diff mbox series

[11/26] drm/dp: Pimp drm_dp_downstream_max_bpc()

Message ID 20200203151343.14378-12-ville.syrjala@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series drm/i915: Pimp DP DFP handling | expand

Commit Message

Ville Syrjälä Feb. 3, 2020, 3:13 p.m. UTC 
From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Deal with more cases in drm_dp_downstream_max_bpc():
- DPCD 1.0 -> assume 8bpc for non-DP
- DPCD 1.1+ DP (or DP++ with DP sink) -> allow anything
- DPCD 1.1+ TMDS -> check the caps, assume 8bpc if the value is crap
- anything else -> assume 8bpc

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
 drivers/gpu/drm/drm_dp_helper.c         | 65 ++++++++++++++++---------
 drivers/gpu/drm/i915/display/intel_dp.c |  2 +-
 drivers/gpu/drm/i915/i915_debugfs.c     |  4 +-
 include/drm/drm_dp_helper.h             | 10 ++--
 4 files changed, 52 insertions(+), 29 deletions(-)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index bdb7ae3ce32e..7164b9d274e1 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -456,32 +456,44 @@  int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
 EXPORT_SYMBOL(drm_dp_downstream_max_clock);
 
 /**
- * drm_dp_downstream_max_bpc() - extract branch device max
- *                               bits per component
- * @dpcd: DisplayPort configuration data
- * @port_cap: port capabilities
- *
- * Returns max bpc on success or 0 if max bpc not defined
- */
+  * drm_dp_downstream_max_bpc() - extract downstream facing port max
+  *                               bits per component
+  * @dpcd: DisplayPort configuration data
+  * @port_cap: downstream facing port capabilities
+  * @edid: EDID
+  *
+  * Returns max bpc on success or 0 if max bpc not defined
+  */
 int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
-			      const u8 port_cap[4])
+			      const u8 port_cap[4],
+			      const struct edid *edid)
 {
-	int type = port_cap[0] & DP_DS_PORT_TYPE_MASK;
-	bool detailed_cap_info = dpcd[DP_DOWNSTREAMPORT_PRESENT] &
-		DP_DETAILED_CAP_INFO_AVAILABLE;
-	int bpc;
-
-	if (!detailed_cap_info)
+	if (!drm_dp_is_branch(dpcd))
 		return 0;
 
-	switch (type) {
-	case DP_DS_PORT_TYPE_VGA:
-	case DP_DS_PORT_TYPE_DVI:
-	case DP_DS_PORT_TYPE_HDMI:
+	if (dpcd[DP_DPCD_REV] < 0x11) {
+		switch (dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_TYPE_MASK) {
+		case DP_DWN_STRM_PORT_TYPE_DP:
+			return 0;
+		default:
+			return 8;
+		}
+	}
+
+	switch (port_cap[0] & DP_DS_PORT_TYPE_MASK) {
+	case DP_DS_PORT_TYPE_DP:
+		return 0;
 	case DP_DS_PORT_TYPE_DP_DUALMODE:
-		bpc = port_cap[2] & DP_DS_MAX_BPC_MASK;
+		if (is_edid_digital_input_dp(edid))
+			return 0;
+		/* fall through */
+	case DP_DS_PORT_TYPE_HDMI:
+	case DP_DS_PORT_TYPE_DVI:
+	case DP_DS_PORT_TYPE_VGA:
+		if ((dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DETAILED_CAP_INFO_AVAILABLE) == 0)
+			return 8;
 
