Adding upstream version 2.10.0+dfsg.upstream/2.10.0+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 1382 insertions, 0 deletions

diff --git a/services/std_svc/rmmd/aarch64/rmmd_helpers.S b/services/std_svc/rmmd/aarch64/rmmd_helpers.S
new file mode 100644
index 0000000..6229baf
--- /dev/null
+++ b/services/std_svc/rmmd/aarch64/rmmd_helpers.S
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2021, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include "../rmmd_private.h"
+#include <asm_macros.S>
+
+	.global rmmd_rmm_enter
+	.global rmmd_rmm_exit
+
+	/* ---------------------------------------------------------------------
+	 * This function is called with SP_EL0 as stack. Here we stash our EL3
+	 * callee-saved registers on to the stack as a part of saving the C
+	 * runtime and enter the secure payload.
+	 * 'x0' contains a pointer to the memory where the address of the C
+	 *  runtime context is to be saved.
+	 * ---------------------------------------------------------------------
+	 */
+func rmmd_rmm_enter
+	/* Make space for the registers that we're going to save */
+	mov	x3, sp
+	str	x3, [x0, #0]
+	sub	sp, sp, #RMMD_C_RT_CTX_SIZE
+
+	/* Save callee-saved registers on to the stack */
+	stp	x19, x20, [sp, #RMMD_C_RT_CTX_X19]
+	stp	x21, x22, [sp, #RMMD_C_RT_CTX_X21]
+	stp	x23, x24, [sp, #RMMD_C_RT_CTX_X23]
+	stp	x25, x26, [sp, #RMMD_C_RT_CTX_X25]
+	stp	x27, x28, [sp, #RMMD_C_RT_CTX_X27]
+	stp	x29, x30, [sp, #RMMD_C_RT_CTX_X29]
+
+	/* ---------------------------------------------------------------------
+	 * Everything is setup now. el3_exit() will use the secure context to
+	 * restore to the general purpose and EL3 system registers to ERET
+	 * into the secure payload.
+	 * ---------------------------------------------------------------------
+	 */
+	b	el3_exit
+endfunc rmmd_rmm_enter
+
+	/* ---------------------------------------------------------------------
+	 * This function is called with 'x0' pointing to a C runtime context.
+	 * It restores the saved registers and jumps to that runtime with 'x0'
+	 * as the new SP register. This destroys the C runtime context that had
+	 * been built on the stack below the saved context by the caller. Later
+	 * the second parameter 'x1' is passed as a return value to the caller.
+	 * ---------------------------------------------------------------------
+	 */
+func rmmd_rmm_exit
+	/* Restore the previous stack */
+	mov	sp, x0
+
+	/* Restore callee-saved registers on to the stack */
+	ldp	x19, x20, [x0, #(RMMD_C_RT_CTX_X19 - RMMD_C_RT_CTX_SIZE)]
+	ldp	x21, x22, [x0, #(RMMD_C_RT_CTX_X21 - RMMD_C_RT_CTX_SIZE)]
+	ldp	x23, x24, [x0, #(RMMD_C_RT_CTX_X23 - RMMD_C_RT_CTX_SIZE)]
+	ldp	x25, x26, [x0, #(RMMD_C_RT_CTX_X25 - RMMD_C_RT_CTX_SIZE)]
+	ldp	x27, x28, [x0, #(RMMD_C_RT_CTX_X27 - RMMD_C_RT_CTX_SIZE)]
+	ldp	x29, x30, [x0, #(RMMD_C_RT_CTX_X29 - RMMD_C_RT_CTX_SIZE)]
+
+	/* ---------------------------------------------------------------------
+	 * This should take us back to the instruction after the call to the
+	 * last rmmd_rmm_enter().* Place the second parameter to x0
+	 * so that the caller will see it as a return value from the original
+	 * entry call.
+	 * ---------------------------------------------------------------------
+	 */
+	mov	x0, x1
+	ret
+endfunc rmmd_rmm_exit
diff --git a/services/std_svc/rmmd/rmmd.mk b/services/std_svc/rmmd/rmmd.mk
new file mode 100644
index 0000000..bcf54e1
--- /dev/null
+++ b/services/std_svc/rmmd/rmmd.mk
@@ -0,0 +1,19 @@
+#
+# Copyright (c) 2021-2022, ARM Limited and Contributors. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
+ifneq (${ARCH},aarch64)
+        $(error "Error: RMMD is only supported on aarch64.")
+endif
+
+include services/std_svc/rmmd/trp/trp.mk
+
+RMMD_SOURCES	+=	$(addprefix services/std_svc/rmmd/,	\
+			${ARCH}/rmmd_helpers.S			\
+			rmmd_main.c				\
+			rmmd_attest.c)
+
+# Let the top-level Makefile know that we intend to include RMM image
+NEED_RMM	:=	yes
diff --git a/services/std_svc/rmmd/rmmd_attest.c b/services/std_svc/rmmd/rmmd_attest.c
new file mode 100644
index 0000000..25adf50
--- /dev/null
+++ b/services/std_svc/rmmd/rmmd_attest.c
@@ -0,0 +1,153 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+#include <stdint.h>
+#include <string.h>
+
+#include <common/debug.h>
+#include <lib/spinlock.h>
+#include <lib/xlat_tables/xlat_tables_v2.h>
+#include <plat/common/platform.h>
+#include "rmmd_private.h"
+#include <services/rmmd_svc.h>
+
+static spinlock_t lock;
+
+/* For printing Realm attestation token hash */
+#define DIGITS_PER_BYTE				2UL
+#define LENGTH_OF_TERMINATING_ZERO_IN_BYTES	1UL
+#define BYTES_PER_LINE_BASE			4UL
+
+static void print_challenge(uint8_t *hash, size_t hash_size)
+{
+	size_t leftover;
+	/*
+	 * bytes_per_line is always a power of two, so it can be used to
+	 * construct mask with it when it is necessary to count remainder.
+	 *
+	 */
+	const size_t bytes_per_line = 1 << BYTES_PER_LINE_BASE;
+	char hash_text[(1 << BYTES_PER_LINE_BASE) * DIGITS_PER_BYTE +
+		LENGTH_OF_TERMINATING_ZERO_IN_BYTES];
+	const char hex_chars[] = {'0', '1', '2', '3', '4', '5', '6', '7',
+				  '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
+	unsigned int i;
+
+	for (i = 0U; i < hash_size; ++i) {
+		hash_text[(i & (bytes_per_line - 1)) * DIGITS_PER_BYTE] =
+			hex_chars[hash[i] >> 4];
+		hash_text[(i & (bytes_per_line - 1)) * DIGITS_PER_BYTE + 1] =
+			hex_chars[hash[i] & 0x0f];
+		if (((i + 1) & (bytes_per_line - 1)) == 0U) {
+			hash_text[bytes_per_line * DIGITS_PER_BYTE] = '\0';
+			VERBOSE("hash part %u = %s\n",
+				(i >> BYTES_PER_LINE_BASE) + 1, hash_text);
+		}
+	}
+
+	leftover = (size_t)i & (bytes_per_line - 1);
+
+	if (leftover != 0UL) {
+		hash_text[leftover * DIGITS_PER_BYTE] = '\0';
+		VERBOSE("hash part %u = %s\n", (i >> BYTES_PER_LINE_BASE) + 1,
+			hash_text);
+	}
+}
+
+/*
+ * Helper function to validate that the buffer base and length are
+ * within range.
