[PATCH v2] mtd: rawnand: arasan: Include ECC syndrome along with in-band data while checking for ECC failure

[Miquel Raynal]

On Wed, 2023-09-27 at 05:56:21 UTC, Amit Kumar Mahapatra wrote:
> Following an ECC failure condition upon page reads, we shall distinguish
> between a real ECC failure and an empty page. This is handled with a call
> to nand_check_erased_ecc_chunk() which looks at the data and counts the
> number of bits which are not 'ones'. If we get less zeros than the ECC
> strength, we assume the page was erased and we are in the presence of
> natural bitflips. Otherwise, if we are above, we assume some data was
> written and the ECC engine could not recover it all, so we report an ECC
> failure.
> 
> In order for this logic to be as close as the reality as we can (this is
> already a simplified condition but we can hardly be more precise), we
> should check all the data that is covered by the ECC step not only the
> in-band data, so we should also include the ECC syndrome in the check.
> 
> Fixes: 88ffef1b65cf ("mtd: rawnand: arasan: Support the hardware BCH ECC engine")
> Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra at amd.com>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next, thanks.

Miquel