diff --git a/include/runtime_services/psci.h b/include/runtime_services/psci.h
new file mode 100644
index 0000000..1ecfc63
--- /dev/null
+++ b/include/runtime_services/psci.h
@@ -0,0 +1,224 @@
+/*
+ * Copyright (c) 2018, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/*
+ * Definitions related to the Power State Coordination Interface (PSCI)
+ * as per the SMC Calling Convention.
+ *
+ * PSCI calls are a subset of the Standard Service Calls.
+ */
+
+#ifndef __PSCI_H__
+#define __PSCI_H__
+
+#ifndef __ASSEMBLY__
+#include <assert.h>
+#include <platform_def.h>
+#include <stdbool.h>
+#include <stdint.h>
+#endif
+
+/*******************************************************************************
+ * Macro to create the array entry for psci_functions[]
+ ******************************************************************************/
+#define DEFINE_PSCI_FUNC(_func_id, _mandatory) \
+	{ SMC_##_func_id, _mandatory, "SMC_" # _func_id }
+
+/*******************************************************************************
+ * Defines for runtime services function ids
+ ******************************************************************************/
+#define SMC_PSCI_VERSION			0x84000000
+#define SMC_PSCI_CPU_SUSPEND_AARCH32		0x84000001
+#define SMC_PSCI_CPU_SUSPEND_AARCH64		0xc4000001
+#define SMC_PSCI_CPU_OFF			0x84000002
+#define SMC_PSCI_CPU_ON_AARCH32			0x84000003
+#define SMC_PSCI_CPU_ON_AARCH64			0xc4000003
+#define SMC_PSCI_AFFINITY_INFO_AARCH32		0x84000004
+#define SMC_PSCI_AFFINITY_INFO_AARCH64		0xc4000004
+#define SMC_PSCI_MIG_AARCH32			0x84000005
+#define SMC_PSCI_MIG_AARCH64			0xc4000005
+#define SMC_PSCI_MIG_INFO_TYPE			0x84000006
+#define SMC_PSCI_MIG_INFO_UP_CPU_AARCH32	0x84000007
+#define SMC_PSCI_MIG_INFO_UP_CPU_AARCH64	0xc4000007
+#define SMC_PSCI_SYSTEM_OFF			0x84000008
+#define SMC_PSCI_SYSTEM_RESET			0x84000009
+#define SMC_PSCI_FEATURES			0x8400000a
+#define SMC_PSCI_CPU_FREEZE			0x8400000b
+#define SMC_PSCI_CPU_DEFAULT_SUSPEND32		0x8400000c
+#define SMC_PSCI_CPU_DEFAULT_SUSPEND64		0xc400000c
+#define SMC_PSCI_CPU_HW_STATE32			0x8400000d
+#define SMC_PSCI_CPU_HW_STATE64			0xc400000d
+#define SMC_PSCI_SYSTEM_SUSPEND32		0x8400000e
+#define SMC_PSCI_SYSTEM_SUSPEND64		0xc400000e
+#define SMC_PSCI_SET_SUSPEND_MODE		0x8400000f
+#define SMC_PSCI_STAT_RESIDENCY32		0x84000010
+#define SMC_PSCI_STAT_RESIDENCY64		0xc4000010
+#define SMC_PSCI_STAT_COUNT32			0x84000011
+#define SMC_PSCI_STAT_COUNT64			0xc4000011
+#define SMC_PSCI_RESET2_AARCH32			0x84000012
+#define SMC_PSCI_RESET2_AARCH64			0xc4000012
+#define SMC_PSCI_MEM_PROTECT			0x84000013
+#define SMC_PSCI_MEM_PROTECT_CHECK_RANGE32	0x84000014
+#define SMC_PSCI_MEM_PROTECT_CHECK_RANGE64	0xc4000014
+
+/*
+ * Architecture-specific SMC function IDs
+ */
+#ifndef AARCH32
+#define SMC_PSCI_CPU_SUSPEND		SMC_PSCI_CPU_SUSPEND_AARCH64
+#define SMC_PSCI_CPU_ON			SMC_PSCI_CPU_ON_AARCH64