+ */
+static int validate_buffer_params(uint64_t buf_pa, uint64_t buf_len)
+{
+	unsigned long shared_buf_page;
+	uintptr_t shared_buf_base;
+
+	(void)plat_rmmd_get_el3_rmm_shared_mem(&shared_buf_base);
+
+	shared_buf_page = shared_buf_base & ~PAGE_SIZE_MASK;
+
+	/* Validate the buffer pointer */
+	if ((buf_pa & ~PAGE_SIZE_MASK) != shared_buf_page) {
+		ERROR("Buffer PA out of range\n");
+		return E_RMM_BAD_ADDR;
+	}
+
+	/* Validate the size of the shared area */
+	if (((buf_pa + buf_len - 1UL) & ~PAGE_SIZE_MASK) != shared_buf_page) {
+		ERROR("Invalid buffer length\n");
+		return E_RMM_INVAL;
+	}
+
+	return 0; /* No error */
+}
+
+int rmmd_attest_get_platform_token(uint64_t buf_pa, uint64_t *buf_size,
+				   uint64_t c_size)
+{
+	int err;
+	uint8_t temp_buf[SHA512_DIGEST_SIZE];
+
+	err = validate_buffer_params(buf_pa, *buf_size);
+	if (err != 0) {
+		return err;
+	}
+
+	if ((c_size != SHA256_DIGEST_SIZE) &&
+	    (c_size != SHA384_DIGEST_SIZE) &&
+	    (c_size != SHA512_DIGEST_SIZE)) {
+		ERROR("Invalid hash size: %lu\n", c_size);
+		return E_RMM_INVAL;
+	}
+
+	spin_lock(&lock);
+
+	(void)memcpy(temp_buf, (void *)buf_pa, c_size);
+
+	print_challenge((uint8_t *)temp_buf, c_size);
+
+	/* Get the platform token. */
+	err = plat_rmmd_get_cca_attest_token((uintptr_t)buf_pa,
+		buf_size, (uintptr_t)temp_buf, c_size);
+
+	if (err != 0) {
+		ERROR("Failed to get platform token: %d.\n", err);
+		err = E_RMM_UNK;
+	}
+
+	spin_unlock(&lock);
+
+	return err;
+}
+
+int rmmd_attest_get_signing_key(uint64_t buf_pa, uint64_t *buf_size,
+				uint64_t ecc_curve)
+{
+	int err;
+
+	err = validate_buffer_params(buf_pa, *buf_size);
+	if (err != 0) {
+		return err;
+	}
+
+	if (ecc_curve != ATTEST_KEY_CURVE_ECC_SECP384R1) {
+		ERROR("Invalid ECC curve specified\n");
+		return E_RMM_INVAL;
+	}
+
+	spin_lock(&lock);
+
+	/* Get the Realm attestation key. */
+	err = plat_rmmd_get_cca_realm_attest_key((uintptr_t)buf_pa, buf_size,
+						 (unsigned int)ecc_curve);
+	if (err != 0) {
+		ERROR("Failed to get attestation key: %d.\n", err);
+		err =  E_RMM_UNK;
+	}
+
+	spin_unlock(&lock);
+
+	return err;
+}
diff --git a/services/std_svc/rmmd/rmmd_initial_context.h b/services/std_svc/rmmd/rmmd_initial_context.h
new file mode 100644
index 0000000..d7a743d
--- /dev/null
+++ b/services/std_svc/rmmd/rmmd_initial_context.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2021, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef RMMD_INITIAL_CONTEXT_H
+#define RMMD_INITIAL_CONTEXT_H
+
+#include <arch.h>
+
+/*
+ * SPSR_EL2
+ *   M=0x9 (0b1001 EL2h)
+ *   M[4]=0
+ *   DAIF=0xF Exceptions masked on entry.
+ *   BTYPE=0  BTI not yet supported.
+ *   SSBS=0   Not yet supported.
+ *   IL=0     Not an illegal exception return.
+ *   SS=0     Not single stepping.
+ *   PAN=1    RMM shouldn't access realm memory.
+ *   UAO=0
+ *   DIT=0
+ *   TCO=0
+ *   NZCV=0
+ */
+#define REALM_SPSR_EL2		(					\
+					SPSR_M_EL2H			| \
+					(0xF << SPSR_DAIF_SHIFT)	| \
+					SPSR_PAN_BIT			\
+				)
+
+#endif /* RMMD_INITIAL_CONTEXT_H */
diff --git a/services/std_svc/rmmd/rmmd_main.c b/services/std_svc/rmmd/rmmd_main.c
new file mode 100644
index 0000000..8b78b13
--- /dev/null
+++ b/services/std_svc/rmmd/rmmd_main.c
@@ -0,0 +1,485 @@
+/*
+ * Copyright (c) 2021-2023, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <stdint.h>
+#include <string.h>
+
+#include <arch_helpers.h>
+#include <arch_features.h>
+#include <bl31/bl31.h>
+#include <common/debug.h>
+#include <common/runtime_svc.h>
+#include <context.h>
+#include <lib/el3_runtime/context_mgmt.h>
+#include <lib/el3_runtime/cpu_data.h>
+#include <lib/el3_runtime/pubsub.h>
+#include <lib/extensions/pmuv3.h>
+#include <lib/extensions/sys_reg_trace.h>
+#include <lib/gpt_rme/gpt_rme.h>
+
+#include <lib/spinlock.h>
+#include <lib/utils.h>
+#include <lib/xlat_tables/xlat_tables_v2.h>
+#include <plat/common/common_def.h>
+#include <plat/common/platform.h>
+#include <platform_def.h>
+#include <services/rmmd_svc.h>
+#include <smccc_helpers.h>
+#include <lib/extensions/sme.h>
+#include <lib/extensions/sve.h>
+#include "rmmd_initial_context.h"
+#include "rmmd_private.h"
+
+/*******************************************************************************
+ * RMM boot failure flag
+ ******************************************************************************/
+static bool rmm_boot_failed;
+
+/*******************************************************************************
+ * RMM context information.
+ ******************************************************************************/
+rmmd_rmm_context_t rmm_context[PLATFORM_CORE_COUNT];
+
+/*******************************************************************************
+ * RMM entry point information. Discovered on the primary core and reused
+ * on secondary cores.
+ ******************************************************************************/
+static entry_point_info_t *rmm_ep_info;
+
+/*******************************************************************************
+ * Static function declaration.
