pcem/src/i440fx.c
2020-11-14 19:33:57 +00:00

183 lines
6.4 KiB
C

#include <string.h>
#include "ibm.h"
#include "io.h"
#include "keyboard_at.h"
#include "mem.h"
#include "pci.h"
#include "x86.h"
#include "i440fx.h"
static uint8_t card_i440fx[256];
static void i440fx_map(uint32_t addr, uint32_t size, int state)
{
switch (state & 3)
{
case 0:
mem_set_mem_state(addr, size, MEM_READ_EXTERNAL | MEM_WRITE_EXTERNAL);
break;
case 1:
mem_set_mem_state(addr, size, MEM_READ_INTERNAL | MEM_WRITE_EXTERNAL);
break;
case 2:
mem_set_mem_state(addr, size, MEM_READ_EXTERNAL | MEM_WRITE_INTERNAL);
break;
case 3:
mem_set_mem_state(addr, size, MEM_READ_INTERNAL | MEM_WRITE_INTERNAL);
break;
}
flushmmucache_nopc();
}
void i440fx_write(int func, int addr, uint8_t val, void *priv)
{
if (func)
return;
if (addr >= 0x10 && addr < 0x4f)
return;
switch (addr)
{
case 0x00: case 0x01: case 0x02: case 0x03:
case 0x08: case 0x09: case 0x0a: case 0x0b:
case 0x0c: case 0x0e:
return;
case 0x04: /*Command register*/
val &= 0x02;
val |= 0x04;
break;
case 0x05:
val = 0;
break;
case 0x06: /*Status*/
val = 0;
break;
case 0x07:
val = 0x02;
break;
case 0x59: /*PAM0*/
if ((card_i440fx[0x59] ^ val) & 0xf0)
{
i440fx_map(0xf0000, 0x10000, val >> 4);
}
pclog("i440fx_write : PAM0 write %02X\n", val);
break;
case 0x5a: /*PAM1*/
if ((card_i440fx[0x5a] ^ val) & 0x0f)
i440fx_map(0xc0000, 0x04000, val & 0xf);
if ((card_i440fx[0x5a] ^ val) & 0xf0)
i440fx_map(0xc4000, 0x04000, val >> 4);
break;
case 0x5b: /*PAM2*/
if ((card_i440fx[0x5b] ^ val) & 0x0f)
i440fx_map(0xc8000, 0x04000, val & 0xf);
if ((card_i440fx[0x5b] ^ val) & 0xf0)
i440fx_map(0xcc000, 0x04000, val >> 4);
break;
case 0x5c: /*PAM3*/
if ((card_i440fx[0x5c] ^ val) & 0x0f)
i440fx_map(0xd0000, 0x04000, val & 0xf);
if ((card_i440fx[0x5c] ^ val) & 0xf0)
i440fx_map(0xd4000, 0x04000, val >> 4);
break;
case 0x5d: /*PAM4*/
if ((card_i440fx[0x5d] ^ val) & 0x0f)
i440fx_map(0xd8000, 0x04000, val & 0xf);
if ((card_i440fx[0x5d] ^ val) & 0xf0)
i440fx_map(0xdc000, 0x04000, val >> 4);
break;
case 0x5e: /*PAM5*/
if ((card_i440fx[0x5e] ^ val) & 0x0f)
i440fx_map(0xe0000, 0x04000, val & 0xf);
if ((card_i440fx[0x5e] ^ val) & 0xf0)
i440fx_map(0xe4000, 0x04000, val >> 4);
pclog("i440fx_write : PAM5 write %02X\n", val);
break;
case 0x5f: /*PAM6*/
if ((card_i440fx[0x5f] ^ val) & 0x0f)
i440fx_map(0xe8000, 0x04000, val & 0xf);
if ((card_i440fx[0x5f] ^ val) & 0xf0)
i440fx_map(0xec000, 0x04000, val >> 4);
pclog("i440fx_write : PAM6 write %02X\n", val);
break;
case 0x72: /*SMRAM*/
pclog("Write SMRAM %02x\n", val);
val = (val & 0x78) | 2; /*SMRAM always at A0000-BFFFF*/
val |= (card_i440fx[0x72] & 0x10); /*D_LCK can not be cleared by software*/
if (val & 0x10) /*D_LCK locks D_OPEN and G_SMRAME*/
{
val &= ~0x48; /*D_OPEN is forced to 0, G_SMRAME is read only*/
val |= (card_i440fx[0x72] & 0x08);
}
if ((card_i440fx[0x72] ^ val) & 0x40)
{
if (val & 0x40) /*SMRAM enabled*/
{
pclog("Enable SMRAM\n");
mem_set_mem_state(0xa0000, 0x20000, MEM_READ_INTERNAL | MEM_WRITE_INTERNAL);
}
else
{
pclog("Disable SMRAM\n");
mem_set_mem_state(0xa0000, 0x20000, MEM_READ_EXTERNAL | MEM_WRITE_EXTERNAL);
}
}
break;
}
card_i440fx[addr] = val;
}
uint8_t i440fx_read(int func, int addr, void *priv)
{
if (func)
return 0xff;
return card_i440fx[addr];
}
static void i440fx_smram_enable(void)
{
if (card_i440fx[0x72] & 8)
mem_set_mem_state(0xa0000, 0x20000, MEM_READ_INTERNAL | MEM_WRITE_INTERNAL);
}
static void i440fx_smram_disable(void)
{
if (card_i440fx[0x72] & 8)
mem_set_mem_state(0xa0000, 0x20000, MEM_READ_EXTERNAL | MEM_WRITE_EXTERNAL);
}
void i440fx_init()
{
pci_add_specific(0, i440fx_read, i440fx_write, NULL);
memset(card_i440fx, 0, 256);
card_i440fx[0x00] = 0x86; card_i440fx[0x01] = 0x80; /*Intel*/
card_i440fx[0x02] = 0x37; card_i440fx[0x03] = 0x12; /*82441FX*/
card_i440fx[0x04] = 0x06; card_i440fx[0x05] = 0x00;
card_i440fx[0x06] = 0x80; card_i440fx[0x07] = 0x02;
card_i440fx[0x08] = 0x00; /*A0 stepping*/
card_i440fx[0x09] = 0x00; card_i440fx[0x0a] = 0x00; card_i440fx[0x0b] = 0x06;
card_i440fx[0x51] = 0x84; /*Uniprocessor, 66 MHz bus*/
card_i440fx[0x53] = 0x80;
card_i440fx[0x57] = 0x01;
card_i440fx[0x58] = 0x10;
card_i440fx[0x60] = card_i440fx[0x61] = card_i440fx[0x62] = card_i440fx[0x63] = card_i440fx[0x64] = 0x01;
card_i440fx[0x71] = 0x10;
card_i440fx[0x72] = 0x02;
smram_enable = i440fx_smram_enable;
smram_disable = i440fx_smram_disable;
}
void i440fx_reset()
{
i440fx_write(0, 0x59, 0xf, NULL); /*Should reset all PCI devices, but just set PAM0 to point to ROM for now*/
}