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Subject: Re: [linux-sunxi] Re: [PATCH 2/4] mtd: nand: nand_decode_ext_id():
 Fill in ecc strength and size for Samsung
To: boris.brezillon@free-electrons.com,
 Brian Norris <computersforpeace@gmail.com>
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Cc: David Woodhouse <dwmw2@infradead.org>, linux-mtd@lists.infradead.org,
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From: Hans de Goede <hdegoede@redhat.com>
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Date: Thu, 30 Jul 2015 14:19:03 +0200
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Hi,

On 30-07-15 09:29, Boris Brezillon wrote:
> 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.

The list of datasheets I checked is longer then the one used to write
the other samsung code which is setting equally important properties.

Regards,

Hans