From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758347Ab1KVUvv (ORCPT ); Tue, 22 Nov 2011 15:51:51 -0500 Received: from cavan.codon.org.uk ([93.93.128.6]:37336 "EHLO cavan.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756192Ab1KVUvu (ORCPT ); Tue, 22 Nov 2011 15:51:50 -0500 Date: Tue, 22 Nov 2011 20:51:45 +0000 From: Matthew Garrett To: Eugeni Dodonov Cc: Keith Packard , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH] drm/i915: By default, enable RC6 on IVB and SNB when reasonable Message-ID: <20111122205145.GA7206@srcf.ucam.org> References: <1321684889-18691-1-git-send-email-keithp@keithp.com> <20111122201531.GD5547@srcf.ucam.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: mjg59@cavan.codon.org.uk X-SA-Exim-Scanned: No (on cavan.codon.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 22, 2011 at 06:46:21PM -0200, Eugeni Dodonov wrote: > On Tue, Nov 22, 2011 at 18:15, Matthew Garrett wrote: > > > On Fri, Nov 18, 2011 at 10:41:29PM -0800, Keith Packard wrote: > > > > > + /* > > > + * Only enable RC6 if all dma remapping is disabled, or if > > > + * there's no iommu present in the machine. > > > + */ > > > + if (INTEL_INFO(dev)->gen == 6) > > > + return no_iommu || dmar_disabled; > > > > So the user has to choose between 5W of power saving or having dmar? And > > we default to giving them dmar? > > > From the latest investigations, it is either this, or random gpu hangs and > crashes when both are enabled :(. So blacklist dmar on sandybridge. The power saving is going to be more important for most users. -- Matthew Garrett | mjg59@srcf.ucam.org