diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index e4ddafd6d12d..e077c55c21ab 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -252,7 +252,10 @@ DTC ?= $(objtree)/scripts/dtc/dtc
 
 # Disable noisy checks by default
 ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),)
-DTC_FLAGS += -Wno-unit_address_vs_reg \
+DTC_FLAGS += -Wno-unit_address_vs_reg
+endif
+ifeq ($(DTC_EXT),)
+DTC_FLAGS += -Wno-simple_bus_reg \
 	-Wno-unit_address_format \
 	-Wno-avoid_unnecessary_addr_size \
 	-Wno-alias_paths \