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Date: Wed, 11 Nov 2009 09:49:24 -0500
From: Josh Boyer <jwboyer@linux.vnet.ibm.com>
To: Richard =?iso-8859-1?Q?R=F6jfors?= <richard.rojfors@mocean-labs.com>
Subject: Re: [PATCH 2/4] xilinx_spi: Switch to iomem functions and support
	little endian.
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Cc: spi-devel-general@lists.sourceforge.net,
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On Wed, Nov 11, 2009 at 03:38:34PM +0100, Richard Röjfors wrote:
>This patch changes the out_(be)(8|16|32) and in_(be)(8|16|32) calls to iowrite(8|16|32)
>and ioread(8|16|32). This to be able to build on platforms not supporting the in/out calls
>for instance x86.
>
>Support is also added for little endian writes. In some systems the registers should be
>accessed little endian rather than big endian.

I wonder if you should make the endianness a config option.  Right now you
have a conditional check for every read and write.  Does that impact
performance at all?

josh