drm/msm/sde: move power resource handling for vblank to crtcs

Move the power resource request/release from the sde kms layer
into the CRTCs so that proper accounting for suspend/resume
operations may be done. A single power resource request is
made as long while the CRTC's vblank request ref count is not
zero and the driver is not in a suspended state.

CRs-Fixed: 2019307
Change-Id: I2d47567ec3dded72faed8bd5441d8d4653d5ef25
Signed-off-by: Clarence Ip <cip@codeaurora.org>

4 files changed, 153 insertions, 39 deletions

diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index fd3498ba43ab..5597e42a7c92 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -417,6 +417,15 @@ void __msm_fence_worker(struct work_struct *work);
 		(_cb)->func = _func;                         \
 	} while (0)
 
+static inline bool msm_is_suspend_state(struct drm_device *dev)
+{
+	if (!dev || !dev->dev_private)
+		return false;
+
+	return ((struct msm_drm_private *)dev->dev_private)->suspend_state !=
+		NULL;
+}
+
 int msm_atomic_commit(struct drm_device *dev,
 		struct drm_atomic_state *state, bool async);
 
diff --git a/drivers/gpu/drm/msm/sde/sde_crtc.c b/drivers/gpu/drm/msm/sde/sde_crtc.c
index 5323c0194594..4110f8c915b8 100644
--- a/drivers/gpu/drm/msm/sde/sde_crtc.c
+++ b/drivers/gpu/drm/msm/sde/sde_crtc.c
@@ -57,7 +57,17 @@
 
 static inline struct sde_kms *_sde_crtc_get_kms(struct drm_crtc *crtc)
 {
-	struct msm_drm_private *priv = crtc->dev->dev_private;
+	struct msm_drm_private *priv;
+
+	if (!crtc || !crtc->dev || !crtc->dev->dev_private) {
+		SDE_ERROR("invalid crtc\n");
+		return NULL;
+	}
+	priv = crtc->dev->dev_private;
+	if (!priv || !priv->kms) {
+		SDE_ERROR("invalid kms\n");
+		return NULL;
+	}
 
 	return to_sde_kms(priv->kms);
 }
@@ -77,10 +87,10 @@ static void sde_crtc_destroy(struct drm_crtc *crtc)
 	sde_cp_crtc_destroy_properties(crtc);
 
 	debugfs_remove_recursive(sde_crtc->debugfs_root);
-	mutex_destroy(&sde_crtc->crtc_lock);
 	sde_fence_deinit(&sde_crtc->output_fence);
 
 	drm_crtc_cleanup(crtc);
+	mutex_destroy(&sde_crtc->crtc_lock);
 	kfree(sde_crtc);
 }
 
@@ -941,6 +951,104 @@ end:
 }
 
 /**
+ * _sde_crtc_vblank_enable_nolock - update power resource and vblank request
+ * @sde_crtc: Pointer to sde crtc structure
+ * @enable: Whether to enable/disable vblanks
+ */
+static void _sde_crtc_vblank_enable_nolock(
+		struct sde_crtc *sde_crtc, bool enable)
+{
+	struct drm_device *dev;
+	struct drm_crtc *crtc;
+	struct drm_encoder *enc;
+	struct msm_drm_private *priv;
+	struct sde_kms *sde_kms;
+
+	if (!sde_crtc) {
+		SDE_ERROR("invalid crtc\n");
+		return;
+	}
+
+	crtc = &sde_crtc->base;
+	dev = crtc->dev;
+	priv = dev->dev_private;
+
+	if (!priv->kms) {
+		SDE_ERROR("invalid kms\n");
+		return;
+	}
+	sde_kms = to_sde_kms(priv->kms);
+
+	if (enable) {
+		sde_power_resource_enable(&priv->phandle,
+				sde_kms->core_client, true);
+		list_for_each_entry(enc, &dev->mode_config.encoder_list, head) {
+			if (enc->crtc != crtc)
+				continue;
+
+			SDE_EVT32(DRMID(crtc), DRMID(enc), enable);
+
+			sde_encoder_register_vblank_callback(enc,
+					sde_crtc_vblank_cb, (void *)crtc);
+		}
+	} else {
+		list_for_each_entry(enc, &dev->mode_config.encoder_list, head) {
+			if (enc->crtc != crtc)
+				continue;
+
+			SDE_EVT32(DRMID(crtc), DRMID(enc), enable);
+
+			sde_encoder_register_vblank_callback(enc, NULL, NULL);
+		}
+		sde_power_resource_enable(&priv->phandle,
+				sde_kms->core_client, false);
+	}
+}
+
+/**
+ * _sde_crtc_set_suspend - notify crtc of suspend enable/disable
+ * @crtc: Pointer to drm crtc object
+ * @enable: true to enable suspend, false to indicate resume
+ */
+static void _sde_crtc_set_suspend(struct drm_crtc *crtc, bool enable)
+{
+	struct sde_crtc *sde_crtc;
+	struct msm_drm_private *priv;
+	struct sde_kms *sde_kms;
+
+	if (!crtc || !crtc->dev || !crtc->dev->dev_private) {
+		SDE_ERROR("invalid crtc\n");
+		return;
+	}
+	sde_crtc = to_sde_crtc(crtc);
+	priv = crtc->dev->dev_private;
+
+	if (!priv->kms) {
+		SDE_ERROR("invalid crtc kms\n");
+		return;
+	}
+	sde_kms = to_sde_kms(priv->kms);
+
+	SDE_DEBUG("crtc%d suspend = %d\n", crtc->base.id, enable);
+
+	mutex_lock(&sde_crtc->crtc_lock);
+
+	/*
+	 * If the vblank refcount != 0, release a power reference on suspend
+	 * and take it back during resume (if it is still != 0).
+	 */
+	if (sde_crtc->suspend == enable)
+		SDE_DEBUG("crtc%d suspend already set to %d, ignoring update\n",
+				crtc->base.id, enable);
+	else if (atomic_read(&sde_crtc->vblank_refcount) != 0)
+		_sde_crtc_vblank_enable_nolock(sde_crtc, !enable);
+
+	sde_crtc->suspend = enable;
+
+	mutex_unlock(&sde_crtc->crtc_lock);
+}
+
+/**
  * sde_crtc_duplicate_state - state duplicate hook
  * @crtc: Pointer to drm crtc structure
  * @Returns: Pointer to new drm_crtc_state structure
@@ -990,6 +1098,10 @@ static void sde_crtc_reset(struct drm_crtc *crtc)
 		return;
 	}
 
