From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754679Ab2D2Whw (ORCPT ); Sun, 29 Apr 2012 18:37:52 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:59583 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754625Ab2D2Whu (ORCPT ); Sun, 29 Apr 2012 18:37:50 -0400 Date: Sun, 29 Apr 2012 15:37:44 -0700 From: Dmitry Torokhov To: Nick Bowler Cc: Alex Deucher , Ben Skeggs , Martin Peres , Linus Torvalds , Linux Kernel Mailing List , dri-devel@lists.freedesktop.org Subject: Re: Linux 3.4-rc4 Message-ID: <20120429223744.GA19382@core.coreip.homeip.net> References: <20120422164023.GA32342@elliptictech.com> <20120423000554.GA893@elliptictech.com> <20120423024558.GD13840@phenom.dumpdata.com> <20120424010345.GA30674@elliptictech.com> <20120425013537.GA11959@elliptictech.com> <1335322574.1821.8.camel@nisroch> <1335504021.5311.0.camel@nisroch> <20120428003928.GA16805@elliptictech.com> <20120428153350.GA19561@elliptictech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20120428153350.GA19561@elliptictech.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Apr 28, 2012 at 11:33:50AM -0400, Nick Bowler wrote: > On 2012-04-28 02:19 -0400, Alex Deucher wrote: > > On Fri, Apr 27, 2012 at 8:39 PM, Nick Bowler wrote: > > > Hi Ben, > > > > > > On 2012-04-27 15:20 +1000, Ben Skeggs wrote: > > >> Does this patch help you at all? > > >> > > >> http://cgit.freedesktop.org/nouveau/linux-2.6/commit/?id=a3a285f17867f0018de798b5ee85731ec1268305 > > > > > > Yes.  I cherry-picked this patch on top of Linus' master (3.4-rc4+) and > > > this appears to solve the "black screen on VGA" problem described in the > > > original report.  Thanks! > > > > > > Unfortunately, that's not the end of my VGA-related regressions. :( > > > > > > While tracking down the black screen issue, I've been having the monitor > > > directly connected to the video card the whole time, but now when I'm > > > connected through my KVM switch (an IOGear GCS1804), it appears that > > > something's going wrong with reading the EDID, because the available > > > modes are all screwed up (both console and X decide they want to drive > > > the display at 1024x768).  Here's the output of xrandr on 3.2.15: > > > > > >  % xrandr > > >  Screen 1: minimum 320 x 200, current 1600 x 1200, maximum 4096 x 4096 > > >  VGA-1 connected 1600x1200+0+0 (normal left inverted right x axis y axis) 352mm x 264mm > > >     1600x1200      75.0*+   70.0     65.0     60.0 > > >     1280x1024      85.0 +   75.0     60.0 > > >     1920x1440      60.0 > > >     1856x1392      60.0 > > >     1792x1344      60.0 > > >     1920x1200      74.9     59.9 > > >     1680x1050      84.9     74.9     60.0 > > >     1400x1050      85.0     74.9     60.0 > > >     1440x900       84.8     75.0     59.9 > > >     1280x960       85.0     60.0 > > >     1360x768       60.0 > > >     1280x800       84.9     74.9     59.8 > > >     1152x864       75.0 > > >     1280x768       84.8     74.9     59.9 > > >     1024x768       85.0     75.1     75.0     70.1     60.0     43.5     43.5 > > >     832x624        74.6 > > >     800x600        85.1     72.2     75.0     60.3     56.2 > > >     848x480        60.0 > > >     640x480        85.0     75.0     72.8     72.8     66.7     60.0     59.9 > > >     720x400        85.0     87.8     70.1 > > >     640x400        85.1 > > >     640x350        85.1 > > >     320x200       165.1 > > > > > > And on 3.4-rc4+ (with your patch cherry-picked): > > > > > >  % xrandr > > >  Screen 1: minimum 320 x 200, current 1024 x 768, maximum 4096 x 4096 > > >  VGA-1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm > > >     1024x768       60.0* > > >     800x600        60.3     56.2 > > >     848x480        60.0 > > >     640x480        59.9 > > >     320x200       165.1 > > > > > > Running xrandr on 3.4-rc4+ also causes the screen to go black for a > > > second when it does not on 3.2.15.  It also causes several messages of > > > the form > > > > > >  [drm] nouveau 0000:01:00.0: Load detected on output B > > > > > > to be logged.  Also, looking at /sys/class/drm/card0-VGA-1/edid I see > > > that it is empty on 3.4-rc4+ and it is correct on 3.2.15.  Things seem > > > to work OK when the KVM is not involved. > > > > Were you ever able to fetch a EDID with the KVM involved? KVMs are > > notorious for not connecting the ddc pins. > > Yes, it works on 3.2.15 as described above. I have the same (or similar) KVM (not in the office at the moment) and I can confirm that with newer kernels EDID fecthing in flaky. It's 50/50 if EDED retrieval succeeds or if it fails with: Apr 26 13:06:57 dtor-d630 kernel: [13464.936336] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 208 Apr 26 13:06:57 dtor-d630 kernel: [13464.955317] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 208 Apr 26 13:06:57 dtor-d630 kernel: [13464.973879] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 208 Apr 27 09:13:03 dtor-d630 kernel: [44602.087659] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 208 Apr 27 09:13:03 dtor-d630 kernel: [44602.107147] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 208 Apr 27 09:13:03 dtor-d630 kernel: [44602.126908] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 208 Apr 27 09:13:03 dtor-d630 kernel: [44602.146277] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 208 Apr 27 09:13:03 dtor-d630 kernel: [44602.297659] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 208 Apr 27 09:13:03 dtor-d630 kernel: [44602.317063] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 208 Earlier kernels were able to retrieve EDEDs reliably. This is with: [ 1.678392] [drm] nouveau 0000:01:00.0: Detected an NV50 generation card (0x086b00a2) Thanks. -- Dmitry