Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261350AbVCPTGC (ORCPT ); Wed, 16 Mar 2005 14:06:02 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262733AbVCPTF6 (ORCPT ); Wed, 16 Mar 2005 14:05:58 -0500 Received: from mta2.cl.cam.ac.uk ([128.232.0.14]:17024 "EHLO mta2.cl.cam.ac.uk") by vger.kernel.org with ESMTP id S261350AbVCPTFf (ORCPT ); Wed, 16 Mar 2005 14:05:35 -0500 In-Reply-To: <200503161042.03886.jbarnes@engr.sgi.com> References: <20050316181042.GA26788@infradead.org> <521a4568db3e955cb245d10aaba2d3ce@cl.cam.ac.uk> <200503161042.03886.jbarnes@engr.sgi.com> Mime-Version: 1.0 (Apple Message framework v619.2) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: Content-Transfer-Encoding: 7bit Cc: akpm@osdl.org, Ian.Pratt@cl.cam.ac.uk, linux-kernel@vger.kernel.org, Rik van Riel , kurt@garloff.de, Christoph Hellwig , Christian.Limpach@cl.cam.ac.uk From: Keir Fraser Subject: Re: [PATCH] Xen/i386 cleanups - AGP bus/phys cleanups Date: Wed, 16 Mar 2005 19:08:27 +0000 To: Jesse Barnes X-Mailer: Apple Mail (2.619.2) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1103 Lines: 30 On 16 Mar 2005, at 18:42, Jesse Barnes wrote: >> The AGP driver is only configurable for ppc32, alpha, x86, x86_64 and >> ia64, all of which have virt_to_bus. > > Yeah, but that doesn't mean it makes sense on all those platforms. The > biggest problem with virt_to_bus (well, depending on who you talk to) > is that > it can't handle systems where the address translation must be done > differently depending on *which* bus we're getting a bus address for. > Not > sure what makes sense in this case though... is the DMA mapping > interface > appropriate? I think that makes sense. How much code refactoring is needed to make use of it, though? Certainly it will work for Xen and it sounds better than virt_to_bus/bus_to_virt, if someone will cook up the alternative patch. Otherwise, virt_to_bus seems better than the status quo. :-) -- Keir - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/