Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752372AbYANPYT (ORCPT ); Mon, 14 Jan 2008 10:24:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750824AbYANPYL (ORCPT ); Mon, 14 Jan 2008 10:24:11 -0500 Received: from mx1.redhat.com ([66.187.233.31]:56697 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750733AbYANPYK (ORCPT ); Mon, 14 Jan 2008 10:24:10 -0500 Message-ID: <478B7E62.9070700@redhat.com> Date: Mon, 14 Jan 2008 10:23:14 -0500 From: Tony Camuso Reply-To: tcamuso@redhat.com User-Agent: Thunderbird 2.0.0.9 (X11/20071031) MIME-Version: 1.0 To: Arjan van de Ven CC: Alan Cox , Ivan Kokshaysky , Greg KH , Matthew Wilcox , Linus Torvalds , Greg KH , linux-kernel@vger.kernel.org, Jeff Garzik , linux-pci@atrey.karlin.mff.cuni.cz, Benjamin Herrenschmidt , Martin Mares , Loic Prylli , Prarit Bhargava , "Chumbalkar, Nagananda" , "Schoeller, Patrick (Linux - Houston, TX)" , Bhavana Nagendra Subject: Re: [Patch v2] Make PCI extended config space (MMCONFIG) a driver opt-in References: <20080111213803.GS18741@parisc-linux.org> <20080111235856.GA16079@jurassic.park.msu.ru> <20080112002638.GA18710@kroah.com> <20080112144030.GA19279@jurassic.park.msu.ru> <20080112094557.71f5382a@laptopd505.fenrus.org> <20080112214911.GA20102@jurassic.park.msu.ru> <20080112150120.05f93768@laptopd505.fenrus.org> <47895767.3090503@redhat.com> <20080112164006.6f6f7bc2@laptopd505.fenrus.org> <47896B3B.2000108@redhat.com> <20080112204248.29abb1dd@laptopd505.fenrus.org> <478A075F.7010503@redhat.com> <20080113090311.0a9a1db5@laptopd505.fenrus.org> <478A8268.6020107@redhat.com> <20080114005434.48340f84@lxorguk.ukuu.org.uk> <20080113173331.617ac935@laptopd505.fenrus.org> <478AD713.8060204@redhat.com> <20080113210501.4584e4d2@laptopd505.fenrus.o! rg> <478B5D0D.7060808@redhat.com> <20080114064614.22081ff3@laptopd505.fenrus.org> In-Reply-To: <20080114064614.22081ff3@laptopd505.fenrus.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1311 Lines: 31 Arjan van de Ven wrote: > On Mon, 14 Jan 2008 08:01:01 -0500 > Tony Camuso wrote: >> >> If we're going to differentiate MMCONFIG from >> some other access mechanism, it only needs to be done at the >> Northbridge level. Devices are electrically ignorant of the protocol >> used between CPU and Northbridge to get the Northbridge to assert >> config cycles on the bus. > > Again this is about having systems that don't need extended config space not use it. At all. > The only way to do that is have the drivers say they need it, and not use it otherwise. > It has NOTHING to do with how things are wired up. It's pure a kernel level policy decision > about whether to use extended config space AT ALL. > The problem with compelling device drivers to determine the PCI config mechanism is that it must be forced upon arches that have no PCI configuration quirks or don't even use the same PCI config mechanisms as x86. I don't think that's a good policy. Better to confine arch-specific quirks to the arch-specific code whenever possible. -- 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/