[i915G] Low resolution mode set from non-existent VGA connection

This is for the case when it goes wrong. The diff to the previous file probably reveals something about what goes wrong:

$ diff Xorg.0.log.old.2001FP Xorg.0.log.2001FP
23c23
< (==) Log file: "/var/log/Xorg.0.log", Time: Mon Sep 22 14:08:17 2008
---
> (==) Log file: "/var/log/Xorg.0.log", Time: Mon Sep 22 14:08:41 2008
413a414,415
> (II) intel(0): I2C device "CRTDDC_A:ddc2" registered at address 0xA0.
> (II) intel(0): I2C device "CRTDDC_A:ddc2" removed.
418c420
< (II) intel(0): Output VGA disconnected
---
> (II) intel(0): Output VGA connected
419a422
> (II) intel(0): Output VGA using initial mode 1280x800
491,493c494
< drmOpenDevice: open result is -1, (No such device or address)
< drmOpenDevice: open result is -1, (No such device or address)
< drmOpenDevice: Open failed
---
> drmOpenDevice: open result is 8, (OK)
495,497c496
< drmOpenDevice: open result is -1, (No such device or address)
< drmOpenDevice: open result is -1, (No such device or address)
< drmOpenDevice: Open failed
---
> drmOpenDevice: open result is 8, (OK)
503d501
< (II) [drm] loaded kernel module for "i915" driver.
563,566c561,564
< (II) intel(0): Pipe B is off
< (II) intel(0): Display plane B is now disabled and connected to pipe B.
< (II) intel(0): Output VGA is connected to pipe none
< (II) intel(0): Output TMDS-1 is connected to pipe A
---
> (II) intel(0): Pipe B is on
> (II) intel(0): Display plane B is now enabled and connected to pipe B.
> (II) intel(0): Output VGA is connected to pipe A
> (II) intel(0): Output TMDS-1 is connected to pipe B
662a661
> (II) AIGLX: Suspending AIGLX clients for VT switch
669,671d667
< (II) intel(0): [drm] removed 1 reserved context for kernel
< (II) intel(0): [drm] unmapping 8192 bytes of SAREA 0xf8cd2000 at 0xb7a54000
< (II) intel(0): [drm] Closed DRM master.

I just tested the intrepid-alpha6 LiveCD. The problem has changed slightly there, the resolution is sometimes set to 1152x864 instead of the correct 1600x1200. But now there is no difference between the "logical" resolution and the actual resolution. This is reflected in Xorg.0.log as the same resolution in the lines

(II) intel(0): Output VGA using initial mode 1152x864
(II) intel(0): Output TMDS-1 using initial mode 1152x864

that had different resolution in Hardy.

During the test run now, it first came up with 1152x864, then on logout and login, it changed to 1600x1200, opposite order of what i usually get for Hardy.

To exclude hardware failure, I have tested the Hardy 8.04 LiveCD on two more identical computers (Dell Optiplex SX280 Ultra Small Form Factor), with the same results.

I noticed the similarity to the symptoms for the "Ignore TV Output Quirk" at https://wiki.ubuntu.com/X/Quirks . While doing this directly didn't work, I used VGA instead of TV to disable to VGA output:

In xorg.conf:

Section "Device"
        ...
        Option "Monitor-VGA" "VGA"
EndSection

and the new section:

Section "Monitor"
        Identifier "VGA"
        Option "Ignore" "True"
EndSection

and it worked. Of course the problem with this is that connecting via a VGA cable doesn't work anymore (No Screens found, and it falls back to low-res VESA).

Output of xrandr when the problem is present:
$ xrandr
Screen 0: minimum 320 x 200, current 1600 x 1200, maximum 1600 x 1600
VGA disconnected 1280x800+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
TMDS-1 connected 1600x1200+0+0 (normal left inverted right x axis y axis) 367mm x 275mm
   1600x1200 60.0*+ 59.9
   1280x1024 75.0 59.9
   1152x864 74.8
   1024x768 75.1 60.0
   800x600 75.0 60.3
   640x480 75.0 60.0
   720x400 70.1
  1280x800 (0x4d) 83.5MHz
        h: width 1280 start 1344 end 1480 total 1680 skew 0 clock 49.7KHz
        v: height 800 start 801 end 804 total 828 clock 60.0Hz

