diff --git a/include/common/runtime_svc.h b/include/common/runtime_svc.h
index b8cf8de..6fe0a94 100644
--- a/include/common/runtime_svc.h
+++ b/include/common/runtime_svc.h
@@ -21,15 +21,15 @@
  * descriptor
  */
 #ifdef AARCH32
-#define RT_SVC_SIZE_LOG2	4
-#define RT_SVC_DESC_INIT	8
-#define RT_SVC_DESC_HANDLE	12
+#define RT_SVC_SIZE_LOG2	U(4)
+#define RT_SVC_DESC_INIT	U(8)
+#define RT_SVC_DESC_HANDLE	U(12)
 #else
-#define RT_SVC_SIZE_LOG2	5
-#define RT_SVC_DESC_INIT	16
-#define RT_SVC_DESC_HANDLE	24
+#define RT_SVC_SIZE_LOG2	U(5)
+#define RT_SVC_DESC_INIT	U(16)
+#define RT_SVC_DESC_HANDLE	U(24)
 #endif /* AARCH32 */
-#define SIZEOF_RT_SVC_DESC	(1 << RT_SVC_SIZE_LOG2)
+#define SIZEOF_RT_SVC_DESC	(U(1) << RT_SVC_SIZE_LOG2)
 
 
 /*
@@ -43,9 +43,9 @@
  * handler and so the total number of runtime services is 32.
  */
 #if SMCCC_MAJOR_VERSION == 1
-#define MAX_RT_SVCS		128
+#define MAX_RT_SVCS		U(128)
 #elif SMCCC_MAJOR_VERSION == 2
-#define MAX_RT_SVCS		32
+#define MAX_RT_SVCS		U(32)
 #endif
 
 #ifndef __ASSEMBLY__
@@ -146,35 +146,42 @@
 
 #if SMCCC_MAJOR_VERSION == 1
 /*
- * This macro combines the call type and the owning entity number corresponding
- * to a runtime service to generate a unique owning entity number. This unique
- * oen is used to access an entry in the 'rt_svc_descs_indices' array. The entry
- * contains the index of the service descriptor in the 'rt_svc_descs' array.
+ * This function combines the call type and the owning entity number
+ * corresponding to a runtime service to generate a unique owning entity number.
+ * This unique oen is used to access an entry in the 'rt_svc_descs_indices'
+ * array. The entry contains the index of the service descriptor in the
+ * 'rt_svc_descs' array.
  */
-#define get_unique_oen(oen, call_type)				\
-	(((uint32_t)(oen) & FUNCID_OEN_MASK) |			\
-	(((uint32_t)(call_type) & FUNCID_TYPE_MASK) << FUNCID_OEN_WIDTH))
+static inline uint32_t get_unique_oen(uint32_t oen, uint32_t call_type)
+{
+	return ((call_type & FUNCID_TYPE_MASK) << FUNCID_OEN_WIDTH) |
+		(oen & FUNCID_OEN_MASK);
+}
 
 /*
- * This macro generates the unique owning entity number from the SMC Function
+ * This function generates the unique owning entity number from the SMC Function
  * ID. This unique oen is used to access an entry in the 'rt_svc_descs_indices'
  * array to invoke the corresponding runtime service handler during SMC
  * handling.
  */
-#define get_unique_oen_from_smc_fid(fid)			\
-	get_unique_oen(GET_SMC_OEN(fid), GET_SMC_TYPE(fid))
+static inline uint32_t get_unique_oen_from_smc_fid(uint32_t fid)
+{
+	return get_unique_oen(GET_SMC_OEN(fid), GET_SMC_TYPE(fid));
+}
 
 #elif SMCCC_MAJOR_VERSION == 2
 
 /*
- * This macro combines the owning entity number corresponding to a runtime
+ * This function combines the owning entity number corresponding to a runtime
  * service with one extra bit for the vendor namespace to generate an index into
  * the 'rt_svc_descs_indices' array. The entry contains the index of the service
  * descriptor in the 'rt_svc_descs' array.
  */
-#define get_rt_desc_idx(oen, is_vendor)				\
-	(((uint32_t)(oen) & FUNCID_OEN_MASK) |			\
-	(((uint32_t)(is_vendor) & 1U) << FUNCID_OEN_WIDTH))
+static inline uint32_t get_rt_desc_idx(uint32_t oen, uint32_t is_vendor)
+{
+	return ((is_vendor & 1U) << FUNCID_OEN_WIDTH) |
+		(oen & FUNCID_OEN_MASK);
+}
 
 #endif