+	/* revert suspend actions, if necessary */
+	if (msm_is_suspend_state(crtc->dev))
+		_sde_crtc_set_suspend(crtc, false);
+
 	/* remove previous state, if present */
 	if (crtc->state) {
 		sde_crtc_destroy_state(crtc, crtc->state);
@@ -1015,25 +1127,32 @@ static void sde_crtc_reset(struct drm_crtc *crtc)
 
 static void sde_crtc_disable(struct drm_crtc *crtc)
 {
-	struct msm_drm_private *priv;
-	struct sde_crtc *sde_crtc;
 	struct drm_encoder *encoder;
+	struct sde_crtc *sde_crtc;
 	struct sde_kms *sde_kms;
+	struct msm_drm_private *priv;
 
-	if (!crtc) {
+	if (!crtc || !crtc->dev || !crtc->state) {
 		SDE_ERROR("invalid crtc\n");
 		return;
 	}
 	sde_crtc = to_sde_crtc(crtc);
 	sde_kms = _sde_crtc_get_kms(crtc);
+	if (!sde_kms || !sde_kms->dev || !sde_kms->dev->dev_private) {
+		SDE_ERROR("invalid kms handle\n");
+		return;
+	}
 	priv = sde_kms->dev->dev_private;
 
 	SDE_DEBUG("crtc%d\n", crtc->base.id);
 
+	if (msm_is_suspend_state(crtc->dev))
+		_sde_crtc_set_suspend(crtc, true);
+
 	mutex_lock(&sde_crtc->crtc_lock);
 	SDE_EVT32(DRMID(crtc));
 
-	if (atomic_read(&sde_crtc->vblank_refcount)) {
+	if (atomic_read(&sde_crtc->vblank_refcount) && !sde_crtc->suspend) {
 		SDE_ERROR("crtc%d invalid vblank refcount\n",
 				crtc->base.id);
 		SDE_EVT32(DRMID(crtc));
@@ -1262,40 +1381,36 @@ end:
 
 int sde_crtc_vblank(struct drm_crtc *crtc, bool en)
 {
-	struct sde_crtc *sde_crtc = to_sde_crtc(crtc);
-	struct drm_encoder *encoder;
-	struct drm_device *dev = crtc->dev;
+	struct sde_crtc *sde_crtc;
+	int rc = 0;
+
+	if (!crtc) {
+		SDE_ERROR("invalid crtc\n");
+		return -EINVAL;
+	}
+	sde_crtc = to_sde_crtc(crtc);
 
