diff --git a/include/plat/arm/common/arm_sip_svc.h b/include/plat/arm/common/arm_sip_svc.h
index 68375af..3e25cbc 100644
--- a/include/plat/arm/common/arm_sip_svc.h
+++ b/include/plat/arm/common/arm_sip_svc.h
@@ -1,24 +1,26 @@
 /*
- * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __ARM_SIP_SVC_H__
-#define __ARM_SIP_SVC_H__
+#ifndef ARM_SIP_SVC_H
+#define ARM_SIP_SVC_H
+
+#include <utils_def.h>
 
 /* SMC function IDs for SiP Service queries */
 
-#define ARM_SIP_SVC_CALL_COUNT		0x8200ff00
-#define ARM_SIP_SVC_UID			0x8200ff01
-/*					0x8200ff02 is reserved */
-#define ARM_SIP_SVC_VERSION		0x8200ff03
+#define ARM_SIP_SVC_CALL_COUNT		U(0x8200ff00)
+#define ARM_SIP_SVC_UID			U(0x8200ff01)
+/*					U(0x8200ff02) is reserved */
+#define ARM_SIP_SVC_VERSION		U(0x8200ff03)
 
 /* Function ID for requesting state switch of lower EL */
-#define ARM_SIP_SVC_EXE_STATE_SWITCH	0x82000020
+#define ARM_SIP_SVC_EXE_STATE_SWITCH	U(0x82000020)
 
 /* ARM SiP Service Calls version numbers */
-#define ARM_SIP_SVC_VERSION_MAJOR		0x0
-#define ARM_SIP_SVC_VERSION_MINOR		0x2
+#define ARM_SIP_SVC_VERSION_MAJOR		U(0x0)
+#define ARM_SIP_SVC_VERSION_MINOR		U(0x2)
 
-#endif /* __ARM_SIP_SVC_H__ */
+#endif /* ARM_SIP_SVC_H */
diff --git a/include/plat/arm/common/plat_arm.h b/include/plat/arm/common/plat_arm.h
index bdcb144..e7082d0 100644
--- a/include/plat/arm/common/plat_arm.h
+++ b/include/plat/arm/common/plat_arm.h
@@ -3,8 +3,8 @@
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
-#ifndef __PLAT_ARM_H__
-#define __PLAT_ARM_H__
+#ifndef PLAT_ARM_H
+#define PLAT_ARM_H
 
 #include <bakery_lock.h>
 #include <cassert.h>
@@ -292,4 +292,4 @@
 extern const mmap_region_t plat_arm_mmap[];
 extern const unsigned int arm_pm_idle_states[];
 
-#endif /* __PLAT_ARM_H__ */
+#endif /* PLAT_ARM_H */