drm/i915/gen11: Link nv12 Y and UV planes in the atomic state, v5.

To make NV12 working on icl, we need to update 2 planes simultaneously.
I've chosen to do this in the CRTC step after plane validation is done,
so we know what planes are (in)visible. The linked Y plane will get
updated in intel_plane_update_planes_on_crtc(), by the call to
update_slave, which gets the master's plane_state as argument.

The link requires both planes for atomic_update to work,
so make sure skl_ddb_add_affected_planes() adds both states.

Changes since v1:
- Introduce icl_is_nv12_y_plane(), instead of hardcoding sprite numbers.
- Put all the state updating login in intel_plane_atomic_check_with_state().
- Clean up changes in intel_plane_atomic_check().
Changes since v2:
- Fix intel_atomic_get_old_plane_state() to actually return old state.
- Move visibility changes to preparation patch.
- Only try to find a Y plane on gen11, earlier platforms only require
  a single plane.
Changes since v3:
- Fix checkpatch warning about to_intel_crtc() usage.
- Add affected planes from icl_add_linked_planes() before check_planes(),
  it's a cleaner way to do this. (Ville)
Changes since v4:
- Clear plane links in icl_check_nv12_planes() for clarity.
- Only pass crtc_state to icl_check_nv12_planes().
- Use for_each_new_intel_plane_in_state() in icl_check_nv12_planes.
- Rename aux to linked. (Ville)

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181022135152.15324-1-maarten.lankhorst@linux.intel.com
[mlankhorst: Change bool slave to u32, to satisfy checkpatch]
[mlankhorst: Add WARN_ON's based on Ville's suggestion]

drivers/gpu/drm/i915/intel_atomic_plane.c

@@ -188,6 +188,25 @@ void intel_update_planes_on_crtc(struct intel_atomic_state *old_state,
 			trace_intel_update_plane(&plane->base, crtc);
 
 			plane->update_plane(plane, new_crtc_state, new_plane_state);
+		} else if (new_plane_state->slave) {
+			struct intel_plane *master =
+				new_plane_state->linked_plane;
+
+			/*
+			 * We update the slave plane from this function because
+			 * programming it from the master plane's update_plane
+			 * callback runs into issues when the Y plane is
+			 * reassigned, disabled or used by a different plane.
+			 *
+			 * The slave plane is updated with the master plane's
+			 * plane_state.
+			 */
+			new_plane_state =
+				intel_atomic_get_new_plane_state(old_state, master);
+
+			trace_intel_update_plane(&plane->base, crtc);
+
+			plane->update_slave(plane, new_crtc_state, new_plane_state);
 		} else {
 			trace_intel_disable_plane(&plane->base, crtc);
 

drivers/gpu/drm/i915/intel_display.c

@@ -10713,6 +10713,98 @@ static bool check_single_encoder_cloning(struct drm_atomic_state *state,
 	return true;
 }
 
+static int icl_add_linked_planes(struct intel_atomic_state *state)
+{
+	struct intel_plane *plane, *linked;
+	struct intel_plane_state *plane_state, *linked_plane_state;
+	int i;
+
+	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
+		linked = plane_state->linked_plane;
+
+		if (!linked)
+			continue;
+
+		linked_plane_state = intel_atomic_get_plane_state(state, linked);
+		if (IS_ERR(linked_plane_state))
+			return PTR_ERR(linked_plane_state);
+
+		WARN_ON(linked_plane_state->linked_plane != plane);
+		WARN_ON(linked_plane_state->slave == plane_state->slave);
+	}
+
+	return 0;
+}
+
+static int icl_check_nv12_planes(struct intel_crtc_state *crtc_state)
+{
+	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	struct intel_atomic_state *state = to_intel_atomic_state(crtc_state->base.state);
+	struct intel_plane *plane, *linked;
+	struct intel_plane_state *plane_state;
+	int i;
+
+	if (INTEL_GEN(dev_priv) < 11)
+		return 0;
+
+	/*
+	 * Destroy all old plane links and make the slave plane invisible
+	 * in the crtc_state->active_planes mask.
+	 */
+	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
+		if (plane->pipe != crtc->pipe || !plane_state->linked_plane)
+			continue;
+
+		plane_state->linked_plane = NULL;
+		if (plane_state->slave && !plane_state->base.visible)
+			crtc_state->active_planes &= ~BIT(plane->id);
+
+		plane_state->slave = false;
+	}
+
+	if (!crtc_state->nv12_planes)
+		return 0;
+
+	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
+		struct intel_plane_state *linked_state = NULL;
+
+		if (plane->pipe != crtc->pipe ||
+		    !(crtc_state->nv12_planes & BIT(plane->id)))
+			continue;
+
+		for_each_intel_plane_on_crtc(&dev_priv->drm, crtc, linked) {
+			if (!icl_is_nv12_y_plane(linked->id))
+				continue;
+
+			if (crtc_state->active_planes & BIT(linked->id))
+				continue;
+
+			linked_state = intel_atomic_get_plane_state(state, linked);
+			if (IS_ERR(linked_state))
+				return PTR_ERR(linked_state);
+
+			break;
+		}
+
+		if (!linked_state) {
+			DRM_DEBUG_KMS("Need %d free Y planes for NV12\n",
+				      hweight8(crtc_state->nv12_planes));
+
+			return -EINVAL;
+		}
+
+		plane_state->linked_plane = linked;
+
+		linked_state->slave = true;
+		linked_state->linked_plane = plane;
+		crtc_state->active_planes |= BIT(linked->id);
+		DRM_DEBUG_KMS("Using %s as Y plane for %s\n", linked->base.name, plane->base.name);
+	}
+
+	return 0;
+}
+
 static int intel_crtc_atomic_check(struct drm_crtc *crtc,
 				   struct drm_crtc_state *crtc_state)
 {
@@ -10784,6 +10876,8 @@ static int intel_crtc_atomic_check(struct drm_crtc *crtc,
 		if (mode_changed)
 			ret = skl_update_scaler_crtc(pipe_config);
 
