[PATCH 06/12] drm/xe: Do not forward invalid TLB invalidation seqnos to upper layers

[Matthew Brost <matthew.brost@intel.com>]

Context-based TLB invalidations send multiple H2G messages per seqno,
with only the final H2G containing a valid seqno — the others carry an
invalid seqno. The G2H handler drops these invalid seqnos to avoid
prematurely signaling a TLB invalidation fence.

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
 drivers/gpu/drm/xe/xe_guc_tlb_inval.c   | 3 ++-
 drivers/gpu/drm/xe/xe_tlb_inval_types.h | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_guc_tlb_inval.c b/drivers/gpu/drm/xe/xe_guc_tlb_inval.c
index 61bfa0d485f6..995789f0d31f 100644
--- a/drivers/gpu/drm/xe/xe_guc_tlb_inval.c
+++ b/drivers/gpu/drm/xe/xe_guc_tlb_inval.c
@@ -235,7 +235,8 @@ int xe_guc_tlb_inval_done_handler(struct xe_guc *guc, u32 *msg, u32 len)
 	if (unlikely(len != 1))
 		return -EPROTO;
 
-	xe_tlb_inval_done_handler(&gt->tlb_inval, msg[0]);
+	if (msg[0] != TLB_INVALIDATION_SEQNO_INVALID)
+		xe_tlb_inval_done_handler(&gt->tlb_inval, msg[0]);
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/xe/xe_tlb_inval_types.h b/drivers/gpu/drm/xe/xe_tlb_inval_types.h
index 8f8b060e9005..7a6967ce3b76 100644
--- a/drivers/gpu/drm/xe/xe_tlb_inval_types.h
+++ b/drivers/gpu/drm/xe/xe_tlb_inval_types.h
@@ -80,6 +80,7 @@ struct xe_tlb_inval {
 	const struct xe_tlb_inval_ops *ops;
 	/** @tlb_inval.seqno: TLB invalidation seqno, protected by CT lock */
 #define TLB_INVALIDATION_SEQNO_MAX	0x100000
+#define TLB_INVALIDATION_SEQNO_INVALID	TLB_INVALIDATION_SEQNO_MAX
 	int seqno;
 	/** @tlb_invalidation.seqno_lock: protects @tlb_invalidation.seqno */
 	struct mutex seqno_lock;
-- 
2.34.1