Files
86Box/src/chipset/umc_8886.c
2021-04-29 19:57:50 +02:00

301 lines
6.2 KiB
C

/*
* 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.
*
* Implementation of the UMC 8886xx PCI to ISA Bridge .
*
* Note: This chipset has no datasheet, everything were done via
* reverse engineering the BIOS of various machines using it.
*
* Authors: Tiseno100,
*
* Copyright 2021 Tiseno100.
*/
/* UMC 8886 Configuration Registers
TODO:
- More Appropriate Bitmasking(If it's even possible)
Warning: Register documentation may be inaccurate!
UMC 8886xx:
(F: Has No Internal IDE / AF or BF: Has Internal IDE)
Function 0 Register 43:
Bits 7-4 PCI IRQ for INTB
Bits 3-0 PCI IRQ for INTA
Function 0 Register 44:
Bits 7-4 PCI IRQ for INTD
Bits 3-0 PCI IRQ for INTC
Function 0 Register 46:
Bit 7: Replace SMI request for non-SMM CPU's (1: IRQ15/0: IRQ10)
Function 0 Register 51:
Bit 2: VGA Power Down (0: Standard/1: VESA DPMS)
Function 0 Register 56:
Bit 1-0 ISA Bus Speed
0 0 PCICLK/3
0 1 PCICLK/4
1 0 PCICLK/2
Function 0 Register A4:
Bit 0: Host to PCI Clock (1: 1 by 1/0: 1 by half)
Function 1 Register 4:
Bit 0: Enable Internal IDE
*/
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#define HAVE_STDARG_H
#include <86box/86box.h>
#include "cpu.h"
#include <86box/timer.h>
#include <86box/io.h>
#include <86box/device.h>
#include <86box/hdd.h>
#include <86box/hdc.h>
#include <86box/hdc_ide.h>
#include <86box/pci.h>
#include <86box/chipset.h>
#ifdef ENABLE_UMC_8886_LOG
int umc_8886_do_log = ENABLE_UMC_8886_LOG;
static void
umc_8886_log(const char *fmt, ...)
{
va_list ap;
if (umc_8886_do_log)
{
va_start(ap, fmt);
pclog_ex(fmt, ap);
va_end(ap);
}
}
#else
#define umc_8886_log(fmt, ...)
#endif
/* PCI IRQ Flags */
#define INTA (PCI_INTA + (2 * !(addr & 1)))
#define INTB (PCI_INTB + (2 * !(addr & 1)))
#define IRQRECALCA (((val & 0xf0) != 0) ? ((val & 0xf0) >> 4) : PCI_IRQ_DISABLED)
#define IRQRECALCB (((val & 0x0f) != 0) ? (val & 0x0f) : PCI_IRQ_DISABLED)
/* Disable Internal IDE Flag needed for the BF Southbridge variant */
#define HAS_IDE dev->has_ide
/* Southbridge Revision */
#define SB_ID dev->sb_id
typedef struct umc_8886_t
{
uint8_t pci_conf_sb[2][256]; /* PCI Registers */
uint16_t sb_id; /* Southbridge Revision */
int has_ide; /* Check if Southbridge Revision is AF or F */
} umc_8886_t;
static void
umc_8886_ide_handler(int status)
{
ide_pri_disable();
ide_sec_disable();
if (status) {
ide_pri_enable();
ide_sec_enable();
}
}
static void
um8886_write(int func, int addr, uint8_t val, void *priv)
{
umc_8886_t *dev = (umc_8886_t *)priv;
umc_8886_log("UM8886: dev->regs[%02x] = %02x (%02x)\n", addr, val, func);
/* We don't know the RW status of registers but Phoenix writes on some RO registers too*/
