Phoronix: Intel, Radeon DRM Get Precise VBlank Timestamps
Mario Kleiner has published patches over the weekend that introduce precise vblank time-stamping support within the Linux kernel's DRM core and has implemented this support already within the Radeon and Intel kernel drivers too. The precise vblank timestamps and counting is needed by the DRI2 sync and swap extensions and in particular to conform with the OML_sync_control extension...
Have you tried dynpm with the latest kernel code ? IIRC there was a typo fix a couple of weeks ago related to dynpm display flicker.
I am on 2.6.36 final. I bet you are talking about drm-testing, right?
Anyway, last time I tried dynpm it didn't change my clocks at all, i.e. it stayed maxed out. However, I don't feel any performance regression after setting the low profile, so compiz effects are still fast enough for me (obviously fps in games drops). Rv730 if it matters.
Although perhaps someone could clarify this for me: does anything else still need to be implemented in gstreamer/mplayer/etc to properly sync, or is that all in place and ready and it was just lower level DRM issues that were breaking sync?