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Date: Tue, 28 Jul 2009 15:35:19 +0100
From: Ian Molton <ian@mnementh.co.uk>
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To: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Subject: Re: abuse of nand_correct_data in tmio_nand driver
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Atsushi Nemoto wrote:
> On Tue, 28 Jul 2009 14:57:05 +0100, Ian molton <spyro@f2s.com> wrote:
>>>> The current nand_correct_data() can be used for ecc.bytes = 3 case
>>>> only.  The tmio_nand driver uses ecc.bytes = 6.
>>> IIRC, tmio_nand driver accesses two ecc "sectors" at once, so this is
>>> most probably ok. I'll look into it though, when I have some time.
>> Are we really the only chip that does this?
> 
> TXx9 NDFMC can read 6 byte ECC (for two 256 byte sectors) at a time.
> I will try to see if doing it increase performance or not.

Cool,

If theres more than one chip that can do this, I think the change should 
go in the core mmc code.