diff --git a/arch/s390/lib/delay.c b/arch/s390/lib/delay.c
index 7f17555..d4aa107 100644
--- a/arch/s390/lib/delay.c
+++ b/arch/s390/lib/delay.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *    Precise Delay Loops for S390
  *