[U-Boot] [PATCH] MTD: atmel_nand: support for software BCH ECC

[Andreas Bießmann]

Dear Scott Wood,

On 04.09.13 21:44, Scott Wood wrote:
> On Wed, 2013-09-04 at 17:15 +0200, Andreas Bießmann wrote:
>> On 09/04/2013 02:46 PM, Bo Shen wrote:
>>> On 9/4/2013 8:30 PM, Andreas Bießmann wrote:
>>>>>> Yes, we need libbch.
>>>>>>
>>>>>> If we really want to enable software BCH support. It also need add
>>>>>> following two options in board configuration file.
>>>>>> ---8>---
>>>>>> #define CONFIG_NAND_ECC_BCH
>>>>>> #define CONFIG_BCH
>>>>>> ---<8---
>>>>>>
>>>>>> So, this patch give us option to enable software BCH.
>>>> got it. So the NAND_ECC_BCH is the adoption for the SW BCH correction in
>>>> mtd layer. I understand that this would be helpful for at91 SoC without
>>>> PMECC HW. But there is no user currently, so I hesitate to apply this.
>>>
>>> Frankly, there is no EK boards from Atmel use software BCH now, however,
>>> a lot of customers use NAND with 224 bytes OOB, can not use software
>>> ECC, they need use software BCH.
>>
>> I understand this. But it will be a piece of dead code until a user of
>> it would be submitted.
>>
>>> So, I think it is better to apply this patch. If it will break the rule
>>> of u-boot, then I think we can wait real user in u-boot need this and
>>> then apply this patch.
>>
>> I'd like to hear Scott's comment on that.
> 
> Is this for the benefit of out-of-tree boards, or for boards which will
> be submitted but haven't yet?
> 
> In the latter case, it could be submitted at the same time.  In the
> former case, of course we encourage the boards to be submitted, and we
> don't generally add code solely for the benefit of out-of-tree boards.  
> 
> In any case, this is minor enough that I don't care all that much.  If
> we ever get kconfig, then hopefully the "dead code" rules will relax to
> code which could be enabled through some legal config, rather than code
> which is enabled in some default config for a board.  Things like
> allyesconfig and randconfig could help with build test coverage.

I think this is a 'yes we take it'. Scott, would you pull it in or
should I do? Is it even that minor to pull it into 2013.10? It was
posted weeks after merge window closed.

Best regards

Andreas Bießmann