I had stored these two outputs when the problem was not present, and only discovered later that they were different:
$ xrandr
Screen 0: minimum 320 x 200, current 1600 x 1200, maximum 1600 x 1600
VGA connected (normal left inverted right x axis y axis)
   1280x800 60.0
   1280x768 60.0
   1024x768 60.0
   800x600 60.3
   640x480 59.9
TMDS-1 connected 1600x1200+0+0 (normal left inverted right x axis y axis) 367mm x 275mm
   1600x1200 60.0*+ 59.9
   1280x1024 75.0 59.9
   1152x864 74.8
   1024x768 75.1 60.0
   800x600 75.0 60.3
   640x480 75.0 60.0
   720x400 70.1

$ xrandr
Screen 0: minimum 320 x 200, current 1600 x 1200, maximum 1600 x 1600
VGA disconnected (normal left inverted right x axis y axis)
TMDS-1 connected 1600x1200+0+0 (normal left inverted right x axis y axis) 367mm x 275mm
   1600x1200 60.0*+ 59.9
   1280x1024 75.0 59.9
   1152x864 74.8
   1024x768 75.1 60.0
   800x600 75.0 60.3
   640x480 75.0 60.0
   720x400 70.1

(trying again, I am reproducing the second one)

For intrepid alpha 6 LiveCD the output of xrandr is the following:

When resolution is 1600x1200 (correct):
Screen 0: minimum 320 x 200, current 1600 x 1200, maximum 1680 x 1680
VGA disconnected (normal left inverted right x axis y axis)
TMDS-1 connected 1600x1200+0+0 (normal left inverted right x axis y axis) 367mm x 275mm
   1600x1200 60.0*+ 60.0
   1680x1050 60.0
   1600x1024 60.2
   1400x1050 70.0 60.0
   1280x1024 75.0 60.0 60.0
   1440x900 59.9
   1280x960 60.0
   1360x768 59.8
   1152x864 75.0 75.0 75.0 70.0 60.0
   1024x768 75.1 75.0 70.1 60.0
   832x624 74.6
   800x600 72.2 75.0 60.3 56.2
   640x480 75.0 72.8 75.0 60.0 59.9
   720x400 70.1

When resolution is 1152x864 (wrong):
Screen 0: minimum 320 x 200, current 1152 x 864, maximum 1680 x 1680
VGA disconnected 1152x864+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
TMDS-1 connected 1152x864+0+0 (normal left inverted right x axis y axis) 367mm x 275mm
   1600x1200 60.0 + 60.0
   1680x1050 60.0
   1600x1024 60.2
   1400x1050 70.0 60.0
   1280x1024 75.0 60.0 60.0
   1440x900 59.9
   1280x960 60.0
   1360x768 59.8
   1152x864 75.0 75.0 75.0 70.0 60.0*
   1024x768 75.1 75.0 70.1 60.0
   832x624 74.6
   800x600 72.2 75.0 60.3 56.2
   640x480 75.0 72.8 75.0 60.0 59.9
   720x400 70.1

I found that this was also reported in the Debian bug tracker and added the corresponding bug (# 498262). The hardware and problem seems to be exactly the same, except that for the debian reporter it seems to happen every time. His symptoms are the same as I have for Hardy, but the underlying cause for both Hardy and Intrepid is the same: The driver thinks there is a VGA display connected when in fact there isn't and sets a mode for that display which has lower resolution than the connected DVI display.

I tried an Intrepid LiveCD today and installed xserver-xorg-video-intel_2.5.1~git20081113_i386.deb and libdrm2_2.4.1-0ubuntu1+ppa4_i386.deb from Tom Jaeger's PPA (https://launchpad.net/~thjaeger/+archive). The behaviour was still the same as for the regular Intrepid (including alpha) packages. Nevertheless, I attach the corresponding Xorg.0.conf.

Note: I didn't know if I had to reload the drm kernel module for this to work, so I killed gdm, did an `rmmod i915`, `rmmod drm` and then I started X with /usr/bin/Xorg, since rebooting with a LiveCD isn't an option.

The behaviour in Jaunty alpha-2 is the same as for Intrepid, except
the for the 7-8 times I logged out and in again the "Good" case never
happened, so it may be more consistent now. I'm attaching the relevant
files as captured from a LiveCD.

I find it funny that while Xorg.0.log reports VGA to be connected:
(II) intel(0): Output VGA connected
...
(II) intel(0): Output configuration:
(II) intel(0): Pipe A is on
(II) intel(0): Display plane A is now enabled and connected to pipe A.
..
(II) intel(0): Output VGA is connected to pipe A
xrandr reports it to be disconnected:
VGA disconnected 1152x864+0+0 (normal left inverted right x axis y
axis) 0mm x 0mm

This bug report has become a bit messy over time, so I'm wondering if
it perhaps would be an idea to close it and file a new and cleaned up
one.

