Forwarding this bug from Ubuntu reporter Joe Barnett: http://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+bug/915408 [Problem] i have an external monitor (1920x1200 resolution) that, when set to 1920x1080 resolution (native resolution of laptop display), garbles the screen as seen in the screenshot below. The problem doesn't happen using the catalyst driver. https://bugs.launchpad.net/lightdm-gtk-greeter/+bug/813566/+attachment/2221015/+files/2011-07-20_07-51-28_83.jpg ProblemType: BugDistroRelease: Ubuntu 11.10 Package: xorg 1:7.6+7ubuntu7 ProcVersionSignature: Ubuntu 3.0.0-15.25-generic 3.0.13 Uname: Linux 3.0.0-15-generic x86_64 .tmp.unity.support.test.0: ApportVersion: 1.23-0ubuntu4 Architecture: amd64 CompizPlugins: [core,bailer,detection,composite,opengl,decor,mousepoll,vpswitch,regex,animation,snap,expo,move,compiztoolbox,place,grid,imgpng,gnomecompat,wall,ezoom,workarounds,staticswitcher,resize,fade,unitymtgrabhandles,scale,session,unityshell] CompositorRunning: None Date: Thu Jan 12 07:42:25 2012 DistUpgraded: Log time: 2011-07-13 10:07:59.371965 DistroCodename: oneiric DistroVariant: ubuntu ExtraDebuggingInterest: Yes, whatever it takes to get this fixed in Ubuntu GraphicsCard: ATI Technologies Inc Broadway PRO [Mobility Radeon HD 5800 Series] [1002:68a1] (prog-if 00 [VGA controller]) Subsystem: Hewlett-Packard Company Device [103c:1522]InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Release Candidate amd64 (20100419.1) MachineType: Hewlett-Packard HP ENVY 15 Notebook PC ProcEnviron: PATH=(custom, user) LANG=en_US.UTF-8ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.0.0-15-generic root=UUID=639dc488-e095-42a4-8c1f-ffb1a9299e1c ro crashkernel=384M-2G:64M,2G-:128M quiet splash vt.handoff=7SourcePackage: xorg UpgradeStatus: Upgraded to oneiric on 2011-07-13 (182 days ago) dmi.bios.date: 04/23/2010 dmi.bios.vendor: Hewlett-Packard dmi.bios.version: F.26 dmi.board.asset.tag: Base Board Asset Tag dmi.board.name: 1522 dmi.board.vendor: Hewlett-Packard dmi.board.version: 36.34 dmi.chassis.type: 10 dmi.chassis.vendor: Hewlett-Packard dmi.chassis.version: N/A dmi.modalias: dmi:bvnHewlett-Packard:bvrF.26:bd04/23/2010:svnHewlett-Packard:pnHPENVY15NotebookPC:pvr048F110000241920001530000:rvnHewlett-Packard:rn1522:rvr36.34:cvnHewlett-Packard:ct10:cvrN/A: dmi.product.name: HP ENVY 15 Notebook PC dmi.product.version: 048F110000241920001530000 dmi.sys.vendor: Hewlett-Packard version.compiz: compiz 1:0.9.6+bzr20110929-0ubuntu6 version.ia32-libs: ia32-libs 20090808ubuntu26 version.libdrm2: libdrm2 2.4.26-1ubuntu1 version.libgl1-mesa-dri: libgl1-mesa-dri 7.11-0ubuntu3 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 7.11-0ubuntu3 version.xserver-xorg: xserver-xorg 1:7.6+7ubuntu7 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.6.0-1ubuntu13 version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20110811.g93fc084-0ubuntu1 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.15.901-1ubuntu2.1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110411+8378443-1
Created attachment 55541 [details] BootDmesg.txt
Created attachment 55542 [details] CurrentDmesg.txt
Created attachment 55543 [details] XorgLog.txt
The problem is the modeline from your monitor for the 1920x1080 mode is greater than 165 Mhz which is the current cut off for single link mode in the driver: (II) RADEON(0): Modeline "1920x1080"x60.0 172.78 1920 2040 2248 2576 1080 1081 1084 1118 -hsync +vsync (67.1 kHz) It should work if you specify a modeline with a lower clock E.g., Modeline "1920x1080R" 138.50 1920 1968 2000 2080 1080 1083 1088 1111 +hsync -vsync
Created attachment 55557 [details] [review] possible fix This patch against drm-next or Linus git should fix the issue.
confirmed that the following sequence displays a non-garbled 1920x1080 display on the external monitor: # xrandr --newmode "1920x1080R" 138.50 1920 1968 2000 2080 1080 1083 1088 1111 +hsync -vsync # xrandr --addmode HDMI-0 1920x1080R # xrandr 1920x1080R
A patch referencing this bug report has been merged in Linux v3.3-rc2: commit 9aa59993e226af94088adaee993eb8cfd33ae295 Author: Alex Deucher <alexander.deucher@amd.com> Date: Fri Jan 20 15:03:30 2012 -0500 drm/radeon/kms: refine TMDS dual link checks
I've tested against a kernel with this patch, as well as mainline kernel (both built by ubuntu kernel team), and am still seeing the same behavior. So seems like this change doesn't fix the issue.
Created attachment 58148 [details] [review] fix This patch should fix it. Your chip is limited to 165 Mhz single link tmds. The mode you are trying to set is >165 Mhz. With this patch applied the mode should be properly rejected by the driver.
A patch referencing this bug report has been merged in Linux v3.3-rc7: commit 38aa4a568ba4c3ccba83e862a01e3e60e3b811ee Author: Alex Deucher <alexander.deucher@amd.com> Date: Wed Mar 7 19:05:01 2012 -0500 drm/radeon/kms: fix hdmi duallink checks
Original reporter noted fix released in later kernel version 3.3.
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