+#define SMC_PSCI_AFFINITY_INFO		SMC_PSCI_AFFINITY_INFO_AARCH64
+#define SMC_PSCI_MIG			SMC_PSCI_MIG_AARCH64
+#define SMC_PSCI_MIG_INFO_UP_CPU	SMC_PSCI_MIG_INFO_UP_CPU_AARCH64
+#define SMC_PSCI_CPU_DEFAULT_SUSPEND	SMC_PSCI_CPU_DEFAULT_SUSPEND64
+#define SMC_PSCI_CPU_HW_STATE		SMC_PSCI_CPU_HW_STATE64
+#define SMC_PSCI_SYSTEM_SUSPEND		SMC_PSCI_SYSTEM_SUSPEND64
+#define SMC_PSCI_STAT_RESIDENCY		SMC_PSCI_STAT_RESIDENCY64
+#define SMC_PSCI_STAT_COUNT		SMC_PSCI_STAT_COUNT64
+#define SMC_PSCI_RESET2			SMC_PSCI_RESET2_AARCH64
+#define SMC_PSCI_MEM_PROTECT_CHECK	SMC_PSCI_MEM_PROTECT_CHECK_RANGE64
+#else
+#define SMC_PSCI_CPU_SUSPEND		SMC_PSCI_CPU_SUSPEND_AARCH32
+#define SMC_PSCI_CPU_ON			SMC_PSCI_CPU_ON_AARCH32
+#define SMC_PSCI_AFFINITY_INFO		SMC_PSCI_AFFINITY_INFO_AARCH32
+#define SMC_PSCI_MIG			SMC_PSCI_MIG_AARCH32
+#define SMC_PSCI_MIG_INFO_UP_CPU	SMC_PSCI_MIG_INFO_UP_CPU_AARCH32
+#define SMC_PSCI_CPU_DEFAULT_SUSPEND	SMC_PSCI_CPU_DEFAULT_SUSPEND32
+#define SMC_PSCI_CPU_HW_STATE		SMC_PSCI_CPU_HW_STATE32
+#define SMC_PSCI_SYSTEM_SUSPEND		SMC_PSCI_SYSTEM_SUSPEND32
+#define SMC_PSCI_STAT_RESIDENCY		SMC_PSCI_STAT_RESIDENCY32
+#define SMC_PSCI_STAT_COUNT		SMC_PSCI_STAT_COUNT32
+#define SMC_PSCI_RESET2			SMC_PSCI_RESET2_AARCH32
+#define SMC_PSCI_MEM_PROTECT_CHECK	SMC_PSCI_MEM_PROTECT_CHECK_RANGE32
+#endif
+
+/*
+ * Number of PSCI calls defined in the PSCI specification.
+ */
+#define PSCI_NUM_CALLS				33
+
+#ifndef __ASSEMBLY__
+typedef struct {
+	uint32_t	id;
+	bool		mandatory;
+	const char	*str;
+} psci_function_t;
+
+extern const psci_function_t psci_functions[PSCI_NUM_CALLS];
+#endif /* __ASSEMBLY__ */
+
+/*******************************************************************************
+ * PSCI Migrate specific defines
+ ******************************************************************************/
+#define PSCI_TOS_UP_MIG_CAP	0
+#define PSCI_TOS_NOT_UP_MIG_CAP	1
+#define PSCI_TOS_NOT_PRESENT_MP	2
+
+/*******************************************************************************
+ * PSCI CPU_SUSPEND 'power_state' parameter specific defines
+ ******************************************************************************/
+/* Original format */
+#define PSTATE_ID_SHIFT		0
+#define PSTATE_TYPE_SHIFT	16
+#define PSTATE_AFF_LVL_SHIFT	24
+#define PSTATE_ID_MASK		0xFFFF
+#define PSTATE_AFF_LVL_MASK	0x3
+
+#define psci_state_id_valid(state_id)			\
+	(((state_id) & ~PSTATE_ID_MASK) == 0)
+
+#define psci_affinity_level_valid(aff_level)		\
+	(((aff_level) & ~PSTATE_AFF_LVL_MASK) == 0)
+
+/* Extended format */
+#define PSTATE_ID_SHIFT_EXT	0
+#define PSTATE_TYPE_SHIFT_EXT	30
+#define PSTATE_ID_MASK_EXT	0xFFFFFFF
+
+#define psci_state_id_ext_valid(state_id)		\
+	(((state_id) & ~PSTATE_ID_MASK_EXT) == 0)
+
+/* Definitions common to original and extended StateID formats */
+#define PSTATE_TYPE_MASK	0x1
+
+#define PSTATE_TYPE_STANDBY	0x0
+#define PSTATE_TYPE_POWERDOWN	0x1
