drm/amd/display: Don't adjust VRR unnecessarily

[why]
Do not need to spend time reprogramming DRR if there were no updates to
the parameters.

[how]
Compare the current stream state to the requested one to determine if an
update is required.

In amdgpu_dm the timing_changed flag is set but never used so can remove it.
Similarly, the stream update for VRR is done after dc_commit and should
not update its adjust field until after the update is completed.  The
adjust field is managed by dc_stream_adjust_vmin_vmax and should not be
manually updated in amdgpu_dm.
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Pavle Kotarac <Pavle.Kotarac@amd.com>
Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -7370,11 +7370,6 @@ static void update_freesync_state_on_stream(
 		&vrr_infopacket,
 		pack_sdp_v1_3);
 
-	new_crtc_state->freesync_timing_changed |=
-		(memcmp(&acrtc->dm_irq_params.vrr_params.adjust,
-			&vrr_params.adjust,
-			sizeof(vrr_params.adjust)) != 0);
-
 	new_crtc_state->freesync_vrr_info_changed |=
 		(memcmp(&new_crtc_state->vrr_infopacket,
 			&vrr_infopacket,
@@ -7383,7 +7378,6 @@ static void update_freesync_state_on_stream(
 	acrtc->dm_irq_params.vrr_params = vrr_params;
 	new_crtc_state->vrr_infopacket = vrr_infopacket;
 
-	new_stream->adjust = acrtc->dm_irq_params.vrr_params.adjust;
 	new_stream->vrr_infopacket = vrr_infopacket;
 
 	if (new_crtc_state->freesync_vrr_info_changed)
@@ -7446,10 +7440,6 @@ static void update_stream_irq_parameters(
 				      new_stream,
 				      &config, &vrr_params);
 
-	new_crtc_state->freesync_timing_changed |=
-		(memcmp(&acrtc->dm_irq_params.vrr_params.adjust,
-			&vrr_params.adjust, sizeof(vrr_params.adjust)) != 0);
-
 	new_crtc_state->freesync_config = config;
 	/* Copy state for access from DM IRQ handler */
 	acrtc->dm_irq_params.freesync_config = config;

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h

@@ -681,7 +681,6 @@ struct dm_crtc_state {
 
 	int crc_skip_count;
 
-	bool freesync_timing_changed;
 	bool freesync_vrr_info_changed;
 
 	bool dsc_force_changed;

drivers/gpu/drm/amd/display/dc/core/dc.c

@@ -401,6 +401,9 @@ bool dc_stream_adjust_vmin_vmax(struct dc *dc,
 {
 	int i;
 
+	if (memcmp(adjust, &stream->adjust, sizeof(struct dc_crtc_timing_adjust)) == 0)
+		return true;
+
 	stream->adjust.v_total_max = adjust->v_total_max;
 	stream->adjust.v_total_mid = adjust->v_total_mid;
 	stream->adjust.v_total_mid_frame_num = adjust->v_total_mid_frame_num;