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Subject: Re: [Qemu-devel] Re: [PATCH 1/6] Make config space accessor host
	bus trapable
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Date: Tue, 05 Jan 2010 07:10:58 +1100
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Blue Swirl <blauwirbel@gmail.com>, Isaku Yamahata <yamahata@valinux.co.jp>, Alexander Graf <agraf@suse.de>, Aurelien Jarno <aurelien@aurel32.net>, QEMU Developers <qemu-devel@nongnu.org>

On Mon, 2010-01-04 at 13:07 +0200, Michael S. Tsirkin wrote:
> BTW, I think we really should think about the right way to address the
> swap/noswap issue without using a preprocessor. Maybe make pci host
> bridge explicitly specify whether to swap bytes?  How about adding a
> field in PCIHostState to make it do this? 

No, this is a non issue if you get your design right. Just abstract out
the reference to a device in a struct like Alex is proposing and have
the host bridge specific code fill that up appropriately. I don't see
why there would be any need for swapping and in any case, this should go
away once the host bridge code knows how to interpret the write to
whatever config access registers it exposes.

Ben.