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Subject: Re: [RFC PATCH 2/2] mtd: nand: use nand_check_erased_ecc_chunk in
 default ECC read functions
To: Andrea Scian <rnd4@dave-tech.it>,
        Boris Brezillon <boris.brezillon@free-electrons.com>
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From: Richard Weinberger <richard@nod.at>
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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. :)

> 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