diff --git a/lib/locks/exclusive/aarch64/spinlock.S b/lib/locks/exclusive/aarch64/spinlock.S
index e2f9eaa..d0569f1 100644
--- a/lib/locks/exclusive/aarch64/spinlock.S
+++ b/lib/locks/exclusive/aarch64/spinlock.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -39,8 +39,6 @@
 
 #if USE_CAS
 
-	.arch	armv8.1-a
-
 /*
  * Acquire lock using Compare and Swap instruction.
  *
@@ -60,8 +58,6 @@
 	ret
 endfunc spin_lock
 
-	.arch	armv8-a
-
 #else /* !USE_CAS */
 
 /*