vco = best_clock.vco;
        } else if (encoder->type == INTEL_OUTPUT_DP ||
-                  encoder->type == INTEL_OUTPUT_EDP) {
+                  encoder->type == INTEL_OUTPUT_EDP ||
+                  encoder->type == INTEL_OUTPUT_DP_MST) {
                int i;
 
                clk_div = bxt_dp_clk_val[0];
        crtc_state->dpll_hw_state.pcsdw12 =
                LANESTAGGER_STRAP_OVRD | lanestagger;
 
-       intel_dig_port = enc_to_dig_port(&encoder->base);
+       if (encoder->type == INTEL_OUTPUT_DP_MST) {
+               struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
+
+               intel_dig_port = intel_mst->primary;
+       } else
+               intel_dig_port = enc_to_dig_port(&encoder->base);
 
        /* 1:1 mapping between ports and PLLs */
        i = (enum intel_dpll_id) intel_dig_port->port;