Cannot erase nand flash

[Josh Boyer]

On 6/26/06, Steve Finney <saf76 at earthlink.net> wrote:
>
> >Date: Mon, 26 Jun 2006 10:52:43 +0200
> >From: peter.hosten at rwth-aachen.de
>
> > Unfortunately the mtd-util
> >(flash_eraseall, mtd_debug) is not able to erase the NAND-Flash. I get the
> >error  "./flash_eraseall: /dev/mtd3: MTD Erase failure: Input/output error"
> >(see below)
>
> >I also dumped the NAND Flash ( see below); may it be possible that it does
> >not work because of the OBB data ( OOB Data: 00 00 00 00 00 00 00 00 00 00
> >00 00 00 00 00 00) ?
>
> I have seen that error with some versions of mtd-utils when the partition contains a
> bad block, and your dumped OOB would be interpreted as a bad block
> (no 0xFF in byte 5). But, in fact, the flash may have been successfully erased, and Linux
> works reasonably well with bad blocks, so you may be able to just ignore
> the "error".

The tool could be made to check each block to see if it's bad first
before erasing.  Then it would print a nice informative:

Block %d is bad, skipping

instead of the misleading error you get now.

josh