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From: Dan Malek <dan@embeddededge.com>
Date: Thu, 8 Sep 2005 09:56:52 -0400
To: Paul Mackerras <paulus@samba.org>
Cc: linux-ppc-embedded <linuxppc-embedded@ozlabs.org>
Subject: Re: [PATCH] add big endian version of ld_/st_ IO access macros and
	convert main 8xx code to use it
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On Sep 8, 2005, at 12:27 AM, Paul Mackerras wrote:

> Given how long it takes to access I/O devices, I don't believe an
> extra instruction or two is going to make a measurable difference.

That's kind of true.  However, the access to the CPM is nearly
instruction speed, except in the case when you actually use a
real IO register (like a GPIO on a port), then it's a little slower.


	-- Dan