OpenCloudOS-Kernel/drivers/mtd/maps/walnut.c

121 lines
2.8 KiB
C

/*
* $Id: walnut.c,v 1.3 2005/11/07 11:14:29 gleixner Exp $
*
* Mapping for Walnut flash
* (used ebony.c as a "framework")
*
* Heikki Lindholm <holindho@infradead.org>
*
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <asm/io.h>
#include <asm/ibm4xx.h>
#include <platforms/4xx/walnut.h>
/* these should be in platforms/4xx/walnut.h ? */
#define WALNUT_FLASH_ONBD_N(x) (x & 0x02)
#define WALNUT_FLASH_SRAM_SEL(x) (x & 0x01)
#define WALNUT_FLASH_LOW 0xFFF00000
#define WALNUT_FLASH_HIGH 0xFFF80000
#define WALNUT_FLASH_SIZE 0x80000
static struct mtd_info *flash;
static struct map_info walnut_map = {
.name = "Walnut flash",
.size = WALNUT_FLASH_SIZE,
.bankwidth = 1,
};
/* Actually, OpenBIOS is the last 128 KiB of the flash - better
* partitioning could be made */
static struct mtd_partition walnut_partitions[] = {
{
.name = "OpenBIOS",
.offset = 0x0,
.size = WALNUT_FLASH_SIZE,
/*.mask_flags = MTD_WRITEABLE, */ /* force read-only */
}
};
int __init init_walnut(void)
{
u8 fpga_brds1;
void *fpga_brds1_adr;
void *fpga_status_adr;
unsigned long flash_base;
/* this should already be mapped (platform/4xx/walnut.c) */
fpga_status_adr = ioremap(WALNUT_FPGA_BASE, 8);
if (!fpga_status_adr)
return -ENOMEM;
fpga_brds1_adr = fpga_status_adr+5;
fpga_brds1 = readb(fpga_brds1_adr);
/* iounmap(fpga_status_adr); */
if (WALNUT_FLASH_ONBD_N(fpga_brds1)) {
printk("The on-board flash is disabled (U79 sw 5)!");
return -EIO;
}
if (WALNUT_FLASH_SRAM_SEL(fpga_brds1))
flash_base = WALNUT_FLASH_LOW;
else
flash_base = WALNUT_FLASH_HIGH;
walnut_map.phys = flash_base;
walnut_map.virt =
(void __iomem *)ioremap(flash_base, walnut_map.size);
if (!walnut_map.virt) {
printk("Failed to ioremap flash.\n");
return -EIO;
}
simple_map_init(&walnut_map);
flash = do_map_probe("jedec_probe", &walnut_map);
if (flash) {
flash->owner = THIS_MODULE;
add_mtd_partitions(flash, walnut_partitions,
ARRAY_SIZE(walnut_partitions));
} else {
printk("map probe failed for flash\n");
return -ENXIO;
}
return 0;
}
static void __exit cleanup_walnut(void)
{
if (flash) {
del_mtd_partitions(flash);
map_destroy(flash);
}
if (walnut_map.virt) {
iounmap((void *)walnut_map.virt);
walnut_map.virt = 0;
}
}
module_init(init_walnut);
module_exit(cleanup_walnut);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Heikki Lindholm <holindho@infradead.org>");
MODULE_DESCRIPTION("MTD map and partitions for IBM 405GP Walnut boards");