[U-Boot] [PATCH 0/3] at91: atmel_nand: add PMECC(Programmable Multibit ECC controller) support

[Josh Wu]

Hi, Andreas

Thank you for the quick reply.

On 8/15/2012 3:50 PM, Andreas Bießmann wrote:
> Dear Josh Wu,
>
> On 15.08.2012 08:50, Josh Wu wrote:
>> Hi, Andreas
>>
>> Sorry, in these patches of current version, it still has a bug, which
>> will fail to write with PMECC, I will send out the v2 patch soon which
>> include this bug fix.
> Oups, sorry I had this patch series not on my list. Will review this or
> v2 these days.
> On first sight the first two in series are ok, the third one has style
> problems:
>
> ---8<---
> abiessmann at azuregos % ./tools/checkpatch.pl
> U-Boot-3-3-at91-atmel_nand-Update-driver-to-support-Programmable-Multibit-ECC-controller.patch
> WARNING: line over 80 characters
> ...
> total: 1 errors, 27 warnings, 787 lines checked
>
> NOTE: Ignored message types: COMPLEX_MACRO CONSIDER_KSTRTO MINMAX
> MULTISTATEMENT_MACRO_USE_DO_WHILE
>
> U-Boot-3-3-at91-atmel_nand-Update-driver-to-support-Programmable-Multibit-ECC-controller.patch
> has style problems, please review.
>
> If any of these errors are false positives, please report
> them to the maintainer, see CHECKPATCH in MAINTAINERS.
> --->8---
>
> I personally do not really care about the 80 char warning but please
> remove these for the sake of peace ;) and please have a look for the
> reported error.

sure, I will fix that. :)

> And the last, you should add at least one user of this feature. Isn't
> the lately applied at91sam9x5ek (is in u-boot-atmel/master and
> u-boot-arm/master) a perfect user for that?

you are right, The PMECC usage is for 9x5ek board.
I planed to push the PMECC support patches in 9x5 board in two part:
    one is this series, which only include nand flash driver changes. I 
thought those patches should be merged by u-boot mtd maintainer.
    Another part is some patches for 9x5 board file and config file 
which enable PMECC in 9x5ek board. Those patches are not sent out yet.

Now I think if you can merge all above patches to u-boot mainline, then 
maybe I can sent those patches together. What do you think about this?

>
>> On 8/9/2012 6:21 PM, Josh Wu wrote:
>>> This patch series will add PMECC support for atmel nand driver in u-boot.
>>>
>>> The driver patch is ported from kernel patch. The main different from
>>> kernel patch is
>>> the modification about registers access part. in this version it via a
>>> register structure to access.
> A question regarding linux driver. You say it is derived from the kernel
> driver, but I can not see PMECC stuff in kernel:

Sorry,  I am not make it clear about this. Actually, The PMECC stuff is 
not in v3.6-rc1 now, it is queued in kernel MTD maintainer's git tree: 
http://git.infradead.org/linux-mtd.git/commit/1c7b874d33b463f7150b1ab4617f000af9b327fd
Seems the maintainer missed the merge window of v3.6-rc1. I am not sure 
that can go into v3.6 or not. But I think it is not a bad idea to push 
those code into u-boot. :)

> ---8<---
> abiessmann at azuregos % git describe
> v3.6-rc1-355-gddf343f
> abiessmann at azuregos % diff -Nrupa drivers/mtd/nand/atmel_nand.c
> ../u-boot/drivers/mtd/nand/atmel_nand.c | diffstat
>   atmel_nand.c | 1231
> ++++++++++++++++++++++++++++++++++-------------------------
>   1 file changed, 720 insertions(+), 511 deletions(-)
> abiessmann at azuregos % grep -in pmecc drivers/mtd/nand/atmel_nand*
> abiessmann at azuregos %
> --->8---
>
> Which driver/patch do you mean?
>
>>> It is tested in atmel 9x5 series board.
> Unfortunately I can not test this driver cause I do only have older
> sam926x devices around.

If I send 9x5 board enable patches with nand PMECC patches together, I 
think maybe other people can test it in 9x5ed board.

>
> Best regards
>
> Andreas Bießmann
>
Best Regards,
Josh Wu