diff --git a/make_helpers/defaults.mk b/make_helpers/defaults.mk
index 5217a85..e94f3c3 100644
--- a/make_helpers/defaults.mk
+++ b/make_helpers/defaults.mk
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2016-2020, ARM Limited. All rights reserved.
+# Copyright (c) 2016-2021, ARM Limited. All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
 #
@@ -209,6 +209,9 @@
 # Software Delegated Exception support
 SDEI_SUPPORT            	:= 0
 
+# True Random Number firmware Interface
+TRNG_SUPPORT            	:= 0
+
 # Whether code and read-only data should be put on separate memory pages. The
 # platform Makefile is free to override this value.
 SEPARATE_CODE_AND_RODATA	:= 0