blob: 096dd47b5d5d7915671ab17b1844787949208c24 [file] [log] [blame]
/*
* Normal mappings of chips in physical memory for OF devices
*
* Copyright (C) 2006 MontaVista Software Inc.
* Author: Vitaly Wool <vwool@ru.mvista.com>
*
* Revised to handle newer style flash binding by:
* Copyright (C) 2007 David Gibson, IBM Corporation.
*
* 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/slab.h>
#include <linux/device.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/physmap.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/of_device.h>
#include <asm/of_platform.h>
struct physmap_flash_info {
struct mtd_info *mtd;
struct map_info map;
struct resource *res;
#ifdef CONFIG_MTD_PARTITIONS
struct mtd_partition *parts;
#endif
};
#ifdef CONFIG_MTD_PARTITIONS
static int parse_obsolete_partitions(struct of_device *dev,
struct physmap_flash_info *info,
struct device_node *dp)
{
int i, plen, nr_parts;
const struct {
u32 offset, len;
} *part;
const char *names;
part = of_get_property(dp, "partitions", &plen);
if (!part)
return -ENOENT;
dev_warn(&dev->dev, "Device tree uses obsolete partition map binding\n");
nr_parts = plen / sizeof(part[0]);
info->parts = kzalloc(nr_parts * sizeof(struct mtd_partition), GFP_KERNEL);
if (!info->parts) {
printk(KERN_ERR "Can't allocate the flash partition data!\n");
return -ENOMEM;
}
names = of_get_property(dp, "partition-names", &plen);
for (i = 0; i < nr_parts; i++) {
info->parts[i].offset = part->offset;
info->parts[i].size = part->len & ~1;
if (part->len & 1) /* bit 0 set signifies read only partition */
info->parts[i].mask_flags = MTD_WRITEABLE;
if (names && (plen > 0)) {
int len = strlen(names) + 1;
info->parts[i].name = (char *)names;
plen -= len;
names += len;
} else {
info->parts[i].name = "unnamed";
}
part++;
}
return nr_parts;
}
static int __devinit process_partitions(struct physmap_flash_info *info,
struct of_device *dev)
{
const char *partname;
static const char *part_probe_types[]
= { "cmdlinepart", "RedBoot", NULL };
struct device_node *dp = dev->node, *pp;
int nr_parts, i;
/* First look for RedBoot table or partitions on the command
* line, these take precedence over device tree information */
nr_parts = parse_mtd_partitions(info->mtd, part_probe_types,
&info->parts, 0);
if (nr_parts > 0) {
add_mtd_partitions(info->mtd, info->parts, nr_parts);
return 0;
}
/* First count the subnodes */
nr_parts = 0;
for (pp = dp->child; pp; pp = pp->sibling)
nr_parts++;
if (nr_parts) {
info->parts = kzalloc(nr_parts * sizeof(struct mtd_partition),
GFP_KERNEL);
if (!info->parts) {
printk(KERN_ERR "Can't allocate the flash partition data!\n");
return -ENOMEM;
}
for (pp = dp->child, i = 0 ; pp; pp = pp->sibling, i++) {
const u32 *reg;
int len;
reg = of_get_property(pp, "reg", &len);
if (!reg || (len != 2*sizeof(u32))) {
dev_err(&dev->dev, "Invalid 'reg' on %s\n",
dp->full_name);
kfree(info->parts);
info->parts = NULL;
return -EINVAL;
}
info->parts[i].offset = reg[0];
info->parts[i].size = reg[1];
partname = of_get_property(pp, "label", &len);
if (!partname)
partname = of_get_property(pp, "name", &len);
info->parts[i].name = (char *)partname;
if (of_get_property(pp, "read-only", &len))
info->parts[i].mask_flags = MTD_WRITEABLE;
}
} else {
nr_parts = parse_obsolete_partitions(dev, info, dp);
if (nr_parts == -ENOENT)
nr_parts = 0;
}
if (nr_parts < 0)
return nr_parts;
if (nr_parts > 0)
add_mtd_partitions(info->mtd, info->parts, nr_parts);
else
add_mtd_device(info->mtd);
return 0;
}
#else /* MTD_PARTITIONS */
static int __devinit process_partitions(struct physmap_flash_info *info,
struct device_node *dev)
{
add_mtd_device(info->mtd);
return 0;
}
#endif /* MTD_PARTITIONS */
static int of_physmap_remove(struct of_device *dev)
{
struct physmap_flash_info *info;
info = dev_get_drvdata(&dev->dev);
if (info == NULL)
return 0;
dev_set_drvdata(&dev->dev, NULL);
if (info->mtd != NULL) {
#ifdef CONFIG_MTD_PARTITIONS
if (info->parts) {
del_mtd_partitions(info->mtd);
kfree(info->parts);
} else {
del_mtd_device(info->mtd);
}
#else
del_mtd_device(info->mtd);
#endif
map_destroy(info->mtd);
}
if (info->map.virt != NULL)
