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Date: Tue, 12 Jan 2010 10:35:22 -0500
From: Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>
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Subject: [Qemu-devel] Re: [PATCH 0/1] nand: Support random data reads.
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To: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
Cc: qemu-devel@nongnu.org

Edgar E. Iglesias wrote:
> As promised this is a resend of a patch I posted 2008-12-12.
>   
Thanks.
> At some point linux MTD started using random data reads and my NAND
> boards stopped working. This patch fixed the issue.
>
> I received a comment regarding sequential reads that cross page boundaries.
> Those won't work but they don't work without the patch either so IMO that
> can be addressed with follow-up patches.
>   
I share you opinion.
> Would be great if someone with access to guests for other NAND boards could
> try this out. Even better with something else than linux guests.
>   
For what it's worth, I have tried this on an ARM-based guest running 
Linux and it fixed my problem. Note that this (emulated) board 
integrates a fairly evolved NAND flash controller that takes over most 
flash device operations. The accesses made to the emulated NAND flash 
device are then not necessarily the same as would have been done by the 
stock MTD subsystem.

Also tested with u-boot integrating a dumbed-down version of the 
aforementioned driver.


jh