+ ******************************************************************************/
+static int32_t rmm_init(void);
+
+/*******************************************************************************
+ * This function takes an RMM context pointer and performs a synchronous entry
+ * into it.
+ ******************************************************************************/
+uint64_t rmmd_rmm_sync_entry(rmmd_rmm_context_t *rmm_ctx)
+{
+	uint64_t rc;
+
+	assert(rmm_ctx != NULL);
+
+	cm_set_context(&(rmm_ctx->cpu_ctx), REALM);
+
+	/* Restore the realm context assigned above */
+	cm_el1_sysregs_context_restore(REALM);
+	cm_el2_sysregs_context_restore(REALM);
+	cm_set_next_eret_context(REALM);
+
+	/* Enter RMM */
+	rc = rmmd_rmm_enter(&rmm_ctx->c_rt_ctx);
+
+	/*
+	 * Save realm context. EL1 and EL2 Non-secure
+	 * contexts will be restored before exiting to
+	 * Non-secure world, therefore there is no need
+	 * to clear EL1 and EL2 context registers.
+	 */
+	cm_el1_sysregs_context_save(REALM);
+	cm_el2_sysregs_context_save(REALM);
+
+	return rc;
+}
+
+/*******************************************************************************
+ * This function returns to the place where rmmd_rmm_sync_entry() was
+ * called originally.
+ ******************************************************************************/
+__dead2 void rmmd_rmm_sync_exit(uint64_t rc)
+{
+	rmmd_rmm_context_t *ctx = &rmm_context[plat_my_core_pos()];
+
+	/* Get context of the RMM in use by this CPU. */
+	assert(cm_get_context(REALM) == &(ctx->cpu_ctx));
+
+	/*
+	 * The RMMD must have initiated the original request through a
+	 * synchronous entry into RMM. Jump back to the original C runtime
+	 * context with the value of rc in x0;
+	 */
+	rmmd_rmm_exit(ctx->c_rt_ctx, rc);
+
+	panic();
+}
+
+static void rmm_el2_context_init(el2_sysregs_t *regs)
+{
+	regs->ctx_regs[CTX_SPSR_EL2 >> 3] = REALM_SPSR_EL2;
+	regs->ctx_regs[CTX_SCTLR_EL2 >> 3] = SCTLR_EL2_RES1;
+}
+
+/*******************************************************************************
+ * Enable architecture extensions on first entry to Realm world.
+ ******************************************************************************/
+
+static void manage_extensions_realm(cpu_context_t *ctx)
+{
+	pmuv3_enable(ctx);
+
+	/*
+	 * Enable access to TPIDR2_EL0 if SME/SME2 is enabled for Non Secure world.
+	 */
+	if (is_feat_sme_supported()) {
+		sme_enable(ctx);
+	}
+}
+
+static void manage_extensions_realm_per_world(void)
+{
+	if (is_feat_sve_supported()) {
+	/*
+	 * Enable SVE and FPU in realm context when it is enabled for NS.
+	 * Realm manager must ensure that the SVE and FPU register
+	 * contexts are properly managed.
+	 */
+		sve_enable_per_world(&per_world_context[CPU_CONTEXT_REALM]);
+	}
+
+	/* NS can access this but Realm shouldn't */
+	if (is_feat_sys_reg_trace_supported()) {
+		sys_reg_trace_disable_per_world(&per_world_context[CPU_CONTEXT_REALM]);
+	}
+
+	/*
+	 * If SME/SME2 is supported and enabled for NS world, then disable trapping
+	 * of SME instructions for Realm world. RMM will save/restore required
+	 * registers that are shared with SVE/FPU so that Realm can use FPU or SVE.
+	 */
+	if (is_feat_sme_supported()) {
+		sme_enable_per_world(&per_world_context[CPU_CONTEXT_REALM]);
+	}
+}
+
+/*******************************************************************************
+ * Jump to the RMM for the first time.
+ ******************************************************************************/
+static int32_t rmm_init(void)
+{
+	long rc;
+	rmmd_rmm_context_t *ctx = &rmm_context[plat_my_core_pos()];
+
+	INFO("RMM init start.\n");
+
+	/* Enable architecture extensions */
+	manage_extensions_realm(&ctx->cpu_ctx);
+
+	manage_extensions_realm_per_world();
+
+	/* Initialize RMM EL2 context. */
+	rmm_el2_context_init(&ctx->cpu_ctx.el2_sysregs_ctx);
+
+	rc = rmmd_rmm_sync_entry(ctx);
+	if (rc != E_RMM_BOOT_SUCCESS) {
+		ERROR("RMM init failed: %ld\n", rc);
+		/* Mark the boot as failed for all the CPUs */
+		rmm_boot_failed = true;
+		return 0;
+	}
+
+	INFO("RMM init end.\n");
+
+	return 1;
+}
+
+/*******************************************************************************
+ * Load and read RMM manifest, setup RMM.
+ ******************************************************************************/
+int rmmd_setup(void)
+{
+	size_t shared_buf_size __unused;
+	uintptr_t shared_buf_base;
+	uint32_t ep_attr;
+	unsigned int linear_id = plat_my_core_pos();
+	rmmd_rmm_context_t *rmm_ctx = &rmm_context[linear_id];
+	struct rmm_manifest *manifest;
+	int rc;
+
+	/* Make sure RME is supported. */
+	assert(get_armv9_2_feat_rme_support() != 0U);
+
+	rmm_ep_info = bl31_plat_get_next_image_ep_info(REALM);
+	if (rmm_ep_info == NULL) {
+		WARN("No RMM image provided by BL2 boot loader, Booting "
+		     "device without RMM initialization. SMCs destined for "
+		     "RMM will return SMC_UNK\n");
+		return -ENOENT;
+	}
+
+	/* Under no circumstances will this parameter be 0 */
+	assert(rmm_ep_info->pc == RMM_BASE);
+
+	/* Initialise an entrypoint to set up the CPU context */
+	ep_attr = EP_REALM;
+	if ((read_sctlr_el3() & SCTLR_EE_BIT) != 0U) {
+		ep_attr |= EP_EE_BIG;
+	}
+
+	SET_PARAM_HEAD(rmm_ep_info, PARAM_EP, VERSION_1, ep_attr);
+	rmm_ep_info->spsr = SPSR_64(MODE_EL2,
+					MODE_SP_ELX,
+					DISABLE_ALL_EXCEPTIONS);
+
+	shared_buf_size =
+			plat_rmmd_get_el3_rmm_shared_mem(&shared_buf_base);
+
+	assert((shared_buf_size == SZ_4K) &&
+					((void *)shared_buf_base != NULL));
+
+	/* Load the boot manifest at the beginning of the shared area */
+	manifest = (struct rmm_manifest *)shared_buf_base;
+	rc = plat_rmmd_load_manifest(manifest);
+	if (rc != 0) {
+		ERROR("Error loading RMM Boot Manifest (%i)\n", rc);
+		return rc;
+	}
+	flush_dcache_range((uintptr_t)shared_buf_base, shared_buf_size);
+
+	/*
+	 * Prepare coldboot arguments for RMM:
+	 * arg0: This CPUID (primary processor).
