diff --git a/sys/tools/fdt/make_dtb.sh b/sys/tools/fdt/make_dtb.sh
--- a/sys/tools/fdt/make_dtb.sh
+++ b/sys/tools/fdt/make_dtb.sh
@@ -21,6 +21,7 @@
 
 for d in ${dts}; do
     dtb="${dtb_path}/$(basename "$d" .dts).dtb"
+    dts_path=`dirname $d`
     ${CPP} -P -x assembler-with-cpp -I "$S/dts/include" -I "$S/contrib/device-tree/include" -I "$S/dts/${MACHINE}" -I "$S/contrib/device-tree/src/${MACHINE}" -I "$S/contrib/device-tree/src/" -include "$d" -include "$S/dts/freebsd-compatible.dts" /dev/null |
-	${DTC} -@ -O dtb -o "$dtb" -b 0 -p 1024 -i "$S/dts/${MACHINE}" -i "$S/contrib/device-tree/src/${MACHINE}" -i "$S/contrib/device-tree/src/"
+	${DTC} -@ -O dtb -o "$dtb" -b 0 -p 1024 -i "$S/dts/${MACHINE}" -i "$S/contrib/device-tree/src/${MACHINE}" -i "$S/contrib/device-tree/src/" -i "$dts_path"
 done