diff --git a/docs/components/rmm-el3-comms-spec.rst b/docs/components/rmm-el3-comms-spec.rst
index 9140d54..b767958 100644
--- a/docs/components/rmm-el3-comms-spec.rst
+++ b/docs/components/rmm-el3-comms-spec.rst
@@ -200,7 +200,7 @@
 
 .. _runtime_services_and_interface:
 
-RMMM-EL3 Runtime Interface
+RMM-EL3 Runtime Interface
 __________________________
 
 This section defines the RMM-EL3 runtime interface which specifies the ABI for
@@ -247,9 +247,133 @@
    :header: "FID", "Command"
    :widths: 2 5
 
+   0xC400018F,``RMM_RMI_REQ_COMPLETE``
+   0xC40001B0,``RMM_GTSI_DELEGATE``
+   0xC40001B1,``RMM_GTSI_UNDELEGATE``
    0xC40001B2,``RMM_ATTEST_GET_REALM_KEY``
    0xC40001B3,``RMM_ATTEST_GET_PLAT_TOKEN``
 
+RMM_RMI_REQ_COMPLETE command
+============================
+
+Notifies the completion of an RMI call to the Non-Secure world.
+
+This call is the only function currently in RMM-EL3 runtime interface which
+results in a world switch to NS. This call is the reply to the original RMI
+call and it is forwarded by EL3 to the NS world.
+
+FID
+---
+
+``0xC400018F``
+
+Input values
+------------
+
+.. csv-table::
+   :header: "Name", "Register", "Field", "Type", "Description"
+   :widths: 1 1 1 1 5
+
+   fid,x0,[63:0],UInt64,Command FID
+   err_code,x1,[63:0],RmiCommandReturnCode,Error code returned by the RMI service invoked by NS World. See Realm Management Monitor specification for more info
+
+Output values
+-------------
+
+This call does not return.
+
+Failure conditions
+------------------
+
+Since this call does not return to RMM, there is no failure condition which
+can be notified back to RMM.
+
+RMM_GTSI_DELEGATE command
+=========================
+
+Delegate a memory granule by changing its PAS from Non-Secure to Realm.
+
+FID
+---
+
+``0xC40001B0``
+
+Input values
+------------
+
+.. csv-table::
+   :header: "Name", "Register", "Field", "Type", "Description"
+   :widths: 1 1 1 1 5
+
+   fid,x0,[63:0],UInt64,Command FID
+   base_pa,x1,[63:0],Address,PA of the start of the granule to be delegated
+
+Output values
+-------------
+
+.. csv-table::
+   :header: "Name", "Register", "Field", "Type", "Description"
+   :widths: 1 1 1 2 4
+
+   Result,x0,[63:0],Error Code,Command return status
+
+Failure conditions
+------------------
+
+The table below shows all the possible error codes returned in ``Result`` upon
+a failure. The errors are ordered by condition check.
+
+.. csv-table::
+   :header: "ID", "Condition"
+   :widths: 1 5
+
+   ``E_RMM_BAD_ADDR``,``PA`` does not correspond to a valid granule address
+   ``E_RMM_BAD_PAS``,The granule pointed by ``PA`` does not belong to Non-Secure PAS
+   ``E_RMM_OK``,No errors detected
+
+RMM_GTSI_UNDELEGATE command
+===========================
+
+Undelegate a memory granule by changing its PAS from Realm to Non-Secure.
+
+FID
+---
+
+``0xC40001B1``
+
+Input values
+------------
+
+.. csv-table::
+   :header: "Name", "Register", "Field", "Type", "Description"
+   :widths: 1 1 1 1 5
+
+   fid,x0,[63:0],UInt64,Command FID
+   base_pa,x1,[63:0],Address,PA of the start of the granule to be undelegated
+
+Output values
+-------------
+
+.. csv-table::
+   :header: "Name", "Register", "Field", "Type", "Description"
+   :widths: 1 1 1 2 4
+
+   Result,x0,[63:0],Error Code,Command return status
+
+Failure conditions
+------------------
+
+The table below shows all the possible error codes returned in ``Result`` upon
+a failure. The errors are ordered by condition check.
+
+.. csv-table::
+   :header: "ID", "Condition"
+   :widths: 1 5
+
+   ``E_RMM_BAD_ADDR``,``PA`` does not correspond to a valid granule address
+   ``E_RMM_BAD_PAS``,The granule pointed by ``PA`` does not belong to Realm PAS
+   ``E_RMM_OK``,No errors detected
+
 RMM_ATTEST_GET_REALM_KEY command
 ================================
 
