Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754842Ab0AZSf1 (ORCPT ); Tue, 26 Jan 2010 13:35:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754731Ab0AZSf0 (ORCPT ); Tue, 26 Jan 2010 13:35:26 -0500 Received: from outbound-mail-111.bluehost.com ([69.89.18.7]:56715 "HELO outbound-mail-111.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754577Ab0AZSfZ (ORCPT ); Tue, 26 Jan 2010 13:35:25 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=default; d=virtuousgeek.org; h=Received:Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References:X-Mailer:Mime-Version:Content-Type:Content-Transfer-Encoding:X-Identified-User; b=NPOFfoNpVXI/8BWaHNKep3CPrExJKw4thmiRzv6esMmmJOBRBH4r93kF/PSf0o+DTtzJsVBIySioSOxaFJeI6J0WmgXFmrqgf4zzHhk8H78btrc5dezQzRjB2J8HCgdk; Date: Tue, 26 Jan 2010 10:35:11 -0800 From: Jesse Barnes To: Yinghai Lu Cc: Linus Torvalds , Bjorn Helgaas , "Rafael J. Wysocki" , Jeff Garrett , Linux Kernel Mailing List , Kernel Testers List , Linux PCI , Myron Stowe , Matthew Garrett , Ingo Molnar Subject: Re: [Bug #15124] PCI host bridge windows ignored (works with pci=use_crs) Message-ID: <20100126103511.16781111@jbarnes-piketon> In-Reply-To: <4B5F32A9.7090105@kernel.org> References: <20100126071912.GA7543@jgarrett.org> <201001261348.59508.rjw@sisk.pl> <201001261032.37053.bjorn.helgaas@hp.com> <4B5F32A9.7090105@kernel.org> X-Mailer: Claws Mail 3.7.2 (GTK+ 2.18.3; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Identified-User: {10642:box514.bluehost.com:virtuous:virtuousgeek.org} {sentby:smtp auth 75.111.28.251 authed with jbarnes@virtuousgeek.org} Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2217 Lines: 48 On Tue, 26 Jan 2010 10:21:29 -0800 Yinghai Lu wrote: > On 01/26/2010 10:16 AM, Linus Torvalds wrote: > > > > > > On Tue, 26 Jan 2010, Bjorn Helgaas wrote: > >> > >> which IS big enough, and we know the bridge is in fact forwarding the > >> [mem 0xd0000000-0xdfffffff 64bit pref] region, because the Radeon works > >> when Jeff boots with "pci=use_crs". > > > > I bet it's a subtractive decode thing. Sure, it could be just another > > undocumented range register (does anybody have the datasheet for that > > thing?) but Intel tends to often have subtractive decode. > > > > That system in question has three PCI express root ports, but two of them > > have IO and memory disabled according to the lspci info. So maybe it's as > > simple as that "I/O Hub PCI Express Root Port 7" just catching anything > > that nobody else does, and the single IOH host chip doing the same? > > > >> I think we should remove intel_bus.c before .33. It's breaking boxes > >> and we don't know how to fix it. Even if we do find out how to fix it, > >> I think we should move toward using _CRS instead, because that's what > >> Windows uses and it's an easy way for the firmware to tell us about > >> platform quirks. > > > > I suspect that for 33 it is indeed best to just revert. But somebody is > > bound to have information on how the actual hardware works. Yinghai? > > I have asked intel if there is any bit that could be enabled the routing. > there is no info about for their documentations. I could probably dig something up in our confidential database, but this is the main problem with intel_bus.c. It'll always be behind with _CRS provides. Sure _CRS may be wrong sometimes, but it'll always work well enough to bring Windows up, so we ought not to ignore it. The underlying problems with our _CRS support still aren't fixed though, so switching that on for 2.6.33 isn't an option. -- Jesse Barnes, Intel Open Source Technology Center -- 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/