diff --git a/docs/getting_started/image-terminology.rst b/docs/getting_started/image-terminology.rst
index 5993d6e..a90ec0b 100644
--- a/docs/getting_started/image-terminology.rst
+++ b/docs/getting_started/image-terminology.rst
@@ -92,6 +92,14 @@
 abbreviated name should identify the vendor as well as the image
 function. For example, ``AP_BL3_ARM_RAS``.
 
+Realm Monitor Management Firmware: ``RMM``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This is the Realm-EL2 firmware. It is required if
+:ref:`Realm Management Extension (RME)` feature is enabled. If a path to RMM
+image is not provided, TF-A builds Test Realm Payload (TRP) image by default
+and uses it as the RMM image.
+
 SCP Boot ROM: ``SCP_BL1`` (previously ``BL0``)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
diff --git a/docs/getting_started/rt-svc-writers-guide.rst b/docs/getting_started/rt-svc-writers-guide.rst
index b3758b8..5a4be4d 100644
--- a/docs/getting_started/rt-svc-writers-guide.rst
+++ b/docs/getting_started/rt-svc-writers-guide.rst
@@ -200,13 +200,13 @@
        SMC_RET1(handle, SMC_UNK);
 
 #. Determining if the requested function is valid for the calling security
-   state. SMC Calls can be made from both the normal and trusted worlds and
+   state. SMC Calls can be made from Non-secure, Secure or Realm worlds and
    the framework will forward all calls to the service handler.
 
    The ``flags`` parameter to this function indicates the caller security state
-   in bit[0], where a value of ``1`` indicates a non-secure caller. The
-   ``is_caller_secure(flags)`` and ``is_caller_non_secure(flags)`` can be used to
-   test this condition.
+   in bits 0 and 5. The ``is_caller_secure(flags)``, ``is_caller_non_secure(flags)``
+   and ``is_caller_realm(flags)`` helper functions can be used to determine whether
+   the caller's security state is Secure, Non-secure or Realm respectively.
 
    If invalid, the request should be completed with:
 
@@ -314,7 +314,7 @@
 
 --------------
 
-*Copyright (c) 2014-2020, Arm Limited and Contributors. All rights reserved.*
+*Copyright (c) 2014-2021, Arm Limited and Contributors. All rights reserved.*
 
 .. _SMCCC: https://developer.arm.com/docs/den0028/latest
 .. _PSCI: http://infocenter.arm.com/help/topic/com.arm.doc.den0022c/DEN0022C_Power_State_Coordination_Interface.pdf