From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Garzik <jgarzik@redhat.com>
Subject: Re: [PATCH] aic94xx: driver assertion in non-x86 BIOS env
Date: Wed, 1 Mar 2006 16:39:03 -0500
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To: "Tarte, Robert" <Robert_Tarte@adaptec.com>
Cc: Matthew Wilcox <matthew@wil.cx>, Jeff Garzik <jgarzik@pobox.com>, Mike Anderson <andmike@us.ibm.com>, James Bottomley <James.Bottomley@SteelEye.com>, linux-scsi@vger.kernel.org

On Wed, Mar 01, 2006 at 01:22:56PM -0800, Tarte, Robert wrote:
> > From: Matthew Wilcox [mailto:matthew@wil.cx]
> > You're saying that you do an 8-byte non-DMA write to an address
> > that's congruent to 4 mod 8?  Based on briefly skimming the internal
> > documentation for zx1, I'd say you're invoking undefined behaviour.

> Thanks for the confirmation.  Internal documentation for zx1?  Where can
> I locate this?  Thanks in advance.

Overall, I would say that -- for any arch, not just zx1 -- you need to
make sure your write[bwlq]() calls are always naturally aligned in the
given register space.  Anything else invites problems.

It sounds like you are already on the right track, though, converting
non-aligned writeq() to write[bwl]...

	Jeff