drm/i915: Pre-compute pipe enabled state

Add 'new_enabled' to intel_crtc and precompute it alongside new_encoder
and new_crtc. This will allow making decisions about shared resources
that are affected by the set of active pipes, before we've clobbered
anything for real.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -8774,6 +8774,7 @@ static bool intel_encoder_crtc_ok(struct drm_encoder *encoder,
  */
 static void intel_modeset_update_staged_output_state(struct drm_device *dev)
 {
+	struct intel_crtc *crtc;
 	struct intel_encoder *encoder;
 	struct intel_connector *connector;
 
@@ -8788,6 +8789,11 @@ static void intel_modeset_update_staged_output_state(struct drm_device *dev)
 		encoder->new_crtc =
 			to_intel_crtc(encoder->base.crtc);
 	}
+
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list,
+			    base.head) {
+		crtc->new_enabled = crtc->base.enabled;
+	}
 }
 
 /**
@@ -8797,6 +8803,7 @@ static void intel_modeset_update_staged_output_state(struct drm_device *dev)
  */
 static void intel_modeset_commit_output_state(struct drm_device *dev)
 {
+	struct intel_crtc *crtc;
 	struct intel_encoder *encoder;
 	struct intel_connector *connector;
 
@@ -8809,6 +8816,11 @@ static void intel_modeset_commit_output_state(struct drm_device *dev)
 			    base.head) {
 		encoder->base.crtc = &encoder->new_crtc->base;
 	}
+
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list,
+			    base.head) {
+		crtc->base.enabled = crtc->new_enabled;
+	}
 }
 
 static void
@@ -9135,29 +9147,22 @@ intel_modeset_affected_pipes(struct drm_crtc *crtc, unsigned *modeset_pipes,
 			*prepare_pipes |= 1 << encoder->new_crtc->pipe;
 	}
 
-	/* Check for any pipes that will be fully disabled ... */
+	/* Check for pipes that will be enabled/disabled ... */
 	list_for_each_entry(intel_crtc, &dev->mode_config.crtc_list,
 			    base.head) {
-		bool used = false;
-
-		/* Don't try to disable disabled crtcs. */
-		if (!intel_crtc->base.enabled)
+		if (intel_crtc->base.enabled == intel_crtc->new_enabled)
 			continue;
 
-		list_for_each_entry(encoder, &dev->mode_config.encoder_list,
-				    base.head) {
-			if (encoder->new_crtc == intel_crtc)
-				used = true;
-		}
-
-		if (!used)
+		if (!intel_crtc->new_enabled)
 			*disable_pipes |= 1 << intel_crtc->pipe;
+		else
+			*prepare_pipes |= 1 << intel_crtc->pipe;
 	}
 
 
 	/* set_mode is also used to update properties on life display pipes. */
 	intel_crtc = to_intel_crtc(crtc);
-	if (crtc->enabled)
+	if (intel_crtc->new_enabled)
 		*prepare_pipes |= 1 << intel_crtc->pipe;
 
 	/*
@@ -9216,10 +9221,10 @@ intel_modeset_update_state(struct drm_device *dev, unsigned prepare_pipes)
 
 	intel_modeset_commit_output_state(dev);
 
-	/* Update computed state. */
+	/* Double check state. */
 	list_for_each_entry(intel_crtc, &dev->mode_config.crtc_list,
 			    base.head) {
-		intel_crtc->base.enabled = intel_crtc_in_use(&intel_crtc->base);
+		WARN_ON(intel_crtc->base.enabled != intel_crtc_in_use(&intel_crtc->base));
 	}
 
 	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
@@ -9754,16 +9759,24 @@ static void intel_set_config_free(struct intel_set_config *config)
 
 	kfree(config->save_connector_encoders);
 	kfree(config->save_encoder_crtcs);
+	kfree(config->save_crtc_enabled);
 	kfree(config);
 }
 
 static int intel_set_config_save_state(struct drm_device *dev,
 				       struct intel_set_config *config)
 {
+	struct drm_crtc *crtc;
 	struct drm_encoder *encoder;
 	struct drm_connector *connector;
 	int count;
 
