dev->ad1848.xregs[4] &= ~0x10;
@@ -693,17 +683,20 @@ cs423x_reset(void *priv)
 {
     cs423x_t *dev = (cs423x_t *) priv;
 
-    /* Load EEPROM data to RAM, or just clear RAM if there's no EEPROM. */
+    /* Clear RAM. */
+    memset(dev->ram_data, 0, sizeof(dev->ram_data));
+
     if (dev->eeprom) {
-	memcpy(dev->ram_data, &dev->eeprom_data[4], MIN(sizeof(dev->ram_data), sizeof(dev->eeprom_data) - 4));
+	/* Load EEPROM data to RAM. */
+	memcpy(&dev->ram_data[0x4000], &dev->eeprom_data[4], MIN(384, ((dev->eeprom_data[2] << 8) | dev->eeprom_data[3]) - 4));
 
 	/* Save EEPROM contents to file. */
 	cs423x_nvram(dev, 1);
-    } else {
-	memset(dev->ram_data, 0, sizeof(dev->ram_data));
     }
 
     /* Reset registers. */
+    memset(dev->regs, 0, sizeof(dev->regs));
+    dev->regs[1] = 0x80;
     memset(dev->indirect_regs, 0, sizeof(dev->indirect_regs));
     dev->indirect_regs[1] = dev->type;
     if (dev->type == CRYSTAL_CS4238B)
@@ -737,7 +730,7 @@ cs423x_init(const device_t *info)
 	case CRYSTAL_CS4238B:
 		/* Same WSS codec and EEPROM structure. */
 		dev->ad1848_type = AD1848_TYPE_CS4236;
-		dev->pnp_offset = 19;
+		dev->pnp_offset = 0x4013;
 
 		/* Different Chip Version and ID registers, which shouldn't be reset by ad1848_init */
 		dev->ad1848.xregs[25] = dev->type;

From b58fda26e9d4f392b5452a81710b7aa0558c99e3 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 13:18:05 -0300
Subject: [PATCH 43/52] Remove VIA AC97 debug logging

---
 src/sound/snd_ac97_via.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 3d9956ae7..fd0f81c9d 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -166,13 +166,11 @@ ac97_via_update_irqs(ac97_via_t *dev)
 	/* Stop immediately if any flag is set. Doing it this way optimizes
 	   rising edges for the playback SGD (0 - first to be checked). */
 	if (dev->sgd_regs[i] & (dev->sgd_regs[i | 0x2] & 0x03)) {
-		pclog("irq set\n");
 		pci_set_irq(dev->slot, dev->irq_pin);
 		return;
 	}
     }
 
-    pclog("irq cleared\n");
     pci_clear_irq(dev->slot, dev->irq_pin);
 }
 

From 79c395afa66ffe84cccbefa40b9a0dead2ed0126 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 13:18:34 -0300
Subject: [PATCH 44/52] Fix small CS423x oversight

---
 src/sound/snd_cs423x.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/sound/snd_cs423x.c b/src/sound/snd_cs423x.c
index dadce7672..f3d95828d 100644
--- a/src/sound/snd_cs423x.c
+++ b/src/sound/snd_cs423x.c
@@ -539,7 +539,7 @@ cs423x_pnp_enable(cs423x_t *dev, uint8_t update_rom, uint8_t update_hwconfig)
     if (dev->pnp_card) {
 	/* Update PnP resource data if requested. */
 	if (update_rom)
-		isapnp_update_card_rom(dev->pnp_card, &dev->ram_data[dev->pnp_offset], sizeof(dev->ram_data) - dev->pnp_offset);
+		isapnp_update_card_rom(dev->pnp_card, &dev->ram_data[dev->pnp_offset], 384);
 
 	/* Hide PnP card if the PKD bit is set, or if PnP was disabled by command 0x55. */
 	if ((dev->ram_data[0x4002] & 0x20) || !dev->pnp_enable)

From 8889e9477f829cddce4c834071100d9694d11b0d Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 16:39:46 -0300
Subject: [PATCH 45/52] Switch UM8669F dummy device to the more technically
 correct PNPFFFF

---
 src/sio/sio_um8669f.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/sio/sio_um8669f.c b/src/sio/sio_um8669f.c
index 516685629..6fd2d1477 100644
--- a/src/sio/sio_um8669f.c
+++ b/src/sio/sio_um8669f.c
@@ -61,7 +61,7 @@ static uint8_t um8669f_pnp_rom[] = {
 	0x22, 0xfa, 0x1f, /* IRQ 1/3/4/5/6/7/8/9/10/11/12 */
 	0x47, 0x00, 0x00, 0x01, 0xf8, 0x03, 0x08, 0x08, /* I/O 0x100-0x3F8, decodes 10-bit, 8-byte alignment, 8 addresses */
 
-    0x15, 0x55, 0xa3, 0x86, 0x69, 0x00, /* logical device UMC8669 (just a dummy to create a gap in LDNs) */
+    0x15, 0x41, 0xd0, 0xff, 0xff, 0x00, /* logical device PNPFFFF (just a dummy to create a gap in LDNs) */
 
     0x15, 0x41, 0xd0, 0xb0, 0x2f, 0x01, /* logical device PNPB02F, can participate in boot */
 	0x47, 0x00, 0x00, 0x01, 0xf8, 0x03, 0x08, 0x08, /* I/O 0x100-0x3F8, decodes 10-bit, 8-byte alignment, 8 addresses */

From f0176ceab672e9d95d482abcf0a5c5da05e201ff Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 16:43:58 -0300
Subject: [PATCH 46/52] Sound Blaster PnP/IDE overhaul, closes 86Box#1578

---
 src/disk/hdc_ide.c          |  66 ++++--
 src/include/86box/hdc.h     |   2 +
 src/include/86box/hdc_ide.h |   3 +
 src/include/86box/snd_sb.h  |   2 +-
 src/sound/snd_sb.c          | 407 ++++++++++++++----------------------
 5 files changed, 214 insertions(+), 266 deletions(-)

diff --git a/src/disk/hdc_ide.c b/src/disk/hdc_ide.c
index f7740fab8..c0cc93159 100644
--- a/src/disk/hdc_ide.c
+++ b/src/disk/hdc_ide.c
@@ -2765,7 +2765,7 @@ ide_board_init(int board, int irq, int base_main, int side_main, int type)
 }
 
 
-static void
+void
 ide_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *priv)
 {
     if (ld)
@@ -2796,12 +2796,23 @@ ide_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *priv)
 static void *
 ide_ter_init(const device_t *info)
 {
-    int irq = device_get_config_int("irq");
-    if (irq == -1) {
-	ide_board_init(2, -1, 0, 0, info->local);
-	isapnp_add_card(ide_ter_pnp_rom, sizeof(ide_ter_pnp_rom), ide_pnp_config_changed, NULL, NULL, NULL, (void *) 2);
-    } else
-	ide_board_init(2, irq, 0x168, 0x36e, info->local);
+    /* Don't claim this channel again if it was already claimed. */
+    if (ide_boards[2])
+	return(NULL);
+
+    int irq;
+    if (info->local)
+	irq = -2;
+    else
+	irq = device_get_config_int("irq");
+
+    if (irq < 0) {
+	ide_board_init(2, -1, 0, 0, 0);
+	if (irq == -1)
+		isapnp_add_card(ide_ter_pnp_rom, sizeof(ide_ter_pnp_rom), ide_pnp_config_changed, NULL, NULL, NULL, (void *) 2);
+    } else {
+	ide_board_init(2, irq, 0x168, 0x36e, 0);
+    }
 