+		if (!ret)
+			ret = icl_check_nv12_planes(pipe_config);
 		if (!ret)
 			ret = skl_check_pipe_max_pixel_rate(intel_crtc,
 							    pipe_config);
@@ -12450,6 +12544,10 @@ static int intel_atomic_check(struct drm_device *dev,
 		intel_state->cdclk.logical = dev_priv->cdclk.logical;
 	}
 
+	ret = icl_add_linked_planes(intel_state);
+	if (ret)
+		return ret;
+
 	ret = drm_atomic_helper_check_planes(dev, state);
 	if (ret)
 		return ret;

drivers/gpu/drm/i915/intel_drv.h

@@ -539,6 +539,26 @@ struct intel_plane_state {
 	 */
 	int scaler_id;
 
+	/*
+	 * linked_plane:
+	 *
+	 * ICL planar formats require 2 planes that are updated as pairs.
+	 * This member is used to make sure the other plane is also updated
+	 * when required, and for update_slave() to find the correct
+	 * plane_state to pass as argument.
+	 */
+	struct intel_plane *linked_plane;
+
+	/*
+	 * slave:
+	 * If set don't update use the linked plane's state for updating
+	 * this plane during atomic commit with the update_slave() callback.
+	 *
+	 * It's also used by the watermark code to ignore wm calculations on
+	 * this plane. They're calculated by the linked plane's wm code.
+	 */
+	u32 slave;
+
 	struct drm_intel_sprite_colorkey ckey;
 };
 
@@ -983,6 +1003,9 @@ struct intel_plane {
 	void (*update_plane)(struct intel_plane *plane,
 			     const struct intel_crtc_state *crtc_state,
 			     const struct intel_plane_state *plane_state);
+	void (*update_slave)(struct intel_plane *plane,
+			     const struct intel_crtc_state *crtc_state,
+			     const struct intel_plane_state *plane_state);
 	void (*disable_plane)(struct intel_plane *plane,
 			      struct intel_crtc *crtc);
 	bool (*get_hw_state)(struct intel_plane *plane, enum pipe *pipe);
@@ -1357,6 +1380,27 @@ hdmi_to_dig_port(struct intel_hdmi *intel_hdmi)
 	return container_of(intel_hdmi, struct intel_digital_port, hdmi);
 }
 
+static inline struct intel_plane_state *
+intel_atomic_get_plane_state(struct intel_atomic_state *state,
+				 struct intel_plane *plane)
+{
+	struct drm_plane_state *ret =
+		drm_atomic_get_plane_state(&state->base, &plane->base);
+
+	if (IS_ERR(ret))
+		return ERR_CAST(ret);
+
+	return to_intel_plane_state(ret);
+}
+
+static inline struct intel_plane_state *
+intel_atomic_get_old_plane_state(struct intel_atomic_state *state,
+				 struct intel_plane *plane)
+{
+	return to_intel_plane_state(drm_atomic_get_old_plane_state(&state->base,
+								   &plane->base));
+}
+
 static inline struct intel_plane_state *
 intel_atomic_get_new_plane_state(struct intel_atomic_state *state,
 				 struct intel_plane *plane)
@@ -2165,6 +2209,15 @@ struct intel_plane *
 skl_universal_plane_create(struct drm_i915_private *dev_priv,
 			   enum pipe pipe, enum plane_id plane_id);
 
+static inline bool icl_is_nv12_y_plane(enum plane_id id)
+{
+	/* Don't need to do a gen check, these planes are only available on gen11 */
+	if (id == PLANE_SPRITE4 || id == PLANE_SPRITE5)
+		return true;
+
+	return false;
+}
+
 /* intel_tv.c */
 void intel_tv_init(struct drm_i915_private *dev_priv);
 

drivers/gpu/drm/i915/intel_pm.c

@@ -5153,11 +5153,12 @@ skl_ddb_add_affected_planes(struct intel_crtc_state *cstate)
 	struct intel_atomic_state *intel_state = to_intel_atomic_state(state);
 	struct skl_ddb_allocation *new_ddb = &intel_state->wm_results.ddb;
 	struct skl_ddb_allocation *cur_ddb = &dev_priv->wm.skl_hw.ddb;
-	struct drm_plane_state *plane_state;
 	struct drm_plane *plane;
 	enum pipe pipe = intel_crtc->pipe;
 
 	drm_for_each_plane_mask(plane, dev, cstate->base.plane_mask) {
+		struct drm_plane_state *plane_state;
+		struct intel_plane *linked;
 		enum plane_id plane_id = to_intel_plane(plane)->id;
 
 		if (skl_ddb_entry_equal(&cur_ddb->plane[pipe][plane_id],
@@ -5169,6 +5170,15 @@ skl_ddb_add_affected_planes(struct intel_crtc_state *cstate)
 		plane_state = drm_atomic_get_plane_state(state, plane);
 		if (IS_ERR(plane_state))
 			return PTR_ERR(plane_state);
+
+		/* Make sure linked plane is updated too */
+		linked = to_intel_plane_state(plane_state)->linked_plane;
+		if (!linked)
+			continue;
+
+		plane_state = drm_atomic_get_plane_state(state, &linked->base);
+		if (IS_ERR(plane_state))
+			return PTR_ERR(plane_state);
 	}
 
 	return 0;