+	mutex_lock(&sde_crtc->crtc_lock);
 	if (en && atomic_inc_return(&sde_crtc->vblank_refcount) == 1) {
 		SDE_DEBUG("crtc%d vblank enable\n", crtc->base.id);
+		if (!sde_crtc->suspend)
+			_sde_crtc_vblank_enable_nolock(sde_crtc, true);
 	} else if (!en && atomic_read(&sde_crtc->vblank_refcount) < 1) {
 		SDE_ERROR("crtc%d invalid vblank disable\n", crtc->base.id);
-		return -EINVAL;
+		rc = -EINVAL;
 	} else if (!en && atomic_dec_return(&sde_crtc->vblank_refcount) == 0) {
 		SDE_DEBUG("crtc%d vblank disable\n", crtc->base.id);
+		if (!sde_crtc->suspend)
+			_sde_crtc_vblank_enable_nolock(sde_crtc, false);
 	} else {
 		SDE_DEBUG("crtc%d vblank %s refcount:%d\n",
 				crtc->base.id,
 				en ? "enable" : "disable",
 				atomic_read(&sde_crtc->vblank_refcount));
-		return 0;
-	}
-
-	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
-		if (encoder->crtc != crtc)
-			continue;
-
-		SDE_EVT32(DRMID(crtc), en);
-
-		if (en)
-			sde_encoder_register_vblank_callback(encoder,
-					sde_crtc_vblank_cb, (void *)crtc);
-		else
-			sde_encoder_register_vblank_callback(encoder, NULL,
-					NULL);
 	}
 
-	return 0;
+	mutex_unlock(&sde_crtc->crtc_lock);
+	return rc;
 }
 
 void sde_crtc_cancel_pending_flip(struct drm_crtc *crtc,
@@ -1739,6 +1854,7 @@ struct drm_crtc *sde_crtc_init(struct drm_device *dev,
 	crtc->dev = dev;
 	atomic_set(&sde_crtc->vblank_refcount, 0);
 
+	mutex_init(&sde_crtc->crtc_lock);
 	spin_lock_init(&sde_crtc->spin_lock);
 	atomic_set(&sde_crtc->frame_pending, 0);
 
@@ -1760,7 +1876,6 @@ struct drm_crtc *sde_crtc_init(struct drm_device *dev,
 	snprintf(sde_crtc->name, SDE_CRTC_NAME_SIZE, "crtc%u", crtc->base.id);
 
 	/* initialize output fence support */
-	mutex_init(&sde_crtc->crtc_lock);
 	sde_fence_init(&sde_crtc->output_fence, sde_crtc->name, crtc->base.id);
 
 	/* initialize debugfs support */
diff --git a/drivers/gpu/drm/msm/sde/sde_crtc.h b/drivers/gpu/drm/msm/sde/sde_crtc.h
index aaa815c76c4e..6b8483d574b1 100644
--- a/drivers/gpu/drm/msm/sde/sde_crtc.h
+++ b/drivers/gpu/drm/msm/sde/sde_crtc.h
@@ -82,6 +82,7 @@ struct sde_crtc_frame_event {
  * @vblank_cb_count : count of vblank callback since last reset
  * @vblank_cb_time  : ktime at vblank count reset
  * @vblank_refcount : reference count for vblank enable request
+ * @suspend         : whether or not a suspend operation is in progress
  * @feature_list  : list of color processing features supported on a crtc
  * @active_list   : list of color processing features are active
  * @dirty_list    : list of color processing features are dirty
@@ -117,6 +118,7 @@ struct sde_crtc {
 	u32 vblank_cb_count;
 	ktime_t vblank_cb_time;
 	atomic_t vblank_refcount;
+	bool suspend;
 
 	struct list_head feature_list;
 	struct list_head active_list;
diff --git a/drivers/gpu/drm/msm/sde/sde_kms.c b/drivers/gpu/drm/msm/sde/sde_kms.c
index 031493aa42b8..f8e0eae557ff 100644
--- a/drivers/gpu/drm/msm/sde/sde_kms.c
+++ b/drivers/gpu/drm/msm/sde/sde_kms.c
@@ -328,24 +328,12 @@ static int sde_debugfs_danger_init(struct sde_kms *sde_kms,
 
 static int sde_kms_enable_vblank(struct msm_kms *kms, struct drm_crtc *crtc)
 {
-	struct sde_kms *sde_kms = to_sde_kms(kms);
-	struct drm_device *dev = sde_kms->dev;
-	struct msm_drm_private *priv = dev->dev_private;
-
-	sde_power_resource_enable(&priv->phandle, sde_kms->core_client, true);
-
 	return sde_crtc_vblank(crtc, true);
 }
 
 static void sde_kms_disable_vblank(struct msm_kms *kms, struct drm_crtc *crtc)
 {
-	struct sde_kms *sde_kms = to_sde_kms(kms);
-	struct drm_device *dev = sde_kms->dev;
-	struct msm_drm_private *priv = dev->dev_private;
-
 	sde_crtc_vblank(crtc, false);
-
-	sde_power_resource_enable(&priv->phandle, sde_kms->core_client, false);
 }
 
 static void sde_kms_prepare_commit(struct msm_kms *kms,