drm/amd/display: apply vmin optimization even if it doesn't reach vmin level

[why]
Based on power measurement result, in most cases when display clock
is higher than Vmin display clock, lowering display clock using
dynamic ODM will improve overall power consumption by 0 to 4 watts
even if we can't reach Vmin.

[how]
Allow vmin optimization applied even if dispclk can't reach Vmin.
Reviewed-by: Austin Zheng <austin.zheng@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_pmo/dml2_pmo_dcn4_fams2.c

@@ -717,6 +717,8 @@ bool pmo_dcn4_fams2_init_for_vmin(struct dml2_pmo_init_for_vmin_in_out *in_out)
 			&in_out->base_display_config->display_config;
 	const struct dml2_core_mode_support_result *mode_support_result =
 			&in_out->base_display_config->mode_support_result;
+	struct dml2_optimization_stage4_state *state =
+			&in_out->base_display_config->stage4;
 
 	if (in_out->instance->options->disable_dyn_odm ||
 			(in_out->instance->options->disable_dyn_odm_for_multi_stream && display_config->num_streams > 1))
@@ -737,28 +739,30 @@ bool pmo_dcn4_fams2_init_for_vmin(struct dml2_pmo_init_for_vmin_in_out *in_out)
 		 */
 		if (mode_support_result->cfg_support_info.plane_support_info[i].dpps_used > 1 &&
 				mode_support_result->cfg_support_info.stream_support_info[display_config->plane_descriptors[i].stream_index].odms_used == 1)
-			in_out->base_display_config->stage4.unoptimizable_streams[display_config->plane_descriptors[i].stream_index] = true;
+			state->unoptimizable_streams[display_config->plane_descriptors[i].stream_index] = true;
 
 	for (i = 0; i < display_config->num_streams; i++) {
 		if (display_config->stream_descriptors[i].overrides.disable_dynamic_odm)
-			in_out->base_display_config->stage4.unoptimizable_streams[i] = true;
+			state->unoptimizable_streams[i] = true;
 		else if (in_out->base_display_config->stage3.stream_svp_meta[i].valid &&
 				in_out->instance->options->disable_dyn_odm_for_stream_with_svp)
-			in_out->base_display_config->stage4.unoptimizable_streams[i] = true;
+			state->unoptimizable_streams[i] = true;
 		/*
 		 * ODM Combine requires horizontal timing divisible by 2 so each
 		 * ODM segment has the same size.
 		 */
 		else if (!is_h_timing_divisible_by(&display_config->stream_descriptors[i].timing, 2))
-			in_out->base_display_config->stage4.unoptimizable_streams[i] = true;
+			state->unoptimizable_streams[i] = true;
 		/*
 		 * Our hardware support seamless ODM transitions for DP encoders
 		 * only.
 		 */
 		else if (!is_dp_encoder(display_config->stream_descriptors[i].output.output_encoder))
-			in_out->base_display_config->stage4.unoptimizable_streams[i] = true;
+			state->unoptimizable_streams[i] = true;
 	}
 
+	state->performed = true;
+
 	return true;
 }
 

drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_top/dml_top.c

@@ -266,9 +266,18 @@ bool dml2_build_mode_programming(struct dml2_build_mode_programming_in_out *in_o
 
 	vmin_success = dml2_top_optimization_perform_optimization_phase(&l->optimization_phase_locals, &l->vmin_phase);
 
-	if (vmin_success) {
+	if (l->optimized_display_config_with_meta.stage4.performed) {
+		/*
+		 * when performed is true, optimization has applied to
+		 * optimized_display_config_with_meta and it has passed mode
+		 * support. However it may or may not pass the test function to
+		 * reach actual Vmin. As long as voltage is optimized even if it
+		 * doesn't reach Vmin level, there is still power benefit so in
+		 * this case we will still copy this optimization into base
+		 * display config.
+		 */
 		memcpy(&l->base_display_config_with_meta, &l->optimized_display_config_with_meta, sizeof(struct display_configuation_with_meta));
-		l->base_display_config_with_meta.stage4.success = true;
+		l->base_display_config_with_meta.stage4.success = vmin_success;
 	}
 
 	/*