diff --git a/include/plat/common/plat_trng.h b/include/plat/common/plat_trng.h
new file mode 100644
index 0000000..a9f73b6
--- /dev/null
+++ b/include/plat/common/plat_trng.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2021, ARM Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef PLAT_TRNG_H
+#define PLAT_TRNG_H
+
+#include <tools_share/uuid.h>
+
+/* TRNG platform functions */
+
+extern uuid_t plat_trng_uuid;
+void plat_entropy_setup(void);
+bool plat_get_entropy(uint64_t *out);
+
+#endif /* PLAT_TRNG_H */
diff --git a/include/plat/common/platform.h b/include/plat/common/platform.h
index ebcc855..1def86e 100644
--- a/include/plat/common/platform.h
+++ b/include/plat/common/platform.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -13,6 +13,9 @@
 #if defined(SPD_spmd)
  #include <services/spm_core_manifest.h>
 #endif
+#if TRNG_SUPPORT
+#include "plat_trng.h"
+#endif
 
 /*******************************************************************************
  * Forward declarations
diff --git a/include/services/trng_svc.h b/include/services/trng_svc.h
new file mode 100644
index 0000000..ed4d557
--- /dev/null
+++ b/include/services/trng_svc.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2021, ARM Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef TRNG_SVC_H
+#define TRNG_SVC_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <lib/smccc.h>
+
+/* SMC function IDs for TRNG queries */
+#define ARM_TRNG_VERSION	U(0x84000050)
+#define ARM_TRNG_FEATURES	U(0x84000051)
+#define ARM_TRNG_GET_UUID	U(0x84000052)
+#define ARM_TRNG_RND32		U(0x84000053)
+#define ARM_TRNG_RND64		U(0xc4000053)
+
+/* TRNG version numbers */
+#define TRNG_VERSION_MAJOR	(0x1)
+#define TRNG_VERSION_MINOR	(0x0)
+
+/* TRNG Error Numbers */
+#define TRNG_E_SUCCESS		(0)
+#define TRNG_E_NOT_SUPPORTED	(-1)
+#define TRNG_E_INVALID_PARAMS	(-2)
+#define TRNG_E_NO_ENTROPY	(-3)
+#define TRNG_E_NOT_IMPLEMENTED	(-4)
+
+#if TRNG_SUPPORT
+void trng_setup(void);
+bool is_trng_fid(uint32_t smc_fid);
+#else
+static inline void trng_setup(void)
+{
+}
+
+static inline bool is_trng_fid(uint32_t smc_fid)
+{
+	return false;
+}
+#endif
+uintptr_t trng_smc_handler(
+	uint32_t smc_fid,
+	u_register_t x1,
+	u_register_t x2,
+	u_register_t x3,
+	u_register_t x4,
+	void *cookie,
+	void *handle,
+	u_register_t flags
+);
+
+#endif /* TRNG_SVC_H */