+	 * arg1: Version for this Boot Interface.
+	 * arg2: PLATFORM_CORE_COUNT.
+	 * arg3: Base address for the EL3 <-> RMM shared area. The boot
+	 *       manifest will be stored at the beginning of this area.
+	 */
+	rmm_ep_info->args.arg0 = linear_id;
+	rmm_ep_info->args.arg1 = RMM_EL3_INTERFACE_VERSION;
+	rmm_ep_info->args.arg2 = PLATFORM_CORE_COUNT;
+	rmm_ep_info->args.arg3 = shared_buf_base;
+
+	/* Initialise RMM context with this entry point information */
+	cm_setup_context(&rmm_ctx->cpu_ctx, rmm_ep_info);
+
+	INFO("RMM setup done.\n");
+
+	/* Register init function for deferred init.  */
+	bl31_register_rmm_init(&rmm_init);
+
+	return 0;
+}
+
+/*******************************************************************************
+ * Forward SMC to the other security state
+ ******************************************************************************/
+static uint64_t	rmmd_smc_forward(uint32_t src_sec_state,
+				 uint32_t dst_sec_state, uint64_t x0,
+				 uint64_t x1, uint64_t x2, uint64_t x3,
+				 uint64_t x4, void *handle)
+{
+	cpu_context_t *ctx = cm_get_context(dst_sec_state);
+
+	/* Save incoming security state */
+	cm_el1_sysregs_context_save(src_sec_state);
+	cm_el2_sysregs_context_save(src_sec_state);
+
+	/* Restore outgoing security state */
+	cm_el1_sysregs_context_restore(dst_sec_state);
+	cm_el2_sysregs_context_restore(dst_sec_state);
+	cm_set_next_eret_context(dst_sec_state);
+
+	/*
+	 * As per SMCCCv1.2, we need to preserve x4 to x7 unless
+	 * being used as return args. Hence we differentiate the
+	 * onward and backward path. Support upto 8 args in the
+	 * onward path and 4 args in return path.
+	 * Register x4 will be preserved by RMM in case it is not
+	 * used in return path.
+	 */
+	if (src_sec_state == NON_SECURE) {
+		SMC_RET8(ctx, x0, x1, x2, x3, x4,
+			 SMC_GET_GP(handle, CTX_GPREG_X5),
+			 SMC_GET_GP(handle, CTX_GPREG_X6),
+			 SMC_GET_GP(handle, CTX_GPREG_X7));
+	}
+
+	SMC_RET5(ctx, x0, x1, x2, x3, x4);
+}
+
+/*******************************************************************************
+ * This function handles all SMCs in the range reserved for RMI. Each call is
+ * either forwarded to the other security state or handled by the RMM dispatcher
+ ******************************************************************************/
+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)
+{
+	uint32_t src_sec_state;
+
+	/* If RMM failed to boot, treat any RMI SMC as unknown */
+	if (rmm_boot_failed) {
+		WARN("RMMD: Failed to boot up RMM. Ignoring RMI call\n");
+		SMC_RET1(handle, SMC_UNK);
+	}
+
+	/* Determine which security state this SMC originated from */
+	src_sec_state = caller_sec_state(flags);
+
+	/* RMI must not be invoked by the Secure world */
+	if (src_sec_state == SMC_FROM_SECURE) {
+		WARN("RMMD: RMI invoked by secure world.\n");
+		SMC_RET1(handle, SMC_UNK);
+	}
+
+	/*
+	 * Forward an RMI call from the Normal world to the Realm world as it
+	 * is.
+	 */
+	if (src_sec_state == SMC_FROM_NON_SECURE) {
+		/*
+		 * If SVE hint bit is set in the flags then update the SMC
+		 * function id and pass it on to the lower EL.
+		 */
+		if (is_sve_hint_set(flags)) {
+			smc_fid |= (FUNCID_SVE_HINT_MASK <<
+				    FUNCID_SVE_HINT_SHIFT);
+		}
+		VERBOSE("RMMD: RMI call from non-secure world.\n");
+		return rmmd_smc_forward(NON_SECURE, REALM, smc_fid,
+					x1, x2, x3, x4, handle);
+	}
+
+	if (src_sec_state != SMC_FROM_REALM) {
+		SMC_RET1(handle, SMC_UNK);
+	}
+
+	switch (smc_fid) {
+	case RMM_RMI_REQ_COMPLETE: {
+		uint64_t x5 = SMC_GET_GP(handle, CTX_GPREG_X5);
+
+		return rmmd_smc_forward(REALM, NON_SECURE, x1,
+					x2, x3, x4, x5, handle);
+	}
+	default:
+		WARN("RMMD: Unsupported RMM call 0x%08x\n", smc_fid);
+		SMC_RET1(handle, SMC_UNK);
+	}
+}
+
+/*******************************************************************************
+ * This cpu has been turned on. Enter RMM to initialise R-EL2.  Entry into RMM
+ * is done after initialising minimal architectural state that guarantees safe
+ * execution.
+ ******************************************************************************/
+static void *rmmd_cpu_on_finish_handler(const void *arg)
+{
+	long rc;
+	uint32_t linear_id = plat_my_core_pos();
+	rmmd_rmm_context_t *ctx = &rmm_context[linear_id];
+
+	if (rmm_boot_failed) {
+		/* RMM Boot failed on a previous CPU. Abort. */
+		ERROR("RMM Failed to initialize. Ignoring for CPU%d\n",
+								linear_id);
+		return NULL;
+	}
+
+	/*
+	 * Prepare warmboot arguments for RMM:
+	 * arg0: This CPUID.
+	 * arg1 to arg3: Not used.
