forked from Minki/linux
49b14a5ca2
This patch changes the strategy for pageflip completion timestamping. It detects if the pageflip completion routine gets executed before or after drm_handle_vblank, and thereby decides if the returned vblank count and timestamp must be incremented by 1 frame(duration) or not. It compares the current system time at invocation against the current vblank timestamp. If the difference is more than 0.9 video refresh interval durations then it assumes the vblank timestamp and count are outdated and need to be incremented and does so. Otherwise it assumes a delayed pageflip irq and doesn't correct the timestamp and count. Advantage of this patch: Pageflip timestamping becomes more robust against implementation errors and is maintenance free for future GPU's. Disadvantage: A few dozen (hundred?) nsecs extra time spent in pageflip irq handler for each flip, compared to hard-coded per-gpu settings? Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de> Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> |
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| drm | ||
| stub | ||
| vga | ||
| Makefile | ||