diff --git a/include/efi.h b/include/efi.h
index e1854ec..b1deb60 100644
--- a/include/efi.h
+++ b/include/efi.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Extensible Firmware Interface
  * Based on 'Extensible Firmware Interface Specification' version 0.9,