Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754119AbaGKUgk (ORCPT ); Fri, 11 Jul 2014 16:36:40 -0400 Received: from mga02.intel.com ([134.134.136.20]:62130 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751088AbaGKUgj convert rfc822-to-8bit (ORCPT ); Fri, 11 Jul 2014 16:36:39 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,645,1400050800"; d="scan'208";a="571903347" From: "Tian, Kevin" To: Konrad Rzeszutek Wilk , Paolo Bonzini , "xen-devel@lists.xensource.com" , "airlied@linux.ie" , "intel-gfx@lists.freedesktop.org" , "linux-kernel@vger.kernel.org" , "qemu-devel@nongnu.org" , "dri-devel@lists.freedesktop.org" , "Chen, Tiejun" , "Kay, Allen M" Subject: RE: [Xen-devel] [Intel-gfx] [RFC][PATCH] gpu:drm:i915:intel_detect_pch: back to check devfn instead of check class type Thread-Topic: [Xen-devel] [Intel-gfx] [RFC][PATCH] gpu:drm:i915:intel_detect_pch: back to check devfn instead of check class type Thread-Index: AQHPmhLtddRUcHA0YU245zC1cQ8wppuZzrXAgAF9phOAAAppIA== Date: Fri, 11 Jul 2014 20:30:59 +0000 Message-ID: References: <53A42DAA.80406@redhat.com> <53A692F9.3060200@intel.com> <53AA70C0.2000806@redhat.com> <20140707144917.GZ5821@phenom.ffwll.local> <53BAB569.5000709@redhat.com> <20140707175402.GS5821@phenom.ffwll.local> <53BADFC6.9060101@redhat.com> <20140707184006.GU5821@phenom.ffwll.local> <20140711062956.GP17271@phenom.ffwll.local> <20140711194206.GI23257@laptop.dumpdata.com> In-Reply-To: <20140711194206.GI23257@laptop.dumpdata.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > From: Konrad Rzeszutek Wilk [mailto:konrad.wilk@oracle.com] > Sent: Friday, July 11, 2014 12:42 PM > > On Fri, Jul 11, 2014 at 08:29:56AM +0200, Daniel Vetter wrote: > > On Thu, Jul 10, 2014 at 09:08:24PM +0000, Tian, Kevin wrote: > > > actually I'm curious whether it's still necessary to __detect__ PCH. Could > > > we assume a 1:1 mapping between GPU and PCH, e.g. BDW already hard > > > code the knowledge: > > > > > > } else if (IS_BROADWELL(dev)) { > > > dev_priv->pch_type = PCH_LPT; > > > dev_priv->pch_id = > > > > INTEL_PCH_LPT_LP_DEVICE_ID_TYPE; > > > DRM_DEBUG_KMS("This is Broadwell, > assuming " > > > "LynxPoint LP PCH\n"); > > > > > > Or if there is real usage on non-fixed mapping (not majority), could it be a > > > better option to have fixed mapping as a fallback instead of leaving as > > > PCH_NONE? Then even when Qemu doesn't provide a special tweaked > PCH, > > > the majority case just works. > > > > I guess we can do it, at least I haven't seen any strange combinations in > > the wild outside of Intel ... > > How big is the QA matrix for this? Would it make sense to just > include the latest hardware (say going two generations back) > and ignore the older one? suppose minimal or no QA effort on bare metal, if we only conservatively change the fallback path which is today not supposed to function with PCH_NONE. so it's only same amount of QA effort as whatever else is proposed in this passthru upstreaming task. I agree no need to cover older model, possibly just snb, ivb and hsw, but will leave Tiejun to answer the overall goal. Thanks Kevin -- 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/