     return(ide_boards[2]);
 }
@@ -2818,12 +2829,23 @@ ide_ter_close(void *priv)
 static void *
 ide_qua_init(const device_t *info)
 {
-    int irq = device_get_config_int("irq");
-    if (irq == -1) {
-	ide_board_init(3, -1, 0, 0, info->local);
-	isapnp_add_card(ide_qua_pnp_rom, sizeof(ide_qua_pnp_rom), ide_pnp_config_changed, NULL, NULL, NULL, (void *) 3);
-    } else
-	ide_board_init(3, irq, 0x1e8, 0x3ee, info->local);
+    /* Don't claim this channel again if it was already claimed. */
+    if (ide_boards[3])
+	return(NULL);
+
+    int irq;
+    if (info->local)
+	irq = -2;
+    else
+	irq = device_get_config_int("irq");
+
+    if (irq < 0) {
+	ide_board_init(3, -1, 0, 0, 0);
+	if (irq == -1)
+		isapnp_add_card(ide_qua_pnp_rom, sizeof(ide_qua_pnp_rom), ide_pnp_config_changed, NULL, NULL, NULL, (void *) 3);
+    } else {
+	ide_board_init(3, irq, 0x1e8, 0x3ee, 0);
+    }
 
     return(ide_boards[3]);
 }
@@ -3103,6 +3125,15 @@ const device_t ide_ter_device = {
     ide_ter_config
 };
 
+const device_t ide_ter_pnp_device = {
+    "Tertiary IDE Controller (Plug and Play only)",
+    DEVICE_AT,
+    1,
+    ide_ter_init, ide_ter_close, NULL,
+    { NULL }, NULL, NULL,
+    NULL
+};
+
 const device_t ide_qua_device = {
     "Quaternary IDE Controller",
     DEVICE_AT,
@@ -3111,3 +3142,12 @@ const device_t ide_qua_device = {
     { NULL }, NULL, NULL,
     ide_qua_config
 };
+
+const device_t ide_qua_pnp_device = {
+    "Quaternary IDE Controller (Plug and Play only)",
+    DEVICE_AT,
+    1,
+    ide_qua_init, ide_qua_close, NULL,
+    { NULL }, NULL, NULL,
+    ide_qua_config
+};
diff --git a/src/include/86box/hdc.h b/src/include/86box/hdc.h
index e840de3cf..9175dddaf 100644
--- a/src/include/86box/hdc.h
+++ b/src/include/86box/hdc.h
@@ -60,7 +60,9 @@ extern const device_t	ide_cmd640_pci_single_channel_device;	/* CMD PCI-640B PCI
 extern const device_t	ide_opti611_vlb_device;		/* OPTi 82c611/611A VLB */
 
 extern const device_t	ide_ter_device;
+extern const device_t	ide_ter_pnp_device;
 extern const device_t	ide_qua_device;
+extern const device_t	ide_qua_pnp_device;
 
 extern const device_t	xta_wdxt150_device;		/* xta_wdxt150 */
 extern const device_t	xta_hd20_device;		/* EuroPC internal */
diff --git a/src/include/86box/hdc_ide.h b/src/include/86box/hdc_ide.h
index 48b7c8939..20742004e 100644
--- a/src/include/86box/hdc_ide.h
+++ b/src/include/86box/hdc_ide.h
@@ -136,6 +136,9 @@ extern void	ide_sec_enable(void);
 extern void	ide_sec_disable(void);
 
 extern void	ide_board_set_force_ata3(int board, int force_ata3);
+#ifdef EMU_ISAPNP_H
+extern void	ide_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *priv);
+#endif
 
 extern double	ide_atapi_get_period(uint8_t channel);
 #ifdef SCSI_DEVICE_H
diff --git a/src/include/86box/snd_sb.h b/src/include/86box/snd_sb.h
index cb850584c..8641a58f2 100644
--- a/src/include/86box/snd_sb.h
+++ b/src/include/86box/snd_sb.h
@@ -125,7 +125,7 @@ typedef struct sb_t
 
         int pos;
         
-        uint8_t pos_regs[8];
+        uint8_t pos_regs[8], pnp_rom[512];
 
         uint16_t opl_pnp_addr;
 } sb_t;
diff --git a/src/sound/snd_sb.c b/src/sound/snd_sb.c
index 1d81447c8..287de664e 100644
--- a/src/sound/snd_sb.c
+++ b/src/sound/snd_sb.c
@@ -38,6 +38,8 @@
 #include <86box/filters.h>
 #include <86box/isapnp.h>
 #include <86box/snd_sb.h>
+#include <86box/hdc.h>
+#include <86box/hdc_ide.h>
 
 
 /* 0 to 7 -> -14dB to 0dB i 2dB steps. 8 to 15 -> 0 to +14dB in 2dB steps.
@@ -73,24 +75,81 @@ static const int sb_pro_mcv_irqs[4] = {7, 5, 3, 3};
 
 
 /* Each card in the SB16 family has a million variants, and it shows in the large variety of device IDs for the PnP models.
-   These ROMs were reconstructed in a best-effort basis, around what Linux pnpdump configs and kernel logs could be found
-   in mailing lists, forums and other places, as well as Linux's own SB PnP card tables for ALSA and OSS. */
+   This ROM was reconstructed in a best-effort basis around a pnpdump output log found in a forum. */
 static uint8_t sb_16_pnp_rom[] = {
-    0x0e, 0x8c, 0x00, 0x28, 0x00, 0x00, 0x00, 0x00, 0x00, /* CTL0028, dummy checksum (filled in by isapnp_add_card) */
+    0x0e, 0x8c, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00, 0x00, /* CTL0024, dummy checksum (filled in by isapnp_add_card) */
     0x0a, 0x10, 0x10, /* PnP version 1.0, vendor version 1.0 */
     0x82, 0x11, 0x00, 'C', 'r', 'e', 'a', 't', 'i', 'v', 'e', ' ', 'S', 'B', '1', '6', ' ', 'P', 'n', 'P', /* ANSI identifier */
 