diff --git a/include/services/rmmd_svc.h b/include/services/rmmd_svc.h
index 6adc5f3..de7181c 100644
--- a/include/services/rmmd_svc.h
+++ b/include/services/rmmd_svc.h
@@ -38,7 +38,7 @@
  * RMM.
  */
 					/* 0x18F */
-#define RMMD_RMI_REQ_COMPLETE		SMC64_RMI_FID(U(0x3F))
+#define RMM_RMI_REQ_COMPLETE		SMC64_RMI_FID(U(0x3F))
 
 /* RMM_BOOT_COMPLETE arg0 error codes */
 #define E_RMM_BOOT_SUCCESS				(0)
@@ -80,8 +80,8 @@
 	((_fid & 0x00FE0000) == 0U)); })
 
 					/* 0x1B0 - 0x1B1 */
-#define RMMD_GTSI_DELEGATE		SMC64_RMMD_EL3_FID(U(0))
-#define RMMD_GTSI_UNDELEGATE		SMC64_RMMD_EL3_FID(U(1))
+#define RMM_GTSI_DELEGATE		SMC64_RMMD_EL3_FID(U(0))
+#define RMM_GTSI_UNDELEGATE		SMC64_RMMD_EL3_FID(U(1))
 
 /* Return error codes from RMM-EL3 SMCs */
 #define E_RMM_OK			 0
@@ -110,7 +110,7 @@
  *    ret1 - Size of the realm attestation key if successful.
  */
 					/* 0x1B2 */
-#define RMMD_ATTEST_GET_REALM_KEY	SMC64_RMMD_EL3_FID(U(2))
+#define RMM_ATTEST_GET_REALM_KEY	SMC64_RMMD_EL3_FID(U(2))
 
 /*
  * Retrieve Platform token from EL3.
@@ -126,7 +126,7 @@
  *    ret1 - Size of the platform token if successful.
  */
 					/* 0x1B3 */
-#define RMMD_ATTEST_GET_PLAT_TOKEN	SMC64_RMMD_EL3_FID(U(3))
+#define RMM_ATTEST_GET_PLAT_TOKEN	SMC64_RMMD_EL3_FID(U(3))
 
 /* ECC Curve types for attest key generation */
 #define ATTEST_KEY_CURVE_ECC_SECP384R1		0
diff --git a/lib/gpt_rme/gpt_rme.c b/lib/gpt_rme/gpt_rme.c
index d6fbc04..e001e5f 100644
--- a/lib/gpt_rme/gpt_rme.c
+++ b/lib/gpt_rme/gpt_rme.c
@@ -1076,7 +1076,7 @@
 		VERBOSE("      Caller: %u, Current GPI: %u\n", src_sec_state,
 			gpi_info.gpi);
 		spin_unlock(&gpt_lock);
-		return -EINVAL;
+		return -EPERM;
 	}
 
 	if (src_sec_state == SMC_FROM_SECURE) {
@@ -1197,7 +1197,7 @@
 		VERBOSE("      Caller: %u, Current GPI: %u\n", src_sec_state,
 			gpi_info.gpi);
 		spin_unlock(&gpt_lock);
-		return -EINVAL;
+		return -EPERM;
 	}
 
 
diff --git a/services/std_svc/rmmd/rmmd_main.c b/services/std_svc/rmmd/rmmd_main.c
index 322d9f2..7cb76de 100644
--- a/services/std_svc/rmmd/rmmd_main.c
+++ b/services/std_svc/rmmd/rmmd_main.c
@@ -311,7 +311,7 @@
 	}
 
 	switch (smc_fid) {
-	case RMMD_RMI_REQ_COMPLETE:
+	case RMM_RMI_REQ_COMPLETE:
 		return rmmd_smc_forward(REALM, NON_SECURE, x1,
 					x2, x3, x4, 0, handle);
 