if (addr > 3) switch (func) {
case 0: /* Southbridge */
switch (addr) {
case 0x43:
case 0x44:
dev->pci_conf_sb[func][addr] = val;
pci_set_irq_routing(INTA, IRQRECALCA);
pci_set_irq_routing(INTB, IRQRECALCB);
break;
case 0x46:
dev->pci_conf_sb[func][addr] = val & 0xaf;
break;
case 0x47:
dev->pci_conf_sb[func][addr] = val & 0x4f;
break;
case 0x56:
dev->pci_conf_sb[func][addr] = val;
switch (val & 2) {
case 0:
cpu_set_isa_pci_div(3);
break;
case 1:
cpu_set_isa_pci_div(4);
break;
case 2:
cpu_set_isa_pci_div(2);
break;
}
break;
case 0x57:
dev->pci_conf_sb[func][addr] = val & 0x38;
break;
case 0x71:
dev->pci_conf_sb[func][addr] = val & 1;
break;
case 0x90:
dev->pci_conf_sb[func][addr] = val & 2;
break;
case 0x92:
dev->pci_conf_sb[func][addr] = val & 0x1f;
break;
case 0xa0:
dev->pci_conf_sb[func][addr] = val & 0xfc;
break;
case 0xa4:
dev->pci_conf_sb[func][addr] = val & 0x89;
cpu_set_pci_speed(cpu_busspeed / ((val & 1) ? 1 : 2));
break;
default:
dev->pci_conf_sb[func][addr] = val;
break;
}
break;
case 1: /* IDE Controller */
dev->pci_conf_sb[func][addr] = val;
if ((addr == 4) && HAS_IDE)
umc_8886_ide_handler(val & 1);
break;
}
}
static uint8_t
um8886_read(int func, int addr, void *priv)
{
umc_8886_t *dev = (umc_8886_t *)priv;
return dev->pci_conf_sb[func][addr];
}
static void
umc_8886_reset(void *priv)
{
umc_8886_t *dev = (umc_8886_t *)priv;
/* Defaults */
dev->pci_conf_sb[0][0] = 0x60; /* UMC */
dev->pci_conf_sb[0][1] = 0x10;
dev->pci_conf_sb[0][2] = (SB_ID & 0xff); /* 8886xx */
dev->pci_conf_sb[0][3] = ((SB_ID >> 8) & 0xff);
dev->pci_conf_sb[0][8] = 1;
dev->pci_conf_sb[0][0x09] = 0x00;
dev->pci_conf_sb[0][0x0a] = 0x01;
dev->pci_conf_sb[0][0x0b] = 0x06;
for (int i = 1; i < 5; i++) /* Disable all IRQ interrupts */
pci_set_irq_routing(i, PCI_IRQ_DISABLED);
if (HAS_IDE) {
dev->pci_conf_sb[1][4] = 1; /* Start with Internal IDE Enabled */
umc_8886_ide_handler(1);
}
}
static void
umc_8886_close(void *priv)
{
umc_8886_t *dev = (umc_8886_t *)priv;
free(dev);
}
static void *
umc_8886_init(const device_t *info)
{
umc_8886_t *dev = (umc_8886_t *)malloc(sizeof(umc_8886_t));
memset(dev, 0, sizeof(umc_8886_t));
dev->has_ide = (info->local == 0x886a);
pci_add_card(PCI_ADD_SOUTHBRIDGE, um8886_read, um8886_write, dev); /* Device 12: UMC 8886xx */
/* Add IDE if UM8886AF variant */
if (HAS_IDE)
device_add(&ide_pci_2ch_device);
/* Get the Southbridge Revision */
SB_ID = info->local;
umc_8886_reset(dev);
return dev;
}
const device_t umc_8886f_device = {
"UMC 8886F",
DEVICE_PCI,
0x8886,
umc_8886_init,
umc_8886_close,
umc_8886_reset,
{ NULL },
NULL,
NULL,
NULL
};
const device_t umc_8886af_device = {
"UMC 8886AF",
DEVICE_PCI,
0x886a,
umc_8886_init,
umc_8886_close,
umc_8886_reset,
{ NULL },
NULL,
NULL,
NULL
};