drm/xe/guc: Don't treat GuC generic CAT error as protocol error

GuC uses GUC_ID_UNKNOWN if it can not map the CAT fault to any
context. We shouldn't treat that as G2H protocol error that would
justify a GT reset, as it may happen due to some VF activity.

Signed-off-by: Michal Wajdeczko <[e-mail]>
Cc: Matthew Brost <[e-mail]>
Reviewed-by: Matthew Brost <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/xe/xe_guc_fwif.h

···
 #define G2H_LEN_DW_TLB_INVALIDATE		3
 
 #define GUC_ID_MAX			65535
+#define GUC_ID_UNKNOWN			0xffffffff
 
 #define GUC_CONTEXT_DISABLE		0
 #define GUC_CONTEXT_ENABLE		1

drivers/gpu/drm/xe/xe_guc_submit.c

···
 
 	guc_id = msg[0];
 
+	if (guc_id == GUC_ID_UNKNOWN) {
+		/*
+		 * GuC uses GUC_ID_UNKNOWN if it can not map the CAT fault to any PF/VF
+		 * context. In such case only PF will be notified about that fault.
+		 */
+		xe_gt_err_ratelimited(gt, "Memory CAT error reported by GuC!\n");
+		return 0;
+	}
+
 	q = g2h_exec_queue_lookup(guc, guc_id);
 	if (unlikely(!q))
 		return -EPROTO;