+	 */
+	rmm_ep_info->args.arg0 = linear_id;
+	rmm_ep_info->args.arg1 = 0ULL;
+	rmm_ep_info->args.arg2 = 0ULL;
+	rmm_ep_info->args.arg3 = 0ULL;
+
+	/* Initialise RMM context with this entry point information */
+	cm_setup_context(&ctx->cpu_ctx, rmm_ep_info);
+
+	/* Enable architecture extensions */
+	manage_extensions_realm(&ctx->cpu_ctx);
+
+	/* Initialize RMM EL2 context. */
+	rmm_el2_context_init(&ctx->cpu_ctx.el2_sysregs_ctx);
+
+	rc = rmmd_rmm_sync_entry(ctx);
+
+	if (rc != E_RMM_BOOT_SUCCESS) {
+		ERROR("RMM init failed on CPU%d: %ld\n", linear_id, rc);
+		/* Mark the boot as failed for any other booting CPU */
+		rmm_boot_failed = true;
+	}
+
+	return NULL;
+}
+
+/* Subscribe to PSCI CPU on to initialize RMM on secondary */
+SUBSCRIBE_TO_EVENT(psci_cpu_on_finish, rmmd_cpu_on_finish_handler);
+
+/* Convert GPT lib error to RMMD GTS error */
+static int gpt_to_gts_error(int error, uint32_t smc_fid, uint64_t address)
+{
+	int ret;
+
+	if (error == 0) {
+		return E_RMM_OK;
+	}
+
+	if (error == -EINVAL) {
+		ret = E_RMM_BAD_ADDR;
+	} else {
+		/* This is the only other error code we expect */
+		assert(error == -EPERM);
+		ret = E_RMM_BAD_PAS;
+	}
+
+	ERROR("RMMD: PAS Transition failed. GPT ret = %d, PA: 0x%"PRIx64 ", FID = 0x%x\n",
+				error, address, smc_fid);
+	return ret;
+}
+
+/*******************************************************************************
+ * This function handles RMM-EL3 interface SMCs
+ ******************************************************************************/
+uint64_t rmmd_rmm_el3_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2,
+				uint64_t x3, uint64_t x4, void *cookie,
+				void *handle, uint64_t flags)
+{
+	uint32_t src_sec_state;
+	int ret;
+
+	/* If RMM failed to boot, treat any RMM-EL3 interface SMC as unknown */
+	if (rmm_boot_failed) {
+		WARN("RMMD: Failed to boot up RMM. Ignoring RMM-EL3 call\n");
+		SMC_RET1(handle, SMC_UNK);
+	}
+
+	/* Determine which security state this SMC originated from */
+	src_sec_state = caller_sec_state(flags);
+
+	if (src_sec_state != SMC_FROM_REALM) {
+		WARN("RMMD: RMM-EL3 call originated from secure or normal world\n");
+		SMC_RET1(handle, SMC_UNK);
+	}
+
+	switch (smc_fid) {
+	case RMM_GTSI_DELEGATE:
+		ret = gpt_delegate_pas(x1, PAGE_SIZE_4KB, SMC_FROM_REALM);
+		SMC_RET1(handle, gpt_to_gts_error(ret, smc_fid, x1));
+	case RMM_GTSI_UNDELEGATE:
+		ret = gpt_undelegate_pas(x1, PAGE_SIZE_4KB, SMC_FROM_REALM);
+		SMC_RET1(handle, gpt_to_gts_error(ret, smc_fid, x1));
+	case RMM_ATTEST_GET_PLAT_TOKEN:
+		ret = rmmd_attest_get_platform_token(x1, &x2, x3);
+		SMC_RET2(handle, ret, x2);
+	case RMM_ATTEST_GET_REALM_KEY:
+		ret = rmmd_attest_get_signing_key(x1, &x2, x3);
+		SMC_RET2(handle, ret, x2);
+
+	case RMM_BOOT_COMPLETE:
+		VERBOSE("RMMD: running rmmd_rmm_sync_exit\n");
+		rmmd_rmm_sync_exit(x1);
+
+	default:
+		WARN("RMMD: Unsupported RMM-EL3 call 0x%08x\n", smc_fid);
+		SMC_RET1(handle, SMC_UNK);
+	}
+}
diff --git a/services/std_svc/rmmd/rmmd_private.h b/services/std_svc/rmmd/rmmd_private.h
new file mode 100644
index 0000000..4954a43
--- /dev/null
+++ b/services/std_svc/rmmd/rmmd_private.h
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2021-2022, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef RMMD_PRIVATE_H
+#define RMMD_PRIVATE_H
+
+#include <context.h>
+
+/*******************************************************************************
+ * Constants that allow assembler code to preserve callee-saved registers of the
+ * C runtime context while performing a security state switch.
+ ******************************************************************************/
+#define RMMD_C_RT_CTX_X19		0x0
+#define RMMD_C_RT_CTX_X20		0x8
+#define RMMD_C_RT_CTX_X21		0x10
+#define RMMD_C_RT_CTX_X22		0x18
+#define RMMD_C_RT_CTX_X23		0x20
+#define RMMD_C_RT_CTX_X24		0x28
+#define RMMD_C_RT_CTX_X25		0x30
+#define RMMD_C_RT_CTX_X26		0x38
+#define RMMD_C_RT_CTX_X27		0x40
+#define RMMD_C_RT_CTX_X28		0x48
+#define RMMD_C_RT_CTX_X29		0x50
+#define RMMD_C_RT_CTX_X30		0x58
+
+#define RMMD_C_RT_CTX_SIZE		0x60
+#define RMMD_C_RT_CTX_ENTRIES		(RMMD_C_RT_CTX_SIZE >> DWORD_SHIFT)
+
+#ifndef __ASSEMBLER__
+#include <stdint.h>
+
+/*
+ * Data structure used by the RMM dispatcher (RMMD) in EL3 to track context of
+ * the RMM at R-EL2.
+ */
+typedef struct rmmd_rmm_context {
+	uint64_t c_rt_ctx;
+	cpu_context_t cpu_ctx;
+} rmmd_rmm_context_t;
+
+/* Functions used to enter/exit the RMM synchronously */
+uint64_t rmmd_rmm_sync_entry(rmmd_rmm_context_t *ctx);
+__dead2 void rmmd_rmm_sync_exit(uint64_t rc);
+
+/* Functions implementing attestation utilities for RMM */
+int rmmd_attest_get_platform_token(uint64_t buf_pa, uint64_t *buf_size,
+				   uint64_t c_size);
+int rmmd_attest_get_signing_key(uint64_t buf_pa, uint64_t *buf_size,
+				uint64_t ecc_curve);
+
+/* Assembly helpers */
+uint64_t rmmd_rmm_enter(uint64_t *c_rt_ctx);
+void __dead2 rmmd_rmm_exit(uint64_t c_rt_ctx, uint64_t ret);
+
+/* Reference to PM ops for the RMMD */
+extern const spd_pm_ops_t rmmd_pm;
+
+#endif /* __ASSEMBLER__ */
+
+#endif /* RMMD_PRIVATE_H */
diff --git a/services/std_svc/rmmd/trp/linker.ld.S b/services/std_svc/rmmd/trp/linker.ld.S
new file mode 100644
index 0000000..9895cf9
--- /dev/null
+++ b/services/std_svc/rmmd/trp/linker.ld.S
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2021-2023, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <common/bl_common.ld.h>
+#include <lib/xlat_tables/xlat_tables_defs.h>
+
+/* Mapped using 4K pages, requires us to align different sections with
+ * different property at the same granularity. */
+PAGE_SIZE_4K = 4096;
+
+OUTPUT_FORMAT("elf64-littleaarch64")
+OUTPUT_ARCH(aarch64)
+ENTRY(trp_head)
+
+MEMORY {
+	RAM (rwx): ORIGIN = RMM_BASE, LENGTH = RMM_LIMIT - RMM_BASE
+}
+
+
+SECTIONS
+{
+	. = RMM_BASE;
+
+	.text : {
+		*(.head.text)
+		. = ALIGN(8);
+		*(.text*)
+	} >RAM
+
+	. = ALIGN(PAGE_SIZE_4K);
+
+	.rodata : {
+		*(.rodata*)
+	} >RAM
+
+	. = ALIGN(PAGE_SIZE_4K);
+
+	 __RW_START__ = . ;
+
+	.data : {
+		*(.data*)
+	} >RAM
+
+	.bss (NOLOAD) : {
+		__BSS_START__ = .;
+		*(.bss*)
+		__BSS_END__ = .;
+	} >RAM
+	__BSS_SIZE__ = SIZEOF(.bss);
+
+
+	STACK_SECTION >RAM
+
+
+	/*
+	* Define a linker symbol to mark the end of the RW memory area for this
+	* image.
