[Intel-gfx] [PATCH 1/4] drm/i915/psr: Always wait for idle state when disabling PSR

[José Roberto de Souza]

It should always wait for idle state when disabling PSR because PSR
could be inactive due a call to intel_psr_exit() and while PSR is
still being disabled asynchronously userspace could change the
modeset causing a call to psr_disable() that will not wait for PSR
idle and then PSR will be enabled again while PSR is still not idle.

Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/intel_psr.c | 43 +++++++++++++++-----------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
index 423cdf84059c..cd9a60d1efa1 100644
--- a/drivers/gpu/drm/i915/intel_psr.c
+++ b/drivers/gpu/drm/i915/intel_psr.c
@@ -661,40 +661,37 @@ static void
 intel_psr_disable_source(struct intel_dp *intel_dp)
 {
 	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
+	i915_reg_t psr_status;
+	u32 psr_status_mask;
 
 	if (dev_priv->psr.active) {
-		i915_reg_t psr_status;
-		u32 psr_status_mask;
-
-		if (dev_priv->psr.psr2_enabled) {
-			psr_status = EDP_PSR2_STATUS;
-			psr_status_mask = EDP_PSR2_STATUS_STATE_MASK;
-
+		if (dev_priv->psr.psr2_enabled)
 			I915_WRITE(EDP_PSR2_CTL,
-				   I915_READ(EDP_PSR2_CTL) &
-				   ~(EDP_PSR2_ENABLE | EDP_SU_TRACK_ENABLE));
-
-		} else {
-			psr_status = EDP_PSR_STATUS;
-			psr_status_mask = EDP_PSR_STATUS_STATE_MASK;
-
+				   I915_READ(EDP_PSR2_CTL) & ~EDP_PSR2_ENABLE);
+		else
 			I915_WRITE(EDP_PSR_CTL,
 				   I915_READ(EDP_PSR_CTL) & ~EDP_PSR_ENABLE);
-		}
-
-		/* Wait till PSR is idle */
-		if (intel_wait_for_register(dev_priv,
-					    psr_status, psr_status_mask, 0,
-					    2000))
-			DRM_ERROR("Timed out waiting for PSR Idle State\n");
-
-		dev_priv->psr.active = false;
 	} else {
 		if (dev_priv->psr.psr2_enabled)
 			WARN_ON(I915_READ(EDP_PSR2_CTL) & EDP_PSR2_ENABLE);
 		else
 			WARN_ON(I915_READ(EDP_PSR_CTL) & EDP_PSR_ENABLE);
 	}
+
+	if (dev_priv->psr.psr2_enabled) {
+		psr_status = EDP_PSR2_STATUS;
+		psr_status_mask = EDP_PSR2_STATUS_STATE_MASK;
+	} else {
+		psr_status = EDP_PSR_STATUS;
+		psr_status_mask = EDP_PSR_STATUS_STATE_MASK;
+	}
+
+	/* Wait till PSR is idle */
+	if (intel_wait_for_register(dev_priv, psr_status, psr_status_mask, 0,
+				    2000))
+		DRM_ERROR("Timed out waiting for PSR Idle State\n");
+
+	dev_priv->psr.active = false;
 }
 
 static void intel_psr_disable_locked(struct intel_dp *intel_dp)
-- 
2.19.0