linux/drivers/media/pci/cobalt/cobalt-flash.c

117 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Cobalt NOR flash functions
*
* Copyright 2012-2015 Cisco Systems, Inc. and/or its affiliates.
* All rights reserved.
*/
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/cfi.h>
#include <linux/time.h>
#include "cobalt-flash.h"
#define ADRS(offset) (COBALT_BUS_FLASH_BASE + offset)
static struct map_info cobalt_flash_map = {
.name = "cobalt-flash",
.bankwidth = 2, /* 16 bits */
.size = 0x4000000, /* 64MB */
.phys = 0, /* offset */
};
static map_word flash_read16(struct map_info *map, unsigned long offset)
{
map_word r;
r.x[0] = cobalt_bus_read32(map->virt, ADRS(offset));
if (offset & 0x2)
r.x[0] >>= 16;
else
r.x[0] &= 0x0000ffff;
return r;
}
static void flash_write16(struct map_info *map, const map_word datum,
unsigned long offset)
{
u16 data = (u16)datum.x[0];
cobalt_bus_write16(map->virt, ADRS(offset), data);
}
static void flash_copy_from(struct map_info *map, void *to,
unsigned long from, ssize_t len)
{
u32 src = from;
u8 *dest = to;
u32 data;
while (len) {
data = cobalt_bus_read32(map->virt, ADRS(src));
do {
*dest = data >> (8 * (src & 3));
src++;
dest++;
len--;
} while (len && (src % 4));
}
}
static void flash_copy_to(struct map_info *map, unsigned long to,
const void *from, ssize_t len)
{
const u8 *src = from;
u32 dest = to;
pr_info("%s: offset 0x%x: length %zu\n", __func__, dest, len);
while (len) {
u16 data = 0xffff;
do {
data = *src << (8 * (dest & 1));
src++;
dest++;
len--;
} while (len && (dest % 2));
cobalt_bus_write16(map->virt, ADRS(dest - 2), data);
}
}
int cobalt_flash_probe(struct cobalt *cobalt)
{
struct map_info *map = &cobalt_flash_map;
struct mtd_info *mtd;
BUG_ON(!map_bankwidth_supported(map->bankwidth));
map->virt = cobalt->bar1;
map->read = flash_read16;
map->write = flash_write16;
map->copy_from = flash_copy_from;
map->copy_to = flash_copy_to;
mtd = do_map_probe("cfi_probe", map);
cobalt->mtd = mtd;
if (!mtd) {
cobalt_err("Probe CFI flash failed!\n");
return -1;
}
mtd->owner = THIS_MODULE;
mtd->dev.parent = &cobalt->pci_dev->dev;
mtd_device_register(mtd, NULL, 0);
return 0;
}
void cobalt_flash_remove(struct cobalt *cobalt)
{
if (cobalt->mtd) {
mtd_device_unregister(cobalt->mtd);
map_destroy(cobalt->mtd);
}
}