diff --git a/make_helpers/arch_features.mk b/make_helpers/arch_features.mk
index 9533e98..42f969b 100644
--- a/make_helpers/arch_features.mk
+++ b/make_helpers/arch_features.mk
@@ -413,6 +413,12 @@
 ENABLE_BRBE_FOR_NS			?=	0
 
 #----
+# 9.3
+#----
+# Flag to enable access to Arm v9.3 FEAT_D128 extension
+ENABLE_FEAT_D128			?=	0
+
+#----
 #9.4
 #----