diff options
| -rw-r--r-- | drivers/gpu/drm/radeon/radeon_display.c | 30 |
1 files changed, 22 insertions, 8 deletions
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c index 890171f08987..50706464d456 100644 --- a/drivers/gpu/drm/radeon/radeon_display.c +++ b/drivers/gpu/drm/radeon/radeon_display.c @@ -321,16 +321,30 @@ void radeon_crtc_handle_vblank(struct radeon_device *rdev, int crtc_id) update_pending = radeon_page_flip_pending(rdev, crtc_id); /* Has the pageflip already completed in crtc, or is it certain - * to complete in this vblank? + * to complete in this vblank? GET_DISTANCE_TO_VBLANKSTART provides + * distance to start of "fudged earlier" vblank in vpos, distance to + * start of real vblank in hpos. vpos >= 0 && hpos < 0 means we are in + * the last few scanlines before start of real vblank, where the vblank + * irq can fire, so we have sampled update_pending a bit too early and + * know the flip will complete at leading edge of the upcoming real + * vblank. On pre-AVIVO hardware, flips also complete inside the real + * vblank, not only at leading edge, so if update_pending for hpos >= 0 + * == inside real vblank, the flip will complete almost immediately. + * Note that this method of completion handling is still not 100% race + * free, as we could execute before the radeon_flip_work_func managed + * to run and set the RADEON_FLIP_SUBMITTED status, thereby we no-op, + * but the flip still gets programmed into hw and completed during + * vblank, leading to a delayed emission of the flip completion event. + * This applies at least to pre-AVIVO hardware, where flips are always + * completing inside vblank, not only at leading edge of vblank. */ if (update_pending && - (DRM_SCANOUTPOS_VALID & radeon_get_crtc_scanoutpos(rdev->ddev, - crtc_id, - USE_REAL_VBLANKSTART, - &vpos, &hpos, NULL, NULL, - &rdev->mode_info.crtcs[crtc_id]->base.hwmode)) && - ((vpos >= (99 * rdev->mode_info.crtcs[crtc_id]->base.hwmode.crtc_vdisplay)/100) || - (vpos < 0 && !ASIC_IS_AVIVO(rdev)))) { + (DRM_SCANOUTPOS_VALID & + radeon_get_crtc_scanoutpos(rdev->ddev, crtc_id, + GET_DISTANCE_TO_VBLANKSTART, + &vpos, &hpos, NULL, NULL, + &rdev->mode_info.crtcs[crtc_id]->base.hwmode)) && + ((vpos >= 0 && hpos < 0) || (hpos >= 0 && !ASIC_IS_AVIVO(rdev)))) { /* crtc didn't flip in this target vblank interval, * but flip is pending in crtc. Based on the current * scanout position we know that the current frame is |