+	*/
+	__RW_END__ = .;
+	__RMM_END__ = .;
+
+
+	/DISCARD/ : { *(.dynstr*) }
+	/DISCARD/ : { *(.dynamic*) }
+	/DISCARD/ : { *(.plt*) }
+	/DISCARD/ : { *(.interp*) }
+	/DISCARD/ : { *(.gnu*) }
+	/DISCARD/ : { *(.note*) }
+}
diff --git a/services/std_svc/rmmd/trp/trp.mk b/services/std_svc/rmmd/trp/trp.mk
new file mode 100644
index 0000000..b7bd317
--- /dev/null
+++ b/services/std_svc/rmmd/trp/trp.mk
@@ -0,0 +1,27 @@
+#
+# Copyright (c) 2021-2023 Arm Limited and Contributors. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
+RMM_SOURCES		+=	services/std_svc/rmmd/trp/trp_entry.S \
+				services/std_svc/rmmd/trp/trp_main.c  \
+				services/std_svc/rmmd/trp/trp_helpers.c
+
+RMM_DEFAULT_LINKER_SCRIPT_SOURCE := services/std_svc/rmmd/trp/linker.ld.S
+
+ifneq ($(findstring gcc,$(notdir $(LD))),)
+        RMM_LDFLAGS	+=	-Wl,--sort-section=alignment
+else ifneq ($(findstring ld,$(notdir $(LD))),)
+        RMM_LDFLAGS	+=	--sort-section=alignment
+endif
+
+# Include the platform-specific TRP Makefile
+# If no platform-specific TRP Makefile exists, it means TRP is not supported
+# on this platform.
+TRP_PLAT_MAKEFILE := $(wildcard ${PLAT_DIR}/trp/trp-${PLAT}.mk)
+ifeq (,${TRP_PLAT_MAKEFILE})
+  $(error TRP is not supported on platform ${PLAT})
+else
+  include ${TRP_PLAT_MAKEFILE}
+endif
diff --git a/services/std_svc/rmmd/trp/trp_entry.S b/services/std_svc/rmmd/trp/trp_entry.S
new file mode 100644
index 0000000..3e1d8c9
--- /dev/null
+++ b/services/std_svc/rmmd/trp/trp_entry.S
@@ -0,0 +1,153 @@
+/*
+ * Copyright (c) 2021-2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <asm_macros.S>
+#include <services/rmmd_svc.h>
+
+#include <platform_def.h>
+#include "trp_private.h"
+
+.global trp_head
+.global trp_smc
+
+.section ".head.text", "ax"
+
+	/* ---------------------------------------------
+	 * Populate the params in x0-x7 from the pointer
+	 * to the smc args structure in x0.
+	 * ---------------------------------------------
+	 */
+	.macro restore_args_call_smc
+	ldp	x6, x7, [x0, #TRP_ARG6]
+	ldp	x4, x5, [x0, #TRP_ARG4]
+	ldp	x2, x3, [x0, #TRP_ARG2]
+	ldp	x0, x1, [x0, #TRP_ARG0]
+	smc	#0
+	.endm
+
+	/* ---------------------------------------------
+	 * Entry point for TRP
+	 * ---------------------------------------------
+	 */
+trp_head:
+	/*
+	 * Stash arguments from previous boot stage
+	 */
+	mov	x20, x0
+	mov	x21, x1
+	mov	x22, x2
+	mov	x23, x3
+
+	/*
+	 * Validate CPUId before allocating a stack.
+	 */
+	cmp	x20, #PLATFORM_CORE_COUNT
+	b.lo	1f
+
+	mov_imm	x0, RMM_BOOT_COMPLETE
+	mov_imm	x1, E_RMM_BOOT_CPU_ID_OUT_OF_RANGE
+	smc	#0
+
+	/* EL3 should never return back here, so panic if it does */
+	b	trp_panic
+
+1:
+	bl	plat_set_my_stack
+
+	/*
+	 * Find out whether this is a cold or warm boot
+	 */
+	ldr	x1, cold_boot_flag
+	cbz	x1, warm_boot
+
+	/*
+	 * Update cold boot flag to indicate cold boot is done
+	 */
+	adr	x2, cold_boot_flag
+	str	xzr, [x2]
+
+	/* ---------------------------------------------
+	 * Zero out BSS section
+	 * ---------------------------------------------
+	 */
+	ldr	x0, =__BSS_START__
+	ldr	x1, =__BSS_SIZE__
+	bl	zeromem
+
+	mov	x0, x20
+	mov	x1, x21
+	mov	x2, x22
+	mov	x3, x23
+	bl	trp_setup
+	bl	trp_main
+	b	1f
+
+warm_boot:
+	mov	x0, x20
+	mov	x1, x21
+	mov	x2, x22
+	mov	x3, x23
+	bl	trp_validate_warmboot_args
+	cbnz	x0, trp_panic /* Failed to validate warmboot args */
+
+1:
+	mov_imm	x0, RMM_BOOT_COMPLETE
+	mov	x1, xzr /* RMM_BOOT_SUCCESS */
+	smc	#0
+	b	trp_handler
+
+trp_panic:
+	no_ret plat_panic_handler
+
+	/*
+	 * Flag to mark if it is a cold boot.
+	 * 1: cold boot, 0: warmboot.
+	 */
+.align 3
+cold_boot_flag:
+	.dword		1
+
+	/* ---------------------------------------------
+	 *   Direct SMC call to BL31 service provided by
+	 *   RMM Dispatcher
+	 * ---------------------------------------------
+	 */
+func trp_smc
+	restore_args_call_smc
+	ret
+endfunc trp_smc
+
+	/* ---------------------------------------------
+	 * RMI call handler
+	 * ---------------------------------------------
+	 */
+func trp_handler
+	/*
+	 * Save Link Register and X4, as per SMCCC v1.2 its value
+	 * must be preserved unless it contains result, as specified
+	 * in the function definition.
+	 */
+	stp	x4, lr, [sp, #-16]!
+
+	/*
+	 * Zero the space for X0-X3 in trp_smc_result structure
+	 * and pass its address as the last argument.
