Files
86Box/src/chipset/contaq_82c59x.c

381 lines
11 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 Contaq/Cypress 82C596(A) and 597 chipsets.
*
*
*
* Authors: Miran Grca, <mgrca8@gmail.com>
*
* Copyright 2021 Miran Grca.
*/
#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/mem.h>
#include <86box/smram.h>
#include <86box/chipset.h>
#ifdef ENABLE_CONTAQ_82C59X_LOG
int contaq_82c59x_do_log = ENABLE_CONTAQ_82C59X_LOG;
static void
contaq_82c59x_log(const char *fmt, ...)
{
va_list ap;
if (contaq_82c59x_do_log) {
va_start(ap, fmt);
pclog_ex(fmt, ap);
va_end(ap);
}
}
#else
# define contaq_82c59x_log(fmt, ...)
#endif
typedef struct mem_remapping_t {
uint32_t phys;
uint32_t virt;
} mem_remapping_t;
typedef struct contaq_82c59x_t {
uint8_t index;
uint8_t green;
uint8_t smi_status_set;
uint8_t regs[256];
uint8_t smi_status[2];
smram_t *smram[2];
} contaq_82c59x_t;
static void
contaq_82c59x_isa_speed_recalc(contaq_82c59x_t *dev)
{
if (dev->regs[0x1c] & 0x02)
cpu_set_isa_speed(7159091);
else {
/* TODO: ISA clock dividers for 386 and alt. 486. */
switch (dev->regs[0x10] & 0x03) {
case 0x00:
cpu_set_isa_speed(cpu_busspeed / 4);
break;
case 0x01:
cpu_set_isa_speed(cpu_busspeed / 6);
break;
case 0x02:
cpu_set_isa_speed(cpu_busspeed / 8);
break;
case 0x03:
cpu_set_isa_speed(cpu_busspeed / 5);
break;
default:
break;
}
}
}
static void
contaq_82c59x_shadow_recalc(contaq_82c59x_t *dev)
{
uint32_t i;
uint32_t base;
uint8_t bit;
shadowbios = shadowbios_write = 0;
/* F0000-FFFFF */
if (dev->regs[0x15] & 0x80) {
shadowbios |= 1;
mem_set_mem_state_both(0xf0000, 0x10000, MEM_READ_INTERNAL | MEM_WRITE_EXTANY);
} else {
shadowbios_write |= 1;
mem_set_mem_state_both(0xf0000, 0x10000, MEM_READ_EXTANY | MEM_WRITE_INTERNAL);
}
/* C0000-CFFFF */
if (dev->regs[0x15] & 0x01)
mem_set_mem_state_both(0xc0000, 0x10000, MEM_READ_EXTANY | MEM_WRITE_EXTANY);
else {
for (i = 0; i < 4; i++) {
base = 0xc0000 + (i << 14);
bit = 1 << (i + 2);
if (dev->regs[0x15] & bit) {
if (dev->regs[0x15] & 0x02)
mem_set_mem_state_both(base, 0x04000, MEM_READ_INTERNAL | MEM_WRITE_EXTERNAL);
else
mem_set_mem_state_both(base, 0x04000, MEM_READ_EXTERNAL | MEM_WRITE_INTERNAL);
} else
mem_set_mem_state_both(base, 0x04000, MEM_READ_EXTERNAL | MEM_WRITE_EXTERNAL);
}
}
if (dev->green) {
/* D0000-DFFFF */
if (dev->regs[0x6e] & 0x01)
mem_set_mem_state_both(0xd0000, 0x10000, MEM_READ_EXTANY | MEM_WRITE_EXTANY);
else {
for (i = 0; i < 4; i++) {
base = 0xd0000 + (i << 14);
bit = 1 << (i + 2);
if (dev->regs[0x6e] & bit) {
if (dev->regs[0x6e] & 0x02)
mem_set_mem_state_both(base, 0x04000, MEM_READ_INTERNAL | MEM_WRITE_EXTERNAL);
else
mem_set_mem_state_both(base, 0x04000, MEM_READ_INTERNAL | MEM_WRITE_INTERNAL);
} else
mem_set_mem_state_both(base, 0x04000, MEM_READ_EXTERNAL | MEM_WRITE_EXTERNAL);
}
}
/* E0000-EFFFF */
if (dev->regs[0x6f] & 0x01)
mem_set_mem_state_both(0xe0000, 0x10000, MEM_READ_EXTANY | MEM_WRITE_EXTANY);
else {
for (i = 0; i < 4; i++) {
base = 0xe0000 + (i << 14);
bit = 1 << (i + 2);
if (dev->regs[0x6f] & bit) {
shadowbios |= 1;
if (dev->regs[0x6f] & 0x02)
mem_set_mem_state_both(base, 0x04000, MEM_READ_INTERNAL | MEM_WRITE_EXTERNAL);
else {
shadowbios_write |= 1;
mem_set_mem_state_both(base, 0x04000, MEM_READ_INTERNAL | MEM_WRITE_INTERNAL);
}
} else
mem_set_mem_state_both(base, 0x04000, MEM_READ_EXTERNAL | MEM_WRITE_EXTERNAL);
}
}
}
}
static void
contaq_82c59x_smram_recalc(contaq_82c59x_t *dev)
{
smram_disable(dev->smram[1]);
if (dev->regs[0x70] & 0x04)
smram_enable(dev->smram[1], 0x00040000, 0x000a0000, 0x00020000, 1, 1);
}
static void
contaq_82c59x_write(uint16_t addr, uint8_t val, void *priv)
