On drm-next (RC3) or stock karmic kernels, the 1024x768 mode is missing from LVDS1. This is on a Dell Latitude X1 which used to be able to use at least modes 1280x768, 1024x768, 800x600 and 640x480 on Jaunty and before.
Screen 0: minimum 320 x 200, current 1920 x 1968, maximum 2048 x 2048
VGA1 connected 1920x1200+0+0 (normal left inverted right x axis y axis) 519mm x 324mm
1280x1024 75.0 60.0
1024x768 75.1 60.0
800x600 75.0 60.3
640x480 75.0 60.0
LVDS1 connected 1280x768+304+1200 (normal left inverted right x axis y axis) 264mm x 159mm
TV1 disconnected (normal left inverted right x axis y axis)
It will be great if you can try the patch in
https://bugs.freedesktop.org/show_bug.cgi?id=22761#C8 on the xserver and attach
the output of xorg.0.log.
Created attachment 29224 [details]
This Bugzilla is dropping attachments! I had attached this logfile right away when I opened the bugreport.
(In reply to comment #3)
> Created an attachment (id=29224) [details]
> This Bugzilla is dropping attachments! I had attached this logfile right away
> when I opened the bugreport.
andreas, is the log with patch yakui mentioned in comment# 2 applied?
@Michael: Yes - is there anything that makes you think otherwise?
thanks for the test.
From the test log it seems that the mode 1024x768 is marked as invalid by the xserver as the hsync frequency is beyond the hsync/vsync range, which is calculated by the mode returned by the linux kernel.
When the UMS mode is used, the mode 1280x800 obtained from EDID is invalid. But it is still used to calculate the hsync/vsync range. In such case the mode 1024x768@60Hz won't be removed.
In the KMS mode the mode 1280x800@60HZ is already deleted from the kernel mode list. In such case we will get the hsync/vsync range different with that in UMS mode. In fact this flowchart in KMS mode is more reasonable.
IMO this bug is not our driver bug.
(In reply to comment #6)
> IMO this bug is not our driver bug.
This is a bit frustrating to me, as 1024 x 768 is an important mode on a 1280 x 768 display. Can you point me to where I have to report this bug? I thought the kernel parts of the driver are also hosted here?
(In reply to comment #7)
> (In reply to comment #6)
> > IMO this bug is not our driver bug.
> This is a bit frustrating to me, as 1024 x 768 is an important mode on a 1280 x
> 768 display. Can you point me to where I have to report this bug? I thought the
> kernel parts of the driver are also hosted here?
On this box there exists the EDID for LVDS display device. In such case the mode of 1280x768@60 is returned by kernel driver in KMS mode.
If you think that the mode 1024x768 is important on 1280x800, you can add it manually. Of course you can add the hsync/vsync refresh range in xorg.conf to workaround this issue.
If you think that the 1024x768 should be added automatically, you can report this bug to xserver.
Moving this bug to xserver.
@ykzhao: Note that the display in question is a 1280 x 768 display, _not_ a 1280 x 800.
As 1024 x 768 is the native 4:3 mode on that display, I consider it very important and I feel it should not be needed to configure such an important mode manually.
I think this mode might be present now by default, but either way it sounds like a core DRM or server bug.
Should be fixed in newer intel driver.