diff --git a/include/arch/aarch64/arch.h b/include/arch/aarch64/arch.h
index 1053006..5949370 100644
--- a/include/arch/aarch64/arch.h
+++ b/include/arch/aarch64/arch.h
@@ -448,6 +448,7 @@
 #define SCR_ECVEN_BIT		(UL(1) << 28)
 #define SCR_FGTEN_BIT		(UL(1) << 27)
 #define SCR_ATA_BIT		(UL(1) << 26)
+#define SCR_EnSCXT_BIT		(UL(1) << 25)
 #define SCR_FIEN_BIT		(UL(1) << 21)
 #define SCR_EEL2_BIT		(UL(1) << 18)
 #define SCR_API_BIT		(UL(1) << 17)
@@ -609,6 +610,7 @@
 #define SPSR_M_MASK		U(0x1)
 #define SPSR_M_AARCH64		U(0x0)
 #define SPSR_M_AARCH32		U(0x1)
+#define SPSR_M_EL2H		U(0x9)
 
 #define SPSR_EL_SHIFT		U(2)
 #define SPSR_EL_WIDTH		U(2)
diff --git a/include/services/gtsi_svc.h b/include/services/gtsi_svc.h
new file mode 100644
index 0000000..cb942ed
--- /dev/null
+++ b/include/services/gtsi_svc.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef GTSI_SVC_H
+#define GTSI_SVC_H
+
+/* GTSI error codes. */
+#define GTSI_SUCCESS			0
+#define GTSI_ERROR_NOT_SUPPORTED	-1
+#define GTSI_ERROR_INVALID_ADDRESS	-2
+#define GTSI_ERROR_INVALID_PAS		-3
+
+/* The macros below are used to identify GTSI calls from the SMC function ID */
+#define GTSI_FNUM_MIN_VALUE	U(0x100)
+#define GTSI_FNUM_MAX_VALUE	U(0x101)
+#define is_gtsi_fid(fid) __extension__ ({		\
+	__typeof__(fid) _fid = (fid);			\
+	((GET_SMC_NUM(_fid) >= GTSI_FNUM_MIN_VALUE) &&	\
+	 (GET_SMC_NUM(_fid) <= GTSI_FNUM_MAX_VALUE)); })
+
+/* Get GTSI fastcall std FID from function number */
+#define GTSI_FID(smc_cc, func_num)			\
+	((SMC_TYPE_FAST << FUNCID_TYPE_SHIFT)	|	\
+	 ((smc_cc) << FUNCID_CC_SHIFT)		|	\
+	 (OEN_STD_START << FUNCID_OEN_SHIFT)	|	\
+	 ((func_num) << FUNCID_NUM_SHIFT))
+
+#define GRAN_TRANS_TO_REALM_FNUM	U(0x100)
+#define GRAN_TRANS_TO_NS_FNUM		U(0x101)
+
+#define SMC_ASC_MARK_REALM	GTSI_FID(SMC_64, GRAN_TRANS_TO_REALM_FNUM)
+#define SMC_ASC_MARK_NONSECURE	GTSI_FID(SMC_64, GRAN_TRANS_TO_NS_FNUM)
+
+#define GRAN_TRANS_RET_BAD_ADDR		-2
+#define GRAN_TRANS_RET_BAD_PAS		-3
+
+#endif /* GTSI_SVC_H */
diff --git a/include/services/rmi_svc.h b/include/services/rmi_svc.h
new file mode 100644
index 0000000..9106f08
--- /dev/null
+++ b/include/services/rmi_svc.h
@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2021, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef RMI_SVC_H
+#define RMI_SVC_H
+
+#include <lib/smccc.h>
+#include <lib/utils_def.h>
+
+/* RMI error codes. */
+#define RMI_SUCCESS			0
+#define RMI_ERROR_NOT_SUPPORTED		-1
+#define RMI_ERROR_INVALID_ADDRESS	-2
+#define RMI_ERROR_INVALID_PAS		-3
+
