Files
86Box/src/chipset/opti5x7.c

156 lines
3.7 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 82C546/82C547 & 82C596/82C597 chipsets.
* Authors: plant/nerd73
* Miran Grca, <mgrca8@gmail.com>
*
* Copyright 2020 plant/nerd73.
* Copyright 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/timer.h>
#include <86box/io.h>
#include <86box/device.h>
#include <86box/keyboard.h>
#include <86box/mem.h>
#include <86box/fdd.h>
#include <86box/fdc.h>
#include <86box/port_92.h>
#include <86box/chipset.h>
typedef struct
{
uint8_t idx,
regs[16];
port_92_t *port_92;
} opti5x7_t;
static void
opti5x7_recalc(opti5x7_t *dev)
{
uint32_t base;
uint32_t i, j, shflags = 0;
uint32_t reg, lowest_bit;
uint32_t write = 0;
for (i = 0; i < 8; i++) {
j = i / 2.01; /*Probably not a great way of doing this, but it does work*/
base = 0xc0000 + (j << 14);
lowest_bit = j * 2;
reg = 0x04 + ((base >> 16) & 0x01);
shflags = (dev->regs[reg] & (1 << lowest_bit)) ? MEM_READ_INTERNAL : MEM_READ_EXTANY;
shflags |= (dev->regs[reg] & (1 << (lowest_bit + 1))) ? MEM_WRITE_INTERNAL : write;
write = (dev->regs[reg] & (1 << lowest_bit)) ? MEM_WRITE_DISABLED : MEM_WRITE_EXTANY;
mem_set_mem_state(base, 0x4000, shflags);
}
shflags = (dev->regs[0x06] & 0x01) ? MEM_READ_INTERNAL : MEM_READ_EXTANY;
shflags |= (dev->regs[0x06] & 0x02) ? MEM_WRITE_INTERNAL : write;
write = (dev->regs[0x06] & 0x01) ? MEM_WRITE_DISABLED : MEM_WRITE_EXTANY;
mem_set_mem_state(0xe0000, 0x10000, shflags);
shflags = (dev->regs[0x06] & 0x04) ? MEM_READ_INTERNAL : MEM_READ_EXTANY;
shflags |= (dev->regs[0x06] & 0x08) ? MEM_WRITE_INTERNAL : write;
write = (dev->regs[0x06] & 0x04) ? MEM_WRITE_DISABLED : MEM_WRITE_EXTANY;
mem_set_mem_state(0xf0000, 0x10000, shflags);
flushmmucache();
}
static void
opti5x7_write(uint16_t addr, uint8_t val, void *priv)
{
opti5x7_t *dev = (opti5x7_t *) priv;
pclog("Write %02x to OPTi 5x7 address %02x\n", val, addr);
switch (addr) {
case 0x22:
dev->idx = val;
break;
case 0x24:
dev->regs[dev->idx] = val;
switch(dev->idx) {
case 0x02:
cpu_cache_ext_enabled = !!(dev->regs[0x02] & 0x04 & 0x08);
break;
case 0x04:
case 0x05:
case 0x06:
opti5x7_recalc(dev);
break;
}
break;
}
}
static uint8_t
opti5x7_read(uint16_t addr, void *priv)
{
uint8_t ret = 0xff;
opti5x7_t *dev = (opti5x7_t *) priv;
switch (addr) {
case 0x24:
pclog("Read from OPTi 5x7 register %02x\n", dev->idx);
ret = dev->regs[dev->idx];
break;
}
return ret;
}
static void
opti5x7_close(void *priv)
{
opti5x7_t *dev = (opti5x7_t *) priv;
free(dev);
}
static void *
opti5x7_init(const device_t *info)
{
opti5x7_t *dev = (opti5x7_t *) malloc(sizeof(opti5x7_t));
memset(dev, 0, sizeof(opti5x7_t));
io_sethandler(0x0022, 0x0001, opti5x7_read, NULL, NULL, opti5x7_write, NULL, NULL, dev);
io_sethandler(0x0024, 0x0001, opti5x7_read, NULL, NULL, opti5x7_write, NULL, NULL, dev);
dev->port_92 = device_add(&port_92_device);
// pclog("OPTi 5x7 init\n");
opti5x7_recalc(dev);
return dev;
}
const device_t opti5x7_device = {
"OPTi 82C5x6/82C5x7",
0,
0,
opti5x7_init, opti5x7_close, NULL,
NULL, NULL, NULL,
NULL
};