[U-Boot] [U-BOOT] cfi_flash.c fails to program NOR Flash SST39LF040

[Po-Yu Chuang]

Dear Stefan Roese,

2009/7/3 Stefan Roese <sr at denx.de>:
> Yes, I understand your problem and it needs to get fixed. But your original
> patch changed the unlock address not only for this "legacy" FLASH type but for
> all AMD type FLASH chips. And I'm not sure if this is correct. Meaning if the
> AMD/Spansion chips will accept these unlock addresses.
>
> Perhaps you could check some data-sheets (some older and more recent Spansion
> CFI chips) which unlock addresses should be used here.

After checked the data sheets of jedec flash currently supported in u-boot -

SST 39LF020
AMD AM29LV040B
SST 39LF040
ST Micro M29W040B
AMD AM29LV400BB
AMD AM29LV800BB

I found that the addresses to program a word of these chips are
related to 0 (not sector base).

And in flash_erase() in drivers/mtd/cfi_flash.c

			case CFI_CMDSET_AMD_STANDARD:
			case CFI_CMDSET_AMD_EXTENDED:
				flash_unlock_seq (info, sect);
				flash_write_cmd (info, sect,
						info->addr_unlock1,
						AMD_CMD_ERASE_START);
				flash_unlock_seq (info, sect);
				flash_write_cmd (info, sect, 0,
						 AMD_CMD_ERASE_SECTOR);
				break;
#ifdef CONFIG_FLASH_CFI_LEGACY
			case CFI_CMDSET_AMD_LEGACY:
				flash_unlock_seq (info, 0);
				flash_write_cmd (info, 0, info->addr_unlock1,
						AMD_CMD_ERASE_START);
				flash_unlock_seq (info, 0);
				flash_write_cmd (info, sect, 0,
						AMD_CMD_ERASE_SECTOR);
				break;
#endif

It look like CFI_CMDSET_AMD_LEGACY use base 0
CFI_CMDSET_AMD_STANDARD and CFI_CMDSET_AMD_EXTENDED use sector base
for erase.

It probably is the same case while programing a word.

The following patch might be feasible.
However, I don't have those chips for testing.

regards,
Po-Yu Chuang

---
 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