[Intel-gfx] [PATCH 2/2] drm/i915: make crtc enable/disable asynchronous

[Jesse Barnes]

The intent is to get back to userspace as quickly as possible so it can
start doing drawing or whatever.  It should also allow our
suspend/resume/init time to improve a lot.
---
 drivers/gpu/drm/i915/i915_irq.c      | 10 +++++++++-
 drivers/gpu/drm/i915/intel_display.c | 27 ++++++++++++++++++++-------
 drivers/gpu/drm/i915/intel_drv.h     |  4 ++++
 3 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 74918e7..9490d32 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -897,8 +897,16 @@ static void i915_hotplug_work_func(struct work_struct *work)
 		intel_connector = to_intel_connector(connector);
 		intel_encoder = intel_connector->encoder;
 		if (hpd_event_bits & (1 << intel_encoder->hpd_pin)) {
-			if (intel_encoder->hot_plug)
+			if (intel_encoder->hot_plug) {
+				struct drm_crtc *crtc =
+					intel_encoder->base.crtc;
+				if (crtc) {
+					mutex_lock(&crtc->mutex);
+					intel_sync_crtc(intel_encoder->base.crtc);
+					mutex_unlock(&crtc->mutex);
+				}
 				intel_encoder->hot_plug(intel_encoder);
+			}
 			if (intel_hpd_irq_event(dev, connector))
 				changed = true;
 		}
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 006ec10..302aae1 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1729,6 +1729,11 @@ static void intel_crtc_disable_work(struct work_struct *work)
 {
 	struct intel_crtc *intel_crtc = container_of(work, struct intel_crtc,
 						     disable_work);
+	struct drm_i915_private *dev_priv = intel_crtc->base.dev->dev_private;
+
+	mutex_lock(&intel_crtc->base.mutex);
+	dev_priv->display._crtc_disable(&intel_crtc->base);
+	mutex_unlock(&intel_crtc->base.mutex);
 }
 
 void intel_queue_crtc_disable(struct drm_crtc *crtc)
@@ -1744,6 +1749,11 @@ static void intel_crtc_enable_work(struct work_struct *work)
 {
 	struct intel_crtc *intel_crtc = container_of(work, struct intel_crtc,
 						     enable_work);
+	struct drm_i915_private *dev_priv = intel_crtc->base.dev->dev_private;
+
+	mutex_lock(&intel_crtc->base.mutex);
+	dev_priv->display._crtc_enable(&intel_crtc->base);
+	mutex_unlock(&intel_crtc->base.mutex);
 }
 
 static void intel_queue_crtc_enable(struct drm_crtc *crtc)
@@ -1755,14 +1765,16 @@ static void intel_queue_crtc_enable(struct drm_crtc *crtc)
 	queue_work(dev_priv->wq, &intel_crtc->enable_work);
 }
 
-static void intel_sync_crtc(struct drm_crtc *crtc)
+void intel_sync_crtc(struct drm_crtc *crtc)
 {
-	struct drm_device *dev = crtc->dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
 
+	WARN(!mutex_is_locked(&intel_crtc->base.mutex), "need crtc mutex\n");
+
+	mutex_unlock(&intel_crtc->base.mutex);
 	flush_work(&intel_crtc->disable_work);
 	flush_work(&intel_crtc->enable_work);
+	mutex_lock(&intel_crtc->base.mutex);
 }
 
 /**
@@ -9723,8 +9735,9 @@ static int intel_set_mode(struct drm_crtc *crtc,
 
 	ret = __intel_set_mode(crtc, mode, x, y, fb);
 
-	if (ret == 0)
-		intel_modeset_check_state(crtc->dev);
+	/* FIXME: need to check after the CRTC changes have been applied */
+//	if (ret == 0)
+//		intel_modeset_check_state(crtc->dev);
 
 	return ret;
 }
@@ -10194,8 +10207,8 @@ static void intel_crtc_init(struct drm_device *dev, int pipe)
 
 	drm_crtc_helper_add(&intel_crtc->base, &intel_helper_funcs);
 
-	INIT_WORK(intel_crtc->enable_work, intel_crtc_enable_work);
-	INIT_WORK(intel_crtc->disable_work, intel_crtc_disable_work);
+	INIT_WORK(&intel_crtc->enable_work, intel_crtc_enable_work);
+	INIT_WORK(&intel_crtc->disable_work, intel_crtc_disable_work);
 }
 
 enum pipe intel_get_pipe_from_connector(struct intel_connector *connector)
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index bfae2ef..b187c51 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -373,6 +373,9 @@ struct intel_crtc {
 		/* watermarks currently being used  */
 		struct intel_pipe_wm active;
 	} wm;
+
+	struct work_struct enable_work;
+	struct work_struct disable_work;
 };
 
 struct intel_plane_wm_parameters {
@@ -708,6 +711,7 @@ void hsw_disable_ips(struct intel_crtc *crtc);
 void intel_display_set_init_power(struct drm_device *dev, bool enable);
 int valleyview_get_vco(struct drm_i915_private *dev_priv);
 void intel_queue_crtc_disable(struct drm_crtc *crtc);
+void intel_sync_crtc(struct drm_crtc *crtc);
 
 /* intel_dp.c */
 void intel_dp_init(struct drm_device *dev, int output_reg, enum port port);
-- 
1.8.4.2