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author | Rafał Miłecki <zajec5@gmail.com> | 2013-03-07 08:02:38 (GMT) |
---|---|---|
committer | David Woodhouse <David.Woodhouse@intel.com> | 2013-03-08 11:35:10 (GMT) |
commit | 5ca1088f10d6179a610067ebedc56edc7d98b986 (patch) | |
tree | 185216e0e0994451aa99e235d6524ac65d634f7a | |
parent | 48476df99894492a0f7239f2f3c9a2dde4ff38e2 (diff) | |
download | linux-5ca1088f10d6179a610067ebedc56edc7d98b986.tar.xz |
Revert "mtd: bcm47xxpart: improve probing of nvram partition"
This reverts commit be3781b71ac03723b552dc156931620634ef1b22.
Some CFE bootloaders have NVRAM at offset 0x1000. With that patch we
were detecting such a bootloaders as a standard NVRAM partition.
Changing anything in this pseudo-NVRAM resulted in corrupted bootloader
and bricked device!
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
-rw-r--r-- | drivers/mtd/bcm47xxpart.c | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c index 63feb75..4552afb 100644 --- a/drivers/mtd/bcm47xxpart.c +++ b/drivers/mtd/bcm47xxpart.c @@ -19,6 +19,12 @@ /* 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 */ @@ -57,17 +63,14 @@ static int bcm47xxpart_parse(struct mtd_info *master, struct trx_header *trx; int trx_part = -1; int last_trx_part = -1; - int max_bytes_to_read = 0x8004; if (blocksize <= 0x10000) blocksize = 0x10000; - if (blocksize == 0x20000) - max_bytes_to_read = 0x18004; /* Alloc */ parts = kzalloc(sizeof(struct mtd_partition) * BCM47XXPART_MAX_PARTS, GFP_KERNEL); - buf = kzalloc(max_bytes_to_read, GFP_KERNEL); + buf = kzalloc(BCM47XXPART_BYTES_TO_READ, GFP_KERNEL); /* Parse block by block looking for magics */ for (offset = 0; offset <= master->size - blocksize; @@ -82,7 +85,7 @@ static int bcm47xxpart_parse(struct mtd_info *master, } /* Read beginning of the block */ - if (mtd_read(master, offset, max_bytes_to_read, + 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); @@ -97,16 +100,9 @@ static int bcm47xxpart_parse(struct mtd_info *master, } /* Standard NVRAM */ - if (buf[0x000 / 4] == NVRAM_HEADER || - buf[0x1000 / 4] == NVRAM_HEADER || - buf[0x8000 / 4] == NVRAM_HEADER || - (blocksize == 0x20000 && ( - buf[0x10000 / 4] == NVRAM_HEADER || - buf[0x11000 / 4] == NVRAM_HEADER || - buf[0x18000 / 4] == NVRAM_HEADER))) { + if (buf[0x000 / 4] == NVRAM_HEADER) { bcm47xxpart_add_part(&parts[curr_part++], "nvram", offset, 0); - offset = rounddown(offset, blocksize); continue; } |