drm/i915/uc: Explicitly sanitize GuC/HuC on failure and finish

Explicitly sanitize GuC/HuC on load failure and when we finish
using them to make sure our fw state tracking is always correct.

While around, use new helper in uc_reset_prepare.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190522193203.23932-6-michal.wajdeczko@intel.com

drivers/gpu/drm/i915/intel_uc.c

@@ -337,14 +337,11 @@ void intel_uc_fini(struct drm_i915_private *i915)
 	intel_guc_fini(guc);
 }
 
-void intel_uc_sanitize(struct drm_i915_private *i915)
+static void __uc_sanitize(struct drm_i915_private *i915)
 {
 	struct intel_guc *guc = &i915->guc;
 	struct intel_huc *huc = &i915->huc;
 
-	if (!USES_GUC(i915))
-		return;
-
 	GEM_BUG_ON(!HAS_GUC(i915));
 
 	intel_huc_sanitize(huc);
@@ -353,6 +350,14 @@ void intel_uc_sanitize(struct drm_i915_private *i915)
 	__intel_uc_reset_hw(i915);
 }
 
+void intel_uc_sanitize(struct drm_i915_private *i915)
+{
+	if (!USES_GUC(i915))
+		return;
+
+	__uc_sanitize(i915);
+}
+
 int intel_uc_init_hw(struct drm_i915_private *i915)
 {
 	struct intel_guc *guc = &i915->guc;
@@ -438,6 +443,8 @@ int intel_uc_init_hw(struct drm_i915_private *i915)
 err_log_capture:
 	guc_capture_load_err_log(guc);
 err_out:
+	__uc_sanitize(i915);
+
 	/*
 	 * Note that there is no fallback as either user explicitly asked for
 	 * the GuC or driver default option was to run with the GuC enabled.
@@ -462,6 +469,7 @@ void intel_uc_fini_hw(struct drm_i915_private *i915)
 		intel_guc_submission_disable(guc);
 
 	guc_disable_communication(guc);
+	__uc_sanitize(i915);
 }
 
 /**
@@ -478,7 +486,7 @@ void intel_uc_reset_prepare(struct drm_i915_private *i915)
 		return;
 
 	guc_disable_communication(guc);
-	intel_uc_sanitize(i915);
+	__uc_sanitize(i915);
 }
 
 void intel_uc_runtime_suspend(struct drm_i915_private *i915)