drm/amd/display: Fix idle optimization checks for multi-display and dual eDP

[Why]
Idle optimizations are blocked if there's more than one eDP connector
on the board - blocking S0i3 and IPS2 for static screen.

[How]
Fix the checks to correctly detect number of active eDP.
Also restrict the eDP support to panels that have correct feature
support.

Cc: Mario Limonciello <mario.limonciello@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@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/hwss/dcn35/dcn35_hwseq.c

@@ -660,22 +660,43 @@ void dcn35_power_down_on_boot(struct dc *dc)
 
 bool dcn35_apply_idle_power_optimizations(struct dc *dc, bool enable)
 {
-	struct dc_link *edp_links[MAX_NUM_EDP];
-	int i, edp_num;
 	if (dc->debug.dmcub_emulation)
 		return true;
 
 	if (enable) {
-		dc_get_edp_links(dc, edp_links, &edp_num);
-		if (edp_num == 0 || edp_num > 1)
-			return false;
+		uint32_t num_active_edp = 0;
+		int i;
 
 		for (i = 0; i < dc->current_state->stream_count; ++i) {
 			struct dc_stream_state *stream = dc->current_state->streams[i];
+			struct dc_link *link = stream->link;
+			bool is_psr = link && !link->panel_config.psr.disable_psr &&
+				      (link->psr_settings.psr_version == DC_PSR_VERSION_1 ||
+				       link->psr_settings.psr_version == DC_PSR_VERSION_SU_1);
+			bool is_replay = link && link->replay_settings.replay_feature_enabled;
+
+			/* Ignore streams that disabled. */
+			if (stream->dpms_off)
+				continue;
+
+			/* Active external displays block idle optimizations. */
+			if (!dc_is_embedded_signal(stream->signal))
+				return false;
+
+			/* If not PWRSEQ0 can't enter idle optimizations */
+			if (link && link->link_index != 0)
+				return false;
 
-			if (!stream->dpms_off && !dc_is_embedded_signal(stream->signal))
+			/* Check for panel power features required for idle optimizations. */
+			if (!is_psr && !is_replay)
 				return false;
+
+			num_active_edp += 1;
 		}
+
+		/* If more than one active eDP then disallow. */
+		if (num_active_edp > 1)
+			return false;
 	}
 
 	// TODO: review other cases when idle optimization is allowed