diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
index 354a9dba6440..4e143082dca1 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.c
@@ -39,6 +39,7 @@
 #include "intel_pcode.h"
 #include "intel_psr.h"
 #include "intel_vdsc.h"
+#include "skl_watermark.h"
 #include "vlv_sideband.h"
 
 /**
@@ -1889,6 +1890,16 @@ static u32 xe2lpd_mdclk_source_sel(struct drm_i915_private *i915)
 	return MDCLK_SOURCE_SEL_CD2XCLK;
 }
 
+u8 intel_mdclk_cdclk_ratio(struct drm_i915_private *i915,
+			   const struct intel_cdclk_config *cdclk_config)
+{
+	if (mdclk_source_is_cdclk_pll(i915))
+		return DIV_ROUND_UP(cdclk_config->vco, cdclk_config->cdclk);
+
+	/* Otherwise, source for MDCLK is CD2XCLK. */
+	return 2;
+}
+
 static bool cdclk_compute_crawl_and_squash_midpoint(struct drm_i915_private *i915,
 						    const struct intel_cdclk_config *old_cdclk_config,
 						    const struct intel_cdclk_config *new_cdclk_config,
@@ -3278,6 +3289,15 @@ int intel_modeset_calc_cdclk(struct intel_atomic_state *state)
 			    "Modeset required for cdclk change\n");
 	}
 
+	if (intel_mdclk_cdclk_ratio(dev_priv, &old_cdclk_state->actual) !=
+	    intel_mdclk_cdclk_ratio(dev_priv, &new_cdclk_state->actual)) {
+		u8 ratio = intel_mdclk_cdclk_ratio(dev_priv, &new_cdclk_state->actual);
+
+		ret = intel_dbuf_state_set_mdclk_cdclk_ratio(state, ratio);
+		if (ret)
+			return ret;
+	}
+
 	drm_dbg_kms(&dev_priv->drm,
 		    "New cdclk calculated to be logical %u kHz, actual %u kHz\n",
 		    new_cdclk_state->logical.cdclk,
diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.h b/drivers/gpu/drm/i915/display/intel_cdclk.h
index fa301495e7f1..8e6e302bd599 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.h
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.h
@@ -62,6 +62,8 @@ void intel_update_cdclk(struct drm_i915_private *dev_priv);
 u32 intel_read_rawclk(struct drm_i915_private *dev_priv);
 bool intel_cdclk_clock_changed(const struct intel_cdclk_config *a,
 			       const struct intel_cdclk_config *b);
+u8 intel_mdclk_cdclk_ratio(struct drm_i915_private *i915,
+			   const struct intel_cdclk_config *cdclk_config);
 void intel_set_cdclk_pre_plane_update(struct intel_atomic_state *state);
 void intel_set_cdclk_post_plane_update(struct intel_atomic_state *state);
 void intel_cdclk_dump_config(struct drm_i915_private *i915,
diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
index d9e49cd60d3a..4410e21888ad 100644
--- a/drivers/gpu/drm/i915/display/skl_watermark.c
+++ b/drivers/gpu/drm/i915/display/skl_watermark.c
@@ -3057,6 +3057,8 @@ static void skl_wm_get_hw_state(struct drm_i915_private *i915)
 	if (HAS_MBUS_JOINING(i915))
 		dbuf_state->joined_mbus = intel_de_read(i915, MBUS_CTL) & MBUS_JOIN;
 
+	dbuf_state->mdclk_cdclk_ratio = intel_mdclk_cdclk_ratio(i915, &i915->display.cdclk.hw);
+
 	for_each_intel_crtc(&i915->drm, crtc) {
 		struct intel_crtc_state *crtc_state =
 			to_intel_crtc_state(crtc->base.state);
@@ -3530,6 +3532,19 @@ int intel_dbuf_init(struct drm_i915_private *i915)
 	return 0;
 }
 
+int intel_dbuf_state_set_mdclk_cdclk_ratio(struct intel_atomic_state *state, u8 ratio)
+{
+	struct intel_dbuf_state *dbuf_state;
+
+	dbuf_state = intel_atomic_get_dbuf_state(state);
+	if (IS_ERR(dbuf_state))
+		return PTR_ERR(dbuf_state);
+
+	dbuf_state->mdclk_cdclk_ratio = ratio;
+
+	return intel_atomic_lock_global_state(&dbuf_state->base);
+}
+
 static void intel_dbuf_mdclk_cdclk_ratio_update(struct drm_i915_private *i915,
 						u8 ratio,
 						bool joined_mbus)
@@ -3574,7 +3589,8 @@ static void update_mbus_pre_enable(struct intel_atomic_state *state)
 		     MBUS_HASHING_MODE_MASK | MBUS_JOIN |
 		     MBUS_JOIN_PIPE_SELECT_MASK, mbus_ctl);
 
-	intel_dbuf_mdclk_cdclk_ratio_update(i915, 2, dbuf_state->joined_mbus);
+	intel_dbuf_mdclk_cdclk_ratio_update(i915, dbuf_state->mdclk_cdclk_ratio,
+					    dbuf_state->joined_mbus);
 }
 
 void intel_dbuf_pre_plane_update(struct intel_atomic_state *state)
diff --git a/drivers/gpu/drm/i915/display/skl_watermark.h b/drivers/gpu/drm/i915/display/skl_watermark.h
index e3d1d74a7b17..fed4d12df584 100644
--- a/drivers/gpu/drm/i915/display/skl_watermark.h
+++ b/drivers/gpu/drm/i915/display/skl_watermark.h
@@ -58,6 +58,7 @@ struct intel_dbuf_state {
 	u8 slices[I915_MAX_PIPES];
 	u8 enabled_slices;
 	u8 active_pipes;
+	u8 mdclk_cdclk_ratio;
 	bool joined_mbus;
 };
 
@@ -71,6 +72,8 @@ intel_atomic_get_dbuf_state(struct intel_atomic_state *state);
 	to_intel_dbuf_state(intel_atomic_get_new_global_obj_state(state, &to_i915(state->base.dev)->display.dbuf.obj))
 
 int intel_dbuf_init(struct drm_i915_private *i915);
+int intel_dbuf_state_set_mdclk_cdclk_ratio(struct intel_atomic_state *state, u8 ratio);
+
 void intel_dbuf_pre_plane_update(struct intel_atomic_state *state);
 void intel_dbuf_post_plane_update(struct intel_atomic_state *state);
 void intel_mbus_dbox_update(struct intel_atomic_state *state);