blob: 9fc1f727aa766aed96cf74020fff3beef50e0b19 [file] [log] [blame] [edit]
// SPDX-License-Identifier: GPL-2.0
/*
* tsunami_flash.c
*
* flash chip on alpha ds10...
*/
#include <asm/io.h>
#include <asm/core_tsunami.h>
#include <linux/init.h>
#include <linux/mtd/map.h>
#include <linux/mtd/mtd.h>
#define FLASH_ENABLE_PORT 0x00C00001
#define FLASH_ENABLE_BYTE 0x01
#define FLASH_DISABLE_BYTE 0x00
#define MAX_TIG_FLASH_SIZE (12*1024*1024)
static inline map_word tsunami_flash_read8(struct map_info *map, unsigned long offset)
{
map_word val;
val.x[0] = tsunami_tig_readb(offset);
return val;
}
static void tsunami_flash_write8(struct map_info *map, map_word value, unsigned long offset)
{
tsunami_tig_writeb(value.x[0], offset);
}
static void tsunami_flash_copy_from(
struct map_info *map, void *addr, unsigned long offset, ssize_t len)
{
unsigned char *dest;
dest = addr;
while(len && (offset < MAX_TIG_FLASH_SIZE)) {
*dest = tsunami_tig_readb(offset);
offset++;
dest++;
len--;
}
}
static void tsunami_flash_copy_to(
struct map_info *map, unsigned long offset,
const void *addr, ssize_t len)
{
const unsigned char *src;
src = addr;
while(len && (offset < MAX_TIG_FLASH_SIZE)) {
tsunami_tig_writeb(*src, offset);
offset++;
src++;
len--;
}
}
/*
* Deliberately don't provide operations wider than 8 bits. I don't
* have then and it scares me to think how you could mess up if
* you tried to use them. Buswidth is correctly so I'm safe.
*/
static struct map_info tsunami_flash_map = {
.name = "flash chip on the Tsunami TIG bus",
.size = MAX_TIG_FLASH_SIZE,
.phys = NO_XIP,
.bankwidth = 1,
.read = tsunami_flash_read8,
.copy_from = tsunami_flash_copy_from,
.write = tsunami_flash_write8,
.copy_to = tsunami_flash_copy_to,
};
static struct mtd_info *tsunami_flash_mtd;
static void __exit cleanup_tsunami_flash(void)
{
struct mtd_info *mtd;
mtd = tsunami_flash_mtd;
if (mtd) {
mtd_device_unregister(mtd);
map_destroy(mtd);
}
tsunami_flash_mtd = 0;
}
static const char * const rom_probe_types[] = {
"cfi_probe", "jedec_probe", "map_rom", NULL };
static int __init init_tsunami_flash(void)
{
const char * const *type;
tsunami_tig_writeb(FLASH_ENABLE_BYTE, FLASH_ENABLE_PORT);
tsunami_flash_mtd = 0;
type = rom_probe_types;
for(; !tsunami_flash_mtd && *type; type++) {
tsunami_flash_mtd = do_map_probe(*type, &tsunami_flash_map);
}
if (tsunami_flash_mtd) {
tsunami_flash_mtd->owner = THIS_MODULE;
mtd_device_register(tsunami_flash_mtd, NULL, 0);
return 0;
}
return -ENXIO;
}
module_init(init_tsunami_flash);
module_exit(cleanup_tsunami_flash);