> The behaviour in Jaunty alpha-2 is the same as for Intrepid, except
> the for the 7-8 times I logged out and in again the "Good" case never
> happened, so it may be more consistent now.

I said this too early. It still goes well every now and then. Next
time I started the X-server the good case was back and it's still
random.

Moreover, in the good case, the output of xrandr is actually dynamic
-- it usually shows "VGA disconnected", but every now and then is
shows "VGA connected". When running xrandr 50 times, it was
disconnected 38 times and connected 12 times. Every time it writes
some lines to Xorg.0.log, which differs slightly depending on whether
xrandr shows disconnected or connected. The four possible cases are
attached, 3195-disconnected-diff.txt or b567-disconnected-diff.txt
would come when xrandr shows disconnected, and one of the two others
when it shows connected. The only difference between the files is the
presence of two blocks of I2C messages. The appearance of the second
block happens when xrandr shows VGA connected. The first block may or
may not appear in both cases.

Could it be that the state of some register fluctuates and that the
resolution of the X-server depends on the state of this register when
the X-server is started?

Hi Geir,

Wow, this sounds weird. This bug should go upstream to bugs.freedesktop.org - would you mind filing it upstream there? You've collected enough data.

The one other thing you *might* want to do before upstreaming is to test against Tormod's 2.6.99.x intel driver on the xorg-edgers page: https://edge.launchpad.net/~xorg-edgers/+archive/ppa

I have reported this upstream: http://bugs.freedesktop.org/show_bug.cgi?id=20463

Looks like there's a patch upstream that fixes it, not yet pushed. Presumably this will be included in 2.8, and maybe 2.7.2.

It hit git-master at freedesktop.org today: http://cgit.freedesktop.org/xorg/driver/xf86-video-intel/commit/?id=88f766be008008d76c150e3ac16f09d4ecbb6d53 . Hopefully it also ends up in 2.7.2.

This bug was fixed in the package xserver-xorg-video-intel - 2:2.7.99.1+git20090602.ec2fde7c-0ubuntu4

---------------
xserver-xorg-video-intel (2:2.7.99.1+git20090602.ec2fde7c-0ubuntu4) karmic; urgency=low

  * Add 122_wait_for_vblank_to_sub_border_color.patch: Wait for next
    Vblank to substitue border color for Color info. Otherwise, this can
    result in incorrect resolution detection due to phantom VGA port
    on i915 and earlier. Cherrypick from upstream's main branch.
    (LP: #273306)

 -- Bryce Harrington <email address hidden> Sat, 27 Jun 2009 16:15:14 -0700

Hello, Im Grungekid
I'm New to linux and Ubuntu, so heres my problem:-
I did a clean install of Ubuntu Jaunty 9.4 on my Fujitsu Seiemns Amilo D-8820 and according to the OS there is no screen, it wont detect the monitor, i'm using an ATI Radeon Graphics card... anyone able to help me?

On Sat, Oct 24, 2009 at 2:51 PM, <email address hidden>
<email address hidden> wrote:
> Hello, Im Grungekid
> I'm New to linux and Ubuntu, so heres my problem:-
> I did a clean install of Ubuntu Jaunty 9.4  on my Fujitsu Seiemns Amilo D-8820 and according to the OS there is no screen, it wont detect the monitor, i'm using an ATI Radeon Graphics card... anyone able to help me?

Grungekid, I'm sure you can get some help at http://ubuntuforums.org.
At bugs.launchpad.net we focus on improving ubuntu by getting rid of
bugs, and this particular bug report is completely unrelated to your
problem.

That being said, you seem to have a valid bug and we would appreciate
if you would report it. However at this time, we need to know that
this is still a problem in the latest development version. If you
install the release candidate now (or the final version soon), you can
report the problem to the package xserver-xorg-video-ati. See
https://launchpad.net/ubuntu/+bugs?field.tag=no-screens for a few bug
reports for similar problems. Make sure you attach the files
/var/log/Xorg.0.log, /etc/X11/xorg.conf (if it exists), and the
output of the two commands `lspci -vvnn` and `dmesg`.

If you want to read more two good starting points are:
https://wiki.ubuntu.com/X
https://wiki.ubuntu.com/Bugs