[PATCH] drm/xe/guc: Treat non-response message after BUSY as unexpected

[Michal Wajdeczko]

Once GuC replied with GUC_HXG_TYPE_NO_RESPONSE_BUSY message then
we may expect that only RESPONSE_SUCCESS or FAILURE message will
be sent, anything else is a violation of the HXG protocol.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
Cc: Matthew Brost <matthew.brost at intel.com>
---
 drivers/gpu/drm/xe/xe_guc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_guc.c b/drivers/gpu/drm/xe/xe_guc.c
index 6e73ebf67251..254c9d3c8c73 100644
--- a/drivers/gpu/drm/xe/xe_guc.c
+++ b/drivers/gpu/drm/xe/xe_guc.c
@@ -718,8 +718,12 @@ int xe_guc_mmio_send_recv(struct xe_guc *guc, const u32 *request,
 		if (unlikely(FIELD_GET(GUC_HXG_MSG_0_ORIGIN, header) !=
 			     GUC_HXG_ORIGIN_GUC))
 			goto proto;
-		if (unlikely(ret))
+		if (unlikely(ret)) {
+			if (FIELD_GET(GUC_HXG_MSG_0_TYPE, header) !=
+			    GUC_HXG_TYPE_NO_RESPONSE_BUSY)
+				goto proto;
 			goto timeout;
+		}
 	}
 
 	if (FIELD_GET(GUC_HXG_MSG_0_TYPE, header) ==

base-commit: 79184e72263e91528195db01783148435c7e4fad
-- 
2.25.1