-    0x15, 0x0e, 0x8c, 0x00, 0x31, 0x00, /* logical device CTL0031 */
+    0x16, 0x0e, 0x8c, 0x00, 0x31, 0x00, 0x65, /* logical device CTL0031, supports vendor-specific registers 0x39/0x3A/0x3D/0x3F */
 	0x82, 0x05, 0x00, 'A', 'u', 'd', 'i', 'o', /* ANSI identifier */
-	0x30, /* start dependent functions, acceptable */
+	0x31, 0x00, /* start dependent functions, preferred */
+		0x22, 0x20, 0x00, /* IRQ 5 */
+		0x2a, 0x02, 0x08, /* DMA 1, compatibility, no count by word, count by byte, not bus master, 8-bit only */
+		0x2a, 0x20, 0x12, /* DMA 5, compatibility, count by word, no count by byte, not bus master, 16-bit only */
+		0x47, 0x01, 0x20, 0x02, 0x20, 0x02, 0x01, 0x10, /* I/O 0x220, decodes 16-bit, 1-byte alignment, 16 addresses */
+		0x47, 0x01, 0x30, 0x03, 0x30, 0x03, 0x01, 0x02, /* I/O 0x330, decodes 16-bit, 1-byte alignment, 2 addresses */
+		0x47, 0x01, 0x88, 0x03, 0x88, 0x03, 0x01, 0x04, /* I/O 0x388, decodes 16-bit, 1-byte alignment, 4 addresses */
+	0x31, 0x01, /* start dependent functions, acceptable */
 		0x22, 0xa0, 0x04, /* IRQ 5/7/10 */
 		0x2a, 0x0b, 0x08, /* DMA 0/1/3, compatibility, no count by word, count by byte, not bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
+		0x2a, 0xe0, 0x12, /* DMA 5/6/7, compatibility, count by word, no count by byte, not bus master, 16-bit only */
 		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
 		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
 		0x47, 0x01, 0x88, 0x03, 0x88, 0x03, 0x01, 0x04, /* I/O 0x388, decodes 16-bit, 1-byte alignment, 4 addresses */
+	0x31, 0x01, /* start dependent functions, acceptable */
+		0x22, 0xa0, 0x04, /* IRQ 5/7/10 */
+		0x2a, 0x0b, 0x08, /* DMA 0/1/3, compatibility, no count by word, count by byte, not bus master, 8-bit only */
+		0x2a, 0xe0, 0x12, /* DMA 5/6/7, compatibility, count by word, no count by byte, not bus master, 16-bit only */
+		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
+		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
+	0x31, 0x02, /* start dependent functions, functional */
+		0x22, 0xa0, 0x04, /* IRQ 5/7/10 */
+		0x2a, 0x0b, 0x08, /* DMA 0/1/3, compatibility, no count by word, count by byte, not bus master, 8-bit only */
+		0x2a, 0xe0, 0x12, /* DMA 5/6/7, compatibility, count by word, no count by byte, not bus master, 16-bit only */
+		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
+	0x31, 0x02, /* start dependent functions, functional */
+		0x22, 0xa0, 0x04, /* IRQ 5/7/10 */
+		0x2a, 0x0b, 0x08, /* DMA 0/1/3, compatibility, no count by word, count by byte, not bus master, 8-bit only */
+		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
+		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
+		0x47, 0x01, 0x88, 0x03, 0x88, 0x03, 0x01, 0x04, /* I/O 0x388, decodes 16-bit, 1-byte alignment, 4 addresses */
+	0x31, 0x02, /* start dependent functions, functional */
+		0x22, 0xa0, 0x04, /* IRQ 5/7/10 */
+		0x2a, 0x0b, 0x08, /* DMA 0/1/3, compatibility, no count by word, count by byte, not bus master, 8-bit only */
+		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
+		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
+	0x31, 0x02, /* start dependent functions, functional */
+		0x22, 0xa0, 0x04, /* IRQ 5/7/10 */
+		0x2a, 0x0b, 0x08, /* DMA 0/1/3, compatibility, no count by word, count by byte, not bus master, 8-bit only */
+		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
 	0x38, /* end dependent functions */
 
+    0x16, 0x0e, 0x8c, 0x20, 0x11, 0x00, 0x5a, /* logical device CTL2011, supports vendor-specific registers 0x39/0x3B/0x3C/0x3E */
+	0x1c, 0x41, 0xd0, 0x06, 0x00, /* compatible device PNP0600 */
+	0x82, 0x03, 0x00, 'I', 'D', 'E', /* ANSI identifier */
+	0x31, 0x00, /* start dependent functions, preferred */
+		0x22, 0x00, 0x04, /* IRQ 10 */
+		0x47, 0x01, 0x68, 0x01, 0x68, 0x01, 0x01, 0x08, /* I/O 0x168, decodes 16-bit, 1-byte alignment, 8 addresses */
+		0x47, 0x01, 0x6e, 0x03, 0x6e, 0x03, 0x01, 0x02, /* I/O 0x36E, decodes 16-bit, 1-byte alignment, 2 addresses */
+	0x31, 0x01, /* start dependent functions, acceptable */
+		0x22, 0x00, 0x08, /* IRQ 11 */
+		0x47, 0x01, 0xe8, 0x01, 0xe8, 0x01, 0x01, 0x08, /* I/O 0x1E8, decodes 16-bit, 1-byte alignment, 8 addresses */
+		0x47, 0x01, 0xee, 0x03, 0xee, 0x03, 0x01, 0x02, /* I/O 0x3EE, decodes 16-bit, 1-byte alignment, 2 addresses */
+	0x31, 0x01, /* start dependent functions, acceptable */
+		0x22, 0x00, 0x8c, /* IRQ 10/11/15 */
+		0x47, 0x01, 0x00, 0x01, 0xf8, 0x01, 0x08, 0x08, /* I/O 0x100-0x1F8, decodes 16-bit, 8-byte alignment, 8 addresses */
+		0x47, 0x01, 0x00, 0x03, 0xfe, 0x03, 0x02, 0x02, /* I/O 0x300-0x3FE, decodes 16-bit, 2-byte alignment, 2 addresses */
+	0x31, 0x02, /* start dependent functions, functional */
+		0x22, 0x00, 0x80, /* IRQ 15 */
+		0x47, 0x01, 0x70, 0x01, 0x70, 0x01, 0x01, 0x08, /* I/O 0x170, decodes 16-bit, 1-byte alignment, 8 addresses */
+		0x47, 0x01, 0x76, 0x03, 0x76, 0x03, 0x01, 0x02, /* I/O 0x376, decodes 16-bit, 1-byte alignment, 1 addresses */
+	0x38, /* end dependent functions */
+
+    0x16, 0x41, 0xd0, 0xff, 0xff, 0x00, 0xda, /* logical device PNPFFFF, supports vendor-specific registers 0x38/0x39/0x3B/0x3C/0x3E */
+	0x82, 0x08, 0x00, 'R', 'e', 's', 'e', 'r', 'v', 'e', 'd', /* ANSI identifier */
+	0x47, 0x01, 0x00, 0x01, 0xf8, 0x03, 0x08, 0x01, /* I/O 0x100-0x3F8, decodes 16-bit, 8-byte alignment, 1 address */
+
     0x15, 0x0e, 0x8c, 0x70, 0x01, 0x00, /* logical device CTL7001 */
 	0x1c, 0x41, 0xd0, 0xb0, 0x2f, /* compatible device PNPB02F */
 	0x82, 0x04, 0x00, 'G', 'a', 'm', 'e', /* ANSI identifier */
@@ -98,227 +157,6 @@ static uint8_t sb_16_pnp_rom[] = {
 
