drm/nouveau/disp/dp: add support for eDP link rates

[linux-2.6-microblaze.git] / drivers / gpu / drm / nouveau / nouveau_dp.c

diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c
index 040ed88..3a288d0 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_dp.c
+++ b/drivers/gpu/drm/nouveau/nouveau_dp.c
@@ -147,6 +147,21 @@ nouveau_dp_detect(struct nouveau_connector *nv_connector,
        nv_encoder->dp.link_nr =
                dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK;
 
+       if (connector->connector_type == DRM_MODE_CONNECTOR_eDP && dpcd[DP_DPCD_REV] >= 0x13) {
+               struct drm_dp_aux *aux = &nv_connector->aux;
+               int ret, i;
+               u8 sink_rates[16];
+
+               ret = drm_dp_dpcd_read(aux, DP_SUPPORTED_LINK_RATES, sink_rates, sizeof(sink_rates));
+               if (ret == sizeof(sink_rates)) {
+                       for (i = 0; i < ARRAY_SIZE(sink_rates); i += 2) {
+                               int val = ((sink_rates[i + 1] << 8) | sink_rates[i]) * 200 / 10;
+                               if (val && (i == 0 || val > nv_encoder->dp.link_bw))
+                                       nv_encoder->dp.link_bw = val;
+                       }
+               }
+       }
+
        NV_DEBUG(drm, "display: %dx%d dpcd 0x%02x\n",
                 nv_encoder->dp.link_nr, nv_encoder->dp.link_bw,
                 dpcd[DP_DPCD_REV]);