Instead of setting vrr.guardband to vblank, use optimal guardband that works for most of the cases. This will help in avoiding need of change in guardband and fix the LRR feature that needs seamless switching to a lower refresh rate.
First few patches fix/refactor and extract common functions required for dsc/scaler prefill time computation. Later patches use these helpers to compute an optimized guardband. Also, for seamless_mn where vtotal is same but mode clock is changed to seamlessly switch to lower rate, re-compute the vrr timings. Few things that still need work: -The timestamps corresponding with next start of vactive still need to be fixed with the new scheme. -Re-enabling CMRR Rev2: -Address comments from Mitul. -Extract helpers for dsc/scaler prefill latencies. -Fix downscaling factor for chroma subsampling. -Use missing pkg C max latency. -Fix guardband computation for seamless mn, always use vblank for higher resolution. Rev3: -Drop patches for computing and storing PSR/Panel Replay wake times latencies and use existing helpers to compute these in intel_alpm.c. -Drop patch to change the Vmin as it was not required. Rev4: -Rebase -Drop patch for checking bounds for scaler array access. -Use a new flag for setting vrr timings for seamless drrs. Rev5: -Address comments from Mitul, Jani: -Refactor few helpers for computing latencies. -Rename the helper to check the guardband to intel_crtc_guardband_atomic_check() -Refactor the helper intel_panel_highest_mode(). Rev6: -Rebase -Address review comments from Mitul. -Improve documentation for and other minor fixes in Patch#12 Rev7: -Address comments from Jani. -Move the latency helpers from intel_display.c to intel_vrr.c and rename the helpers appropriately. -Drop redundant check for HAS_VRR with intel_vrr_possible(). Rev8: -Fix CI issues. -For fixed RR wait for delayed vblank before dsb interrupt. Rev9: -Fix vrr.vsync_start/end timings for 3D modes (patch#1) -Rewrite the patch to wait for delayed vblank before dsb interrupt (patch #11) -Fix the flipline and vmin timings with optimized guardband (patch#12) Rev10: -Address comments from Ville: Use min guardband computation for setting the vblank delay and set the crtc_vblank_start to delayed vblank. (Patch#13) -Modify the TRANS_SET_CONTEXT_LATENCY as per new guardband and use vrr.guardband to readback vblank_start. (Patch#11) -From previous revision: ->Drop patch#11 "drm/i915/dsb: Align flipdone with delayed vblank using guardband wait", as this is no longer required. ->Modify Patch#12 "drm/i915/vrr: Use static guardband to support seamless LRR switching" to only introduce a helper to compute the fix guardband. Modify the commit message and the subject. Ankit Nautiyal (15): drm/i915/vrr: Use crtc_vsync_start/end for computing vrr.vsync_start/end drm/i915/skl_watermark: Fix the scaling factor for chroma subsampling drm/i915/skl_watermark: Pass linetime as argument to latency helpers drm/i915/skl_scaler: Introduce helper for chroma downscale factor drm/i915/display: Extract helpers to set dsc/scaler prefill latencies drm/i915/dp: Add SDP latency computation helper drm/i915/alpm: Add function to compute max link-wake latency drm/i915/vrr: Use vrr.sync_start for getting vtotal drm/i915/display: Add guardband check for feature latencies drm/i915/skl_watermark: Remove redundant latency checks from vblank validation drm/i915/display: Use vrr.guardband to derive vblank_start drm/i915/vrr: Introduce helper to compute min static guardband drm/i915/display: Use optimized guardband to set vblank start drm/i915/panel: Refactor helper to get highest fixed mode drm/i915/vrr: Fix seamless_mn drrs for PTL drivers/gpu/drm/i915/display/intel_alpm.c | 15 + drivers/gpu/drm/i915/display/intel_alpm.h | 2 + drivers/gpu/drm/i915/display/intel_display.c | 236 ++++++++++++++- .../drm/i915/display/intel_display_types.h | 2 + drivers/gpu/drm/i915/display/intel_dp.c | 63 +++- drivers/gpu/drm/i915/display/intel_dp.h | 3 + drivers/gpu/drm/i915/display/intel_panel.c | 11 +- drivers/gpu/drm/i915/display/intel_panel.h | 3 +- drivers/gpu/drm/i915/display/intel_vrr.c | 272 ++++++++++++++++-- drivers/gpu/drm/i915/display/intel_vrr.h | 10 + drivers/gpu/drm/i915/display/skl_scaler.c | 5 + drivers/gpu/drm/i915/display/skl_scaler.h | 3 + drivers/gpu/drm/i915/display/skl_watermark.c | 89 +----- drivers/gpu/drm/i915/display/skl_watermark.h | 1 + 14 files changed, 586 insertions(+), 129 deletions(-) -- 2.45.2