--- zzzz-none-000/linux-4.9.276/arch/arc/boot/dts/Makefile	2021-07-20 14:21:16.000000000 +0000
+++ falcon-5530-750/linux-4.9.276/arch/arc/boot/dts/Makefile	2023-04-05 08:19:00.000000000 +0000
@@ -10,8 +10,6 @@
 
 .SECONDARY: $(obj)/$(builtindtb-y).dtb.S
 
-dtstree		:= $(srctree)/$(src)
-dtb-$(CONFIG_OF_ALL_DTBS) := $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
-
-always := $(dtb-y)
-clean-files := *.dtb  *.dtb.S
+# for CONFIG_OF_ALL_DTBS test
+dtstree	:= $(srctree)/$(src)
+dtb-	:= $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))