@@ -14614,7 +14614,13 @@ static int intel_atomic_check_planes(struct intel_atomic_state *state)
old_active_planes = old_crtc_state->active_planes & ~BIT(PLANE_CURSOR);
new_active_planes = new_crtc_state->active_planes & ~BIT(PLANE_CURSOR);
- if (hweight8(old_active_planes) == hweight8(new_active_planes))
+ /*
+ * Not only the number of planes, but if the plane configuration had
+ * changed might already mean we need to recompute min CDCLK,
+ * because different planes might consume different amount of Dbuf bandwidth
+ * according to formula: Bw per plane = Pixel rate * bpp * pipe/plane scale factor
+ */
+ if (old_active_planes == new_active_planes)
continue;
ret = intel_crtc_add_planes_to_state(state, crtc, new_active_planes);