     0x79, 0x00 /* end tag, dummy checksum (filled in by isapnp_add_card) */
 };
-static uint8_t sb_32_pnp_rom[] = {
-    0x0e, 0x8c, 0x00, 0x48, 0x00, 0x00, 0x00, 0x00, 0x00, /* CTL0048, dummy checksum (filled in by isapnp_add_card) */
-    0x0a, 0x10, 0x10, /* PnP version 1.0, vendor version 1.0 */
-    0x82, 0x11, 0x00, 'C', 'r', 'e', 'a', 't', 'i', 'v', 'e', ' ', 'S', 'B', '3', '2', ' ', 'P', 'n', 'P', /* ANSI identifier */
-
-    0x16, 0x0e, 0x8c, 0x00, 0x31, 0x00, 0xa9, /* logical device CTL0031, supports vendor-specific registers 0x38/0x3A/0x3C/0x3F */
-	0x82, 0x05, 0x00, 'A', 'u', 'd', 'i', 'o', /* ANSI identifier */
-	0x31, 0x00, /* start dependent functions, preferred */
-		0x22, 0x20, 0x00, /* IRQ 5 */
-		0x2a, 0x02, 0x0c, /* DMA 1, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0x20, 0x16, /* DMA 5, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x20, 0x02, 0x01, 0x10, /* I/O 0x220, decodes 16-bit, 1-byte alignment, 16 addresses */
-		0x47, 0x01, 0x30, 0x03, 0x30, 0x03, 0x01, 0x02, /* I/O 0x330, decodes 16-bit, 1-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0x88, 0x03, 0x01, 0x04, /* I/O 0x388, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0x88, 0x03, 0x01, 0x04, /* I/O 0x388, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0x88, 0x03, 0x01, 0x04, /* I/O 0x388, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0x94, 0x03, 0x04, 0x04, /* I/O 0x388-0x394, decodes 16-bit, 4-byte alignment, 4 addresses */
-	0x38, /* end dependent functions */
-
-    0x16, 0x0e, 0x8c, 0x00, 0x21, 0x00, 0xa9, /* logical device CTL0021, supports vendor-specific registers 0x38/0x3A/0x3C/0x3F */
-	0x82, 0x09, 0x00, 'W', 'a', 'v', 'e', 'T', 'a', 'b', 'l', 'e', /* ANSI identifier */
-	0x31, 0x00, /* start dependent functions, preferred */
-		0x47, 0x01, 0x20, 0x06, 0x20, 0x06, 0x01, 0x04, /* I/O 0x620, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x47, 0x01, 0x20, 0x06, 0x80, 0x06, 0x20, 0x04, /* I/O 0x620-0x680, decodes 16-bit, 32-byte alignment, 4 addresses */
-	0x38, /* end dependent functions */
-
-    0x15, 0x0e, 0x8c, 0x70, 0x01, 0x00, /* logical device CTL7001 */
-	0x1c, 0x41, 0xd0, 0xb0, 0x2f, /* compatible device PNPB02F */
-	0x82, 0x04, 0x00, 'G', 'a', 'm', 'e', /* ANSI identifier */
-	0x47, 0x01, 0x00, 0x02, 0x00, 0x02, 0x01, 0x08, /* I/O 0x200, decodes 16-bit, 1-byte alignment, 8 addresses */
-
-    0x79, 0x00 /* end tag, dummy checksum (filled in by isapnp_add_card) */
-};
-static uint8_t sb_awe32_pnp_rom[] = {
-    0x0e, 0x8c, 0x00, 0x43, 0x00, 0x00, 0x00, 0x00, 0x00, /* CTL0043, dummy checksum (filled in by isapnp_add_card) */
-    0x0a, 0x10, 0x10, /* PnP version 1.0, vendor version 1.0 */
-    0x82, 0x15, 0x00, 'C', 'r', 'e', 'a', 't', 'i', 'v', 'e', ' ', 'S', 'B', ' ', 'A', 'W', 'E', '3', '2', ' ', 'P', 'n', 'P', /* ANSI identifier */
-
-    0x16, 0x0e, 0x8c, 0x00, 0x31, 0x00, 0xa9, /* logical device CTL0031, supports vendor-specific registers 0x38/0x3A/0x3C/0x3F */
-	0x82, 0x05, 0x00, 'A', 'u', 'd', 'i', 'o', /* ANSI identifier */
-	0x31, 0x00, /* start dependent functions, preferred */
-		0x22, 0x20, 0x00, /* IRQ 5 */
-		0x2a, 0x02, 0x0c, /* DMA 1, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0x20, 0x16, /* DMA 5, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x20, 0x02, 0x01, 0x10, /* I/O 0x220, decodes 16-bit, 1-byte alignment, 16 addresses */
-		0x47, 0x01, 0x30, 0x03, 0x30, 0x03, 0x01, 0x02, /* I/O 0x330, decodes 16-bit, 1-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0xf8, 0x03, 0x01, 0x04, /* I/O 0x388-0x3F8, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0x88, 0x03, 0x01, 0x04, /* I/O 0x388, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0x88, 0x03, 0x01, 0x04, /* I/O 0x388, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-	0x31, 0x02, /* start dependent functions, sub-optimal */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0x94, 0x03, 0x04, 0x04, /* I/O 0x388-0x394, decodes 16-bit, 4-byte alignment, 4 addresses */
-	0x38, /* end dependent functions */
-
-    0x16, 0x0e, 0x8c, 0x00, 0x21, 0x00, 0xa9, /* logical device CTL0021, supports vendor-specific registers 0x38/0x3A/0x3C/0x3F */
-	0x82, 0x09, 0x00, 'W', 'a', 'v', 'e', 'T', 'a', 'b', 'l', 'e', /* ANSI identifier */
-	0x31, 0x00, /* start dependent functions, preferred */
-		0x47, 0x01, 0x20, 0x06, 0x20, 0x06, 0x01, 0x04, /* I/O 0x620, decodes 16-bit, 1-byte alignment, 4 addresses */
-		0x47, 0x01, 0x20, 0x0a, 0x20, 0x0a, 0x01, 0x04, /* I/O 0xA20, decodes 16-bit, 1-byte alignment, 4 addresses */
-		0x47, 0x01, 0x20, 0x0e, 0x20, 0x0e, 0x01, 0x04, /* I/O 0xE20, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x47, 0x01, 0x20, 0x06, 0x80, 0x06, 0x20, 0x04, /* I/O 0x620-0x680, decodes 16-bit, 32-byte alignment, 4 addresses */
-		0x47, 0x01, 0x20, 0x0a, 0x80, 0x0a, 0x20, 0x04, /* I/O 0xA20-0xA80, decodes 16-bit, 32-byte alignment, 4 addresses */
-		0x47, 0x01, 0x20, 0x0e, 0x80, 0x0e, 0x20, 0x04, /* I/O 0xE20-0xE80, decodes 16-bit, 32-byte alignment, 4 addresses */
-	0x38, /* end dependent functions */
-
-    0x15, 0x0e, 0x8c, 0x70, 0x01, 0x00, /* logical device CTL7001 */
-	0x1c, 0x41, 0xd0, 0xb0, 0x2f, /* compatible device PNPB02F */
-	0x82, 0x04, 0x00, 'G', 'a', 'm', 'e', /* ANSI identifier */
-	0x47, 0x01, 0x00, 0x02, 0x00, 0x02, 0x01, 0x08, /* I/O 0x200, decodes 16-bit, 1-byte alignment, 8 addresses */
-
-    0x79, 0x00 /* end tag, dummy checksum (filled in by isapnp_add_card) */
-};
-static uint8_t sb_awe64_gold_pnp_rom[] = {
-    0x0e, 0x8c, 0x00, 0x9e, 0x00, 0x00, 0x00, 0x00, 0x00, /* CTL009E, dummy checksum (filled in by isapnp_add_card) */
-    0x0a, 0x10, 0x20, /* PnP version 1.0, vendor version 2.0 */
-    0x82, 0x16, 0x00, 'C', 'r', 'e', 'a', 't', 'i', 'v', 'e', ' ', 'S', 'B', ' ', 'A', 'W', 'E', '6', '4', ' ', 'G', 'o', 'l', 'd', /* ANSI identifier */
-
-    0x16, 0x0e, 0x8c, 0x00, 0x44, 0x00, 0xa9, /* logical device CTL0044, supports vendor-specific registers 0x38/0x3A/0x3C/0x3F */
-	0x82, 0x05, 0x00, 'A', 'u', 'd', 'i', 'o', /* ANSI identifier */
-	0x31, 0x00, /* start dependent functions, preferred */
-		0x22, 0x20, 0x00, /* IRQ 5 */
-		0x2a, 0x02, 0x0c, /* DMA 1, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0x20, 0x16, /* DMA 5, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x20, 0x02, 0x01, 0x10, /* I/O 0x220, decodes 16-bit, 1-byte alignment, 16 addresses */
-		0x47, 0x01, 0x30, 0x03, 0x30, 0x03, 0x01, 0x02, /* I/O 0x330, decodes 16-bit, 1-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0xf8, 0x03, 0x01, 0x04, /* I/O 0x388-0x3F8, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0xf8, 0x03, 0x01, 0x04, /* I/O 0x388-0x3F8, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0xf8, 0x03, 0x01, 0x04, /* I/O 0x388-0x3F8, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-	0x31, 0x02, /* start dependent functions, sub-optimal */
-		0x22, 0xa0, 0x06, /* IRQ 5/7/9/10 */
-		0x2a, 0x0b, 0x0c, /* DMA 0/1/3, compatibility, no count by word, count by byte, is bus master, 8-bit only */
-		0x2a, 0xe0, 0x16, /* DMA 5/6/7, compatibility, count by word, no count by byte, is bus master, 16-bit only */
-		0x47, 0x01, 0x20, 0x02, 0x80, 0x02, 0x20, 0x10, /* I/O 0x220-0x280, decodes 16-bit, 32-byte alignment, 16 addresses */
-		0x47, 0x01, 0x00, 0x03, 0x30, 0x03, 0x30, 0x02, /* I/O 0x300-0x330, decodes 16-bit, 48-byte alignment, 2 addresses */
-		0x47, 0x01, 0x88, 0x03, 0x94, 0x03, 0x04, 0x04, /* I/O 0x388-0x394, decodes 16-bit, 4-byte alignment, 4 addresses */
-	0x38, /* end dependent functions */
-
-    0x15, 0x0e, 0x8c, 0x70, 0x02, 0x00, /* logical device CTL7002 */
-	0x1c, 0x41, 0xd0, 0xb0, 0x2f, /* compatible device PNPB02F */
-	0x82, 0x04, 0x00, 'G', 'a', 'm', 'e', /* ANSI identifier */
-	0x47, 0x01, 0x00, 0x02, 0x00, 0x02, 0x01, 0x08, /* I/O 0x200, decodes 16-bit, 1-byte alignment, 8 addresses */
-
-    0x16, 0x0e, 0x8c, 0x00, 0x23, 0x00, 0xa9, /* logical device CTL0023, supports vendor-specific registers 0x38/0x3A/0x3C/0x3F */
-	0x82, 0x09, 0x00, 'W', 'a', 'v', 'e', 'T', 'a', 'b', 'l', 'e', /* ANSI identifier */
-	0x31, 0x00, /* start dependent functions, preferred */
-		0x47, 0x01, 0x20, 0x06, 0x20, 0x06, 0x01, 0x04, /* I/O 0x620, decodes 16-bit, 1-byte alignment, 4 addresses */
-		0x47, 0x01, 0x20, 0x0a, 0x20, 0x0a, 0x01, 0x04, /* I/O 0xA20, decodes 16-bit, 1-byte alignment, 4 addresses */
-		0x47, 0x01, 0x20, 0x0e, 0x20, 0x0e, 0x01, 0x04, /* I/O 0xE20, decodes 16-bit, 1-byte alignment, 4 addresses */
-	0x30, /* start dependent functions, acceptable */
-		0x47, 0x01, 0x20, 0x06, 0x80, 0x06, 0x20, 0x04, /* I/O 0x620-0x680, decodes 16-bit, 32-byte alignment, 4 addresses */
-		0x47, 0x01, 0x20, 0x0a, 0x80, 0x0a, 0x20, 0x04, /* I/O 0xA20-0xA80, decodes 16-bit, 32-byte alignment, 4 addresses */
-		0x47, 0x01, 0x20, 0x0e, 0x80, 0x0e, 0x20, 0x04, /* I/O 0xE20-0xE80, decodes 16-bit, 32-byte alignment, 4 addresses */
-	0x38, /* end dependent functions */
-
-    0x79, 0x00 /* end tag, dummy checksum (filled in by isapnp_add_card) */
-};
 
