Files
86Box/src/chipset/opti495.c
Jasmine Iwanek 4e6f29a7d5 malloc to calloc
2025-02-01 15:38:36 -05:00

292 lines
7.9 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 OPTi 82C493/82C495 chipset.
*
*
*
* Authors: Tiseno100,
* Miran Grca, <mgrca8@gmail.com>
*
* Copyright 2008-2020 Tiseno100.
* Copyright 2016-2020 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/io.h>
#include <86box/device.h>
#include <86box/mem.h>
#include <86box/port_92.h>
#include <86box/chipset.h>
typedef struct opti495_t {
uint8_t type;
uint8_t max;
uint8_t idx;
uint8_t regs[256];
uint8_t scratch[2];
} opti495_t;
#ifdef ENABLE_OPTI495_LOG
int opti495_do_log = ENABLE_OPTI495_LOG;
static void
opti495_log(const char *fmt, ...)
{
va_list ap;
if (opti495_do_log) {
va_start(ap, fmt);
pclog_ex(fmt, ap);
va_end(ap);
}
}
#else
# define opti495_log(fmt, ...)
#endif
enum {
OPTI493 = 0,
OPTI495,
OPTI495SLC,
OPTI495SX,
OPTI495XLC,
TMAX
};
/* OPTi 82C493: According to The Last Byte, bit 1 of register 22h, while unused, must still be writable. */
static uint8_t masks[TMAX][0x1c] = { { 0x3f, 0xff, 0xff, 0xff, 0xf7, 0xfb, 0x7f, 0x9f, 0xe3, 0xff, 0xe3, 0xff },
{ 0x3a, 0x7f, 0xff, 0xff, 0xf0, 0xfb, 0x7f, 0xbf, 0xe3, 0xff, 0x00, 0x00 },
{ 0x3a, 0x7f, 0xfc, 0xff, 0xf0, 0xfb, 0xff, 0xbf, 0xe3, 0xff, 0x00, 0x00 },
{ 0x3a, 0xff, 0xfd, 0xff, 0xf0, 0xfb, 0x7f, 0xbf, 0xe3, 0xff, 0x00, 0x00 },
{ 0x3a, 0xff, 0xfc, 0xff, 0xf0, 0xfb, 0xff, 0xbf, 0xe3, 0xff, 0x00, 0x00 } };
static void
opti495_recalc(opti495_t *dev)
{
uint32_t base;
uint32_t shflags = 0;
shadowbios = 0;
shadowbios_write = 0;
if (dev->regs[0x22] & 0x80) {
shadowbios = 1;
shadowbios_write = 0;
shflags = MEM_READ_EXTANY | MEM_WRITE_INTERNAL;
} else {
shadowbios = 0;
shadowbios_write = 1;
shflags = MEM_READ_INTERNAL | MEM_WRITE_DISABLED;
}
mem_set_mem_state_both(0xf0000, 0x10000, shflags);
for (uint8_t i = 0; i < 8; i++) {
base = 0xd0000 + (i << 14);
if ((dev->regs[0x22] & ((base >= 0xe0000) ? 0x20 : 0x40)) && (dev->regs[0x23] & (1 << i))) {
shflags = MEM_READ_INTERNAL;
shflags |= (dev->regs[0x22] & ((base >= 0xe0000) ? 0x08 : 0x10)) ? MEM_WRITE_DISABLED : MEM_WRITE_INTERNAL;
} else {
if (dev->regs[0x26] & 0x40) {
shflags = MEM_READ_EXTANY;
shflags |= (dev->regs[0x22] & ((base >= 0xe0000) ? 0x08 : 0x10)) ? MEM_WRITE_DISABLED : MEM_WRITE_INTERNAL;
} else
shflags = MEM_READ_EXTANY | MEM_WRITE_EXTANY;
}
mem_set_mem_state_both(base, 0x4000, shflags);
}
for (uint8_t i = 0; i < 4; i++) {
base = 0xc0000 + (i << 14);
if ((dev->regs[0x26] & 0x10) && (dev->regs[0x26] & (1 << i))) {
shflags = MEM_READ_INTERNAL;
shflags |= (dev->regs[0x26] & 0x20) ? MEM_WRITE_DISABLED : MEM_WRITE_INTERNAL;
} else {
if (dev->regs[0x26] & 0x40) {
shflags = MEM_READ_EXTANY;
shflags |= (dev->regs[0x26] & 0x20) ? MEM_WRITE_DISABLED : MEM_WRITE_INTERNAL;
} else
shflags = MEM_READ_EXTANY | MEM_WRITE_EXTANY;
}
mem_set_mem_state_both(base, 0x4000, shflags);
}
flushmmucache();
}
static void
opti495_write(uint16_t addr, uint8_t val, void *priv)
