kms causes broken vsync with r600.

[Alex Deucher]

2010/4/16  <rdxijn at yandex.ru>:
>
>
> 16.04.10, 10:58, "Alex Deucher" <alexdeucher at gmail.com>:
>
>> On Fri, Apr 16, 2010 at 10:16 AM,   wrote:
>>  >
>>  > Enabling kms with r600 causes serious problems with vsync. For example, glxgears with low-res window works just as there is no vsync, and with large window fps becomes 60, but visible and regular lags appear - rendering just stop approximately once a second for a sort moment.  EXAVSync options seems has no effect. Also there is following error when starting gl apps:
>>  >
>>  > do_wait: drmWaitVBlank returned -1, IRQs don't seem to be working correctly.
>>  > Try adjusting the vblank_mode configuration parameter.
>>  >
>>  > Adjusting vblank_mode var doesn't work ether. With ums there is no sync problem.
>>  >
>>
>>  those options are not supported under kms at the moment.
>>
>>  > I'm using Debian Squeeze with mesa 7.7.1-1 and radeon 6.13.0-1. Also i have two 1920x1080 panels connected via dvi.
>>
>>  What kernel are you using?  You need 2.6.33 for r6xx+ irq support
>>  which is required for vblank irqs.
>>
>>  Alex
>>
>>
>
> I've installed 2.6.33, there is indeed no drmWaitVBlank error, but the problem still exists.
>

The dri_config vblank options don't work with kms.  you need to use
one of the GLX vsync extensions.

Alex