-dtb-$(CONFIG_ARCH_THUNDER) += thunder-88xx.dtb
-dtb-$(CONFIG_ARCH_VEXPRESS) += rtsm_ve-aemv8a.dtb foundation-v8.dtb
-dtb-$(CONFIG_ARCH_XGENE) += apm-mustang.dtb
+dts-dirs += apm
+dts-dirs += arm
+dts-dirs += cavium
always := $(dtb-y)
+subdir-y := $(dts-dirs)
clean-files := *.dtb