supported_rates);
 }
 
+static void snprintf_int_array(char *str, size_t len,
+                              const int *array, int nelem)
+{
+       int i;
+
+       str[0] = '\0';
+
+       for (i = 0; i < nelem; i++) {
+               int r = snprintf(str, len, "%d,", array[i]);
+               if (r >= len)
+                       return;
+               str += r;
+               len -= r;
+       }
+}
+
+static void intel_dp_print_rates(struct intel_dp *intel_dp)
+{
+       struct drm_device *dev = intel_dp_to_dev(intel_dp);
+       const int *source_rates, *sink_rates;
+       int source_len, sink_len, supported_len;
+       int supported_rates[DP_MAX_SUPPORTED_RATES];
+       char str[128]; /* FIXME: too big for stack? */
+
+       if ((drm_debug & DRM_UT_KMS) == 0)
+               return;
+
+       source_len = intel_dp_source_rates(dev, &source_rates);
+       snprintf_int_array(str, sizeof(str), source_rates, source_len);
+       DRM_DEBUG_KMS("source rates: %s\n", str);
+
+       sink_len = intel_dp_sink_rates(intel_dp, &sink_rates);
+       snprintf_int_array(str, sizeof(str), sink_rates, sink_len);
+       DRM_DEBUG_KMS("sink rates: %s\n", str);
+
+       supported_len = intel_supported_rates(intel_dp, supported_rates);
+       snprintf_int_array(str, sizeof(str), supported_rates, supported_len);
+       DRM_DEBUG_KMS("supported rates: %s\n", str);
+}
+
 static int rate_to_index(int find, const int *rates)
 {
        int i = 0;
                }
                intel_dp->num_supported_rates = i;
        }
+
+       intel_dp_print_rates(intel_dp);
+
        if (!(intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT] &
              DP_DWN_STRM_PORT_PRESENT))
                return true; /* native DP sink */