[Intel-gfx] [PATCH 4/6] drm/i915/psr: Begin to handle PSR/PSR2 errors set by sink

[José Roberto de Souza]

Sink device will do a short pulse in HPD line when there is some
PSR/PSR2 error that needs to be handled by source, this is handling
the first and most simples error: DP_PSR_SINK_INTERNAL_ERROR.

Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/intel_dp.c  |  2 ++
 drivers/gpu/drm/i915/intel_drv.h |  1 +
 drivers/gpu/drm/i915/intel_psr.c | 31 +++++++++++++++++++++++++++++++
 3 files changed, 34 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index dacdd98bbb2e..955bf85e9b20 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -4549,6 +4549,8 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
 
 	intel_dp_check_link_status(intel_dp);
 
+	intel_psr_hpd_short_pulse_handle(intel_dp);
+
 	if (intel_dp->compliance.test_type == DP_TEST_LINK_TRAINING) {
 		DRM_DEBUG_KMS("Link Training Compliance Test requested\n");
 		/* Send a Hotplug Uevent to userspace to start modeset */
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 7adcd5955d1b..a0bd00787a98 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1890,6 +1890,7 @@ void intel_psr_compute_config(struct intel_dp *intel_dp,
  * It will also schedule a work to try to active PSR again.
  */
 void intel_psr_exit(struct intel_dp *intel_dp, bool wait_exit);
+void intel_psr_hpd_short_pulse_handle(struct intel_dp *intel_dp);
 
 /* intel_runtime_pm.c */
 int intel_power_domains_init(struct drm_i915_private *);
diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
index 0b889c85e8da..ab3713c2582b 100644
--- a/drivers/gpu/drm/i915/intel_psr.c
+++ b/drivers/gpu/drm/i915/intel_psr.c
@@ -985,3 +985,34 @@ void intel_psr_exit(struct intel_dp *intel_dp, bool wait_exit)
 out:
 	mutex_unlock(&dev_priv->psr.lock);
 }
+
+void intel_psr_hpd_short_pulse_handle(struct intel_dp *intel_dp)
+{
+	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+	struct drm_device *dev = intel_dig_port->base.base.dev;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_psr *psr = &dev_priv->psr;
+	uint8_t val;
+
+	if (!HAS_PSR(dev_priv))
+		return;
+
+	mutex_lock(&psr->lock);
+
+	if (psr->enabled != intel_dp)
+		goto out;
+
+	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PSR_STATUS, &val) != 1) {
+		DRM_DEBUG_KMS("PSR_STATUS read failed\n");
+		goto dpcd_read_error;
+	}
+
+	if ((val & DP_PSR_SINK_STATE_MASK) == DP_PSR_SINK_INTERNAL_ERROR)
+		psr->exit(intel_dp, false);
+
+	/* TODO: handle other PSR/PSR2 errors */
+dpcd_read_error:
+	intel_psr_active_schedule(psr, PSR_ACTIVE_DELAY_MSEC);
+out:
+	mutex_unlock(&psr->lock);
+}
-- 
2.16.2