Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756114Ab2FNOFm (ORCPT ); Thu, 14 Jun 2012 10:05:42 -0400 Received: from mail-qc0-f174.google.com ([209.85.216.174]:51081 "EHLO mail-qc0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756017Ab2FNOFl (ORCPT ); Thu, 14 Jun 2012 10:05:41 -0400 MIME-Version: 1.0 X-Originating-IP: [178.83.130.250] In-Reply-To: References: <4FD9E69A.4090708@cwi.nl> Date: Thu, 14 Jun 2012 16:05:40 +0200 Message-ID: Subject: Re: [3.4 regression] [bisected] DisplayPort fails to come on From: Daniel Vetter To: Dave Airlie Cc: "Wouter M. Koolen" , intergalactic.anonymous@gmail.com, len.brown@intel.com, "linux-kernel@vger.kernel.org" , dri-devel , "Barnes, Jesse" , "Wilson, Chris" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1347 Lines: 37 On Thu, Jun 14, 2012 at 4:00 PM, Dave Airlie wrote: > On Thu, Jun 14, 2012 at 2:26 PM, Wouter M. Koolen > wrote: > cc'ing Daniel. > >> Hi Igor and Len, >> >> When I cold boot 3.4 on my laptop the second monitor attached to the >> displayport stays blank. It works fine with 3.3.8 and earlier. >> >> I get two error messages in dmesg: >> >> kernel: video: probe of LNXVIDEO:00 failed with error -5 >> >> kernel: [drm:intel_dp_complete_link_train] *ERROR* failed to train DP, >> aborting >> >> When I warm boot 3.4 after running kernel 3.3.8 first, only the first >> message appears and the display works fine. Ok, the second message is actually the one explaining the black screen. Can you please boot with drm.debug=0xe added to your kernel cmdline and attach the full dmesg, so we know a bit what your display hw looks like? Also, please redo the bisect if possible (with coldboots) and hunt for the black screen/the "failed to train DP" message. Thanks, Daniel -- Daniel Vetter daniel.vetter@ffwll.ch - +41 (0) 79 365 57 48 - http://blog.ffwll.ch -- 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/