[U-Boot] [PATCH] for JEDEC flash, command of word programing should be issued relatvie to base

Po-Yu Chuang ratbert.chuang at gmail.com
Tue Jul 7 07:27:35 CEST 2009


For JEDEC flash, we should issue word programming command relative to
base address rather than sector base address. Original source makes
SST Flash fails to program sectors which are not on the 0x10000 boundaries.

e.g.
SST39LF040 uses addr1=0x5555 and addr2=0x2AAA, however, each sector
is 0x1000 bytes.

Thus, if we issue command to "sector base (0x41000) + offset(0x5555)",
it sends to 0x46555 and the chip fails to recognize that address.

This patch is tested with SST39LF040.

Signed-off-by: Po-Yu Chuang <ratbert at faraday-tech.com>
---
 drivers/mtd/cfi_flash.c |   11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
index d0732f5..81ac5d3 100644
--- a/drivers/mtd/cfi_flash.c
+++ b/drivers/mtd/cfi_flash.c
@@ -835,14 +835,19 @@ static int flash_write_cfiword (flash_info_t *
info, ulong dest,
 		break;
 	case CFI_CMDSET_AMD_EXTENDED:
 	case CFI_CMDSET_AMD_STANDARD:
-#ifdef CONFIG_FLASH_CFI_LEGACY
-	case CFI_CMDSET_AMD_LEGACY:
-#endif
 		sect = find_sector(info, dest);
 		flash_unlock_seq (info, sect);
 		flash_write_cmd (info, sect, info->addr_unlock1, AMD_CMD_WRITE);
 		sect_found = 1;
 		break;
+#ifdef CONFIG_FLASH_CFI_LEGACY
+	case CFI_CMDSET_AMD_LEGACY:
+		sect = find_sector(info, dest);
+		flash_unlock_seq (info, 0);
+		flash_write_cmd (info, 0, info->addr_unlock1, AMD_CMD_WRITE);
+		sect_found = 1;
+		break;
+#endif
 	}

 	switch (info->portwidth) {
-- 
1.6.3.3


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