From patchwork Thu Aug 7 12:47:21 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Kosina X-Patchwork-Id: 4690981 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id EF6159F373 for ; Thu, 7 Aug 2014 12:47:27 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2B6B1201C0 for ; Thu, 7 Aug 2014 12:47:27 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id D3EE2201B4 for ; Thu, 7 Aug 2014 12:47:25 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5231A6E021; Thu, 7 Aug 2014 05:47:25 -0700 (PDT) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mx2.suse.de (cantor2.suse.de [195.135.220.15]) by gabe.freedesktop.org (Postfix) with ESMTP id 7CD456E021 for ; Thu, 7 Aug 2014 05:47:23 -0700 (PDT) Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 2A1B9ABBB; Thu, 7 Aug 2014 12:47:22 +0000 (UTC) Date: Thu, 7 Aug 2014 14:47:21 +0200 (CEST) From: Jiri Kosina To: Pavel Machek In-Reply-To: <20140711192629.GA20015@amd.pavel.ucw.cz> Message-ID: References: <20140607120614.GB5309@amd.pavel.ucw.cz> <20140607231124.GA3611@amd.pavel.ucw.cz> <20140609102328.GA25332@amd.pavel.ucw.cz> <20140625223522.GA5923@xo-6d-61-c0.localdomain> <20140707083908.GE5821@phenom.ffwll.local> <20140711192629.GA20015@amd.pavel.ucw.cz> User-Agent: Alpine 2.00 (LNX 1167 2008-08-23) MIME-Version: 1.0 Cc: Linux-pm mailing list , intel-gfx , "Rafael J. Wysocki" , kernel list Subject: Re: [Intel-gfx] 3.15-rc: regression in suspend X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Spam-Status: No, score=-4.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On Fri, 11 Jul 2014, Pavel Machek wrote: > > > > Ok, so I have set up machines for ktest / autobisect, and found out that > > > > 3.16-rc1 no longer has that problem. Oh well, bisect would not be fun, > > > > anyway... > > > > > > I am still seeing the problem with 3.16-rc2. > > > > I'm confused now. Is the bisect result > > > > commit 773875bfb6737982903c42d1ee88cf60af80089c > > Author: Daniel Vetter > > Date: Mon Jan 27 10:00:30 2014 +0100 > > > > drm/i915: Don't set the 8to6 dither flag when not scaling > > > > now the culprit or not? Or do we have 2 different bugs at hand here? > > Three different issues, it seems. Two ring initialization problems, > one went away in 3.16 (for me), second did not (suspend for jikos), > third -- trivial issue with 8to6 dither. The patch below seems to finally cure the problem at my system; I've just attached it to freedesktop bugzilla, but sending it to this thread as well to hopefully get as much testing coverage by affected people as possible. I am going on with testing whether it really completely fixes the problem or just made it less likely. From: Jiri Kosina Subject: [PATCH] drm/i915: read HEAD register back in init_ring_common() to enforce ordering Withtout this, ring initialization fails reliabily during resume with [drm:init_ring_common] *ERROR* render ring initialization failed ctl 0001f001 head ffffff8804 tail 00000000 start 000e4000 Signed-off-by: Jiri Kosina --- drivers/gpu/drm/i915/intel_ringbuffer.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 279488a..7add7ee 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -517,6 +517,9 @@ static int init_ring_common(struct intel_engine_cs *ring) else ring_setup_phys_status_page(ring); + /* Enforce ordering by reading HEAD register back */ + I915_READ_HEAD(ring); + /* Initialize the ring. This must happen _after_ we've cleared the ring * registers with the above sequence (the readback of the HEAD registers * also enforces ordering), otherwise the hw might lose the new ring