{
contaq_82c59x_t *dev = (contaq_82c59x_t *) priv;
switch (addr) {
case 0x22:
dev->index = val;
break;
case 0x23:
contaq_82c59x_log("Contaq 82C59x: dev->regs[%02x] = %02x\n", dev->index, val);
if ((dev->index >= 0x60) && !dev->green)
return;
switch (dev->index) {
/* Registers common to 82C596(A) and 82C597. */
case 0x10:
dev->regs[dev->index] = val;
contaq_82c59x_isa_speed_recalc(dev);
break;
case 0x11:
dev->regs[dev->index] = val;
cpu_cache_int_enabled = !!(val & 0x01);
cpu_update_waitstates();
break;
case 0x12:
case 0x13:
dev->regs[dev->index] = val;
break;
case 0x14:
dev->regs[dev->index] = val;
reset_on_hlt = !!(val & 0x80);
break;
case 0x15:
dev->regs[dev->index] = val;
contaq_82c59x_shadow_recalc(dev);
break;
case 0x16 ... 0x1b:
dev->regs[dev->index] = val;
break;
case 0x1c:
/* TODO: What's NPRST (generated if bit 3 is set)? */
dev->regs[dev->index] = val;
contaq_82c59x_isa_speed_recalc(dev);
break;
case 0x1d ... 0x1f:
dev->regs[dev->index] = val;
break;
/* Green (82C597-specific) registers. */
case 0x60 ... 0x63:
dev->regs[dev->index] = val;
break;
case 0x64:
dev->regs[dev->index] = val;
if (val & 0x80) {
if (dev->regs[0x65] & 0x80)
smi_raise();
dev->smi_status[0] |= 0x10;
}
break;
case 0x65 ... 0x69:
dev->regs[dev->index] = val;
break;
case 0x6a:
dev->regs[dev->index] = val;
dev->smi_status_set = !!(val & 0x80);
break;
case 0x6b ... 0x6d:
dev->regs[dev->index] = val;
break;
case 0x6e:
case 0x6f:
dev->regs[dev->index] = val;
contaq_82c59x_shadow_recalc(dev);
break;
case 0x70:
dev->regs[dev->index] = val;
contaq_82c59x_smram_recalc(dev);
break;
case 0x71 ... 0x79:
dev->regs[dev->index] = val;
break;
case 0x7b:
case 0x7c:
dev->regs[dev->index] = val;
break;
default:
break;
}
break;
default:
break;
}
}
static uint8_t
contaq_82c59x_read(uint16_t addr, void *priv)
{
contaq_82c59x_t *dev = (contaq_82c59x_t *) priv;
uint8_t ret = 0xff;
if (addr == 0x23) {
if (dev->index == 0x6a) {
ret = dev->smi_status[dev->smi_status_set];
/* I assume it's cleared on read. */
dev->smi_status[dev->smi_status_set] = 0x00;
} else
ret = dev->regs[dev->index];
}
return ret;
}
static void
contaq_82c59x_close(void *priv)
{
contaq_82c59x_t *dev = (contaq_82c59x_t *) priv;
if (dev->green) {
smram_del(dev->smram[1]);
smram_del(dev->smram[0]);
}
free(dev);
}
static void *
contaq_82c59x_init(const device_t *info)
{
contaq_82c59x_t *dev = (contaq_82c59x_t *) malloc(sizeof(contaq_82c59x_t));
memset(dev, 0x00, sizeof(contaq_82c59x_t));
dev->green = info->local;
io_sethandler(0x0022, 0x0002, contaq_82c59x_read, NULL, NULL, contaq_82c59x_write, NULL, NULL, dev);
contaq_82c59x_isa_speed_recalc(dev);
cpu_cache_int_enabled = 0;
cpu_update_waitstates();
reset_on_hlt = 0;
contaq_82c59x_shadow_recalc(dev);
if (dev->green) {
/* SMRAM 0: Fixed A0000-BFFFF to A0000-BFFFF DRAM. */
dev->smram[0] = smram_add();
smram_enable(dev->smram[0], 0x000a0000, 0x000a0000, 0x00020000, 0, 1);
/* SMRAM 1: Optional. */
dev->smram[1] = smram_add();
contaq_82c59x_smram_recalc(dev);
}
return dev;
}
const device_t contaq_82c596a_device = {
.name = "Contaq 82C596A",
.internal_name = "contaq_82c596a",
.flags = 0,
.local = 0,
.init = contaq_82c59x_init,
.close = contaq_82c59x_close,
.reset = NULL,
{ .available = NULL },
.speed_changed = NULL,
.force_redraw = NULL,
.config = NULL
};
const device_t contaq_82c597_device = {
.name = "Contaq 82C597",
.internal_name = "contaq_82c597",
.flags = 0,
.local = 1,
.init = contaq_82c59x_init,
.close = contaq_82c59x_close,
.reset = NULL,
{ .available = NULL },
.speed_changed = NULL,
.force_redraw = NULL,
.config = NULL
};