diff --git a/drivers/gpu/drm/i915/display/intel_lt_phy.c b/drivers/gpu/drm/i915/display/intel_lt_phy.c
index f768804122c1..e1c95f58b6ae 100644
--- a/drivers/gpu/drm/i915/display/intel_lt_phy.c
+++ b/drivers/gpu/drm/i915/display/intel_lt_phy.c
@@ -2176,6 +2176,14 @@ intel_lt_phy_pll_compare_hw_state(const struct intel_lt_phy_pll_state *a,
 	return false;
 }
 
+static bool intel_lt_phy_pll_is_enabled(struct intel_encoder *encoder)
+{
+	struct intel_display *display = to_intel_display(encoder);
+
+	return intel_de_read(display, XELPDP_PORT_CLOCK_CTL(display, encoder->port)) &
+			     XELPDP_LANE_PCLK_PLL_ACK(0);
+}
+
 void intel_lt_phy_pll_readout_hw_state(struct intel_encoder *encoder,
 				       const struct intel_crtc_state *crtc_state,
 				       struct intel_lt_phy_pll_state *pll_state)
@@ -2185,6 +2193,9 @@ void intel_lt_phy_pll_readout_hw_state(struct intel_encoder *encoder,
 	struct ref_tracker *wakeref;
 	int i, j, k;
 
+	if (!intel_lt_phy_pll_is_enabled(encoder))
+		return;
+
 	pll_state->tbt_mode = intel_tc_port_in_tbt_alt_mode(enc_to_dig_port(encoder));
 	if (pll_state->tbt_mode)
 		return;