+	config->save_crtc_enabled =
+		kcalloc(dev->mode_config.num_crtc,
+			sizeof(bool), GFP_KERNEL);
+	if (!config->save_crtc_enabled)
+		return -ENOMEM;
+
 	config->save_encoder_crtcs =
 		kcalloc(dev->mode_config.num_encoder,
 			sizeof(struct drm_crtc *), GFP_KERNEL);
@@ -9780,6 +9793,11 @@ static int intel_set_config_save_state(struct drm_device *dev,
 	 * Should anything bad happen only the expected state is
 	 * restored, not the drivers personal bookkeeping.
 	 */
+	count = 0;
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+		config->save_crtc_enabled[count++] = crtc->enabled;
+	}
+
 	count = 0;
 	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 		config->save_encoder_crtcs[count++] = encoder->crtc;
@@ -9796,10 +9814,16 @@ static int intel_set_config_save_state(struct drm_device *dev,
 static void intel_set_config_restore_state(struct drm_device *dev,
 					   struct intel_set_config *config)
 {
+	struct intel_crtc *crtc;
 	struct intel_encoder *encoder;
 	struct intel_connector *connector;
 	int count;
 
+	count = 0;
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list, base.head) {
+		crtc->new_enabled = config->save_crtc_enabled[count++];
+	}
+
 	count = 0;
 	list_for_each_entry(encoder, &dev->mode_config.encoder_list, base.head) {
 		encoder->new_crtc =
@@ -9884,9 +9908,9 @@ intel_modeset_stage_output_state(struct drm_device *dev,
 				 struct drm_mode_set *set,
 				 struct intel_set_config *config)
 {
-	struct drm_crtc *new_crtc;
 	struct intel_connector *connector;
 	struct intel_encoder *encoder;
+	struct intel_crtc *crtc;
 	int ro;
 
 	/* The upper layers ensure that we either disable a crtc or have a list
@@ -9929,6 +9953,8 @@ intel_modeset_stage_output_state(struct drm_device *dev,
 	/* Update crtc of enabled connectors. */
 	list_for_each_entry(connector, &dev->mode_config.connector_list,
 			    base.head) {
+		struct drm_crtc *new_crtc;
+
 		if (!connector->new_encoder)
 			continue;
 
@@ -9979,6 +10005,26 @@ intel_modeset_stage_output_state(struct drm_device *dev,
 	}
 	/* Now we've also updated encoder->new_crtc for all encoders. */
 
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list,
+			    base.head) {
+		crtc->new_enabled = false;
+
+		list_for_each_entry(encoder,
+				    &dev->mode_config.encoder_list,
+				    base.head) {
+			if (encoder->new_crtc == crtc) {
+				crtc->new_enabled = true;
+				break;
+			}
+		}
+
+		if (crtc->new_enabled != crtc->base.enabled) {
+			DRM_DEBUG_KMS("crtc %sabled, full mode switch\n",
+				      crtc->new_enabled ? "en" : "dis");
+			config->mode_changed = true;
+		}
+	}
+
 	return 0;
 }
 

drivers/gpu/drm/i915/intel_drv.h

@@ -359,6 +359,7 @@ struct intel_crtc {
 	bool cursor_visible;
 
 	struct intel_crtc_config config;
+	bool new_enabled;
 
 	uint32_t ddi_pll_sel;
 
@@ -540,6 +541,7 @@ struct intel_unpin_work {
 struct intel_set_config {
 	struct drm_encoder **save_connector_encoders;
 	struct drm_crtc **save_encoder_crtcs;
+	bool *save_crtc_enabled;
 
 	bool fb_changed;
 	bool mode_changed;