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Date: Thu, 30 Jul 2015 09:29:14 +0200
From: Boris Brezillon <boris.brezillon@free-electrons.com>
To: Hans de Goede <hdegoede@redhat.com>, Brian Norris
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Cc: David Woodhouse <dwmw2@infradead.org>, linux-mtd@lists.infradead.org,
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Subject: Re: [PATCH 2/4] mtd: nand: nand_decode_ext_id(): Fill in ecc
 strength and size for Samsung
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Hi,

On Wed, 29 Jul 2015 19:53:52 +0200
Hans de Goede <hdegoede@redhat.com> wrote:

> On some nand controllers with hw-ecc the controller code wants to know the
> ecc strength and size and having these as 0, 0 is not accepted.
> 
> Specifying these in devicetree is possible but undesirable as the nand
> may be different in different production runs of the same board, so it
> is better to get this info from the nand id where possible.
> 
> This commit adds code to read the ecc strength and size from the nand for
> Samsung extended-id nands. This code is based on the info for the 5th
> id byte in the datasheets for the following Samsung nands: K9GAG08U0E,
> K9GAG08U0F, K9GAG08X0D, K9GBG08U0A, K9GBG08U0B. These all use these bits
> in the exact same way.

Okay, that's the one I'm not sure about. If that's really the case,
and Samsung is actually using the same layout for all its chips, we
should be good, but as I already stated in the other thread, this was
not the case for Hynix chips.

Best Regards,

Boris

-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com