 
 #ifdef ENABLE_SB_LOG
@@ -1348,9 +1186,21 @@ sb_16_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *priv)
 
 		break;
 
-	case 1: /* Game */
+	case 1: /* IDE */
+		ide_pnp_config_changed(0, config, (void *) 2);
+		break;
+
+	case 2: /* Reserved (16) / WaveTable (32+) */
+		if (sb->dsp.sb_type > SB16)
+			emu8k_change_addr(&sb->emu8k, (config->activate && (config->io[0].base != ISAPNP_IO_DISABLED)) ? config->io[0].base : 0);
+		break;
+
+	case 3: /* Game */
 		gameport_remap(sb->gameport, (config->activate && (config->io[0].base != ISAPNP_IO_DISABLED)) ? config->io[0].base : 0);
 		break;
+
+	case 4: /* StereoEnhance (32) */
+		break;
     }
 }
 
@@ -1362,15 +1212,13 @@ sb_awe32_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *pr
 
     switch (ld) {
 	case 0: /* Audio */
-		sb_16_pnp_config_changed(0, config, sb);
-		break;
-
-	case 1: /* WaveTable */
-		emu8k_change_addr(&sb->emu8k, (config->activate && (config->io[0].base != ISAPNP_IO_DISABLED)) ? config->io[0].base : 0);
+	case 1: /* IDE */
+		sb_16_pnp_config_changed(ld, config, sb);
 		break;
 
 	case 2: /* Game */
-		sb_16_pnp_config_changed(1, config, sb);
+	case 3: /* WaveTable */
+		sb_16_pnp_config_changed(ld ^ 1, config, sb);
 		break;
     }
 }
@@ -1383,15 +1231,12 @@ sb_awe64_gold_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, voi
 
     switch (ld) {
 	case 0: /* Audio */
-		sb_16_pnp_config_changed(0, config, sb);
+	case 2: /* WaveTable */
+		sb_16_pnp_config_changed(ld, config, sb);
 		break;
 
 	case 1: /* Game */
-		sb_16_pnp_config_changed(1, config, sb);
-		break;
-
-	case 2: /* WaveTable */
-		emu8k_change_addr(&sb->emu8k, (config->activate && (config->io[0].base != ISAPNP_IO_DISABLED)) ? config->io[0].base : 0);
+		sb_16_pnp_config_changed(3, config, sb);
 		break;
     }
 }
@@ -1821,6 +1666,8 @@ sb_16_pnp_init(const device_t *info)
 
     sb->gameport = gameport_add(&gameport_pnp_device);
 
+    device_add(&ide_ter_pnp_device);
+
     isapnp_add_card(sb_16_pnp_rom, sizeof(sb_16_pnp_rom), sb_16_pnp_config_changed, NULL, NULL, NULL, sb);
 
     return sb;
@@ -1834,6 +1681,27 @@ sb_awe32_available()
 }
 
 
+static int
+sb_32_pnp_available()
+{
+    return sb_awe32_available() && rom_present("roms/sound/CT3600 PnP.BIN");
+}
+
+
+static int
+sb_awe32_pnp_available()
+{
+    return sb_awe32_available() && rom_present("roms/sound/CT3980 PnP.BIN");
+}
+
+
+static int
+sb_awe64_gold_available()
+{
+    return sb_awe32_available() && rom_present("roms/sound/CT4540 PnP.BIN");
+}
+
+
 static void *
 sb_awe32_init(const device_t *info)
 {
@@ -1899,7 +1767,7 @@ sb_awe32_pnp_init(const device_t *info)
     sb->opl_enabled = 1;
     opl3_init(&sb->opl);
 
-    sb_dsp_init(&sb->dsp, ((info->local == 2) ? SBAWE64 : SBAWE32), SB_SUBTYPE_DEFAULT, sb);
+    sb_dsp_init(&sb->dsp, (info->local == 2) ? SBAWE64 : SBAWE32, SB_SUBTYPE_DEFAULT, sb);
     sb_ct1745_mixer_reset(sb);
 
     sb->mixer_enabled = 1;
@@ -1918,12 +1786,47 @@ sb_awe32_pnp_init(const device_t *info)
 
     sb->gameport = gameport_add(&gameport_pnp_device);
 
