[Intel-gfx] [PATCH v5 3/7] drm/i915/guc: Update GuC suspend functionality in intel_uc_suspend path

[Sagar Arun Kamble]

With this patch we disable GuC submission in i915_drm_suspend. This will
destroy the client which will be setup back again. We also reuse the
complete sanitization done via intel_uc_runtime_suspend in this path.
Post drm resume this state is recreated by intel_uc_init_hw hence we need
not have similar reuse for intel_uc_resume.
This also fixes issue where intel_uc_fini_hw was being called after GPU
reset happening in i915_gem_suspend in i915_driver_unload.

v2: Rebase w.r.t removal of GuC code restructuring. Added struct_mutex
protection for i915_guc_submission_disable.

v3: Rebase w.r.t updated GuC suspend function name.

v4: Added lockdep assert in i915_guc_submission_enable/disable. Refined
intel_uc_suspend to remove unnecessary locals and simplify return.
(Michal Winiarski)

Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
Cc: Michał Winiarski <michal.winiarski at intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski at intel.com>
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble at intel.com>
---
 drivers/gpu/drm/i915/i915_guc_submission.c | 12 ++++++++++++
 drivers/gpu/drm/i915/intel_uc.c            | 11 +++++++----
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index cd5ef8b..0638ac5 100644
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -1148,6 +1148,12 @@ int i915_guc_submission_enable(struct drm_i915_private *dev_priv)
 		     sizeof(struct guc_wq_item) *
 		     I915_NUM_ENGINES > GUC_WQ_SIZE);
 
+	/*
+	 * Assert that drm.struct_mutex is held.
+	 * Needed for GuC client vma binding.
+	 */
+	lockdep_assert_held(&dev_priv->drm.struct_mutex);
+
 	if (!client) {
 		client = guc_client_alloc(dev_priv,
 					  INTEL_INFO(dev_priv)->ring_mask,
@@ -1197,6 +1203,12 @@ void i915_guc_submission_disable(struct drm_i915_private *dev_priv)
 {
 	struct intel_guc *guc = &dev_priv->guc;
 
+	/*
+	 * Assert that drm.struct_mutex is held.
+	 * Needed for GuC client vma unbinding.
+	 */
+	lockdep_assert_held(&dev_priv->drm.struct_mutex);
+
 	guc_interrupts_release(dev_priv);
 
 	/* Revert back to manual ELSP submission */
diff --git a/drivers/gpu/drm/i915/intel_uc.c b/drivers/gpu/drm/i915/intel_uc.c
index 66d2cff..0e971d7 100644
--- a/drivers/gpu/drm/i915/intel_uc.c
+++ b/drivers/gpu/drm/i915/intel_uc.c
@@ -446,9 +446,6 @@ void intel_uc_fini_hw(struct drm_i915_private *dev_priv)
 	if (!i915.enable_guc_loading)
 		return;
 
-	if (i915.enable_guc_submission)
-		i915_guc_submission_disable(dev_priv);
-
 	guc_disable_communication(&dev_priv->guc);
 
 	if (i915.enable_guc_submission) {
@@ -585,7 +582,13 @@ int intel_uc_runtime_resume(struct drm_i915_private *dev_priv)
 
 int intel_uc_suspend(struct drm_i915_private *dev_priv)
 {
-	return intel_guc_suspend(dev_priv);
+	if (i915.enable_guc_submission) {
+		mutex_lock(&dev_priv->drm.struct_mutex);
+		i915_guc_submission_disable(dev_priv);
+		mutex_unlock(&dev_priv->drm.struct_mutex);
+	}
+
+	return intel_uc_runtime_suspend(dev_priv);
 }
 
 int intel_uc_resume(struct drm_i915_private *dev_priv)
-- 
1.9.1