[Intel-gfx] [PATCH 1/2] drm/i915: Enable TPS3/4 on all platforms that support them

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Stop using HBR2/3 support as a proxy for TPS3/4 support.
The two are no longer 1:1 in the hardware, arguably they
never were due to HSW ULX which does support TPS3 while
being limited to HBR1.

In more recent times GLK gained support for TPS4 while
being limited to HBR2. And on CNL+ some ports support
HBR3 while others are limited to HBR2, but all ports
support TPS4.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c       | 12 +++-----
 drivers/gpu/drm/i915/display/intel_dp.h       |  4 +--
 .../drm/i915/display/intel_dp_link_training.c | 29 +++++++------------
 drivers/gpu/drm/i915/display/intel_psr.c      |  2 +-
 4 files changed, 17 insertions(+), 30 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index c9b93c5706af..5ac182357fc9 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1799,18 +1799,14 @@ intel_dp_aux_init(struct intel_dp *intel_dp)
 	intel_dp->aux.transfer = intel_dp_aux_transfer;
 }
 
-bool intel_dp_source_supports_hbr2(struct intel_dp *intel_dp)
+bool intel_dp_source_supports_tps3(struct drm_i915_private *i915)
 {
-	int max_rate = intel_dp->source_rates[intel_dp->num_source_rates - 1];
-
-	return max_rate >= 540000;
+	return INTEL_GEN(i915) >= 9 || IS_BROADWELL(i915) || IS_HASWELL(i915);
 }
 
-bool intel_dp_source_supports_hbr3(struct intel_dp *intel_dp)
+bool intel_dp_source_supports_tps4(struct drm_i915_private *i915)
 {
-	int max_rate = intel_dp->source_rates[intel_dp->num_source_rates - 1];
-
-	return max_rate >= 810000;
+	return INTEL_GEN(i915) >= 10 || IS_GEMINILAKE(i915);
 }
 
 static void
diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
index 0a8950f744f6..d597a9848397 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.h
+++ b/drivers/gpu/drm/i915/display/intel_dp.h
@@ -94,8 +94,8 @@ intel_dp_set_signal_levels(struct intel_dp *intel_dp);
 void intel_dp_set_idle_link_train(struct intel_dp *intel_dp);
 void intel_dp_compute_rate(struct intel_dp *intel_dp, int port_clock,
 			   u8 *link_bw, u8 *rate_select);
-bool intel_dp_source_supports_hbr2(struct intel_dp *intel_dp);
-bool intel_dp_source_supports_hbr3(struct intel_dp *intel_dp);
+bool intel_dp_source_supports_tps3(struct drm_i915_private *i915);
+bool intel_dp_source_supports_tps4(struct drm_i915_private *i915);
 bool
 intel_dp_get_link_status(struct intel_dp *intel_dp, u8 *link_status);
 
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index 2493142a70e9..57c2089c9f5a 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -259,41 +259,32 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp)
  */
 static u32 intel_dp_training_pattern(struct intel_dp *intel_dp)
 {
+	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 	bool source_tps3, sink_tps3, source_tps4, sink_tps4;
 
-	/*
-	 * Intel platforms that support HBR3 also support TPS4. It is mandatory
-	 * for all downstream devices that support HBR3. There are no known eDP
-	 * panels that support TPS4 as of Feb 2018 as per VESA eDP_v1.4b_E1
-	 * specification.
-	 */
-	source_tps4 = intel_dp_source_supports_hbr3(intel_dp);
+	source_tps4 = intel_dp_source_supports_tps4(i915);
 	sink_tps4 = drm_dp_tps4_supported(intel_dp->dpcd);
 	if (source_tps4 && sink_tps4) {
 		return DP_TRAINING_PATTERN_4;
 	} else if (intel_dp->link_rate == 810000) {
 		if (!source_tps4)
-			drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
-				    "8.1 Gbps link rate without source HBR3/TPS4 support\n");
+			drm_dbg_kms(&i915->drm,
+				    "8.1 Gbps link rate without source TPS4 support\n");
 		if (!sink_tps4)
-			drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
+			drm_dbg_kms(&i915->drm,
 				    "8.1 Gbps link rate without sink TPS4 support\n");
 	}
-	/*
-	 * Intel platforms that support HBR2 also support TPS3. TPS3 support is
-	 * also mandatory for downstream devices that support HBR2. However, not
-	 * all sinks follow the spec.
-	 */
-	source_tps3 = intel_dp_source_supports_hbr2(intel_dp);
+
+	source_tps3 = intel_dp_source_supports_tps3(i915);
 	sink_tps3 = drm_dp_tps3_supported(intel_dp->dpcd);
 	if (source_tps3 && sink_tps3) {
 		return  DP_TRAINING_PATTERN_3;
 	} else if (intel_dp->link_rate >= 540000) {
 		if (!source_tps3)
-			drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
-				    ">=5.4/6.48 Gbps link rate without source HBR2/TPS3 support\n");
+			drm_dbg_kms(&i915->drm,
+				    ">=5.4/6.48 Gbps link rate without source TPS3 support\n");
 		if (!sink_tps3)
-			drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
+			drm_dbg_kms(&i915->drm,
 				    ">=5.4/6.48 Gbps link rate without sink TPS3 support\n");
 	}
 
diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index 611cb8d74811..5ba1aa2c6748 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -451,7 +451,7 @@ static u32 intel_psr1_get_tp_time(struct intel_dp *intel_dp)
 		val |= EDP_PSR_TP2_TP3_TIME_2500us;
 
 check_tp3_sel:
-	if (intel_dp_source_supports_hbr2(intel_dp) &&
+	if (intel_dp_source_supports_tps3(dev_priv) &&
 	    drm_dp_tps3_supported(intel_dp->dpcd))
 		val |= EDP_PSR_TP1_TP3_SEL;
 	else
-- 
2.26.2