Without async flip support in the kernel, fullscreen apps where game resolution is equal to the screen resolution, must perform an extra blit per frame prior to flipping.
Asynchronous page flips will also boost the FPS of Mesa benchmarks.
v2: -Few patches have been squashed and patches have been shuffled as per the reviews on the previous version.
v3: -Few patches have been squashed and patches have been shuffled as per the reviews on the previous version.
v4: -Made changes to fix the sequence and time stamp issue as per the comments received on the previous version. -Timestamps are calculated using the flip done time stamp and current timestamp. Here I915_MODE_FLAG_GET_SCANLINE_FROM_TIMESTAMP flag is used for timestamp calculations. -Event is sent from the interrupt handler immediately using this updated timestamps and sequence. -Added more state checks as async flip should only allow change in plane surface address and nothing else should be allowed to change. -Added a separate plane hook for async flip. -Need to find a way to reject fbc enabling if it comes as part of this flip as bspec states that changes to FBC are not allowed.
v5: -Fixed the Checkpatch and sparse warnings.
v6: -Reverted back to the old timestamping code as per the feedback received. -Added documentation.
Test-with: 20200806132935.23293-1-karthik.b.s@intel.com
Karthik B S (7): drm/i915: Add enable/disable flip done and flip done handler drm/i915: Add support for async flips in I915 drm/i915: Add checks specific to async flips drm/i915: Do not call drm_crtc_arm_vblank_event in async flips drm/i915: Add dedicated plane hook for async flip case Documentation/gpu: Add asynchronous flip documentation for i915 drm/i915: Enable async flips in i915
Documentation/gpu/i915.rst | 6 + drivers/gpu/drm/i915/display/intel_display.c | 127 +++++++++++++++++++ drivers/gpu/drm/i915/display/intel_sprite.c | 33 ++++- drivers/gpu/drm/i915/i915_irq.c | 52 ++++++++ drivers/gpu/drm/i915/i915_irq.h | 2 + drivers/gpu/drm/i915/i915_reg.h | 1 + 6 files changed, 220 insertions(+), 1 deletion(-)