Bug#661943: xserver-xorg-video-radeon: Unable to set native resolution with KMS enabled

[Alex Deucher]

On Fri, Mar 2, 2012 at 3:30 PM, Christopher Dow
<christopher.dow at allstardirectories.com> wrote:
> Package: xserver-xorg-video-radeon
> Version: 1:6.14.3-2
> Severity: important
>
> I am unable to set the the native resolution of my monitors with KMS enabled.  Whenever I try to set the native resolution, the monitor displays the following message message (with <resolution> replaced with the apropriate native resolution:
>
> "The current input timing is not supported by the monitor display. Please change your input timing to <resolution> or any other monitor listed timing as per the monitor specifications."
>
> I have two monitors ('Dell P2210' and a 'Dell P2010H').  I am not able to the native resolution for either of these monitors.  You can find the specifications for these monitors here:
>
> http://support.dell.com/support/edocs/monitors/P2210/en/ug/about.htm#Specifications
> http://support.dell.com/support/edocs/monitors/P2010H/en/ug/about.htm#Specifications
>
> Whenever boot into Debian, I get this same message for a few seconds and then the display goes to a lower resolution.  I also get the same message if I try to switch to any of the virtual terminals.
>
> If I disable KMS, I am able to set the native resolution for both of these monitors (however, then I can't set my desktop to span 2 monitors but that is probably a different issue).
>

[    13.127] (II) RADEON(0): Output DisplayPort-0 connected
[    13.127] (II) RADEON(0): Output DisplayPort-1 connected
[    13.127] (II) RADEON(0): Using fuzzy aspect match for initial modes
[    13.127] (II) RADEON(0): Output DisplayPort-0 using initial mode 1152x864
[    13.127] (II) RADEON(0): Output DisplayPort-1 using initial mode 1152x864

The xserver (not the driver) is picking 1152x864 since it's the
largest common mode supported by both monitors.  You'll have to use
xrandr to choose a different mode (or specify different default modes
in your xorg.conf).  Alternatively, you can start up X with one
monitor attached and then enable the second one manually with xrandr.

Alex