@@ -419,16 +419,16 @@
 	}
 
 	switch (smc_fid) {
-	case RMMD_GTSI_DELEGATE:
+	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 RMMD_GTSI_UNDELEGATE:
+	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 RMMD_ATTEST_GET_PLAT_TOKEN:
+	case RMM_ATTEST_GET_PLAT_TOKEN:
 		ret = rmmd_attest_get_platform_token(x1, &x2, x3);
 		SMC_RET2(handle, ret, x2);
-	case RMMD_ATTEST_GET_REALM_KEY:
+	case RMM_ATTEST_GET_REALM_KEY:
 		ret = rmmd_attest_get_signing_key(x1, &x2, x3);
 		SMC_RET2(handle, ret, x2);
 
diff --git a/services/std_svc/rmmd/trp/trp_main.c b/services/std_svc/rmmd/trp/trp_main.c
index cf6ec7b..5a56af0 100644
--- a/services/std_svc/rmmd/trp/trp_main.c
+++ b/services/std_svc/rmmd/trp/trp_main.c
@@ -93,7 +93,7 @@
 {
 	VERBOSE("RMM version is %u.%u\n", RMI_ABI_VERSION_MAJOR,
 					  RMI_ABI_VERSION_MINOR);
-	return set_smc_args(RMMD_RMI_REQ_COMPLETE, RMI_ABI_VERSION,
+	return set_smc_args(RMM_RMI_REQ_COMPLETE, RMI_ABI_VERSION,
 			    0, 0, 0, 0, 0, 0);
 }
 
@@ -105,13 +105,13 @@
 	unsigned long long ret;
 
 	VERBOSE("Delegating granule 0x%llx\n", x1);
-	ret = trp_smc(set_smc_args(RMMD_GTSI_DELEGATE, x1, 0, 0, 0, 0, 0, 0));
+	ret = trp_smc(set_smc_args(RMM_GTSI_DELEGATE, x1, 0, 0, 0, 0, 0, 0));
 
 	if (ret != 0ULL) {
 		ERROR("Granule transition from NON-SECURE type to REALM type "
 			"failed 0x%llx\n", ret);
 	}
-	return set_smc_args(RMMD_RMI_REQ_COMPLETE, ret, 0, 0, 0, 0, 0, 0);
+	return set_smc_args(RMM_RMI_REQ_COMPLETE, ret, 0, 0, 0, 0, 0, 0);
 }
 
 /*******************************************************************************
@@ -122,13 +122,13 @@
 	unsigned long long ret;
 
 	VERBOSE("Undelegating granule 0x%llx\n", x1);
-	ret = trp_smc(set_smc_args(RMMD_GTSI_UNDELEGATE, x1, 0, 0, 0, 0, 0, 0));
+	ret = trp_smc(set_smc_args(RMM_GTSI_UNDELEGATE, x1, 0, 0, 0, 0, 0, 0));
 
 	if (ret != 0ULL) {
 		ERROR("Granule transition from REALM type to NON-SECURE type "
 			"failed 0x%llx\n", ret);
 	}
-	return set_smc_args(RMMD_RMI_REQ_COMPLETE, ret, 0, 0, 0, 0, 0, 0);
+	return set_smc_args(RMM_RMI_REQ_COMPLETE, ret, 0, 0, 0, 0, 0, 0);
 }
 
 /*******************************************************************************