From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965241Ab1GOJJu (ORCPT ); Fri, 15 Jul 2011 05:09:50 -0400 Received: from gate.crashing.org ([63.228.1.57]:58039 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964982Ab1GOJJt (ORCPT ); Fri, 15 Jul 2011 05:09:49 -0400 Subject: Re: Dropped IRQ disables Radeon 3D From: Benjamin Herrenschmidt To: Michael Witten Cc: linux-kernel@vger.kernel.org, Arnuschky In-Reply-To: <0fe54f4a77b64475b9e6041d9ef5772b-mfwitten@gmail.com> References: <0fe54f4a77b64475b9e6041d9ef5772b-mfwitten@gmail.com> Content-Type: text/plain; charset="UTF-8" Date: Fri, 15 Jul 2011 19:09:44 +1000 Message-ID: <1310720984.4968.313.camel@pasglop> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2011-07-15 at 08:20 +0000, Michael Witten wrote: > > Arnuschky wrote to me about this related Debian bug report: > > Fri, 2010-06-18 10:21:05 +0000 > http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=586312 > > I popped over to #radeon on freenode where user agd5f told me to > try the following on the kernel command line: > > pci=nomsi > > After reading about MSIs and the requisite CONFIG_* settings, I > realized that I didn't even have MSI support in the kernel anyway. > Then agd5f suggested the following patches by Benjamin Herrenschmidt > might be of help: Another problem I noticed is some cards, when not using MSIs, still seem to shoot an MSI with whatever value was last programmed into the MSI configuration space. Can you check with lspci -vv if there's a non-0 value in there ? It -could- be that your get bogus MSIs. Cheers, Ben. > > http://lists.freedesktop.org/archives/dri-devel/2011-July/012980.html > > http://lists.freedesktop.org/archives/dri-devel/2011-July/012981.html > > the latter of which fixes a syncronization bug on systems that use > non-MSI IRQs (presumably pin-based IRQs) for the radeon device/driver. > > For my system, I decided to enable MSI/MSI-X support by building > Linux with the following configuration variables set: > > CONFIG_PCI=y > CONFIG_X86_LOCAL_APIC=y > CONFIG_X86_IO_APIC=y > CONFIG_PCI_MSI=y > > and making sure I get the following: > > $ dmesg | grep MSI | grep radeon > radeon 0000:01:00.0: irq 42 for MSI/MSI-X > radeon 0000:01:00.0: radeon: using MSI. > > I'm not sure if this will avoid the problem, but it sure seems like > a good bet. > >