drm/i915: Clean up dbuf debugs during .atomic_check()

Combine the two per-pipe dbuf debugs into one, and use the canonical
[CRTC:%d:%s] style to identify the crtc. Also use the same style as
the plane code uses for the ddb start/end, and prefix bitmask properly
with 0x to make it clear they are in fact bitmasks.

The "how many total slices we are going to use" debug we move to
outside the crtc loop so it gets printed only once at the end.

Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200225171125.28885-12-ville.syrjala@linux.intel.comReviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>

drivers/gpu/drm/i915/intel_pm.c

@@ -4105,10 +4105,6 @@ skl_ddb_get_pipe_allocation_limits(struct drm_i915_private *dev_priv,
 	 */
 	dbuf_slice_mask = skl_compute_dbuf_slices(crtc_state, active_pipes);
 
-	DRM_DEBUG_KMS("DBuf slice mask %x pipe %c active pipes %x\n",
-		      dbuf_slice_mask,
-		      pipe_name(for_pipe), active_pipes);
-
 	/*
 	 * Figure out at which DBuf slice we start, i.e if we start at Dbuf S2
 	 * and slice size is 1024, the offset would be 1024
@@ -4191,8 +4187,10 @@ skl_ddb_get_pipe_allocation_limits(struct drm_i915_private *dev_priv,
 	alloc->start = offset + start;
 	alloc->end = offset + end;
 
-	DRM_DEBUG_KMS("Pipe %d ddb %d-%d\n", for_pipe,
-		      alloc->start, alloc->end);
+	drm_dbg_kms(&dev_priv->drm,
+		    "[CRTC:%d:%s] dbuf slices 0x%x, ddb (%d - %d), active pipes 0x%x\n",
+		    for_crtc->base.id, for_crtc->name,
+		    dbuf_slice_mask, alloc->start, alloc->end, active_pipes);
 
 	return 0;
 }
@@ -5706,7 +5704,10 @@ skl_ddb_add_affected_planes(const struct intel_crtc_state *old_crtc_state,
 static int
 skl_compute_ddb(struct intel_atomic_state *state)
 {
-	struct intel_crtc_state *old_crtc_state;
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	const struct intel_dbuf_state *old_dbuf_state;
+	const struct intel_dbuf_state *new_dbuf_state;
+	const struct intel_crtc_state *old_crtc_state;
 	struct intel_crtc_state *new_crtc_state;
 	struct intel_crtc *crtc;
 	int ret, i;
@@ -5723,6 +5724,17 @@ skl_compute_ddb(struct intel_atomic_state *state)
 			return ret;
 	}
 
+	old_dbuf_state = intel_atomic_get_old_dbuf_state(state);
+	new_dbuf_state = intel_atomic_get_new_dbuf_state(state);
+
+	if (new_dbuf_state &&
+	    new_dbuf_state->enabled_slices != old_dbuf_state->enabled_slices)
+		drm_dbg_kms(&dev_priv->drm,
+			    "Enabled dbuf slices 0x%x -> 0x%x (out of %d dbuf slices)\n",
+			    old_dbuf_state->enabled_slices,
+			    new_dbuf_state->enabled_slices,
+			    INTEL_INFO(dev_priv)->num_supported_dbuf_slices);
+
 	return 0;
 }