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Subject: Re: [RFC PATCH 2/2] mtd: nand: use nand_check_erased_ecc_chunk in
 default ECC read functions
To: Richard Weinberger <richard@nod.at>,
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From: Andrea Scian <rnd4@dave-tech.it>
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Date: Thu, 6 Aug 2015 06:28:45 +0200
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Il 04/08/2015 09:21, Richard Weinberger ha scritto:
> Andrea,
>
> Am 04.08.2015 um 09:02 schrieb Andrea Scian:
>>> I'm not sure whether introducing a read-before-write check is the best solution.
>>> At least we need hard numbers for slow/old SLC NANDs too.
>>
>> We can enable the feature only for MLC, AFAIK it has not been required for old SLC ;-)
>
> I think this needs more discussion.
>
> Boris, Brian, will you be at Embedded Linux Conference Europe in Dublin?
> Maybe we can discuss these issues (data retention, ff-checks, etc...) in person and
 > figure out where to address them.
> I really want to avoid ad-hoc solutions. :)

Maybe I'll be at ELCE this year too
I'll be glad to meet all of you in person and participate to this 
discussion. :)

It will be nice if also some silicon vendor would like to participate. I 
know that someone from micron is actively following us on this ML, but I 
don't really know if there's someone here in Europe. :)

>
>> Thanks.
>> In your opinion, enabling chk_io is correct to rough estimate the overhead
 >> or does it enable too much checks?
>
> You mean the other checks bedside of self_check_write()? You can comment them out
 > for your tests.
>
> Thanks,
> //richard
>

Kind Regards,

-- 

Andrea SCIAN

DAVE Embedded Systems