iounmap(info->map.virt);
if (info->res != NULL) {
release_resource(info->res);
kfree(info->res);
}
return 0;
}
/* Helper function to handle probing of the obsolete "direct-mapped"
* compatible binding, which has an extra "probe-type" property
* describing the type of flash probe necessary. */
static struct mtd_info * __devinit obsolete_probe(struct of_device *dev,
struct map_info *map)
{
struct device_node *dp = dev->node;
const char *of_probe;
struct mtd_info *mtd;
static const char *rom_probe_types[]
= { "cfi_probe", "jedec_probe", "map_rom"};
int i;
dev_warn(&dev->dev, "Device tree uses obsolete \"direct-mapped\" "
"flash binding\n");
of_probe = of_get_property(dp, "probe-type", NULL);
if (!of_probe) {
for (i = 0; i < ARRAY_SIZE(rom_probe_types); i++) {
mtd = do_map_probe(rom_probe_types[i], map);
if (mtd)
return mtd;
}
return NULL;
} else if (strcmp(of_probe, "CFI") == 0) {
return do_map_probe("cfi_probe", map);
} else if (strcmp(of_probe, "JEDEC") == 0) {
return do_map_probe("jedec_probe", map);
} else {
if (strcmp(of_probe, "ROM") != 0)
dev_dbg(&dev->dev, "obsolete_probe: don't know probe type "
"'%s', mapping as rom\n", of_probe);
return do_map_probe("mtd_rom", map);
}
}
static int __devinit of_physmap_probe(struct of_device *dev, const struct of_device_id *match)
{
struct device_node *dp = dev->node;
struct resource res;
struct physmap_flash_info *info;
const char *probe_type = (const char *)match->data;
const u32 *width;
int err;
if (of_address_to_resource(dp, 0, &res)) {
dev_err(&dev->dev, "Can't get the flash mapping!\n");
err = -EINVAL;
goto err_out;
}
dev_dbg(&dev->dev, "physmap flash device: %.8llx at %.8llx\n",
(unsigned long long)res.end - res.start + 1,
(unsigned long long)res.start);
info = kzalloc(sizeof(struct physmap_flash_info), GFP_KERNEL);
if (info == NULL) {
err = -ENOMEM;
goto err_out;
}
memset(info, 0, sizeof(*info));
dev_set_drvdata(&dev->dev, info);
info->res = request_mem_region(res.start, res.end - res.start + 1,
dev->dev.bus_id);
if (info->res == NULL) {
dev_err(&dev->dev, "Could not reserve memory region\n");
err = -ENOMEM;
goto err_out;
}
width = of_get_property(dp, "bank-width", NULL);
if (width == NULL) {
dev_err(&dev->dev, "Can't get the flash bank width!\n");
err = -EINVAL;
goto err_out;
}
info->map.name = dev->dev.bus_id;
info->map.phys = res.start;
info->map.size = res.end - res.start + 1;
info->map.bankwidth = *width;
info->map.virt = ioremap(info->map.phys, info->map.size);
if (info->map.virt == NULL) {
dev_err(&dev->dev, "Failed to ioremap flash region\n");
err = EIO;
goto err_out;
}
simple_map_init(&info->map);
if (probe_type)
info->mtd = do_map_probe(probe_type, &info->map);
else
info->mtd = obsolete_probe(dev, &info->map);
if (info->mtd == NULL) {
dev_err(&dev->dev, "map_probe failed\n");
err = -ENXIO;
goto err_out;
}
info->mtd->owner = THIS_MODULE;
return process_partitions(info, dev);
err_out:
of_physmap_remove(dev);
return err;
return 0;
}
static struct of_device_id of_physmap_match[] = {
{
.compatible = "cfi-flash",
.data = (void *)"cfi_probe",
},
{
/* FIXME: JEDEC chips can't be safely and reliably
* probed, although the mtd code gets it right in
* practice most of the time. We should use the
* vendor and device ids specified by the binding to
* bypass the heuristic probe code, but the mtd layer
* provides, at present, no interface for doing so
* :(. */
.compatible = "jedec-flash",
.data = (void *)"jedec_probe",
},
{
.type = "rom",
.compatible = "direct-mapped"
},
{ },
};
MODULE_DEVICE_TABLE(of, of_physmap_match);
static struct of_platform_driver of_physmap_flash_driver = {
.name = "physmap-flash",
.match_table = of_physmap_match,
.probe = of_physmap_probe,
.remove = of_physmap_remove,
};
static int __init of_physmap_init(void)
{
return of_register_platform_driver(&of_physmap_flash_driver);
}
static void __exit of_physmap_exit(void)
{
of_unregister_platform_driver(&of_physmap_flash_driver);
}
module_init(of_physmap_init);
module_exit(of_physmap_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
MODULE_DESCRIPTION("Configurable MTD map driver for OF");