OpenCloudOS-Kernel/drivers/mtd/maps/ixp2000.c

254 lines
6.0 KiB
C

/*
* drivers/mtd/maps/ixp2000.c
*
* Mapping for the Intel XScale IXP2000 based systems
*
* Copyright (C) 2002 Intel Corp.
* Copyright (C) 2003-2004 MontaVista Software, Inc.
*
* Original Author: Naeem M Afzal <naeem.m.afzal@intel.com>
* Maintainer: Deepak Saxena <dsaxena@plexity.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <asm/io.h>
#include <mach/hardware.h>
#include <asm/mach/flash.h>
#include <linux/reboot.h>
struct ixp2000_flash_info {
struct mtd_info *mtd;
struct map_info map;
struct resource *res;
};
static inline unsigned long flash_bank_setup(struct map_info *map, unsigned long ofs)
{
unsigned long (*set_bank)(unsigned long) =
(unsigned long(*)(unsigned long))map->map_priv_2;
return (set_bank ? set_bank(ofs) : ofs);
}
#ifdef __ARMEB__
/*
* Rev A0 and A1 of IXP2400 silicon have a broken addressing unit which
* causes the lower address bits to be XORed with 0x11 on 8 bit accesses
* and XORed with 0x10 on 16 bit accesses. See the spec update, erratum 44.
*/
static int erratum44_workaround = 0;
static inline unsigned long address_fix8_write(unsigned long addr)
{
if (erratum44_workaround) {
return (addr ^ 3);
}
return addr;
}
#else
#define address_fix8_write(x) (x)
#endif
static map_word ixp2000_flash_read8(struct map_info *map, unsigned long ofs)
{
map_word val;
val.x[0] = *((u8 *)(map->map_priv_1 + flash_bank_setup(map, ofs)));
return val;
}
/*
* We can't use the standard memcpy due to the broken SlowPort
* address translation on rev A0 and A1 silicon and the fact that
* we have banked flash.
*/
static void ixp2000_flash_copy_from(struct map_info *map, void *to,
unsigned long from, ssize_t len)
{
from = flash_bank_setup(map, from);
while(len--)
*(__u8 *) to++ = *(__u8 *)(map->map_priv_1 + from++);
}
static void ixp2000_flash_write8(struct map_info *map, map_word d, unsigned long ofs)
{
*(__u8 *) (address_fix8_write(map->map_priv_1 +
flash_bank_setup(map, ofs))) = d.x[0];
}
static void ixp2000_flash_copy_to(struct map_info *map, unsigned long to,
const void *from, ssize_t len)
{
to = flash_bank_setup(map, to);
while(len--) {
unsigned long tmp = address_fix8_write(map->map_priv_1 + to++);
*(__u8 *)(tmp) = *(__u8 *)(from++);
}
}
static int ixp2000_flash_remove(struct platform_device *dev)
{
struct flash_platform_data *plat = dev->dev.platform_data;
struct ixp2000_flash_info *info = platform_get_drvdata(dev);
platform_set_drvdata(dev, NULL);
if(!info)
return 0;
if (info->mtd) {
mtd_device_unregister(info->mtd);
map_destroy(info->mtd);
}
if (info->map.map_priv_1)
iounmap((void *) info->map.map_priv_1);
if (info->res) {
release_resource(info->res);
kfree(info->res);
}
if (plat->exit)
plat->exit();
return 0;
}
static int ixp2000_flash_probe(struct platform_device *dev)
{
static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };
struct ixp2000_flash_data *ixp_data = dev->dev.platform_data;
struct flash_platform_data *plat;
struct ixp2000_flash_info *info;
unsigned long window_size;
int err = -1;
if (!ixp_data)
return -ENODEV;
plat = ixp_data->platform_data;
if (!plat)
return -ENODEV;
window_size = resource_size(dev->resource);
dev_info(&dev->dev, "Probe of IXP2000 flash(%d banks x %dMiB)\n",
ixp_data->nr_banks, ((u32)window_size >> 20));
if (plat->width != 1) {
dev_err(&dev->dev, "IXP2000 MTD map only supports 8-bit mode, asking for %d\n",
plat->width * 8);
return -EIO;
}
info = kzalloc(sizeof(struct ixp2000_flash_info), GFP_KERNEL);
if(!info) {
err = -ENOMEM;
goto Error;
}
platform_set_drvdata(dev, info);
/*
* Tell the MTD layer we're not 1:1 mapped so that it does
* not attempt to do a direct access on us.
*/
info->map.phys = NO_XIP;
info->map.size = ixp_data->nr_banks * window_size;
info->map.bankwidth = 1;
/*
* map_priv_2 is used to store a ptr to the bank_setup routine
*/
info->map.map_priv_2 = (unsigned long) ixp_data->bank_setup;
info->map.name = dev_name(&dev->dev);
info->map.read = ixp2000_flash_read8;
info->map.write = ixp2000_flash_write8;
info->map.copy_from = ixp2000_flash_copy_from;
info->map.copy_to = ixp2000_flash_copy_to;
info->res = request_mem_region(dev->resource->start,
resource_size(dev->resource),
dev_name(&dev->dev));
if (!info->res) {
dev_err(&dev->dev, "Could not reserve memory region\n");
err = -ENOMEM;
goto Error;
}
info->map.map_priv_1 =
(unsigned long)ioremap(dev->resource->start,
resource_size(dev->resource));
if (!info->map.map_priv_1) {
dev_err(&dev->dev, "Failed to ioremap flash region\n");
err = -EIO;
goto Error;
}
#if defined(__ARMEB__)
/*
* Enable erratum 44 workaround for NPUs with broken slowport
*/
erratum44_workaround = ixp2000_has_broken_slowport();
dev_info(&dev->dev, "Erratum 44 workaround %s\n",
erratum44_workaround ? "enabled" : "disabled");
#endif
info->mtd = do_map_probe(plat->map_name, &info->map);
if (!info->mtd) {
dev_err(&dev->dev, "map_probe failed\n");
err = -ENXIO;
goto Error;
}
info->mtd->owner = THIS_MODULE;
err = mtd_device_parse_register(info->mtd, probes, NULL, NULL, 0);
if (err)
goto Error;
return 0;
Error:
ixp2000_flash_remove(dev);
return err;
}
static struct platform_driver ixp2000_flash_driver = {
.probe = ixp2000_flash_probe,
.remove = ixp2000_flash_remove,
.driver = {
.name = "IXP2000-Flash",
.owner = THIS_MODULE,
},
};
module_platform_driver(ixp2000_flash_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
MODULE_ALIAS("platform:IXP2000-Flash");