When booting with KMS disabled, the ati UMS xorg driver properly sets the display mode to 1400x1050@60.2hz. xrandr reports the following modes: $ DISPLAY=:0 xrandr Screen 0: minimum 320 x 200, current 1400 x 1050, maximum 1400 x 1400 VGA-0 disconnected (normal left inverted right x axis y axis) LVDS connected 1400x1050+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1400x1050 60.2*+ 1280x1024 59.9 60.0 1280x960 60.0 59.9 1280x854 59.9 1280x800 59.8 1280x720 59.9 1152x768 59.8 1024x768 60.0 59.9 800x600 60.3 59.9 640x480 59.9 59.4 S-video disconnected (normal left inverted right x axis y axis) However when booting with KMS enabled, all that appears is a black screen. After verifying that fbcon is built into the kernel and that KMS is initializing, I also found that the xserver had started up, but still with a blank screen. After blindly logging in, I ssh'd into the box, and found the following xrandr modes: $ DISPLAY=:0 xrandr Screen 0: minimum 320 x 200, current 1400 x 1050, maximum 4096 x 4096 VGA-0 disconnected (normal left inverted right x axis y axis) LVDS connected 1400x1050+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1400x1050 60.5 + 60.0* 1280x1024 59.9 60.0 1280x960 60.0 59.9 1280x854 59.9 1280x800 59.8 1280x720 59.9 1152x768 59.8 1024x768 60.0 59.9 800x600 60.3 59.9 848x480 59.7 720x480 59.7 640x480 59.9 59.4 S-video disconnected (normal left inverted right x axis y axis) It appears when using KMS, the correct refresh rate for the 1400x1050 resolution isn't found and instead is a rate that doesn't work with this panel gets setup, resulting in a blank screen.
Created attachment 24680 [details] Dmesg under Ums
Created attachment 24681 [details] Dmesg under kms
Oops first attachment is under ums.
Created attachment 24682 [details] Xorg.0.log under ums
Created attachment 24683 [details] Xorg.0.log under kms
Forgot to add: Switching modes under kms with xrandr to a resolution below 1400x1050 results in a working display, although at a poorer resolution. Switching back to the 1400x1050 mode results in a black screen again.
Under KMS you have two 1400x1050 modes: LVDS connected 1400x1050+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1400x1050 60.5 + 60.0* For some reason, 1400x1050@60 is being selected (marked with the *) while 1400x1050@60.5 is the panel's preferred mode (marked with the +). Does selecting 1400x1050@60.5 with xrandr work? e.g., xrandr --output LVDS --mode 1400x1050 --rate 60.5
Okay, after boot it does default to the 60.5 rate, but only displaying the black screen: $DISPLAY=:0 xrandr Screen 0: minimum 320 x 200, current 1400 x 1050, maximum 4096 x 4096 VGA-0 disconnected (normal left inverted right x axis y axis) LVDS connected 1400x1050+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1400x1050 60.5*+ 60.0 1280x1024 59.9 60.0 1280x960 60.0 59.9 1280x854 59.9 1280x800 59.8 1280x720 59.9 1152x768 59.8 1024x768 60.0 59.9 800x600 60.3 59.9 848x480 59.7 720x480 59.7 640x480 59.9 59.4 S-video disconnected (normal left inverted right x axis y axis) After switching to a different resolution or to the 60.0 rate (still a black screen), I can't switch back to the 60.5 rate: $ DISPLAY=:0 xrandr -s 1400x1050 --rate 60.5 $ DISPLAY=:0 xrandr Screen 0: minimum 320 x 200, current 1400 x 1050, maximum 4096 x 4096 VGA-0 disconnected (normal left inverted right x axis y axis) LVDS connected 1400x1050+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1400x1050 60.5 + 60.0* 1280x1024 59.9 60.0 1280x960 60.0 59.9 1280x854 59.9 1280x800 59.8 1280x720 59.9 1152x768 59.8 1024x768 60.0 59.9 800x600 60.3 59.9 848x480 59.7 720x480 59.7 640x480 59.9 59.4 S-video disconnected (normal left inverted right x axis y axis)
Can you attach a copy of your video bios? as root: cd /sys/bus/pci/devices/<pci bus id> echo 1 > rom cat rom > /tmp/rv250.rom echo 0 > rom
Created attachment 24699 [details] RV250 bios Here you go.
This problem is still present in 2.6.33 final.
Still present with 2.6.34-rc+ at about 0fdf86754f70e813845af4abaa805165ce57a0bb.
Finally got around to upgrading that machine to 2.6.38, and KMS now sets a proper mode.