[PATCH 15/22] drm/i915/guc: Update GuC ggtt.invalidate/interrupts/communication across RPM suspend/resume

[Sagar Arun Kamble]

Apart from configuring interrupts, we need to update the ggtt invalidate
interface and GuC communication on suspend/resume. This functionality
can be reused for other suspend and reset paths.

v2: Rebase w.r.t removal of GuC code restructuring.

v3: Removed GuC specific helpers as tasks other than send H2G for
sleep/resume are to be done from uc generic functions. (Michal Wajdeczko)

v4: Simplified/Unified the error messaging in uc_runtime_suspend/resume.
(Michal Wajdeczko). Rebase w.r.t i915_modparams change.
Added documentation to intel_uc_runtime_suspend/resume.

v5: Removed enable_guc_loading based check from intel_uc_runtime_suspend
and intel_uc_runtime_resume and pulled FW load_status based checks from
intel_guc_suspend/resume into these functions. (Michal Wajdeczko)

v6: Adjusted intel_uc_runtime_resume with prototype change to not return
value.

v7: Rebase.

Signed-off-by: Sagar Arun Kamble <sagar.a.kamble at intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
Cc: Michał Winiarski <michal.winiarski at intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
---
 drivers/gpu/drm/i915/intel_guc.c | 11 ---------
 drivers/gpu/drm/i915/intel_uc.c  | 50 ++++++++++++++++++++++++++++++++++++++--
 2 files changed, 48 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_guc.c b/drivers/gpu/drm/i915/intel_guc.c
index 0d095a2..150ed5c 100644
--- a/drivers/gpu/drm/i915/intel_guc.c
+++ b/drivers/gpu/drm/i915/intel_guc.c
@@ -177,11 +177,6 @@ int intel_guc_suspend(struct drm_i915_private *dev_priv)
 	struct i915_gem_context *ctx;
 	u32 data[3];
 
-	if (guc->fw.load_status != INTEL_UC_FIRMWARE_SUCCESS)
-		return 0;
-
-	gen9_disable_guc_interrupts(dev_priv);
-
 	ctx = dev_priv->kernel_context;
 
 	data[0] = INTEL_GUC_ACTION_ENTER_S_STATE;
@@ -204,12 +199,6 @@ int intel_guc_resume(struct drm_i915_private *dev_priv)
 	struct i915_gem_context *ctx;
 	u32 data[3];
 
-	if (guc->fw.load_status != INTEL_UC_FIRMWARE_SUCCESS)
-		return 0;
-
-	if (i915_modparams.guc_log_level >= 0)
-		gen9_enable_guc_interrupts(dev_priv);
-
 	ctx = dev_priv->kernel_context;
 
 	data[0] = INTEL_GUC_ACTION_EXIT_S_STATE;
diff --git a/drivers/gpu/drm/i915/intel_uc.c b/drivers/gpu/drm/i915/intel_uc.c
index a99ec3b..d8d5d5a 100644
--- a/drivers/gpu/drm/i915/intel_uc.c
+++ b/drivers/gpu/drm/i915/intel_uc.c
@@ -297,20 +297,66 @@ void intel_uc_sanitize(struct drm_i915_private *dev_priv,
 	intel_guc_sanitize(dev_priv, engine_mask);
 }
 
+/**
+ * intel_uc_runtime_suspend() - Suspend uC operation.
+ * @dev_priv: i915 device private
+ *
+ * This function invokes GuC OS suspension, makes ggtt_invalidate function to
+ * point to non-GuC variant, disables GuC interrupts and disable communication
+ * with GuC.
+ *
+ * Return:	non-zero code on error
+ */
 int intel_uc_runtime_suspend(struct drm_i915_private *dev_priv)
 {
 	int ret;
 
+	if (dev_priv->guc.fw.load_status != INTEL_UC_FIRMWARE_SUCCESS)
+		return 0;
+
 	ret = intel_guc_suspend(dev_priv);
 	if (ret)
-		DRM_ERROR("Failed to suspend GuC\n");
+		goto out;
+
+	i915_ggtt_disable_guc(dev_priv);
+	gen9_disable_guc_interrupts(dev_priv);
+	guc_disable_communication(&dev_priv->guc);
+
+out:
+	if (ret)
+		DRM_ERROR("uC runtime suspend failed (%d)\n", ret);
 
 	return ret;
 }
 
+/**
+ * intel_uc_runtime_resume() - Resume uC operation.
+ * @dev_priv: i915 device private
+ *
+ * This function enables communication with GuC, enables GuC interrupts,
+ * makes ggtt_invalidate function to point to GuC variant and invokes
+ * GuC OS resumption.
+ */
 void intel_uc_runtime_resume(struct drm_i915_private *dev_priv)
 {
-	intel_guc_resume(dev_priv);
+	int err;
+
+	if (dev_priv->guc.fw.load_status != INTEL_UC_FIRMWARE_SUCCESS)
+		return;
+
+	err = guc_enable_communication(&dev_priv->guc);
+	if (err)
+		goto out;
+
+	if (i915_modparams.guc_log_level >= 0)
+		gen9_enable_guc_interrupts(dev_priv);
+	i915_ggtt_enable_guc(dev_priv);
+
+	err = intel_guc_resume(dev_priv);
+
+out:
+	if (err)
+		DRM_ERROR("uC runtime resume failed (%d)\n", err);
 }
 
 void intel_uc_suspend(struct drm_i915_private *dev_priv)
-- 
1.9.1