-		switch (bpc) {
+		switch (port_cap[2] & DP_DS_MAX_BPC_MASK) {
 		case DP_DS_8BPC:
 			return 8;
 		case DP_DS_10BPC:
@@ -490,10 +502,12 @@  int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
 			return 12;
 		case DP_DS_16BPC:
 			return 16;
+		default:
+			return 8;
 		}
-		/* fall through */
+		break;
 	default:
-		return 0;
+		return 8;
 	}
 }
 EXPORT_SYMBOL(drm_dp_downstream_max_bpc);
@@ -516,12 +530,15 @@  EXPORT_SYMBOL(drm_dp_downstream_id);
  * @m: pointer for debugfs file
  * @dpcd: DisplayPort configuration data
  * @port_cap: port capabilities
+ * @edid: EDID
  * @aux: DisplayPort AUX channel
  *
  */
 void drm_dp_downstream_debug(struct seq_file *m,
 			     const u8 dpcd[DP_RECEIVER_CAP_SIZE],
-			     const u8 port_cap[4], struct drm_dp_aux *aux)
+			     const u8 port_cap[4],
+			     const struct edid *edid,
+			     struct drm_dp_aux *aux)
 {
 	bool detailed_cap_info = dpcd[DP_DOWNSTREAMPORT_PRESENT] &
 				 DP_DETAILED_CAP_INFO_AVAILABLE;
@@ -588,7 +605,7 @@  void drm_dp_downstream_debug(struct seq_file *m,
 				seq_printf(m, "\t\tMax TMDS clock: %d kHz\n", clk);
 		}
 
-		bpc = drm_dp_downstream_max_bpc(dpcd, port_cap);
+		bpc = drm_dp_downstream_max_bpc(dpcd, port_cap, edid);
 
 		if (bpc > 0)
 			seq_printf(m, "\t\tMax bpc: %d\n", bpc);
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 5fab7ab97815..706750f9379e 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5665,7 +5665,7 @@  intel_dp_set_edid(struct intel_dp *intel_dp)
 
 	intel_dp->dfp.max_bpc =
 		drm_dp_downstream_max_bpc(intel_dp->dpcd,
-					  intel_dp->downstream_ports);
+					  intel_dp->downstream_ports, edid);
 
 	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] DFP max bpc %d\n",
 		      connector->base.base.id, connector->base.name,
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index e75e8212f03b..cfef38932f65 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2393,6 +2393,7 @@  static void intel_dp_info(struct seq_file *m,
 {
 	struct intel_encoder *intel_encoder = intel_attached_encoder(intel_connector);
 	struct intel_dp *intel_dp = enc_to_intel_dp(intel_encoder);
+	const struct drm_property_blob *edid = intel_connector->base.edid_blob_ptr;
 
 	seq_printf(m, "\tDPCD rev: %x\n", intel_dp->dpcd[DP_DPCD_REV]);
 	seq_printf(m, "\taudio support: %s\n", yesno(intel_dp->has_audio));
@@ -2400,7 +2401,8 @@  static void intel_dp_info(struct seq_file *m,
 		intel_panel_info(m, &intel_connector->panel);
 
 	drm_dp_downstream_debug(m, intel_dp->dpcd, intel_dp->downstream_ports,
-				&intel_dp->aux);
+				edid ? edid->data : NULL, &intel_dp->aux);
+
 	if (intel_connector->hdcp.shim) {
 		seq_puts(m, "\tHDCP version: ");
 		intel_hdcp_info(m, intel_connector);
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index 958db298adc7..62637acaefee 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -1483,10 +1483,14 @@  bool drm_dp_downstream_is_tmds(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
 int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
 				const u8 port_cap[4]);
 int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
-			      const u8 port_cap[4]);
+			      const u8 port_cap[4],
+			      const struct edid *edid);
 int drm_dp_downstream_id(struct drm_dp_aux *aux, char id[6]);
-void drm_dp_downstream_debug(struct seq_file *m, const u8 dpcd[DP_RECEIVER_CAP_SIZE],
-			     const u8 port_cap[4], struct drm_dp_aux *aux);
+void drm_dp_downstream_debug(struct seq_file *m,
+			     const u8 dpcd[DP_RECEIVER_CAP_SIZE],
+			     const u8 port_cap[4],
+			     const struct edid *edid,
+			     struct drm_dp_aux *aux);
 
 void drm_dp_remote_aux_init(struct drm_dp_aux *aux);
 void drm_dp_aux_init(struct drm_dp_aux *aux);