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Date: Wed, 20 Sep 2006 09:27:11 +1000
From: Paul Mackerras <paulus@samba.org>
To: linas@austin.ibm.com (Linas Vepstas)
Subject: Re: Fw: [PATCH] Remove powerpc specific parts of 3c509 driver
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Linas Vepstas writes:

> The rest of this patch might indeed be correct, but the above comment 
> bothers me. The "ns" versions of routines are supposed to be
> non-byte-swapped versions of the insl/outsl routines (which would
> byte-swap on big-endian archs such as powerpc.)

If it were true that in/outsw and in/outsl were actually used to
transfer arrays of 16-bit data items or 32-bit data items to/from an
I/O device, I would agree with you, but they aren't.  They are
universally used to transfer arrays of bytes, with the optimization of
doing so 2 or 4 bytes at a time.  That is why in/outsw and in/outsl
don't (and shouldn't) do byte swapping.

Paul.