TARGET = firmware

DEBUG = 1
OPT = -O0

BUILD_DIR = build

C_SOURCES =  \
Core/Src/main.c \
Core/Src/stm32g0xx_it.c \
Core/Src/stm32g0xx_hal_msp.c \
Core/Src/system_stm32g0xx.c \
Core/Src/syscalls.c \
Core/Src/sysmem.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_rcc.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_cortex.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_rcc_ex.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_pwr.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_pwr_ex.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_iwdg.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_uart_ex.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_uart.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_gpio.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_i2c.c \
Drivers/STM32G0xx_HAL_Driver/Src/stm32g0xx_hal_i2c_ex.c

ASM_SOURCES = \
Core/Startup/startup_stm32g031y8yx.s

PREFIX = arm-none-eabi-
CC = $(PREFIX)gcc
AS = $(PREFIX)gcc -x assembler-with-cpp
CP = $(PREFIX)objcopy
SZ = $(PREFIX)size

CPU = -mcpu=cortex-m0plus
MCU = $(CPU) -mthumb $(FPU) $(FLOAT-ABI)

C_DEFS = \
-DUSE_HAL_DRIVER \
-DSTM32G071xx

C_INCLUDES = \
-ICore/Inc \
-IDrivers/STM32G0xx_HAL_Driver/Inc \
-IDrivers/STM32G0xx_HAL_Driver/Inc/Legacy \
-IDrivers/CMSIS/Device/ST/STM32G0xx/Include \
-IDrivers/CMSIS/Include


ASFLAGS = $(MCU) $(AS_DEFS) $(AS_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections
CFLAGS = $(MCU) $(C_DEFS) $(C_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections

ifeq ($(DEBUG), 1)
CFLAGS += -ggdb3
endif

CFLAGS += -MMD -MP -MF"$(@:%.o=%.d)"

LDSCRIPT = STM32G031Y8YX_Flash.ld

LIBS = -lc -lm -lnosys
LIBDIR =
LDFLAGS = $(MCU) -specs=nano.specs -T$(LDSCRIPT) $(LIBDIR) $(LIBS) -Wl,-Map=$(BUILD_DIR)/$(TARGET).map,--cref -Wl,--gc-sections

all: $(BUILD_DIR)/$(TARGET).elf $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).bin

OBJECTS = $(addprefix $(BUILD_DIR)/,$(notdir $(C_SOURCES:.c=.o)))
vpath %.c $(sort $(dir $(C_SOURCES)))

OBJECTS += $(addprefix $(BUILD_DIR)/,$(notdir $(ASM_SOURCES:.s=.o)))
vpath %.s $(sort $(dir $(ASM_SOURCES)))

$(BUILD_DIR)/%.o: %.c Makefile | $(BUILD_DIR) 
	$(CC) -c $(CFLAGS) -Wa,-a,-ad,-alms=$(BUILD_DIR)/$(notdir $(<:.c=.lst)) $< -o $@

$(BUILD_DIR)/%.o: %.s Makefile | $(BUILD_DIR)
	$(AS) -c $(CFLAGS) $< -o $@

$(BUILD_DIR)/$(TARGET).elf: $(OBJECTS) Makefile
	$(CC) $(OBJECTS) $(LDFLAGS) -o $@
	$(SZ) $@

$(BUILD_DIR):
	mkdir $@

clean:
	-rm -rf $(BUILD_DIR)

-include $(wildcard $(BUILD_DIR)/*.d)