[Intel-gfx] [PATCH v2 2/2] drm/i915/huc: Adjust HuC state accordingly after GuC fetch error

[Michał Winiarski]

From: Michał Winiarski <michal.winiarski at intel.com>

Firmware "Selected" state is a transient state - we don't expect to see
it after finishing driver probe, we even have asserts sprinkled over
i915 to confirm whether that's the case.
Unfortunately - we don't handle the transition out of "Selected" in case
of GuC fetch error, leading those asserts to fire when calling
"intel_huc_is_used()".

v2: Add dbg print when moving HuC into error state (Daniele)

Reported-by: Marcin Bernatowicz <marcin.bernatowicz at intel.com>
Signed-off-by: Michał Winiarski <michal.winiarski at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
Cc: Marcin Bernatowicz <marcin.bernatowicz at intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
---
 drivers/gpu/drm/i915/gt/uc/intel_uc.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc.c b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
index 1c2d6358826c..d6f55f70889d 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_uc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
@@ -267,8 +267,17 @@ static void __uc_fetch_firmwares(struct intel_uc *uc)
 	GEM_BUG_ON(!intel_uc_wants_guc(uc));
 
 	err = intel_uc_fw_fetch(&uc->guc.fw);
-	if (err)
+	if (err) {
+		/* Make sure we transition out of transient "SELECTED" state */
+		if (intel_uc_wants_huc(uc)) {
+			drm_dbg(&uc_to_gt(uc)->i915->drm,
+				"Failed to fetch GuC: %d disabling HuC\n", err);
+			intel_uc_fw_change_status(&uc->huc.fw,
+						  INTEL_UC_FIRMWARE_ERROR);
+		}
+
 		return;
+	}
 
 	if (intel_uc_wants_huc(uc))
 		intel_uc_fw_fetch(&uc->huc.fw);
-- 
2.27.0