1 files changed, 54 insertions, 9 deletions

diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
index 9ccff3011523..0b42ada338c8 100644
--- a/drivers/gpu/drm/i915/intel_psr.c
+++ b/drivers/gpu/drm/i915/intel_psr.c
@@ -225,7 +225,12 @@ static void hsw_psr_enable_sink(struct intel_dp *intel_dp)
 		   (aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT));
 	}
 
-	drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG, DP_PSR_ENABLE);
+	if (dev_priv->psr.link_standby)
+		drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG,
+				   DP_PSR_ENABLE | DP_PSR_MAIN_LINK_ACTIVE);
+	else
+		drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG,
+				   DP_PSR_ENABLE);
 }
 
 static void vlv_psr_enable_source(struct intel_dp *intel_dp)
@@ -280,6 +285,9 @@ static void hsw_psr_enable_source(struct intel_dp *intel_dp)
 	if (IS_HASWELL(dev))
 		val |= EDP_PSR_MIN_LINK_ENTRY_TIME_8_LINES;
 
+	if (dev_priv->psr.link_standby)
+		val |= EDP_PSR_LINK_STANDBY;
+
 	I915_WRITE(EDP_PSR_CTL, val |
 		   max_sleep_time << EDP_PSR_MAX_SLEEP_TIME_SHIFT |
 		   idle_frames << EDP_PSR_IDLE_FRAME_SHIFT |
@@ -304,8 +312,15 @@ static bool intel_psr_match_conditions(struct intel_dp *intel_dp)
 
 	dev_priv->psr.source_ok = false;
 
-	if (IS_HASWELL(dev) && dig_port->port != PORT_A) {
-		DRM_DEBUG_KMS("HSW ties PSR to DDI A (eDP)\n");
+	/*
+	 * HSW spec explicitly says PSR is tied to port A.
+	 * BDW+ platforms with DDI implementation of PSR have different
+	 * PSR registers per transcoder and we only implement transcoder EDP
+	 * ones. Since by Display design transcoder EDP is tied to port A
+	 * we can safely escape based on the port A.
+	 */
+	if (HAS_DDI(dev) && dig_port->port != PORT_A) {
+		DRM_DEBUG_KMS("PSR condition failed: Port not supported\n");
 		return false;
 	}
 
@@ -314,6 +329,12 @@ static bool intel_psr_match_conditions(struct intel_dp *intel_dp)
 		return false;
 	}
 
+	if ((IS_VALLEYVIEW(dev) || IS_CHERRYVIEW(dev)) &&
+	    !dev_priv->psr.link_standby) {
+		DRM_ERROR("PSR condition failed: Link off requested but not supported on this platform\n");
+		return false;
+	}
+
 	if (IS_HASWELL(dev) &&
 	    I915_READ(HSW_STEREO_3D_CTL(intel_crtc->config->cpu_transcoder)) &
 		      S3D_ENABLE) {
@@ -327,12 +348,6 @@ static bool intel_psr_match_conditions(struct intel_dp *intel_dp)
 		return false;
 	}
 
-	if (!IS_VALLEYVIEW(dev) && !IS_CHERRYVIEW(dev) &&
-	    ((dev_priv->vbt.psr.full_link) || (dig_port->port != PORT_A))) {
-		DRM_DEBUG_KMS("PSR condition failed: Link Standby requested/needed but not supported on this platform\n");
-		return false;
-	}
-
 	dev_priv->psr.source_ok = true;
 	return true;
 }
@@ -763,6 +778,36 @@ void intel_psr_init(struct drm_device *dev)
 	dev_priv->psr_mmio_base = IS_HASWELL(dev_priv) ?
 		HSW_EDP_PSR_BASE : BDW_EDP_PSR_BASE;
 
+	/* Per platform default */
+	if (i915.enable_psr == -1) {
+		if (IS_HASWELL(dev) || IS_BROADWELL(dev) ||
+		    IS_VALLEYVIEW(dev) || IS_CHERRYVIEW(dev))
+			i915.enable_psr = 1;
+		else
+			i915.enable_psr = 0;
+	}
+
+	/* Set link_standby x link_off defaults */
+	if (IS_HASWELL(dev) || IS_BROADWELL(dev))
+		/* HSW and BDW require workarounds that we don't implement. */
+		dev_priv->psr.link_standby = false;
+	else if (IS_VALLEYVIEW(dev) || IS_CHERRYVIEW(dev))
+		/* On VLV and CHV only standby mode is supported. */
+		dev_priv->psr.link_standby = true;
+	else
+		/* For new platforms let's respect VBT back again */
+		dev_priv->psr.link_standby = dev_priv->vbt.psr.full_link;
+
+	/* Override link_standby x link_off defaults */
+	if (i915.enable_psr == 2 && !dev_priv->psr.link_standby) {
+		DRM_DEBUG_KMS("PSR: Forcing link standby\n");
+		dev_priv->psr.link_standby = true;
+	}
+	if (i915.enable_psr == 3 && dev_priv->psr.link_standby) {
+		DRM_DEBUG_KMS("PSR: Forcing main link off\n");
+		dev_priv->psr.link_standby = false;
+	}
+
 	INIT_DELAYED_WORK(&dev_priv->psr.work, intel_psr_work);
 	mutex_init(&dev_priv->psr.lock);
 }