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Subject: Re: jffs2 and unaligned access
From: David Woodhouse <dwmw2@infradead.org>
To: Sascha Hauer <s.hauer@pengutronix.de>
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Date: Wed, 07 May 2008 11:53:49 +0100
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On Wed, 2008-05-07 at 12:27 +0200, Sascha Hauer wrote:
> memcpy_from/to_io() use word aligned accesses on the io side of memory.
> The MPC5200 local plus bus where our flashes are connected does not
> allow unaligned accesses, so we have to use the io versions of memcpy.

But this region of flash is marked as suitable for execute-in-place,
otherwise the point() function wouldn't be working to give a direct
pointer to it. It sounds like we shouldn't be allowing that.

Which in turn means that perhaps we should have a property in the
corresponding node in the device-tree which indicates that it's not
suitable for direct access?

-- 
dwmw2