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Date: Fri, 28 Oct 2011 13:51:27 +0200
From: Matthieu CASTET <matthieu.castet@parrot.com>
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To: Javier Martinez Canillas <martinez.javier@gmail.com>
Subject: Re: [RFC] Change ECC algorithm from userspace
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Cc: Enric Balletbo i Serra <eballetbo@iseebcn.com>,
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Javier Martinez Canillas a écrit :
> On Fri, Oct 28, 2011 at 12:30 PM, Matthieu CASTET
> <matthieu.castet@parrot.com> wrote:
>> PS : note that some OMAP ROM support a better protection than Hamming (but the
>> details are not public AFAIK)
>>
>> From OMAP34xx Multimedia Device, Silicon Revision 3.1.x, public version :
>>
>> Pages can contain errors caused by memory alteration. To correct these errors,
>> the ROM code uses ECC,
>> based on Hamming codes for SLC NAND and BCH (Bose, Ray-Chaudhuri, Hocquenghem)
>> code for
>> multilevel cell (MLC) devices. The computed ECC is compared to ECC stored in the
>> spare area of the
>> corresponding page. If there are uncorrectable errors, the ROM code returns with
>> FAIL.
>>
>
> Yes I've read that on the DM3730 TRM but as far as I understand only
> applies to MLC devices, but ours is SLC.
>
It also works on SLC devices. We are using it on micron slc that need 4 bits ECC.


Matthieu