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Date: Thu, 8 Jul 2010 15:09:04 -0500
From: Scott Wood <scottwood@freescale.com>
To: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: [PATCH] arch/powerpc/lib/copy_32.S: Use alternate memcpy for
	MPC512x and MPC52xx
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On Thu, 8 Jul 2010 21:30:33 +0200
Segher Boessenkool <segher@kernel.crashing.org> wrote:

> > Actually, this is something which might need closer attention -
> > and maybe some support in the device tree indicating which read or  
> > write width a device can accept?
> 
> There already is "device-width"; the drivers never should use any
> other access width unless they *know* that will work.

Wouldn't you want to use "bank-width" instead?  "device-width" might
not even work if, say, you've got two 8-bit chips interleaved, feeding
into a bus controller in 16-bit mode that only accepts 16-bit accesses.

It would be nice to have a device tree property that can specify that
all access widths supported by the CPU will work, though.

-Scott