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authorRafał Miłecki <zajec5@gmail.com>2013-03-07 09:02:38 +0100
committerDavid Woodhouse <David.Woodhouse@intel.com>2013-03-08 11:35:10 +0000
commit5ca1088f10d6179a610067ebedc56edc7d98b986 (patch)
tree185216e0e0994451aa99e235d6524ac65d634f7a /drivers/mtd/bcm47xxpart.c
parent48476df99894492a0f7239f2f3c9a2dde4ff38e2 (diff)
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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>
Diffstat (limited to 'drivers/mtd/bcm47xxpart.c')
-rw-r--r--drivers/mtd/bcm47xxpart.c22
1 files changed, 9 insertions, 13 deletions
diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c
index 63feb75cc8e0..4552afbad4d0 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;
}