From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jani Nikula Subject: Re: [PATCH] drm/i915/vlv: reset VLV media force wake request register Date: Fri, 09 May 2014 21:54:55 +0300 Message-ID: <87vbten5og.fsf@intel.com> References: <1399639278-30941-1-git-send-email-jani.nikula@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id F13F46E68E for ; Fri, 9 May 2014 11:54:59 -0700 (PDT) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Darren Hart , intel-gfx@lists.freedesktop.org, Imre Deak List-Id: intel-gfx@lists.freedesktop.org On Fri, 09 May 2014, Darren Hart wrote: > On 5/9/14, 5:41, "Jani Nikula" wrote: > >>Media force wake get hangs the machine when the system is booted without >>displays attached. The assumption is that (at least some versions of) >>the firmware has skipped some initialization in that case. >> >>Empirical evidence suggests we need to reset the media force wake >>request register in addition to the render one to avoid hangs. >> >>Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=75895 >>Reported-by: Imre Deak >>Reported-by: Darren Hart >>Cc: stable@vger.kernel.org >>Signed-off-by: Jani Nikula > > Applied to 3.14.2 and tested on MinnowBoardMax A0 hardware (BayTrail-I, > Atom E3825). > > * With no display connected, the boot no longer hangs and DRM prints > sensible messages during boot: > [ 5.968837] [drm] GMBUS [i915 gmbus vga] timed out, falling back to bit > banging on pin 2 > [ 5.988037] i915 0000:00:02.0: No connectors reported connected with > modes > [ 5.995744] [drm] Cannot find any crtc or sizes - going 1024x768 > [ 6.004716] fbcon: inteldrmfb (fb0) is primary device > [ 6.013066] Console: switching to colour frame buffer device 128x48 > [ 6.034147] i915 0000:00:02.0: fb0: inteldrmfb frame buffer device > [ 6.041168] i915 0000:00:02.0: registered panic notifier > [ 6.049820] ACPI: Video Device [GFX0] (multi-head: yes rom: no post: > no) > [ 6.058788] acpi device:30: registered as cooling_device3 > [ 6.065111] input: Video Bus as > /devices/LNXSYSTM:00/device:00/PNP0A08:00/LNXVIDEO:00/input/input4 > [ 6.075370] [drm] Initialized i915 1.6.0 20080730 for 0000:00:02.0 on > minor 0 > > > * If a display is subsequently connected and X is restarted, it behaves as > expected. > > * Booting with a display connected continue to work as expected. > > Tested-by: Darren Hart > > Thank you very much Jani! Pushed to -fixes. Thanks for testing, Darren, and thanks for review, Mika. BR, Jani. > > -- > Darren Hart Open Source Technology Center > darren.hart@intel.com Intel Corporation > > > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Jani Nikula, Intel Open Source Technology Center