-    if (info->local == 2)
-	isapnp_add_card(sb_awe64_gold_pnp_rom, sizeof(sb_awe64_gold_pnp_rom), sb_awe64_gold_pnp_config_changed, NULL, NULL, NULL, sb);
-    else if (info->local == 1)
-	isapnp_add_card(sb_32_pnp_rom, sizeof(sb_32_pnp_rom), sb_awe32_pnp_config_changed, NULL, NULL, NULL, sb);
-    else
-	isapnp_add_card(sb_awe32_pnp_rom, sizeof(sb_awe32_pnp_rom), sb_awe32_pnp_config_changed, NULL, NULL, NULL, sb);
+    if (info->local != 2)
+	device_add(&ide_ter_pnp_device);
+
+    char *pnp_rom_file = NULL;
+    switch (info->local) {
+	case 0:
+		pnp_rom_file = "roms/sound/CT3600 PnP.BIN";
+		break;
+
+	case 1:
+		pnp_rom_file = "roms/sound/CT3980 PnP.BIN";
+		break;
+
+	case 2:
+		pnp_rom_file = "roms/sound/CT4540 PnP.BIN";
+		break;
+    }
+
+    uint8_t *pnp_rom = NULL;
+    if (pnp_rom_file) {
+	FILE *f = rom_fopen(pnp_rom_file, "rb");
+	if (f) {
+		if (fread(sb->pnp_rom, 1, 512, f) == 512)
+			pnp_rom = sb->pnp_rom;
+		fclose(f);
+	}
+    }
+
+    switch (info->local) {
+	case 0:
+		isapnp_add_card(pnp_rom, sizeof(sb->pnp_rom), sb_16_pnp_config_changed, NULL, NULL, NULL, sb);
+		break;
+
+	case 1:
+		isapnp_add_card(pnp_rom, sizeof(sb->pnp_rom), sb_awe32_pnp_config_changed, NULL, NULL, NULL, sb);
+		break;
+
+	case 2:
+		isapnp_add_card(pnp_rom, sizeof(sb->pnp_rom), sb_awe64_gold_pnp_config_changed, NULL, NULL, NULL, sb);
+		break;
+    }
 
     return sb;
 }
@@ -2708,9 +2611,9 @@ const device_t sb_32_pnp_device =
 {
         "Sound Blaster 32 PnP",
         DEVICE_ISA | DEVICE_AT,
-	1,
+	0,
         sb_awe32_pnp_init, sb_awe32_close, NULL,
-        { sb_awe32_available },
+        { sb_32_pnp_available },
         sb_speed_changed,
         NULL,
         sb_32_pnp_config
@@ -2733,9 +2636,9 @@ const device_t sb_awe32_pnp_device =
 {
         "Sound Blaster AWE32 PnP",
         DEVICE_ISA | DEVICE_AT,
-	0,
+	1,
         sb_awe32_pnp_init, sb_awe32_close, NULL,
-        { sb_awe32_available },
+        { sb_awe32_pnp_available },
         sb_speed_changed,
         NULL,
         sb_awe32_pnp_config
@@ -2747,7 +2650,7 @@ const device_t sb_awe64_gold_device =
         DEVICE_ISA | DEVICE_AT,
 	2,
         sb_awe32_pnp_init, sb_awe32_close, NULL,
-        { sb_awe32_available },
+        { sb_awe64_gold_available },
         sb_speed_changed,
         NULL,
         sb_awe64_gold_config

From 3c997880717e2d0aeeb47cb81e03b9b41e04d20e Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 16:48:15 -0300
Subject: [PATCH 47/52] More UM8669F semantics stuff

---
 src/sio/sio_um8669f.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/sio/sio_um8669f.c b/src/sio/sio_um8669f.c
index 6fd2d1477..91b5c8d56 100644
--- a/src/sio/sio_um8669f.c
+++ b/src/sio/sio_um8669f.c
@@ -39,7 +39,7 @@
 #include <86box/isapnp.h>
 
 
-/* This ROM is reconstructed out of several assumptions, some of which are based on the IT8671F. */
+/* This ROM was reconstructed out of many assumptions, some of which based on the IT8671F. */
 static uint8_t um8669f_pnp_rom[] = {
     0x55, 0xa3, 0x86, 0x69, 0x00, 0x00, 0x00, 0x00, 0x00, /* UMC8669, dummy checksum (filled in by isapnp_add_card) */
     0x0a, 0x10, 0x10, /* PnP version 1.0, vendor version 1.0 */
@@ -151,8 +151,9 @@ um8669f_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *pri
 
 			fdc_set_irq(dev->fdc, config->irq[0].irq);
 			fdc_set_dma_ch(dev->fdc, (config->dma[0].dma == ISAPNP_DMA_DISABLED) ? -1 : config->dma[0].dma);
-		} else
+		} else {
 			um8669f_log("UM8669F: FDC disabled\n");
+		}
 
 		break;
 
@@ -163,8 +164,9 @@ um8669f_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *pri
 		if (config->activate && (config->io[0].base != ISAPNP_IO_DISABLED)) {
 			um8669f_log("UM8669F: UART %d enabled at port %04X IRQ %d\n", ld - 1, config->io[0].base, config->irq[0].irq);
 			serial_setup(dev->uart[ld - 1], config->io[0].base, config->irq[0].irq);
-		} else
+		} else {
 			um8669f_log("UM8669F: UART %d disabled\n", ld - 1);
+		}
 
 		break;
 
@@ -174,8 +176,9 @@ um8669f_pnp_config_changed(uint8_t ld, isapnp_device_config_t *config, void *pri
 		if (config->activate && (config->io[0].base != ISAPNP_IO_DISABLED)) {
 			um8669f_log("UM8669F: LPT enabled at port %04X IRQ %d\n", config->io[0].base, config->irq[0].irq);
 			lpt1_init(config->io[0].base);
-		} else
+		} else {
 			um8669f_log("UM8669F: LPT disabled\n");
+		}
 
 		break;
 

From 3babec62189ce34f13cdbee64473172d551748d3 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 20:28:03 -0300
Subject: [PATCH 48/52] Implement VIA AC97 clipping (not great atm)

---
 src/sound/snd_ac97_via.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index fd0f81c9d..72ff913f0 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -520,6 +520,15 @@ ac97_via_update(ac97_via_t *dev)
     int32_t l = (((dev->out_l * dev->pcm_vol_l) >> 15) * dev->master_vol_l) >> 15,
 	    r = (((dev->out_r * dev->pcm_vol_r) >> 15) * dev->master_vol_r) >> 15;
 
+    if (l < -32768)
+	l = -32768;
+    else if (l > 32767)
+	l = 32767;
+    if (r < -32768)
+	r = -32768;
+    else if (r > 32767)
+	r = 32767;
+
     for (; dev->pos < sound_pos_global; dev->pos++) {
 	dev->buffer[dev->pos*2]     = l;
 	dev->buffer[dev->pos*2 + 1] = r;

From e937de67605b1c68ba4aef73c55ca829aa95d825 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 20:28:24 -0300
Subject: [PATCH 49/52] Implement VIA SBPro emulation

---
 src/chipset/via_pipc.c | 107 ++++++++++++++++++++++++-----------------
 src/sound/snd_sb.c     |   1 -
 2 files changed, 63 insertions(+), 45 deletions(-)

diff --git a/src/chipset/via_pipc.c b/src/chipset/via_pipc.c
index 18c3296a1..f62775dc7 100644
--- a/src/chipset/via_pipc.c
+++ b/src/chipset/via_pipc.c
@@ -84,8 +84,7 @@ typedef struct
     acpi_t	*acpi;
     void	*gameport, *ac97;
     sb_t	*sb;
-    uint16_t	midigame_base, fmnmi_base;
-    uint8_t	fm_enabled;
+    uint16_t	midigame_base, sb_base, fmnmi_base;
 } pipc_t;
 
 
@@ -110,8 +109,8 @@ pipc_log(const char *fmt, ...)
 
