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Subject: Re: [PATCH] mtd: omap2-nand: avoid unaligned DMA accesses, fall
 back on prefetch method
From: Artem Bityutskiy <dedekind1@gmail.com>
To: "Arnout Vandecappelle (Essensium/Mind)" <arnout@mind.be>
Date: Fri, 28 Sep 2012 06:35:45 +0300
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Cc: Tony Lindgren <tony@atomide.com>, David Woodhouse <dwmw2@infradead.org>,
 linux-omap@vger.kernel.org, linux-mtd@lists.infradead.org,
 Sven Krauss <sven.krauss@web.de>
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On Thu, 2012-09-20 at 17:44 +0200, Arnout Vandecappelle (Essensium/Mind)
wrote:
> It's difficult to reproduce the error, because the buffers are
> aligned most of the time.

Can you just take one of the mtd tests (e.g., mtd_speedtest), amend it a
little and make sure it uses unaligned buffers?

> Perhaps a better method is to fetch the first few unaligned bytes
> with the prefetch method, and then continue with DMA.  However,
> since it's hard to force an unaligned buffer, it's also hard to
> test that this method works.

Yes, this would be a lot cleaner.

--=20
Best Regards,
Artem Bityutskiy

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