From 5c9c11e1c47c2101253a95c54ef72e13edcc728a Mon Sep 17 00:00:00 2001 From: Mike Rapoport Date: Tue, 27 May 2008 11:20:03 +0300 Subject: [MTD] [NOR] Add support for flash chips with ID in bank other than 0 According to JEDEC "Standard Manufacturer's Identification Code" (http://www.jedec.org/download/search/jep106W.pdf) several first banks of NOR flash can contain 0x7f instead of actual ID. This patch adds support for reading manufacturer ID from banks other than 0. Signed-off-by: Mike Rapoport Signed-off-by: David Woodhouse --- drivers/mtd/chips/jedec_probe.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/mtd/chips/jedec_probe.c b/drivers/mtd/chips/jedec_probe.c index b717f1a5d6b2..279fe60b7855 100644 --- a/drivers/mtd/chips/jedec_probe.c +++ b/drivers/mtd/chips/jedec_probe.c @@ -37,6 +37,7 @@ #define MANUFACTURER_ST 0x0020 #define MANUFACTURER_TOSHIBA 0x0098 #define MANUFACTURER_WINBOND 0x00da +#define CONTINUATION_CODE 0x007f /* AMD */ @@ -1760,9 +1761,21 @@ static inline u32 jedec_read_mfr(struct map_info *map, uint32_t base, { map_word result; unsigned long mask; - u32 ofs = cfi_build_cmd_addr(0, cfi_interleave(cfi), cfi->device_type); - mask = (1 << (cfi->device_type * 8)) -1; - result = map_read(map, base + ofs); + int bank = 0; + + /* According to JEDEC "Standard Manufacturer's Identification Code" + * (http://www.jedec.org/download/search/jep106W.pdf) + * several first banks can contain 0x7f instead of actual ID + */ + do { + uint32_t ofs = cfi_build_cmd_addr(0 + (bank << 8), + cfi_interleave(cfi), + cfi->device_type); + mask = (1 << (cfi->device_type * 8)) - 1; + result = map_read(map, base + ofs); + bank++; + } while ((result.x[0] & mask) == CONTINUATION_CODE); + return result.x[0] & mask; } -- cgit v1.2.2