{
opti495_t *dev = (opti495_t *) priv;
switch (addr) {
default:
break;
case 0x22:
opti495_log("[%04X:%08X] [W] dev->idx = %02X\n", CS, cpu_state.pc, val);
dev->idx = val;
break;
case 0x24:
if ((dev->idx >= 0x20) && (dev->idx <= dev->max)) {
opti495_log("[%04X:%08X] [W] dev->regs[%04X] = %02X\n", CS, cpu_state.pc, dev->idx, val);
dev->regs[dev->idx] = val & masks[dev->type][dev->idx - 0x20];
if ((dev->type == OPTI493) && (dev->idx == 0x20))
val |= 0x40;
switch (dev->idx) {
default:
break;
case 0x21:
cpu_cache_ext_enabled = !!(dev->regs[0x21] & 0x10);
cpu_update_waitstates();
break;
case 0x22:
case 0x23:
case 0x26:
opti495_recalc(dev);
break;
}
}
dev->idx = 0xff;
break;
case 0xe1:
case 0xe2:
dev->scratch[~addr & 0x01] = val;
break;
}
}
static uint8_t
opti495_read(uint16_t addr, void *priv)
{
uint8_t ret = 0xff;
opti495_t *dev = (opti495_t *) priv;
switch (addr) {
case 0x22:
opti495_log("[%04X:%08X] [R] dev->idx = %02X\n", CS, cpu_state.pc, ret);
break;
case 0x24:
if ((dev->idx >= 0x20) && (dev->idx <= dev->max)) {
ret = dev->regs[dev->idx];
opti495_log("[%04X:%08X] [R] dev->regs[%04X] = %02X\n", CS, cpu_state.pc, dev->idx, ret);
}
dev->idx = 0xff;
break;
case 0xe1:
case 0xe2:
ret = dev->scratch[~addr & 0x01];
break;
default:
break;
}
return ret;
}
static void
opti495_close(void *priv)
{
opti495_t *dev = (opti495_t *) priv;
free(dev);
}
static void *
opti495_init(const device_t *info)
{
opti495_t *dev = (opti495_t *) calloc(1, sizeof(opti495_t));
device_add(&port_92_device);
io_sethandler(0x0022, 0x0001, opti495_read, NULL, NULL, opti495_write, NULL, NULL, dev);
io_sethandler(0x0024, 0x0001, opti495_read, NULL, NULL, opti495_write, NULL, NULL, dev);
dev->scratch[0] = dev->scratch[1] = 0xff;
dev->type = info->local;
if (info->local >= OPTI495) {
/* 85C495 */
dev->max = 0x29;
dev->regs[0x20] = 0x02;
dev->regs[0x21] = 0x20;
dev->regs[0x22] = 0xe4;
dev->regs[0x25] = 0xf0;
dev->regs[0x26] = 0x80;
dev->regs[0x27] = 0xb1;
dev->regs[0x28] = 0x80;
dev->regs[0x29] = 0x10;
} else {
/* 85C493 */
dev->max = 0x2b;
dev->regs[0x20] = 0x40;
dev->regs[0x22] = 0x84;
dev->regs[0x24] = 0x87;
dev->regs[0x25] = 0xf1; /* Note: 0xf0 is also valid default. */
dev->regs[0x27] = 0x91;
dev->regs[0x28] = 0x80;
dev->regs[0x29] = 0x10;
dev->regs[0x2a] = 0x80;
dev->regs[0x2b] = 0x10;
}
opti495_recalc(dev);
io_sethandler(0x00e1, 0x0002, opti495_read, NULL, NULL, opti495_write, NULL, NULL, dev);
return dev;
}
const device_t opti493_device = {
.name = "OPTi 82C493",
.internal_name = "opti493",
.flags = 0,
.local = OPTI493,
.init = opti495_init,
.close = opti495_close,
.reset = NULL,
.available = NULL,
.speed_changed = NULL,
.force_redraw = NULL,
.config = NULL
};
const device_t opti495_device = {
.name = "OPTi 82C495",
.internal_name = "opti495",
.flags = 0,
.local = OPTI495XLC,
.init = opti495_init,
.close = opti495_close,
.reset = NULL,
.available = NULL,
.speed_changed = NULL,
.force_redraw = NULL,
.config = NULL
};