+	 */
+	stp	xzr, xzr, [sp, #-16]!
+	stp	xzr, xzr, [sp, #-16]!
+	mov	x7, sp
+
+	bl	trp_rmi_handler
+
+	ldp	x1, x2, [sp], #16
+	ldp	x3, x4, [sp], #16
+	ldp	x5, lr, [sp], #16
+
+	ldr	x0, =RMM_RMI_REQ_COMPLETE
+	smc	#0
+
+	b	trp_handler
+endfunc trp_handler
diff --git a/services/std_svc/rmmd/trp/trp_helpers.c b/services/std_svc/rmmd/trp/trp_helpers.c
new file mode 100644
index 0000000..159f3a5
--- /dev/null
+++ b/services/std_svc/rmmd/trp/trp_helpers.c
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+
+#include <plat/common/platform.h>
+#include <services/rmmd_svc.h>
+#include "trp_private.h"
+
+/*
+ * Per cpu data structure to populate parameters for an SMC in C code and use
+ * a pointer to this structure in assembler code to populate x0-x7
+ */
+static trp_args_t trp_smc_args[PLATFORM_CORE_COUNT];
+
+/*
+ * Set the arguments for SMC call
+ */
+trp_args_t *set_smc_args(uint64_t arg0,
+			uint64_t arg1,
+			uint64_t arg2,
+			uint64_t arg3,
+			uint64_t arg4,
+			uint64_t arg5,
+			uint64_t arg6,
+			uint64_t arg7)
+{
+	uint32_t linear_id;
+	trp_args_t *pcpu_smc_args;
+
+	/*
+	 * Return to Secure Monitor by raising an SMC. The results of the
+	 * service are passed as an arguments to the SMC
+	 */
+	linear_id = plat_my_core_pos();
+	pcpu_smc_args = &trp_smc_args[linear_id];
+	write_trp_arg(pcpu_smc_args, TRP_ARG0, arg0);
+	write_trp_arg(pcpu_smc_args, TRP_ARG1, arg1);
+	write_trp_arg(pcpu_smc_args, TRP_ARG2, arg2);
+	write_trp_arg(pcpu_smc_args, TRP_ARG3, arg3);
+	write_trp_arg(pcpu_smc_args, TRP_ARG4, arg4);
+	write_trp_arg(pcpu_smc_args, TRP_ARG5, arg5);
+	write_trp_arg(pcpu_smc_args, TRP_ARG6, arg6);
+	write_trp_arg(pcpu_smc_args, TRP_ARG7, arg7);
+
+	return pcpu_smc_args;
+}
+
+/*
+ * Abort the boot process with the reason given in err.
+ */
+__dead2 void trp_boot_abort(uint64_t err)
+{
+	(void)trp_smc(set_smc_args(RMM_BOOT_COMPLETE, err, 0, 0, 0, 0, 0, 0));
+	panic();
+}
diff --git a/services/std_svc/rmmd/trp/trp_main.c b/services/std_svc/rmmd/trp/trp_main.c
new file mode 100644
index 0000000..33f2fb0
--- /dev/null
+++ b/services/std_svc/rmmd/trp/trp_main.c
@@ -0,0 +1,185 @@
+/*
+ * Copyright (c) 2021-2022, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <common/debug.h>
+#include <plat/common/platform.h>
+#include <services/rmm_core_manifest.h>
+#include <services/rmmd_svc.h>
+#include <services/trp/platform_trp.h>
+#include <trp_helpers.h>
+#include "trp_private.h"
+
+#include <platform_def.h>
+
+/* Parameters received from the previous image */
+static unsigned int trp_boot_abi_version;
+static uintptr_t trp_shared_region_start;
+
+/* Parameters received from boot manifest */
+uint32_t trp_boot_manifest_version;
+
+/*******************************************************************************
+ * Setup function for TRP.
+ ******************************************************************************/
+void trp_setup(uint64_t x0,
+	       uint64_t x1,
+	       uint64_t x2,
+	       uint64_t x3)
+{
+	/*
+	 * Validate boot parameters
+	 *
+	 * According to the Boot Interface ABI v.0.1,
+	 * the parameters received from EL3 are:
+	 * x0: CPUID (verified earlier, so not used)
+	 * x1: Boot Interface version
+	 * x2: PLATFORM_CORE_COUNT
+	 * x3: Pointer to the shared memory area.
+	 */
+
+	(void)x0;
+
+	if (TRP_RMM_EL3_VERSION_GET_MAJOR(x1) != TRP_RMM_EL3_ABI_VERS_MAJOR) {
+		trp_boot_abort(E_RMM_BOOT_VERSION_MISMATCH);
+	}
+
+	if ((void *)x3 == NULL) {
+		trp_boot_abort(E_RMM_BOOT_INVALID_SHARED_BUFFER);
+	}
+
+	if (x2 > TRP_PLATFORM_CORE_COUNT) {
+		trp_boot_abort(E_RMM_BOOT_CPUS_OUT_OF_RANGE);
+	}
+
+	trp_boot_abi_version = x1;
+	trp_shared_region_start = x3;
+	flush_dcache_range((uintptr_t)&trp_boot_abi_version,
+			   sizeof(trp_boot_abi_version));
+	flush_dcache_range((uintptr_t)&trp_shared_region_start,
+			   sizeof(trp_shared_region_start));
+
+	/* Perform early platform-specific setup */
+	trp_early_platform_setup((struct rmm_manifest *)trp_shared_region_start);
+}
+
+int trp_validate_warmboot_args(uint64_t x0, uint64_t x1,
+			       uint64_t x2, uint64_t x3)
+{
+	/*
+	 * Validate boot parameters for warm boot
+	 *
+	 * According to the Boot Interface ABI v.0.1, the parameters
+	 * received from EL3 during warm boot are:
+	 *
+	 * x0: CPUID (verified earlier so not used here)
+	 * [x1:x3]: RES0
+	 */
+
+	(void)x0;
+
+	return ((x1 | x2 | x3) == 0UL) ? 0 : E_RMM_BOOT_UNKNOWN;
+}
+
+/* Main function for TRP */
+void trp_main(void)
+{
+	NOTICE("TRP: %s\n", version_string);
+	NOTICE("TRP: %s\n", build_message);
+	NOTICE("TRP: Supported RMM-EL3 Interface ABI: v.%u.%u\n",
+		TRP_RMM_EL3_ABI_VERS_MAJOR, TRP_RMM_EL3_ABI_VERS_MINOR);
+	NOTICE("TRP: Boot Manifest Version: v.%u.%u\n",
+		RMMD_GET_MANIFEST_VERSION_MAJOR(trp_boot_manifest_version),
+		RMMD_GET_MANIFEST_VERSION_MINOR(trp_boot_manifest_version));
+	INFO("TRP: Memory base: 0x%lx\n", (unsigned long)RMM_BASE);
+	INFO("TRP: Shared region base address: 0x%lx\n",
+			(unsigned long)trp_shared_region_start);
+	INFO("TRP: Total size: 0x%lx bytes\n",
