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author | Michael Schwingen <michael@schwingen.org> | 2008-02-18 22:16:35 (GMT) |
---|---|---|
committer | Stefan Roese <sr@denx.de> | 2008-02-21 16:12:19 (GMT) |
commit | 1ba639da5604a64b3ed884a2cbb1c5414a9fa728 (patch) | |
tree | 67fc8f460e38a920281717647949a69fdd9956c2 | |
parent | 928d1d77f8623c120d8763e20e1ca58df9c5c4c6 (diff) | |
download | u-boot-1ba639da5604a64b3ed884a2cbb1c5414a9fa728.tar.xz |
CFI: Do not use uninitialized cmd_reset
Do not use uninitialized cmd_reset; issue both AMD and Intel reset
commands instead
From a short test, it looks like AMD-style flash roms treat *any* unknown
command write as a reset, at least when in CFI Query mode, so issuing the
Intel reset command to AMD-style flashs seems safe (from the small sample I
have), plus the 3-cycle magic sequence should kick the state machine into
the right state even without a reset command. Since the AMD-style flashs
require the unlock sequence for real operation, I chose to try the AMD reset
command first, so that Intel flashs do no see an invalid command prior to
the CFI query.
I have tested the patch on AM29LV320-style flashs from Fujitsu and Macronix,
plus Intel StrataFlash.
Signed-off-by: Michael Schwingen <michael@schwingen.org>
Signed-off-by: Stefan Roese <sr@denx.de>
-rw-r--r-- | drivers/mtd/cfi_flash.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c index eb509f5..439c950 100644 --- a/drivers/mtd/cfi_flash.c +++ b/drivers/mtd/cfi_flash.c @@ -1538,7 +1538,12 @@ static int __flash_detect_cfi (flash_info_t * info, struct cfi_qry *qry) { int cfi_offset; - flash_write_cmd (info, 0, 0, info->cmd_reset); + /* We do not yet know what kind of commandset to use, so we issue + the reset command in both Intel and AMD variants, in the hope + that AMD flash roms ignore the Intel command. */ + flash_write_cmd (info, 0, 0, AMD_CMD_RESET); + flash_write_cmd (info, 0, 0, FLASH_CMD_RESET); + for (cfi_offset=0; cfi_offset < sizeof(flash_offset_cfi) / sizeof(uint); cfi_offset++) { |