 
 static void	pipc_sgd_handlers(pipc_t *dev, uint8_t modem);
-static void	pipc_midigame_handlers(pipc_t *dev, uint8_t modem);
 static void	pipc_codec_handlers(pipc_t *dev, uint8_t modem);
+static void	pipc_sb_handlers(pipc_t *dev, uint8_t modem);
 static uint8_t	pipc_read(int func, int addr, void *priv);
 static void	pipc_write(int func, int addr, uint8_t val, void *priv);
 
@@ -364,8 +363,8 @@ pipc_reset_hard(void *priv)
 		dev->ac97_regs[i][0x4b] = 0x02;
 
 		pipc_sgd_handlers(dev, i);
-		pipc_midigame_handlers(dev, i);
 		pipc_codec_handlers(dev, i);
+		pipc_sb_handlers(dev, i);
 	}
     }
 
@@ -471,33 +470,6 @@ pipc_sgd_handlers(pipc_t *dev, uint8_t modem)
 }
 
 
-static uint8_t
-pipc_midigame_read(uint16_t addr, void *priv)
-{
-    pipc_t *dev = (pipc_t *) priv;
-
-    /* This BAR apparently doesn't work at all on a real 686B. It doesn't react to writes,
-       and reads always return 0x80 or 0xff depending on AC97 audio register 0x42 bit 7. */
-    return (dev->ac97_regs[0][0x42] & 0x80) ? 0x80 : 0xff;
-}
-
-
-static void
-pipc_midigame_handlers(pipc_t *dev, uint8_t modem)
-{
-    if (!dev->ac97 || modem)
-	return;
-
-    if (dev->midigame_base)
-	io_removehandler(dev->midigame_base, 4, pipc_midigame_read, NULL, NULL, NULL, NULL, NULL, dev);
-
-    dev->midigame_base = (dev->ac97_regs[0][0x19] << 8) | (dev->ac97_regs[0][0x18] & 0xfc);
-
-    if (dev->midigame_base && (dev->ac97_regs[0][0x04] & PCI_COMMAND_IO))
-	io_sethandler(dev->midigame_base, 4, pipc_midigame_read, NULL, NULL, NULL, NULL, NULL, dev);
-}
-
-
 static void
 pipc_codec_handlers(pipc_t *dev, uint8_t modem)
 {
@@ -533,6 +505,22 @@ pipc_fmnmi_read(uint16_t addr, void *priv)
 }
 
 
+static void
+pipc_fmnmi_handlers(pipc_t *dev, uint8_t modem)
+{
+    if (!dev->ac97 || modem)
+	return;
+
+    if (dev->fmnmi_base)
+	io_removehandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, NULL, NULL, NULL, dev);
+
+    dev->fmnmi_base = (dev->ac97_regs[0][0x15] << 8) | (dev->ac97_regs[0][0x14] & 0xfc);
+
+    if (dev->fmnmi_base && (dev->ac97_regs[0][0x04] & PCI_COMMAND_IO))
+	io_sethandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, NULL, NULL, NULL, dev);
+}
+
+
 static uint8_t
 pipc_fm_read(uint16_t addr, void *priv)
 {
@@ -580,25 +568,53 @@ pipc_fm_write(uint16_t addr, uint8_t val, void *priv)
 
 
 static void
-pipc_fmnmi_handlers(pipc_t *dev, uint8_t modem)
+pipc_sb_handlers(pipc_t *dev, uint8_t modem)
 {
     if (!dev->ac97 || modem)
 	return;
 
-    if (dev->fmnmi_base)
-	io_removehandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, NULL, NULL, NULL, dev);
+    sb_dsp_setaddr(&dev->sb->dsp, 0);
+    if (dev->sb_base) {
+	io_removehandler(dev->sb_base,     4, opl3_read, NULL, NULL, opl3_write, NULL, NULL, &dev->sb->opl);
+	io_removehandler(dev->sb_base + 8, 2, opl3_read, NULL, NULL, opl3_write, NULL, NULL, &dev->sb->opl);
+	io_removehandler(dev->sb_base + 4, 2, sb_ct1345_mixer_read, NULL, NULL, sb_ct1345_mixer_write, NULL, NULL, dev->sb);
+    }
 
-    if (dev->fm_enabled)
-	io_removehandler(0x388, 4, pipc_fm_read, NULL, NULL, pipc_fm_write, NULL, NULL, dev);
+    mpu401_change_addr(dev->sb->mpu, 0);
+    mpu401_setirq(dev->sb->mpu, 0);
 
-    dev->fmnmi_base = (dev->ac97_regs[0][0x15] << 8) | (dev->ac97_regs[0][0x14] & 0xfc);
-    dev->fm_enabled = !!(dev->ac97_regs[0][0x42] & 0x04);
+    io_removehandler(0x388, 4, opl3_read, NULL, NULL, opl3_write, NULL, NULL, &dev->sb->opl);
 
-    if (dev->fmnmi_base && (dev->ac97_regs[0][0x04] & PCI_COMMAND_IO))
-	io_sethandler(dev->fmnmi_base, 4, pipc_fmnmi_read, NULL, NULL, NULL, NULL, NULL, dev);
+    if (dev->ac97_regs[0][0x42] & 0x01) {
+	dev->sb_base = 0x220 + (0x20 * (dev->ac97_regs[0][0x43] & 0x03));
+	sb_dsp_setaddr(&dev->sb->dsp, dev->sb_base);
+	if (dev->ac97_regs[0][0x42] & 0x04) {
+		io_sethandler(dev->sb_base,     4, opl3_read, NULL, NULL, opl3_write, NULL, NULL, &dev->sb->opl);
+		io_sethandler(dev->sb_base + 8, 2, opl3_read, NULL, NULL, opl3_write, NULL, NULL, &dev->sb->opl);
+	}
+	io_sethandler(dev->sb_base + 4, 2, sb_ct1345_mixer_read, NULL, NULL, sb_ct1345_mixer_write, NULL, NULL, dev->sb);
 
-    if (dev->fm_enabled)
+	uint8_t irq = 5 + (2 * ((dev->ac97_regs[0][0x43] >> 6) & 0x03));
+	sb_dsp_setirq(&dev->sb->dsp, (irq == 11) ? 10 : irq);
+
+	sb_dsp_setdma8(&dev->sb->dsp, (dev->ac97_regs[0][0x43] >> 4) & 0x03);
+    }
+
+    if (dev->ac97_regs[0][0x42] & 0x02) {
+	/* BAR 2 is a mess. The MPU and game port remapping registers that VIA claims to be there don't
+	   seem to actually exist on a real 686B. Remapping the MPU to BAR 2 itself does work, though. */
+	if (dev->ac97_regs[0][0x42] & 0x80)
+		mpu401_change_addr(dev->sb->mpu, (dev->ac97_regs[0][0x19] << 8) | (dev->ac97_regs[0][0x18] & 0xfc));
+	else
+		mpu401_change_addr(dev->sb->mpu, 0x300 | ((dev->ac97_regs[0][0x43] << 2) & 0x30));
+
+        if (!(dev->ac97_regs[0][0x42] & 0x40))
+		mpu401_setirq(dev->sb->mpu, dev->sb->dsp.sb_irqnum);
+    }
+
+    if (dev->ac97_regs[0][0x42] & 0x04) {
 	io_sethandler(0x388, 4, pipc_fm_read, NULL, NULL, pipc_fm_write, NULL, NULL, dev);
+    }
 }
 
