[PATCH v3 1/2] mtd: spi-nor: add support to non-uniform SFDP SPI NOR flash memories

On Wed, 17 Oct 2018 09:10:45 +0200
Boris Brezillon [off-list ref] wrote:

On Wed, 17 Oct 2018 09:07:24 +0200
Boris Brezillon [off-list ref] wrote:

quoted

On Wed, 17 Oct 2018 02:07:43 +0000
Yogesh Narayan Gaur [off-list ref] wrote:
  

quoted

quoted

Actually there is no entry of s25fs512s in current spi-nor.c file.
For my connected flash part, jedec ID read points to s25fl512s. I
have asked my board team to confirm the name of exact connected flash
part. When I check the data sheet of s25fs512s, it also points to the
same Jedec ID information. { "s25fl512s",  INFO(0x010220, 0x4d00, 256
* 1024, 256, ....}

But as stated earlier, if I skip reading SFDP or read using 1-1-1
protocol then read are always correct. For 1-4-4 protocol read are
wrong and on further debugging found that Read code of 0x6C is being
send as opcode instead of 0xEC.

If I revert this patch, reads are working fine.    

Can you try with the following patch?
  

Hm, nevermind. The problem is actually not related to 4B vs non-4B mode
but 1-1-4 vs 1-4-4 modes.

Can you add traces in this loop [1] to see which features are flagged
as supported and which ones are not.

[1]https://elixir.bootlin.com/linux/v4.19-rc8/source/drivers/mtd/spi-nor/spi-nor.c#L2259