PREFIX ?= arm-none-eabi
CC      = $(PREFIX)-gcc
LD      = $(PREFIX)-gcc
OBJCOPY = $(PREFIX)-objcopy
OBJDUMP = $(PREFIX)-objdump
FLASH   = $(shell which st-flash)

TOOLCHAIN_DIR ?= ../../../STM/libopencm3

CFLAGS   += -Os -g \
            -Wall -Wextra -Wimplicit-function-declaration -Wredundant-decls -Wstrict-prototypes -Wundef -Wshadow \
            -fno-common -mcpu=cortex-m3 -mthumb -msoft-float -MD -DSTM32F2 \
            -I$(TOOLCHAIN_DIR)/include
LDSCRIPT ?= $(NAME).ld
LDFLAGS  += --static -Wl,--start-group -lc -lgcc -lnosys -Wl,--end-group \
            -L$(TOOLCHAIN_DIR)/lib -L$(TOOLCHAIN_DIR)/lib/stm32/f2 \
            -T$(LDSCRIPT) -nostartfiles -Wl,--gc-sections \
            -mthumb -march=armv7 -mfix-cortex-m3-ldrd -msoft-float
OBJS     += $(NAME).o

all: images

images: $(NAME).bin

flash: $(NAME).bin
	$(FLASH) write $(NAME).bin 0x8000000

$(NAME).bin: $(NAME).elf
	$(OBJCOPY) -Obinary $(NAME).elf $(NAME).bin

$(NAME).hex: $(NAME).elf
	$(OBJCOPY) -Oihex $(NAME).elf $(NAME).hex

$(NAME).srec: $(NAME).elf
	$(OBJCOPY) -Osrec $(NAME).elf $(NAME).srec

$(NAME).list: $(NAME).elf
	$(OBJDUMP) -S $(NAME).elf > $(NAME).list

$(NAME).elf: $(OBJS) $(LDSCRIPT) $(TOOLCHAIN_DIR)/lib/libopencm3_stm32f2.a
	$(LD) -o $(NAME).elf $(OBJS) -lopencm3_stm32f2 $(LDFLAGS)

%.o: %.c Makefile
	$(CC) $(CFLAGS) -o $@ -c $<

clean:
	rm -f *.o
	rm -f *.d
	rm -f *.elf
	rm -f *.bin
	rm -f *.hex
	rm -f *.srec
	rm -f *.list
	rm -f usb.pb*