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Added SST 39SF010 flash for VA-503+.

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This commit is contained in:
SarahW 2019-03-31 11:29:07 +01:00
commit e3d5309e23
5 changed files with 223 additions and 2 deletions
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218
src/sst39sf010.c Normal file
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#include <stdlib.h>
#include "ibm.h"
#include "device.h"
#include "mem.h"
#include "sst39sf010.h"
typedef struct sst_t
{
int command_state;
int id_mode;
int erase;
int dirty;
char flash_path[1024];
} sst_t;
#define SST_CHIP_ERASE 0x10
#define SST_SECTOR_ERASE 0x30
#define SST_ERASE 0x80
#define SST_SET_ID_MODE 0x90
#define SST_BYTE_PROGRAM 0xa0
#define SST_CLEAR_ID_MODE 0xf0
static void set_id_mode(sst_t *sst);
static void clear_id_mode(sst_t *sst);
static void sst_new_command(sst_t *sst, uint8_t val)
{
switch (val)
{
case SST_CHIP_ERASE:
if (sst->erase)
memset(rom, 0xff, 0x20000);
sst->command_state = 0;
sst->erase = 0;
break;
case SST_ERASE:
sst->command_state = 0;
sst->erase = 1;
break;
case SST_SET_ID_MODE:
if (!sst->id_mode)
set_id_mode(sst);
sst->command_state = 0;
sst->erase = 0;
break;
case SST_BYTE_PROGRAM:
sst->command_state = 3;
sst->erase = 0;
break;
case SST_CLEAR_ID_MODE:
if (sst->id_mode)
clear_id_mode(sst);
sst->command_state = 0;
sst->erase = 0;
break;
default:
sst->command_state = 0;
sst->erase = 0;
}
}
static void sst_sector_erase(sst_t *sst, uint32_t addr)
{
// pclog("SST sector erase %08x\n", addr);
memset(&rom[addr & 0x1f000], 0xff, 4096);
sst->dirty = 1;
}
static uint8_t sst_read_id(uint32_t addr, void *p)
{
if ((addr & 0xffff) == 0)
return 0xbf; /*SST*/
else if ((addr & 0xffff) == 1)
return 0xb5; /*39SF010*/
else
return 0xff;
// fatal("sst_read_id: addr=%08x\n", addr);
}
static void sst_write(uint32_t addr, uint8_t val, void *p)
{
sst_t *sst = (sst_t *)p;
// pclog("sst_write: addr=%08x val=%02x state=%i\n", addr, val, sst->command_state);
switch (sst->command_state)
{
case 0:
if (val == 0xf0)
{
if (sst->id_mode)
clear_id_mode(sst);
}
else if ((addr & 0xffff) == 0x5555 && val == 0xaa)
sst->command_state = 1;
else
sst->command_state = 0;
break;
case 1:
if ((addr & 0xffff) == 0x2aaa && val == 0x55)
sst->command_state = 2;
else
sst->command_state = 0;
break;
case 2:
if ((addr & 0xffff) == 0x5555)
sst_new_command(sst, val);
else if (val == SST_SECTOR_ERASE && sst->erase)
{
sst_sector_erase(sst, addr);
sst->command_state = 0;
}
else
sst->command_state = 0;
break;
case 3:
// pclog("Byte program %08x %02x\n", addr, val);
rom[addr & 0x1ffff] = val;
sst->command_state = 0;
sst->dirty = 1;
break;
}
}
static void set_id_mode(sst_t *sst)
{
int c;
for (c = 0; c < 8; c++)
{
mem_mapping_set_handler(&bios_mapping[c],
sst_read_id, NULL, NULL,
sst_write, NULL, NULL);
mem_mapping_set_p(&bios_mapping[c], sst);
mem_mapping_set_handler(&bios_high_mapping[c],
sst_read_id, NULL, NULL,
sst_write, NULL, NULL);
mem_mapping_set_p(&bios_high_mapping[c], sst);
}
sst->id_mode = 1;
}
static void clear_id_mode(sst_t *sst)
{
int c;
for (c = 0; c < 8; c++)
{
mem_mapping_set_handler(&bios_mapping[c],
mem_read_bios, mem_read_biosw, mem_read_biosl,
sst_write, NULL, NULL);
mem_mapping_set_p(&bios_mapping[c], sst);
mem_mapping_set_handler(&bios_high_mapping[c],
mem_read_bios, mem_read_biosw, mem_read_biosl,
sst_write, NULL, NULL);
mem_mapping_set_p(&bios_high_mapping[c], sst);
}
sst->id_mode = 0;
}
static void *sst_39sf010_init()
{
FILE *f;
sst_t *sst = malloc(sizeof(sst_t));
memset(sst, 0, sizeof(sst_t));
switch(romset)
{
case ROM_FIC_VA503P:
strcpy(sst->flash_path, "fic_va503p/");
break;
default:
fatal("sst_39sf010_init on unsupported ROM set %i\n", romset);
}
strcat(sst->flash_path, "flash.bin");
f = romfopen(sst->flash_path, "rb");
if (f)
{
fread(rom, 0x20000, 1, f);
fclose(f);
}
clear_id_mode(sst);
return sst;
}
static void sst_39sf010_close(void *p)
{
sst_t *sst = (sst_t *)p;
if (sst->dirty)
{
FILE *f = romfopen(sst->flash_path, "wb");
fwrite(rom, 0x20000, 1, f);
fclose(f);
}
free(sst);
}
device_t sst_39sf010_device =
{
"SST 39SF010 Flash BIOS",
0,
sst_39sf010_init,
sst_39sf010_close,
NULL,
NULL,
NULL,
NULL,
NULL
};