diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 88cc1e219a13..ad344daaab89 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2975,25 +2975,69 @@ skl_plane_relative_data_rate(const struct intel_crtc_state *cstate,
  *   3 * 4096 * 8192  * 4 < 2^32
  */
 static unsigned int
-skl_get_total_relative_data_rate(struct intel_crtc_state *cstate)
+skl_get_total_relative_data_rate(struct intel_crtc_state *intel_cstate)
 {
-	struct intel_crtc *intel_crtc = to_intel_crtc(cstate->base.crtc);
-	struct drm_device *dev = intel_crtc->base.dev;
+	struct drm_crtc_state *cstate = &intel_cstate->base;
+	struct drm_atomic_state *state = cstate->state;
+	struct drm_crtc *crtc = cstate->crtc;
+	struct drm_device *dev = crtc->dev;
+	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
 	const struct intel_plane *intel_plane;
 	unsigned int rate, total_data_rate = 0;
+	int id;
 
 	/* Calculate and cache data rate for each plane */
-	for_each_intel_plane_on_crtc(dev, intel_crtc, intel_plane) {
-		const struct drm_plane_state *pstate = intel_plane->base.state;
-		int id = skl_wm_plane_id(intel_plane);
+	/*
+	 * FIXME: At the moment this function can be called on either an
+	 * in-flight or a committed state object.  If it's in-flight then we
+	 * only want to re-calculate the plane data rate for planes that are
+	 * part of the transaction (i.e., we don't want to grab any additional
+	 * plane states if we don't have to).  If we're operating on committed
+	 * state, we'll just go ahead and recalculate the plane data rate for
+	 * all planes.
+	 *
+	 * Once we finish moving our DDB allocation to the atomic check phase,
+	 * we'll only be calling this function on in-flight state objects, so
+	 * the 'else' branch here will go away.
+	 */
+	if (state) {
+		struct drm_plane *plane;
+		struct drm_plane_state *pstate;
+		int i;
 
-		/* packed/uv */
-		rate = skl_plane_relative_data_rate(cstate, pstate, 0);
-		cstate->wm.skl.plane_data_rate[id] = rate;
+		for_each_plane_in_state(state, plane, pstate, i) {
+			intel_plane = to_intel_plane(plane);
+			id = skl_wm_plane_id(intel_plane);
 
-		/* y-plane */
-		rate = skl_plane_relative_data_rate(cstate, pstate, 1);
-		cstate->wm.skl.plane_y_data_rate[id] = rate;
+			if (intel_plane->pipe != intel_crtc->pipe)
+				continue;
+
+			/* packed/uv */
+			rate = skl_plane_relative_data_rate(intel_cstate,
+							    pstate, 0);
+			intel_cstate->wm.skl.plane_data_rate[id] = rate;
+
+			/* y-plane */
+			rate = skl_plane_relative_data_rate(intel_cstate,
+							    pstate, 1);
+			intel_cstate->wm.skl.plane_y_data_rate[id] = rate;
+		}
+	} else {
+		for_each_intel_plane_on_crtc(dev, intel_crtc, intel_plane) {
+			const struct drm_plane_state *pstate =
+				intel_plane->base.state;
+			int id = skl_wm_plane_id(intel_plane);
+
+			/* packed/uv */
+			rate = skl_plane_relative_data_rate(intel_cstate,
+							    pstate, 0);
+			intel_cstate->wm.skl.plane_data_rate[id] = rate;
+
+			/* y-plane */
+			rate = skl_plane_relative_data_rate(intel_cstate,
+							    pstate, 1);
+			intel_cstate->wm.skl.plane_y_data_rate[id] = rate;
+		}
 	}
 
 	/* Calculate CRTC's total data rate from cached values */
@@ -3001,10 +3045,12 @@ skl_get_total_relative_data_rate(struct intel_crtc_state *cstate)
 		int id = skl_wm_plane_id(intel_plane);
 
 		/* packed/uv */
-		total_data_rate += cstate->wm.skl.plane_data_rate[id];
-		total_data_rate += cstate->wm.skl.plane_y_data_rate[id];
+		total_data_rate += intel_cstate->wm.skl.plane_data_rate[id];
+		total_data_rate += intel_cstate->wm.skl.plane_y_data_rate[id];
 	}
 
+	WARN_ON(cstate->plane_mask && total_data_rate == 0);
+
 	return total_data_rate;
 }