diff --git a/include/lib/smccc.h b/include/lib/smccc.h
index deaeb1d..1a39f24 100644
--- a/include/lib/smccc.h
+++ b/include/lib/smccc.h
@@ -108,9 +108,24 @@
 #define SMC_ARCH_CALL_NOT_REQUIRED	-2
 #define SMC_ARCH_CALL_INVAL_PARAM	-3
 
-/* Various flags passed to SMC handlers */
+/*
+ * Various flags passed to SMC handlers
+ *
+ * Bit 5 and bit 0 of the flag are used to
+ * determine the source security state as
+ * follows:
+ * ---------------------------------
+ *  Bit 5 | Bit 0 | Security state
+ * ---------------------------------
+ *   0        0      SMC_FROM_SECURE
+ *   0        1      SMC_FROM_NON_SECURE
+ *   1        1      SMC_FROM_REALM
+ */
+
 #define SMC_FROM_SECURE		(U(0) << 0)
 #define SMC_FROM_NON_SECURE	(U(1) << 0)
+#define SMC_FROM_REALM		U(0x21)
+#define SMC_FROM_MASK		U(0x21)
 
 #ifndef __ASSEMBLER__
 
@@ -118,8 +133,18 @@
 
 #include <lib/cassert.h>
 
+#if ENABLE_RME
+#define is_caller_non_secure(_f)	(((_f) & SMC_FROM_MASK) \
+					  == SMC_FROM_NON_SECURE)
+#define is_caller_secure(_f)		(((_f) & SMC_FROM_MASK) \
+					  == SMC_FROM_SECURE)
+#define is_caller_realm(_f)		(((_f) & SMC_FROM_MASK) \
+					  == SMC_FROM_REALM)
+#define caller_sec_state(_f)		((_f) & SMC_FROM_MASK)
+#else /* ENABLE_RME */
 #define is_caller_non_secure(_f)	(((_f) & SMC_FROM_NON_SECURE) != U(0))
 #define is_caller_secure(_f)		(!is_caller_non_secure(_f))
+#endif /* ENABLE_RME */
 
 /* The macro below is used to identify a Standard Service SMC call */
 #define is_std_svc_call(_fid)		(GET_SMC_OEN(_fid) == OEN_STD_START)