Makefile to compile a single device-tree

Makefile

# Makefile to compile a single device-tree

# Main .dts file without extension
MAIN_DTS_FILE:=sun6i-a31s-sinovoip-bpi-m2

# C preprocessor flags (for dts parsing)
DTS_CPP_FLAGS := -nostdinc -Iinclude -undef -D__DTS__ -x assembler-with-cpp


## Targets
all: ${MAIN_DTS_FILE}.dtb

# Temporal file generated by the C preprocessor
${MAIN_DTS_FILE}.dts.tmp:
	cpp -Wp,-MD,${MAIN_DTS_FILE}.dts.dep.tmp ${DTS_CPP_FLAGS} -o ${MAIN_DTS_FILE}.dts.tmp ${MAIN_DTS_FILE}.dts

# Actual compilation using the temporal file as input
${MAIN_DTS_FILE}.dtb: ${MAIN_DTS_FILE}.dts.tmp
	dtc -O dtb -o ${MAIN_DTS_FILE}.dtb -b 0 -d ${MAIN_DTS_FILE}.dts.dep.tmp ${MAIN_DTS_FILE}.dts.tmp

# Clean only temporal files
clean_tmp:
	rm -rf *.tmp

# Clean all temporal and outputs files
clean: clean_tmp
	rm -rf *.dtb

Great!