[Intel-gfx] [PATCH 6/6] drm/i915/psr/hsw+: Enable CRC check in the static frame on the sink side

[José Roberto de Souza]

Sink can be configured to calculate the CRC over the static frame and
compare with the CRC calculated and transmited in the VSC SDP by
source, if there is a mismatch sink will do a short pulse in HPD
and set DP_PSR_LINK_CRC_ERROR on DP_PSR_ERROR_STATUS.

Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h  |  1 +
 drivers/gpu/drm/i915/intel_psr.c | 15 +++++++--------
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index f36e839b4b4f..ca68eef8d90a 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4122,6 +4122,7 @@ enum {
 #define   EDP_PSR_SKIP_AUX_EXIT			(1<<12)
 #define   EDP_PSR_TP1_TP2_SEL			(0<<11)
 #define   EDP_PSR_TP1_TP3_SEL			(1<<11)
+#define   EDP_PSR_CRC_ENABLE			(1<<10)
 #define   EDP_PSR_TP2_TP3_TIME_500us		(0<<8)
 #define   EDP_PSR_TP2_TP3_TIME_100us		(1<<8)
 #define   EDP_PSR_TP2_TP3_TIME_2500us		(2<<8)
diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
index 4e73edf1ea5b..f6af8e8039c9 100644
--- a/drivers/gpu/drm/i915/intel_psr.c
+++ b/drivers/gpu/drm/i915/intel_psr.c
@@ -160,6 +160,7 @@ static void hsw_psr_enable_sink(struct intel_dp *intel_dp)
 	enum port port = dig_port->base.port;
 	u32 aux_ctl;
 	int i;
+	uint8_t val;
 
 	BUILD_BUG_ON(sizeof(aux_msg) > 20);
 
@@ -175,12 +176,10 @@ static void hsw_psr_enable_sink(struct intel_dp *intel_dp)
 		drm_dp_dpcd_writeb(&intel_dp->aux,
 				DP_RECEIVER_ALPM_CONFIG,
 				DP_ALPM_ENABLE);
+	val = DP_PSR_ENABLE | DP_PSR_CRC_VERIFICATION;
 	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);
+		val |= DP_PSR_MAIN_LINK_ACTIVE;
+	drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG, val);
 
 	aux_ctl_reg = psr_aux_ctl_reg(dev_priv, port);
 
@@ -241,7 +240,7 @@ static void hsw_activate_psr1(struct intel_dp *intel_dp)
 	 * with the 5 or 6 idle patterns.
 	 */
 	uint32_t idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
-	uint32_t val = EDP_PSR_ENABLE;
+	uint32_t val = EDP_PSR_ENABLE | EDP_PSR_CRC_ENABLE;
 
 	val |= max_sleep_time << EDP_PSR_MAX_SLEEP_TIME_SHIFT;
 	val |= idle_frames << EDP_PSR_IDLE_FRAME_SHIFT;
@@ -1015,12 +1014,12 @@ void intel_psr_hpd_short_pulse_handle(struct intel_dp *intel_dp)
 		goto dpcd_read_error;
 	}
 
-	if (val & DP_PSR_RFB_STORAGE_ERROR)
+	if (val & (DP_PSR_RFB_STORAGE_ERROR | DP_PSR_LINK_CRC_ERROR))
 		dev_priv->psr.exit(intel_dp, false);
 	/* clear status register */
 	drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_ERROR_STATUS, val);
 
-	/* TODO: handle other PSR/PSR2 errors */
+	/* TODO: handle PSR2 errors */
 dpcd_read_error:
 	intel_psr_active_schedule(psr, PSR_ACTIVE_DELAY_MSEC);
 out:
-- 
2.16.2