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Date: Fri, 17 Jun 2011 16:34:42 -0500
From: Scott Wood <scottwood@freescale.com>
To: "Matthew L. Creech" <mlcreech@gmail.com>
Subject: Re: NAND BBT corruption on MPC83xx
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On Fri, 17 Jun 2011 16:54:27 -0400
"Matthew L. Creech" <mlcreech@gmail.com> wrote:

> Hi, I posted this on the Linux-MTD list but haven't gotten any hits.
> Since it looks like it could be MPC83xx-specific, I'm reposting here.
> Rick Johnson noted a problem in fsl_elbc_nand.c back in May which
> might be related:
> 
> http://lists.infradead.org/pipermail/linux-mtd/2011-May/035372.html

It seems that the generic code always passes -1 with PAGEPROG, and only
provides the actual page address on SEQIN.

I don't think the ECC readback is needed, and the fact that it looks like
it has always been broken would seem to confirm that.  It's broken in
other ways, too -- it assumes a particular ECC layout.  Let's get rid of it.

As for the corruption, could it be degradation from repeated reads of that
one page?

> More info on this board:
> - MPC 8313 SoC
> - 1GB Samsung NAND flash (K9K8G08U0B)
> - Linux 2.6.31
> - U-Boot 2009.06

Hmm, 2.6.31... it's probably not related to this problem, but you
should cherry pick b3a70f0bc32d1b70584bcaa6019fa4260b0da92e and
476459a6cf46d20ec73d9b211f3894ced5f9871e.

-Scott