 
@@ -1170,7 +1186,6 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 	switch (addr) {
 		case 0x04:
 			dev->ac97_regs[func][addr] = val;
-			pipc_midigame_handlers(dev, func);
 			pipc_sgd_handlers(dev, func);
 			pipc_codec_handlers(dev, func);
 			pipc_fmnmi_handlers(dev, func);
@@ -1197,7 +1212,7 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			if (addr == 0x18)
 				val = (val & 0xfc) | 1;
 			dev->ac97_regs[func][addr] = val;
-			pipc_midigame_handlers(dev, func);
+			pipc_sb_handlers(dev, func);
 			break;
 
 		case 0x1c: case 0x1d:
@@ -1219,7 +1234,7 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			dev->ac97_regs[0][addr] = dev->ac97_regs[1][addr] = val;
 			gameport_remap(dev->gameport, (dev->ac97_regs[0][0x42] & 0x08) ? ((dev->ac97_regs[0][0x4b] << 8) | (dev->ac97_regs[0][0x4a] & 0xf8)) : 0);
 			if (addr == 0x42)
-				pipc_fmnmi_handlers(dev, func);
+				pipc_sb_handlers(dev, func);
 			break;
 
 		case 0x43:
@@ -1316,6 +1331,10 @@ pipc_init(const device_t *info)
 	ac97_via_set_slot(dev->ac97, dev->slot, PCI_INTC);
 
 	dev->sb = device_add(&sb_pro_compat_device);
+#ifndef VIA_PIPC_FM_EMULATION
+	dev->sb->opl_enabled = 1;
+#endif
+	sound_add_handler(sb_get_buffer_sbpro, dev->sb);
 
 	dev->gameport = gameport_add(&gameport_sio_device);
     }
diff --git a/src/sound/snd_sb.c b/src/sound/snd_sb.c
index 287de664e..24d3dc2af 100644
--- a/src/sound/snd_sb.c
+++ b/src/sound/snd_sb.c
@@ -1571,7 +1571,6 @@ sb_pro_compat_init(const device_t *info)
     sb_t *sb = malloc(sizeof(sb_t));
     memset(sb, 0, sizeof(sb_t));
 
-    sb->opl_enabled = 0; /* CS423x updates this, while VT82C686 lacks OPL */
     opl3_init(&sb->opl);
 
     sb_dsp_init(&sb->dsp, SBPRO2, SB_SUBTYPE_DEFAULT, sb);

From b0c1e4726fd9b33c47ad1a9e2c1da8d34632743e Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 21:24:08 -0300
Subject: [PATCH 50/52] VIA AC97: Fix SGD pause bit, fixes mpxplay looping on
 stop

---
 src/sound/snd_ac97_via.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 72ff913f0..18abf8a90 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -350,10 +350,10 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 			if (val & 0x40)
 				dev->sgd_regs[addr & 0xf0] &= ~0x88;
 
-			val &= 0x04;
+			val &= 0x08;
 
 			/* (Un)pause SGD if requested. */
-			if (val & 0x04)
+			if (val & 0x08)
 				dev->sgd_regs[addr & 0xf0] |= 0x40;
 			else
 				dev->sgd_regs[addr & 0xf0] &= ~0x40;

From 61784ca9f49e02f23443779aee0efbcef6e1a917 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Tue, 3 Aug 2021 21:36:20 -0300
Subject: [PATCH 51/52] VIA AC97: Remove status register workaround, fixed by
 the SGD pause bit fix

---
 src/sound/snd_ac97_via.c | 14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index 18abf8a90..a09af6575 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -37,7 +37,7 @@ typedef struct {
 
     uint32_t	entry_ptr, sample_ptr, fifo_pos, fifo_end;
     int32_t	sample_count;
-    uint8_t	entry_flags, fifo[32], restart, status_shadow;
+    uint8_t	entry_flags, fifo[32], restart;
 
     pc_timer_t	timer;
 } ac97_via_sgd_t;
@@ -203,10 +203,6 @@ ac97_via_sgd_read(uint16_t addr, void *priv)
     if (!(addr & 0x80)) {
 	/* Process SGD channel registers. */
 	switch (addr & 0xf) {
-		case 0x0:
-			ret = dev->sgd[addr >> 4].status_shadow;
-			break;
-
 		case 0x4:
 			ret = dev->sgd[addr >> 4].entry_ptr;
 			break;
@@ -239,9 +235,6 @@ ac97_via_sgd_read(uint16_t addr, void *priv)
 			ret = dev->sgd_regs[addr];
 			break;
 	}
-
-	/* Reset SGD status shadow register. See comment on SGD register 0x0 write for more information. */
-	dev->sgd[addr >> 4].status_shadow = dev->sgd_regs[addr & 0xf0];
     } else {
 	/* Process regular registers. */
 	switch (addr) {
@@ -319,11 +312,6 @@ ac97_via_sgd_write(uint16_t addr, uint8_t val, void *priv)
 			/* Update status interrupts. */
 			ac97_via_update_irqs(dev);
 
-			/* Work around a race condition with the V7.00b WDM driver expecting SGD Active to
-			   not clear immediately. It reads this register next, so set up a shadow register
-			   to ensure SGD Active is set for that specific read (but not subsequent ones). */
-			dev->sgd[addr >> 4].status_shadow = dev->sgd_regs[addr] | 0x80;
-
 			return;
 
 		case 0x1:

From 6ee927458284652fb0692d305bc2c2cf3bb4aec0 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Wed, 4 Aug 2021 01:00:44 -0300
Subject: [PATCH 52/52] VIA AC97: Change FM data format after an exhaustive
 probe

---
 src/sound/snd_ac97_via.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/sound/snd_ac97_via.c b/src/sound/snd_ac97_via.c
index a09af6575..1707c0c9a 100644
--- a/src/sound/snd_ac97_via.c
+++ b/src/sound/snd_ac97_via.c
@@ -57,7 +57,7 @@ typedef struct _ac97_via_ {
     ac97_via_sgd_t sgd[6];
 
     pc_timer_t	timer_count, timer_count_fm;
-    uint64_t	timer_latch;
+    uint64_t	timer_latch, timer_latch_fm;
     int16_t	out_l, out_r, fm_out_l, fm_out_r;
     int		master_vol_l, master_vol_r, pcm_vol_l, pcm_vol_r, cd_vol_l, cd_vol_r;
     int32_t	buffer[SOUNDBUFLEN * 2], fm_buffer[SOUNDBUFLEN * 2];
@@ -713,16 +713,18 @@ ac97_via_poll_fm(void *priv)
 
     /* Schedule next run if FM playback is enabled. */
     if (dev->fm_enabled)
-	timer_advance_u64(&dev->timer_count_fm, dev->timer_latch);
+	timer_advance_u64(&dev->timer_count_fm, dev->timer_latch_fm);
 
     /* Update FM audio buffer. */
     ac97_via_update_fm(dev);
 
     /* Feed next sample from the FIFO.
-       Unknown data format assumed to be 8-bit stereo. */
-    if ((sgd->fifo_end - sgd->fifo_pos) >= 2) {
-	dev->fm_out_l = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
-	dev->fm_out_r = (sgd->fifo[sgd->fifo_pos++ & (sizeof(sgd->fifo) - 1)] ^ 0x80) << 8;
+       The data format is not documented, but it probes as 16-bit stereo at 24 KHz. */
+    if ((sgd->fifo_end - sgd->fifo_pos) >= 4) {
+	dev->out_l = *((uint16_t *) &sgd->fifo[sgd->fifo_pos & (sizeof(sgd->fifo) - 1)]);
+	sgd->fifo_pos += 2;
+	dev->out_r = *((uint16_t *) &sgd->fifo[sgd->fifo_pos & (sizeof(sgd->fifo) - 1)]);
+	sgd->fifo_pos += 2;
 	return;
     }
 
@@ -772,6 +774,7 @@ ac97_via_speed_changed(void *priv)
 	freq = 48000.0;
 
     dev->timer_latch = (uint64_t) ((double) TIMER_USEC * (1000000.0 / freq));
+    dev->timer_latch_fm = (uint64_t) ((double) TIMER_USEC * (1000000.0 / 24000.0));
 }