drm/i915/selftests: Add initial GuC selftest for scrubbing lost G2H

While debugging an issue with full GT resets I went down a rabbit hole
thinking the scrubbing of lost G2H wasn't working correctly. This proved
to be incorrect as this was working just fine but this chase inspired me
to write a selftest to prove that this works. This simple selftest
injects errors dropping various G2H and then issues a full GT reset
proving that the scrubbing of these G2H doesn't blow up.

v2:
 (Daniel Vetter)
  - Use ifdef instead of macros for selftests
v3:
 (Checkpatch)
  - A space after 'switch' statement
v4:
 (Daniele)
  - A comment saying GT won't idle if G2H are lost

Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-12-matthew.brost@intel.com

1 files changed, 18 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h
index e54351a170e2..3a73f3117873 100644
--- a/drivers/gpu/drm/i915/gt/intel_context_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_context_types.h
@@ -198,6 +198,24 @@ struct intel_context {
 	 */
 	u8 guc_prio;
 	u32 guc_prio_count[GUC_CLIENT_PRIORITY_NUM];
+
+#ifdef CONFIG_DRM_I915_SELFTEST
+	/**
+	 * @drop_schedule_enable: Force drop of schedule enable G2H for selftest
+	 */
+	bool drop_schedule_enable;
+
+	/**
+	 * @drop_schedule_disable: Force drop of schedule disable G2H for
+	 * selftest
+	 */
+	bool drop_schedule_disable;
+
+	/**
+	 * @drop_deregister: Force drop of deregister G2H for selftest
+	 */
+	bool drop_deregister;
+#endif
 };
 
 #endif /* __INTEL_CONTEXT_TYPES__ */