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Subject: Re: mtd-utils/nandwrite: what if write fails?
From: Artem Bityutskiy <dedekind@infradead.org>
To: Ricard Wanderlof <ricard.wanderlof@axis.com>
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Date: Fri, 27 Oct 2006 17:13:05 +0300
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On Fri, 2006-10-27 at 15:07 +0200, Ricard Wanderlof wrote:
> I assume that the mtd block devices don't provide any bad block managemen=
t=20
> either? (Hm, one could imagine a device which when written to simply=20
> skipped bad blocks ... ?)
Yes. I personally have never used it because it is obviously very poor
FTL and is barely usable except for testing/debugging or such.

> A torture test would be nice too, but it's not really the same thing.=20
> Blocks can go bad with time, and when one actually does go bad, it has to=
=20
> be handled at that time.

I offer you to test it. Select an eraseblock, and erase it many times in
cycle and see what happens. It may be interesting. I can send you a test
module which does this.

> Another option would be to integrate erasure into nandwrite, so that it=20
> could erase blocks prior to writing them, to give a completely integrated=
=20
> utility. Writing to a non-erased (nand) flash is rather pointless anyway=20
> isn't it? Naturally, one would want to set limits for the erasure so that=
=20
> not the whole flash would have to be erased just to write a small image.

IMO be it makes sense to write a nice image flashing utility for this
instead from scratch.

--=20
Best regards,
Artem Bityutskiy (=D0=91=D0=B8=D1=82=D1=8E=D1=86=D0=BA=D0=B8=D0=B9 =D0=90=
=D1=80=D1=82=D1=91=D0=BC)