Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753411AbdDMPgt (ORCPT ); Thu, 13 Apr 2017 11:36:49 -0400 Received: from mail-yw0-f170.google.com ([209.85.161.170]:36822 "EHLO mail-yw0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753155AbdDMPgr (ORCPT ); Thu, 13 Apr 2017 11:36:47 -0400 MIME-Version: 1.0 In-Reply-To: References: <2a39d6ca-afdd-bccf-264f-132736313d2b@pr.hu> From: Alex Deucher Date: Thu, 13 Apr 2017 11:36:45 -0400 Message-ID: Subject: Re: KMS question To: Boszormenyi Zoltan Cc: lkml , Maling list - DRI developers Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id v3DFb0LU017288 Content-Length: 2113 Lines: 51 On Thu, Apr 13, 2017 at 11:03 AM, Boszormenyi Zoltan wrote: > 2017-04-13 16:05 keltezéssel, Alex Deucher írta: >> >> 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? Alex