Revert "mtd: bcm47xxpart: improve probing of nvram partition"

This reverts commit be3781b71a.

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>
This commit is contained in:
Rafał Miłecki 2013-03-07 09:02:38 +01:00 committed by David Woodhouse
parent 48476df998
commit 5ca1088f10

View File

@ -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;
}