UBI use subpage and verify fail when write on nandflash

[Jon Povey]

Brian Norris wrote:
> On Tue, Apr 17, 2012 at 7:19 AM, b w <wdjjwb at gmail.com> wrote:
>> Hello,
>>    Use linux 2.6.32,ARM,nandflash(support subpage),config
>> CONFIG_MTD_NAND_VERIFY_WRITE. UBI attach fail on empty flash.I found
>> when UBI write VID header to the second subpage of eraseblock,will
>> call function "nand_write_page",this function write a whole page(i
>> think the page size is 2048),the unset bit of the buf is filled with
>> 0xff,after write,
>>
>> #ifdef CONFIG_MTD_NAND_VERIFY_WRITE
>>        /* Send command to read back the data */
>>        chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
>>
>>        if (chip->verify_buf(mtd, buf, mtd->writesize))
>>                return -EIO;
>> #endif
>>
>> now,the buf for verify is not equal to the buf which write,because
>> the buf which read from flash contains EC header ?
>>
>> I found there is topic also mention subpage:
>>
> http://lists.infradead.org/pipermail/linux-mtd/2010-September/
> 031822.html
>
> Hmm, not sure if this is exactly the same issue, but it is related.
> It's worth CC'ing Jon to see if he pursued this at all.

I have just carried on happily using my hack. Don't have the time to
work on a proper fix, sorry.

Hack attached if it is of interest, apologies for the format,
blame my email client. This is against roughly mainline 3.0

--
Jon Povey
jon.povey at racelogic.co.uk

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