Subject: [PATCH v2 3/4] mtd: mxc_nand: fix truncate of unaligned oob copying

From: [email-masked] (Baruch Siach)
Date: Wed, 13 May 2015 08:12:02 +0300

Hi Uwe,

On Fri, May 08, 2015 at 09:24:32AM +0200, Uwe Kleine-K?nig wrote:
> On Sun, May 03, 2015 at 10:18:53AM +0300, Baruch Siach wrote:
> > Copy to/from oob io area might not be aligned to 4 bytes. When 8 bit ECC is
> > used, the buffer size is 26. Add memcpy16_{to,from}io, and use them to avoid
> > truncating the buffer. Prefer memcpy32_{to,from}io when the buffer is properly
> > aligned for better performance.
> Did you measure this performance difference? I doubt it's worth the
> complexity given that we're talking about buffers with a size of up to
> 26 bytes.

We'll need both memcpy16_{to,from}io and memcpy32_{to,from}io anyway. So by 
"complexity" you refer to the additional alignment check and memcpy32 
fallback?

baruch

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