Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934601AbXJSUVk (ORCPT ); Fri, 19 Oct 2007 16:21:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760442AbXJSUVb (ORCPT ); Fri, 19 Oct 2007 16:21:31 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:38260 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759478AbXJSUVa (ORCPT ); Fri, 19 Oct 2007 16:21:30 -0400 Message-ID: <471911BE.2000405@garzik.org> Date: Fri, 19 Oct 2007 16:21:18 -0400 From: Jeff Garzik User-Agent: Thunderbird 2.0.0.5 (X11/20070727) MIME-Version: 1.0 To: Linas Vepstas CC: Shane Huang , davem@davemloft.net, gregkh@suse.de, htejun@gmail.com, brice.goglin@gmail.com, david.gaarenstroom@gmail.com, linux-kernel@vger.kernel.org, linux-pci@atrey.karlin.mff.cuni.cz, shane.huang@amd.com, linux-ide@vger.kernel.org, Brice Goglin Subject: Re: [patch] PCI: disable MSI on more ATI NorthBridges References: <20071019195749.GK29903@austin.ibm.com> In-Reply-To: <20071019195749.GK29903@austin.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.4 (----) X-Spam-Report: SpamAssassin version 3.1.9 on srv5.dvmed.net summary: Content analysis details: (-4.4 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1387 Lines: 39 Linas Vepstas wrote: > On Fri, Oct 19, 2007 at 09:17:23PM +0800, Shane Huang wrote: >> Since we have little experience on PCI and MSI here, we had to try to > > As someone else pointed out, AMD should have *lots* of people with > pci and msi experience on the payroll. (Folks here buy AMD-designed > pci chips ...) > >> ONLY >> comment out the pci_intx() call in drivers/ata/ahci.c >> My system can boot up too with MSI enabled! >> >> So does it mean that the root cause is our SB700 SATA controller >> has a hardware bug where setting INTX_DISABLE in the PCI COMMAND >> register masks MSI interrupts too? > > That's what it sounds like, to me. > >> And what is the software solution or workaround? > > Not sure. Sounds like the device driver needs a quirk for this part. Take a look at tg3.c net driver change 2fbe43f6f631dd7ce19fb1499d6164a5bdb34568 which is a similar situation. However, it may turn out that removing the pci_intx() stuff as a general rule is easier than quirking these devices, if enough of them turn out to have this hardware bug. The tg3.c change should illustrate how to fix immediately, though. Jeff - 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/