+			(unsigned long)(RMM_END - RMM_BASE));
+	INFO("TRP: RMM-EL3 Interface ABI reported by EL3: v.%u.%u\n",
+		TRP_RMM_EL3_VERSION_GET_MAJOR(trp_boot_abi_version),
+		TRP_RMM_EL3_VERSION_GET_MINOR(trp_boot_abi_version));
+}
+
+/*******************************************************************************
+ * Returning RMI version back to Normal World
+ ******************************************************************************/
+static void trp_ret_rmi_version(unsigned long long rmi_version,
+				struct trp_smc_result *smc_ret)
+{
+	if (rmi_version != RMI_ABI_VERSION) {
+		smc_ret->x[0] = RMI_ERROR_INPUT;
+	} else {
+		smc_ret->x[0] = RMI_SUCCESS;
+	}
+	VERBOSE("RMM version is %u.%u\n", RMI_ABI_VERSION_MAJOR,
+					  RMI_ABI_VERSION_MINOR);
+	smc_ret->x[1] = RMI_ABI_VERSION;
+	smc_ret->x[2] = RMI_ABI_VERSION;
+}
+
+/*******************************************************************************
+ * Transitioning granule of NON-SECURE type to REALM type
+ ******************************************************************************/
+static void trp_asc_mark_realm(unsigned long long x1,
+				struct trp_smc_result *smc_ret)
+{
+	VERBOSE("Delegating granule 0x%llx\n", x1);
+	smc_ret->x[0] = trp_smc(set_smc_args(RMM_GTSI_DELEGATE, x1,
+						0UL, 0UL, 0UL, 0UL, 0UL, 0UL));
+
+	if (smc_ret->x[0] != 0ULL) {
+		ERROR("Granule transition from NON-SECURE type to REALM type "
+			"failed 0x%llx\n", smc_ret->x[0]);
+	}
+}
+
+/*******************************************************************************
+ * Transitioning granule of REALM type to NON-SECURE type
+ ******************************************************************************/
+static void trp_asc_mark_nonsecure(unsigned long long x1,
+				   struct trp_smc_result *smc_ret)
+{
+	VERBOSE("Undelegating granule 0x%llx\n", x1);
+	smc_ret->x[0] = trp_smc(set_smc_args(RMM_GTSI_UNDELEGATE, x1,
+						0UL, 0UL, 0UL, 0UL, 0UL, 0UL));
+
+	if (smc_ret->x[0] != 0ULL) {
+		ERROR("Granule transition from REALM type to NON-SECURE type "
+			"failed 0x%llx\n", smc_ret->x[0]);
+	}
+}
+
+/*******************************************************************************
+ * Main RMI SMC handler function
+ ******************************************************************************/
+void trp_rmi_handler(unsigned long fid,
+		     unsigned long long x1, unsigned long long x2,
+		     unsigned long long x3, unsigned long long x4,
+		     unsigned long long x5, unsigned long long x6,
+		     struct trp_smc_result *smc_ret)
+{
+	/* Not used in the current implementation */
+	(void)x2;
+	(void)x3;
+	(void)x4;
+	(void)x5;
+	(void)x6;
+
+	switch (fid) {
+	case RMI_RMM_REQ_VERSION:
+		trp_ret_rmi_version(x1, smc_ret);
+		break;
+	case RMI_RMM_GRANULE_DELEGATE:
+		trp_asc_mark_realm(x1, smc_ret);
+		break;
+	case RMI_RMM_GRANULE_UNDELEGATE:
+		trp_asc_mark_nonsecure(x1, smc_ret);
+		break;
+	default:
+		ERROR("Invalid SMC code to %s, FID %lx\n", __func__, fid);
+		smc_ret->x[0] = SMC_UNK;
+	}
+}
diff --git a/services/std_svc/rmmd/trp/trp_private.h b/services/std_svc/rmmd/trp/trp_private.h
new file mode 100644
index 0000000..d8c6960
--- /dev/null
+++ b/services/std_svc/rmmd/trp/trp_private.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2021-2022, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef TRP_PRIVATE_H
+#define TRP_PRIVATE_H
+
+#include <services/rmmd_svc.h>
+#include <trp_helpers.h>
+
+/* Definitions for RMM-EL3 Interface ABI VERSION */
+#define TRP_RMM_EL3_ABI_VERS_MAJOR	RMM_EL3_IFC_VERSION_MAJOR
+#define TRP_RMM_EL3_ABI_VERS_MINOR	RMM_EL3_IFC_VERSION_MINOR
+#define TRP_RMM_EL3_ABI_VERS	(((TRP_RMM_EL3_ABI_VERS_MAJOR & 0x7FFF) << 16) | \
+				 (TRP_RMM_EL3_ABI_VERS_MINOR & 0xFFFF))
+
+#define TRP_PLATFORM_CORE_COUNT		PLATFORM_CORE_COUNT
+
+#ifndef __ASSEMBLER__
+
+#include <stdint.h>
+
+#define write_trp_arg(args, offset, val) (((args)->regs[offset >> 3])	\
+					 = val)
+/* RMI SMC64 FIDs handled by the TRP */
+#define RMI_RMM_REQ_VERSION		SMC64_RMI_FID(U(0))
+#define RMI_RMM_GRANULE_DELEGATE	SMC64_RMI_FID(U(1))
+#define RMI_RMM_GRANULE_UNDELEGATE	SMC64_RMI_FID(U(2))
+
+/* Definitions for RMI VERSION */
+#define RMI_ABI_VERSION_MAJOR		U(0x0)
+#define RMI_ABI_VERSION_MINOR		U(0x0)
+#define RMI_ABI_VERSION			(((RMI_ABI_VERSION_MAJOR & 0x7FFF) \
+								  << 16) | \
+					 (RMI_ABI_VERSION_MINOR & 0xFFFF))
+
+#define TRP_RMM_EL3_VERSION_GET_MAJOR(x)		\
+				RMM_EL3_IFC_VERSION_GET_MAJOR((x))
+#define TRP_RMM_EL3_VERSION_GET_MINOR(x)		\
+				RMM_EL3_IFC_VERSION_GET_MAJOR_MINOR((x))
+
+/* Helper to issue SMC calls to BL31 */
+uint64_t trp_smc(trp_args_t *);
+
+/* The main function to executed only by Primary CPU */
+void trp_main(void);
+
+/* Setup TRP. Executed only by Primary CPU */
+void trp_setup(uint64_t x0,
+	       uint64_t x1,
+	       uint64_t x2,
+	       uint64_t x3);
+
+/* Validate arguments for warm boot only */
+int trp_validate_warmboot_args(uint64_t x0, uint64_t x1,
+			       uint64_t x2, uint64_t x3);
+
+#endif /* __ASSEMBLER__ */
+#endif /* TRP_PRIVATE_H */