Commit 3cf7f131 authored by Rafał Miłecki's avatar Rafał Miłecki Committed by David Woodhouse

mtd: bcm47part driver for BCM47XX chipsets

This driver provides parser detecting partitions on BCM47XX flash
memories. It has many differences in comparison to BCM63XX, like:
1) Different CFE with no more trivial MAGICs
2) More partitions types (board_data, ML, POT)
3) Supporting more than 1 flash on a device
which resulted in decision of writing new parser.

It uses generic mtd interface and was successfully tested with Netgear
WNDR4500 router which has 2 flash memories: serial one and NAND one.
Signed-off-by: default avatarRafał Miłecki <zajec5@gmail.com>
Signed-off-by: default avatarArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
parent aa3c5dc5
...@@ -148,6 +148,13 @@ config MTD_BCM63XX_PARTS ...@@ -148,6 +148,13 @@ config MTD_BCM63XX_PARTS
This provides partions parsing for BCM63xx devices with CFE This provides partions parsing for BCM63xx devices with CFE
bootloaders. bootloaders.
config MTD_BCM47XX_PARTS
tristate "BCM47XX partitioning support"
depends on BCM47XX
help
This provides partitions parser for devices based on BCM47xx
boards.
comment "User Modules And Translation Layers" comment "User Modules And Translation Layers"
config MTD_CHAR config MTD_CHAR
......
...@@ -12,6 +12,7 @@ obj-$(CONFIG_MTD_CMDLINE_PARTS) += cmdlinepart.o ...@@ -12,6 +12,7 @@ obj-$(CONFIG_MTD_CMDLINE_PARTS) += cmdlinepart.o
obj-$(CONFIG_MTD_AFS_PARTS) += afs.o obj-$(CONFIG_MTD_AFS_PARTS) += afs.o
obj-$(CONFIG_MTD_AR7_PARTS) += ar7part.o obj-$(CONFIG_MTD_AR7_PARTS) += ar7part.o
obj-$(CONFIG_MTD_BCM63XX_PARTS) += bcm63xxpart.o obj-$(CONFIG_MTD_BCM63XX_PARTS) += bcm63xxpart.o
obj-$(CONFIG_MTD_BCM47XX_PARTS) += bcm47xxpart.o
# 'Users' - code which presents functionality to userspace. # 'Users' - code which presents functionality to userspace.
obj-$(CONFIG_MTD_CHAR) += mtdchar.o obj-$(CONFIG_MTD_CHAR) += mtdchar.o
......
/*
* BCM47XX MTD partitioning
*
* Copyright © 2012 Rafał Miłecki <zajec5@gmail.com>
*
* 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/kernel.h>
#include <linux/slab.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <asm/mach-bcm47xx/nvram.h>
/* 10 parts were found on sflash on Netgear WNDR4500 */
#define BCM47XXPART_MAX_PARTS 12
/*
* Amount of bytes we read when analyzing each block of flash memory.
* Set it big enough to allow detecting partition and reading important data.
*/
#define BCM47XXPART_BYTES_TO_READ 0x404
/* Magics */
#define BOARD_DATA_MAGIC 0x5246504D /* MPFR */
#define POT_MAGIC1 0x54544f50 /* POTT */
#define POT_MAGIC2 0x504f /* OP */
#define ML_MAGIC1 0x39685a42
#define ML_MAGIC2 0x26594131
#define TRX_MAGIC 0x30524448
struct trx_header {
uint32_t magic;
uint32_t length;
uint32_t crc32;
uint16_t flags;
uint16_t version;
uint32_t offset[3];
} __packed;
static void bcm47xxpart_add_part(struct mtd_partition *part, char *name,
u64 offset, uint32_t mask_flags)
{
part->name = name;
part->offset = offset;
part->mask_flags = mask_flags;
}
static int bcm47xxpart_parse(struct mtd_info *master,
struct mtd_partition **pparts,
struct mtd_part_parser_data *data)
{
struct mtd_partition *parts;
uint8_t i, curr_part = 0;
uint32_t *buf;
size_t bytes_read;
uint32_t offset;
