Merge tag 'topic/phy-compliance-2020-04-08' of git://anongit.freedesktop.org/drm/drm-misc into drm-intel-next-queued

Topic pull request for topic/phy-compliance:
- Standardize DP_PHY_TEST_PATTERN name.
- Add support for setting/getting test pattern from sink.
- Implement DP PHY compliance to i915.

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/efb3d0d9-2cf7-046b-3a9b-2548d086258e@linux.intel.com
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

1 files changed, 94 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 8ba4531e808d..612a59ec8116 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -1535,3 +1535,97 @@ int drm_dp_dsc_sink_supported_input_bpcs(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_S
 	return num_bpc;
 }
 EXPORT_SYMBOL(drm_dp_dsc_sink_supported_input_bpcs);
+
+/**
+ * drm_dp_get_phy_test_pattern() - get the requested pattern from the sink.
+ * @aux: DisplayPort AUX channel
+ * @data: DP phy compliance test parameters.
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_get_phy_test_pattern(struct drm_dp_aux *aux,
+				struct drm_dp_phy_test_params *data)
+{
+	int err;
+	u8 rate, lanes;
+
+	err = drm_dp_dpcd_readb(aux, DP_TEST_LINK_RATE, &rate);
+	if (err < 0)
+		return err;
+	data->link_rate = drm_dp_bw_code_to_link_rate(rate);
+
+	err = drm_dp_dpcd_readb(aux, DP_TEST_LANE_COUNT, &lanes);
+	if (err < 0)
+		return err;
+	data->num_lanes = lanes & DP_MAX_LANE_COUNT_MASK;
+
+	if (lanes & DP_ENHANCED_FRAME_CAP)
+		data->enhanced_frame_cap = true;
+
+	err = drm_dp_dpcd_readb(aux, DP_PHY_TEST_PATTERN, &data->phy_pattern);
+	if (err < 0)
+		return err;
+
+	switch (data->phy_pattern) {
+	case DP_PHY_TEST_PATTERN_80BIT_CUSTOM:
+		err = drm_dp_dpcd_read(aux, DP_TEST_80BIT_CUSTOM_PATTERN_7_0,
+				       &data->custom80, sizeof(data->custom80));
+		if (err < 0)
+			return err;
+
+		break;
+	case DP_PHY_TEST_PATTERN_CP2520:
+		err = drm_dp_dpcd_read(aux, DP_TEST_HBR2_SCRAMBLER_RESET,
+				       &data->hbr2_reset,
+				       sizeof(data->hbr2_reset));
+		if (err < 0)
+			return err;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_dp_get_phy_test_pattern);
+
+/**
+ * drm_dp_set_phy_test_pattern() - set the pattern to the sink.
+ * @aux: DisplayPort AUX channel
+ * @data: DP phy compliance test parameters.
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_set_phy_test_pattern(struct drm_dp_aux *aux,
+				struct drm_dp_phy_test_params *data, u8 dp_rev)
+{
+	int err, i;
+	u8 link_config[2];
+	u8 test_pattern;
+
+	link_config[0] = drm_dp_link_rate_to_bw_code(data->link_rate);
+	link_config[1] = data->num_lanes;
+	if (data->enhanced_frame_cap)
+		link_config[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
+	err = drm_dp_dpcd_write(aux, DP_LINK_BW_SET, link_config, 2);
+	if (err < 0)
+		return err;
+
+	test_pattern = data->phy_pattern;
+	if (dp_rev < 0x12) {
+		test_pattern = (test_pattern << 2) &
+			       DP_LINK_QUAL_PATTERN_11_MASK;
+		err = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET,
+					 test_pattern);
+		if (err < 0)
+			return err;
+	} else {
+		for (i = 0; i < data->num_lanes; i++) {
+			err = drm_dp_dpcd_writeb(aux,
+						 DP_LINK_QUAL_LANE0_SET + i,
+						 test_pattern);
+			if (err < 0)
+				return err;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_dp_set_phy_test_pattern);