+/* The macros below are used to identify RMI calls from the SMC function ID */
+#define RMI_FNUM_MIN_VALUE	U(0x00)
+#define RMI_FNUM_MAX_VALUE	U(0x20)
+#define is_rmi_fid(fid) __extension__ ({		\
+	__typeof__(fid) _fid = (fid);			\
+	((GET_SMC_NUM(_fid) >= RMI_FNUM_MIN_VALUE) &&	\
+	 (GET_SMC_NUM(_fid) <= RMI_FNUM_MAX_VALUE) &&	\
+	 (GET_SMC_TYPE(_fid) == SMC_TYPE_FAST)	   &&	\
+	 (GET_SMC_CC(_fid) == SMC_64)              &&	\
+	 (GET_SMC_OEN(_fid) == OEN_ARM_START)      &&	\
+	 ((_fid & 0x00FE0000) == 0U)); })
+
+/* Get RMI fastcall std FID from function number */
+#define RMI_FID(smc_cc, func_num)			\
+	((SMC_TYPE_FAST << FUNCID_TYPE_SHIFT)	|	\
+	((smc_cc) << FUNCID_CC_SHIFT)		|	\
+	(OEN_ARM_START << FUNCID_OEN_SHIFT)	|	\
+	((func_num) << FUNCID_NUM_SHIFT))
+
+/*
+ * SMC_RMM_INIT_COMPLETE is the only function in the RMI that originates from
+ * the Realm world and is handled by the RMMD. The remaining functions are
+ * always invoked by the Normal world, forwarded by RMMD and handled by the
+ * RMM
+ */
+#define RMI_FNUM_REQ_COMPLETE		U(0x10)
+#define RMI_FNUM_VERSION_REQ		U(0x00)
+
+#define RMI_FNUM_GRAN_NS_REALM		U(0x01)
+#define RMI_FNUM_GRAN_REALM_NS		U(0x10)
+
+/* RMI SMC64 FIDs handled by the RMMD */
+#define RMI_RMM_REQ_COMPLETE		RMI_FID(SMC_64, RMI_FNUM_REQ_COMPLETE)
+#define RMI_RMM_REQ_VERSION		RMI_FID(SMC_64, RMI_FNUM_VERSION_REQ)
+
+#define RMI_RMM_GRANULE_DELEGATE	RMI_FID(SMC_64, RMI_FNUM_GRAN_NS_REALM)
+#define RMI_RMM_GRANULE_UNDELEGATE	RMI_FID(SMC_64, RMI_FNUM_GRAN_REALM_NS)
+
+
+#define RMI_ABI_VERSION_GET_MAJOR(_version) ((_version) >> 16)
+#define RMI_ABI_VERSION_GET_MINOR(_version) ((_version) & 0xFFFF)
+
+/* Reserve a special value for MBZ parameters. */
+#define RMI_PARAM_MBZ			U(0x0)
+
+#endif /* RMI_SVC_H */
diff --git a/include/services/rmmd_svc.h b/include/services/rmmd_svc.h
new file mode 100644
index 0000000..132973b
--- /dev/null
+++ b/include/services/rmmd_svc.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2021, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef RMMD_SVC_H
+#define RMMD_SVC_H
+
+#ifndef __ASSEMBLER__
+#include <stdint.h>
+
+int rmmd_setup(void);
+uint64_t rmmd_rmi_handler(uint32_t smc_fid,
+		uint64_t x1,
+		uint64_t x2,
+		uint64_t x3,
+		uint64_t x4,
+		void *cookie,
+		void *handle,
+		uint64_t flags);
+
+uint64_t rmmd_gtsi_handler(uint32_t smc_fid,
+		uint64_t x1,
+		uint64_t x2,
+		uint64_t x3,
+		uint64_t x4,
+		void *cookie,
+		void *handle,
+		uint64_t flags);
+
+#endif /* __ASSEMBLER__ */
+
+#endif /* RMMD_SVC_H */