uint32_t blocksize = 0x10000;
struct trx_header *trx;
/* Alloc */
parts = kzalloc(sizeof(struct mtd_partition) * BCM47XXPART_MAX_PARTS,
GFP_KERNEL);
buf = kzalloc(BCM47XXPART_BYTES_TO_READ, GFP_KERNEL);
/* Parse block by block looking for magics */
for (offset = 0; offset <= master->size - blocksize;
offset += blocksize) {
/* Nothing more in higher memory */
if (offset >= 0x2000000)
break;
if (curr_part > BCM47XXPART_MAX_PARTS) {
pr_warn("Reached maximum number of partitions, scanning stopped!\n");
break;
}
/* Read beginning of the block */
if (mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ,
&bytes_read, (uint8_t *)buf) < 0) {
pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
offset);
continue;
}
/* CFE has small NVRAM at 0x400 */
if (buf[0x400 / 4] == NVRAM_HEADER) {
bcm47xxpart_add_part(&parts[curr_part++], "boot",
offset, MTD_WRITEABLE);
continue;
}
/* Standard NVRAM */
if (buf[0x000 / 4] == NVRAM_HEADER) {
bcm47xxpart_add_part(&parts[curr_part++], "nvram",
offset, 0);
continue;
}
/*
* board_data starts with board_id which differs across boards,
* but we can use 'MPFR' (hopefully) magic at 0x100
*/
if (buf[0x100 / 4] == BOARD_DATA_MAGIC) {
bcm47xxpart_add_part(&parts[curr_part++], "board_data",
offset, MTD_WRITEABLE);
continue;
}
/* POT(TOP) */
if (buf[0x000 / 4] == POT_MAGIC1 &&
(buf[0x004 / 4] & 0xFFFF) == POT_MAGIC2) {
bcm47xxpart_add_part(&parts[curr_part++], "POT", offset,
MTD_WRITEABLE);
continue;
}
/* ML */
if (buf[0x010 / 4] == ML_MAGIC1 &&
buf[0x014 / 4] == ML_MAGIC2) {
bcm47xxpart_add_part(&parts[curr_part++], "ML", offset,
MTD_WRITEABLE);
continue;
}
/* TRX */
if (buf[0x000 / 4] == TRX_MAGIC) {
trx = (struct trx_header *)buf;
i = 0;
/* We have LZMA loader if offset[2] points to sth */
if (trx->offset[2]) {
bcm47xxpart_add_part(&parts[curr_part++],
"loader",
offset + trx->offset[i],
0);
i++;
}
bcm47xxpart_add_part(&parts[curr_part++], "linux",
offset + trx->offset[i], 0);
i++;
/*
* Pure rootfs size is known and can be calculated as:
* trx->length - trx->offset[i]. We don't fill it as
* we want to have jffs2 (overlay) in the same mtd.
*/
bcm47xxpart_add_part(&parts[curr_part++], "rootfs",
offset + trx->offset[i], 0);
i++;
/*
* We have whole TRX scanned, skip to the next part. Use
* roundown (not roundup), as the loop will increase
* offset in next step.
*/
offset = rounddown(offset + trx->length, blocksize);
continue;
}
}
kfree(buf);
/*
* Assume that partitions end at the beginning of the one they are
* followed by.
*/
for (i = 0; i < curr_part - 1; i++)
parts[i].size = parts[i + 1].offset - parts[i].offset;
if (curr_part > 0)
parts[curr_part - 1].size =
master->size - parts[curr_part - 1].offset;
*pparts = parts;
return curr_part;
};
static struct mtd_part_parser bcm47xxpart_mtd_parser = {
.owner = THIS_MODULE,
.parse_fn = bcm47xxpart_parse,
.name = "bcm47xxpart",
};
static int __init bcm47xxpart_init(void)
{
return register_mtd_parser(&bcm47xxpart_mtd_parser);
}
static void __exit bcm47xxpart_exit(void)
{
deregister_mtd_parser(&bcm47xxpart_mtd_parser);
}
module_init(bcm47xxpart_init);
module_exit(bcm47xxpart_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MTD partitioning for BCM47XX flash memories");
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