tv-output on radeon 7000M using crtc 0

Songmao Tian tiansm at
Mon Oct 15 22:29:43 PDT 2007

Alex Deucher wrote:
> On 10/15/07, Songmao Tian <tiansm at> wrote:
>> Hello,
>>     radeon vidix driver of Mplayer seems to use crtc 0,  so I want to
>> force tv-out to use crtc 0, I issue the following command but failed.
>> loongson at debian:~/project/x-ati/xrandr/xrandr$ ./xrandr --output S-video
>> --mode 640x480 --crtc 0
>> X Error of failed request:  BadMatch (invalid parameter attributes)
>>   Major opcode of failed request:  155 (RANDR)
>>   Minor opcode of failed request:  21 ()
>>   Serial number of failed request:  17
>>   Current serial number in output stream:  17
>> so how to fix it? I have been tracing the xrandr, but without good result.
> right now the driver will only allow you to enable one output per
> crtc, so you'll need to change whatever is using crtc 0 to use crtc1
> or turn whatever is using crtc 0 off so that you can free up crtc 0
> for use with the tv port.  Depending on your setup, you might also be
> able to use output cloning (assigning multiple outputs to one crtc)
> using the following patch:
> Alex
Thank you! clone mode works for me. but Xv doesn't, and the performance
is not as good as vidix.

And I have try the following script to make tv out get crtc 0 which I
confirmed with xrandr --verbose, but the X crashes and restarts.

loongson at debian:~/project/x-ati$ cat c2
./a  --addmode S-video 640x480
./a --output VGA-0 --off
./a --output S-video --auto
./a --output S-video --mode 640x480


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