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Date: Wed, 29 Jan 2014 11:29:59 +0100
From: boris brezillon <b.brezillon@overkiz.com>
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To: Brian Norris <computersforpeace@gmail.com>
Subject: Re: [RFC PATCH 1/9] mtd: nand: retrieve ECC requirements from Hynix
 READ ID byte 4
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Cc: devicetree@vger.kernel.org, Russell King <linux@arm.linux.org.uk>,
 linux-doc@vger.kernel.org, dev@linux-sunxi.org, linux-kernel@vger.kernel.org,
 Huang Shijie <b32955@freescale.com>, linux-mtd@lists.infradead.org,
 Rob Landley <rob@landley.net>, Grant Likely <grant.likely@linaro.org>,
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Hello Brian,

On 23/01/2014 02:49, Brian Norris wrote:
> + Huang
>
> Hi Boris,
>
> On Wed, Jan 08, 2014 at 03:21:56PM +0100, Boris BREZILLON wrote:
>> The Hynix nand flashes store their ECC requirements in byte 4 of its id
>> (returned on READ ID command).
>>
>> Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
> I haven't verified yet (perhaps Huang can confirm?), but this may be
> similar to a patch Huang submitted recently. In his case, we found that
> this table is actually quite unreliable and is likely hard to maintain.

You mean these bytes are not reliable within the whole Hynix LP (Large Page)
NAND product line ?

>
> Why do you need this ECC information, for my reference?

Because the NAND flash available on the cubietruck board does not 
support the
ONFI standard, and I thought this could be a option to retrieve the ECC 
strength
requirements.

Anyway, I added a new helper function to retrieve ecc informations from 
device
tree (I'll post it in the 2nd version of this series). We'll see if this 
approach is
accepted...

>
> Brian