+
+#define PSTATE_AFF_LVL_0	0
+#define PSTATE_AFF_LVL_1	1
+#define PSTATE_AFF_LVL_2	2
+#define PSTATE_AFF_LVL_3	3
+
+#define psci_state_type_valid(state_type)		\
+	(((state_type) & ~PSTATE_TYPE_MASK) == 0)
+
+/*******************************************************************************
+ * PSCI 'Feature Flags' defines for CPU_SUSPEND
+ ******************************************************************************/
+#define CPU_SUSPEND_FEAT_OS_INIT_MODE_SHIFT	0
+#define CPU_SUSPEND_FEAT_PSTATE_FORMAT_SHIFT	1
+#define CPU_SUSPEND_FEAT_PSTATE_FORMAT_ORIGINAL	0
+#define CPU_SUSPEND_FEAT_PSTATE_FORMAT_EXTENDED	1
+
+#define CPU_SUSPEND_FEAT_VALID_MASK			\
+	((1 << CPU_SUSPEND_FEAT_OS_INIT_MODE_SHIFT) |	\
+	 (1 << CPU_SUSPEND_FEAT_PSTATE_FORMAT_SHIFT))
+
+/*******************************************************************************
+ * PSCI 'Feature Flags' defines for functions other than CPU_SUSPEND
+ ******************************************************************************/
+#define PSCI_FEATURE_FLAGS_ZERO			0
+
+#ifndef __ASSEMBLY__
+
+/*
+ * Construct the local State-ID for a particular level according to
+ * the platform specific local state-ID width.
+ */
+#define psci_make_local_state_id(level, local_state) \
+		(((local_state) & ((1 << PLAT_LOCAL_PSTATE_WIDTH) - 1)) \
+			<< (PLAT_LOCAL_PSTATE_WIDTH * (level)))
+#endif
+
+/*******************************************************************************
+ * PSCI version
+ ******************************************************************************/
+#define PSCI_MAJOR_VER		1
+#define PSCI_MINOR_VER		1
+#define PSCI_MAJOR_VER_SHIFT	16
+#define PSCI_MAJOR_VER_MASK	0xFFFF0000
+#define PSCI_VERSION(major, minor)	((major << PSCI_MAJOR_VER_SHIFT) \
+					| minor)
+
+/*******************************************************************************
+ * PSCI error codes
+ ******************************************************************************/
+#define PSCI_E_SUCCESS		0
+#define PSCI_E_NOT_SUPPORTED	-1
+#define PSCI_E_INVALID_PARAMS	-2
+#define PSCI_E_DENIED		-3
+#define PSCI_E_ALREADY_ON	-4
+#define PSCI_E_ON_PENDING	-5
+#define PSCI_E_INTERN_FAIL	-6
+#define PSCI_E_NOT_PRESENT	-7
+#define PSCI_E_DISABLED		-8
+#define PSCI_E_INVALID_ADDRESS	-9
+
+/*******************************************************************************
+ * PSCI affinity state related constants.
+ ******************************************************************************/
+#define PSCI_STATE_ON		0x0
+#define PSCI_STATE_OFF		0x1
+#define PSCI_STATE_ON_PENDING	0x2
+
+/*******************************************************************************
+ * PSCI node hardware state related constants.
+ ******************************************************************************/
+#define PSCI_HW_STATE_ON	0x0
+#define PSCI_HW_STATE_OFF	0x1
+#define PSCI_HW_STATE_STANDBY	0x2
+
+#endif /* __PSCI_H__ */