From: Ville Syrjälä Date: Fri, 7 Feb 2025 22:31:54 +0000 (+0200) Subject: drm/i915/vrr: Account for TRANS_PUSH delay X-Git-Tag: v6.15-rc1~120^2~16^2~79 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=51385d68990cca5263ab9575edd5386f6e42a994;p=thirdparty%2Fkernel%2Flinux.git drm/i915/vrr: Account for TRANS_PUSH delay When we send a push during vblank the TRANS_PUSH write happens at some point during a scanline, and the hardware picks it up on the next scanline. Thus there is up to one extra scanline of delay between the TRANS_PUSH write and the delayed vblank triggering. Account for that during intel_dsb_wait_vblank_delay() so that we are guaranteed to be past the delayed vblank before we trigger the completion interrupt for the commit. Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20250207223159.14132-4-ville.syrjala@linux.intel.com Reviewed-by: Ankit Nautiyal --- diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c index f8bd6fad0c871..01e3bd385cacc 100644 --- a/drivers/gpu/drm/i915/display/intel_dsb.c +++ b/drivers/gpu/drm/i915/display/intel_dsb.c @@ -116,7 +116,13 @@ static int dsb_vblank_delay(struct intel_atomic_state *state, intel_pre_commit_crtc_state(state, crtc); if (pre_commit_is_vrr_active(state, crtc)) - return intel_vrr_vblank_delay(crtc_state); + /* + * When the push is sent during vblank it will trigger + * on the next scanline, hence we have up to one extra + * scanline until the delayed vblank occurs after + * TRANS_PUSH has been written. + */ + return intel_vrr_vblank_delay(crtc_state) + 1; else return intel_mode_vblank_delay(&crtc_state->hw.adjusted_mode); }