Adding copyright headers.
Change-Id: Id9ac22d2811a5a545bebe2d32a11958ea85a9fe5
diff --git a/hf_call.S b/hf_call.S
index 07743ca..7a65f5b 100644
--- a/hf_call.S
+++ b/hf_call.S
@@ -1,3 +1,20 @@
+/*
+ * Copyright 2018 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
.text
.global hf_call