Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753011AbdDMQU7 (ORCPT ); Thu, 13 Apr 2017 12:20:59 -0400 Received: from mga06.intel.com ([134.134.136.31]:5092 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751654AbdDMQU5 (ORCPT ); Thu, 13 Apr 2017 12:20:57 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.37,195,1488873600"; d="scan'208";a="73700374" Date: Thu, 13 Apr 2017 19:20:31 +0300 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Ilia Mirkin Cc: Alex Deucher , lkml , Maling list - DRI developers Subject: Re: KMS question Message-ID: <20170413162031.GW30290@intel.com> References: <2a39d6ca-afdd-bccf-264f-132736313d2b@pr.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2563 Lines: 60 On Thu, Apr 13, 2017 at 11:37:45AM -0400, Ilia Mirkin wrote: > On Thu, Apr 13, 2017 at 11:36 AM, Alex Deucher wrote: > > On Thu, Apr 13, 2017 at 11:03 AM, Boszormenyi Zoltan wrote: > >> 2017-04-13 16:05 keltez?ssel, Alex Deucher ?rta: > >>> > >>> On Thu, Apr 13, 2017 at 9:03 AM, Boszormenyi Zoltan wrote: > >>>> > >>>> Hi, > >>>> > >>>> how can I disable the behaviour in the KMS drivers > >>>> that enables all outputs at once? > >>>> > >>>> It is very annoying that on a POS machine with an > >>>> 1024x768 LVDS and a 800x480 secondary monitor (both built-in) > >>>> the KMS driver wakes up both. Then the framebuffer console > >>>> and plymouth use both screens, making the primary output > >>>> very odd with only the top-left part used by the boot splash. > >>>> > >>>> I would like the boot splash to be shown only on the primary > >>>> output at its full resolution instead of on all outputs using > >>>> the smallest common rectangle. > >>>> > >>>> Is there a kernel command line configuration that achieves this? > >>>> > >>>> The device in question uses the gma500 kernel driver but the same > >>>> behaviour is observed with the i915 and radeon drivers. > >>>> > >>> > >>> The problem is fbdev is not multi-head aware. The fbdev emulation in > >>> the KMS drivers attempts to light up all monitors so that something > >>> shows up on all heads. If you really want different per head > >>> configurations, you need to use the KMS API directly. As a > >>> workaround, you can use the kernel command line to disable the output > >>> you don't want to be lit up. See: > >>> https://wiki.archlinux.org/index.php/kernel_mode_setting > >>> for more info. basically add video=TV-1:d to disable the output in > >>> question. Replace TV-1 with whatever connector you want to disable. > >> > >> > >> I tried adding video=DVI-D-1:d to the kernel command line. > >> > >> The effect is while the second output is indeed disabled, the > >> framebuffer console still takes the second output's resolution > >> into account and the boot splash is still using only the top-left > >> 800x480 part of the 1024x768 primary screen. > >> > >> Also, the secondary screen got disabled also in X which is not desired. > >> Can I wake it up under X somehow? This device is using the modesetting > >> DDX driver. > > > > Can you enable it via randr? > > I think the video= based disable forces the connector to be disabled > irrevocably. # echo detect > /sys/class/drm//status -- Ville Syrj?l? Intel OTC