[Intel-gfx] [PATCH 3/4] drm/i915/psr: Provide block functionality for RPM.

[Rodrigo Vivi]

This patch gives RPM the hability to block PSR whenever needed.

It is in a separated patch because besides the credits the RPM
part is still uncertaing at this time.

This blocker logic was heavily copied from Dhinakaran's patch
[3/3] drm/i915/psr: Do not activate PSR when vblank interrupts are
 enabled

Credits-to: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h  |  1 +
 drivers/gpu/drm/i915/intel_drv.h |  2 ++
 drivers/gpu/drm/i915/intel_psr.c | 43 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 46 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 65ada5d..4892972 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1020,6 +1020,7 @@ struct i915_psr {
 	bool active;
 	struct delayed_work work;
 	unsigned busy_frontbuffer_bits;
+	bool rpm_block;
 	bool psr2_support;
 	bool aux_frame_sync;
 	bool link_standby;
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 102c858..d26c3fb 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1567,6 +1567,8 @@ void intel_psr_flush(struct drm_i915_private *dev_priv,
 		     unsigned frontbuffer_bits,
 		     enum fb_op_origin origin);
 void intel_psr_init(struct drm_i915_private *dev_priv);
+void intel_psr_rpm_block(struct drm_i915_private *dev_priv);
+void intel_psr_rpm_unblock(struct drm_i915_private *dev_priv);
 void intel_psr_single_frame_update(struct drm_i915_private *dev_priv,
 				   unsigned frontbuffer_bits);
 
diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
index 24e282b..2be94ef 100644
--- a/drivers/gpu/drm/i915/intel_psr.c
+++ b/drivers/gpu/drm/i915/intel_psr.c
@@ -660,6 +660,49 @@ static void intel_psr_exit(struct drm_i915_private *dev_priv)
 }
 
 /**
+ * intel_psr_rpm_block - PSR blocker for Runtime PM.
+ * @dev_priv: DRM i915 private device
+ *
+ * This function provides a psr blocker scheme for runtime PM.
+ * In case runtime PM domains need to block PSR for any reason
+ * this function needs to be called.
+ * It will immediately force PSR exit and prevent PSR to get activated.
+ */
+void intel_psr_rpm_block(struct drm_i915_private *dev_priv)
+{
+	mutex_lock(&dev_priv->psr.lock);
+	if (!dev_priv->psr.enabled)
+		goto unlock;
+
+	dev_priv->psr.rpm_block = true;
+
+	if (dev_priv->psr.active)
+		intel_psr_exit(dev_priv);
+unlock:
+	mutex_unlock(&dev_priv->psr.lock);
+}
+
+/**
+ * intel_psr_rpm_unblock - PSR unblocker for Runtime PM.
+ * @dev_priv: DRM i915 private device
+ *
+ * This function unblock PSR. Should only be called by RPM
+ * after the domain in question had blocked PSR but now is being put.
+ */
+void intel_psr_rpm_unblock(struct drm_i915_private *dev_priv)
+{
+	mutex_lock(&dev_priv->psr.lock);
+	if (!dev_priv->psr.enabled)
+		goto unlock;
+
+	dev_priv->psr.rpm_block = false;
+
+	schedule_delayed_work(&dev_priv->psr.work, msecs_to_jiffies(100));
+unlock:
+	mutex_unlock(&dev_priv->psr.lock);
+}
+
+/**
  * intel_psr_single_frame_update - Single Frame Update
  * @dev_priv: DRM i915 private device
  * @frontbuffer_bits: frontbuffer plane tracking bits
-- 
2.4.3