all: $(TARGET)

MK_FILE_PATH = $(lastword $(MAKEFILE_LIST))
PRJ_DIR      = $(abspath $(dir $(MK_FILE_PATH)))

# Hardcoded paths
OPENOCD_BIN	:= /usr/bin/riscv-openocd
RISCV_SDK_DIR	:= $(abspath $(PRJ_DIR)/../../riscv-sdk)
OUT_DIR	:= bin

# Variables
SDK_INC		:= $(RISCV_SDK_DIR)/include
SDK_WRAP	:= $(RISCV_SDK_DIR)/libwrap
SDK_OPENOCD_CFG	:= $(RISCV_SDK_DIR)/openocd.cfg

# libwrap config
include $(SDK_WRAP)/libwrap.mk

# SDK sources
SDK_SRC_ASM	:= \
		$(RISCV_SDK_DIR)/entry.S \
		$(RISCV_SDK_DIR)/start.S

SDK_SRC_C	:= \
		$(RISCV_SDK_DIR)/init.c
SDK_LINK_SCRIPT	:= \
		$(RISCV_SDK_DIR)/flash.lds

# Variable used by libwrap.mk
INCLUDES	:= -I$(RISCV_SDK_DIR)/include

# Platform specific: HiFive1

#Name of variable required by libwrap.mk
ARCH_FLAGS	+= \
		-march=rv32imac -mabi=ilp32 -mcmodel=medany

CFLAGS		+= \
		-O3 -fno-builtin-printf \
		-Wall -Wextra -Wshadow -fno-common \
		-include sys/cdefs.h \
		$(ARCH_FLAGS) \
		$(LOCAL_CFLAGS)

LDFLAGS		+= \
		-static \
		-L$(RISCV_SDK_DIR) \
		-T$(SDK_LINK_SCRIPT) \
		-nostartfiles \
		--specs=nano.specs \
		-Wl,--gc-sections \
		$(LOCAL_LDFLAGS)

# Common targets
OBJ_S 		:= \
		$(LOCAL_SRC_S:.S=.o) \
		$(SDK_SRC_ASM:.S=.o)
OBJ_C		:= \
		$(LOCAL_SRC_C:.c=.o) \
		$(SDK_SRC_C:.c=.o)

# Compilation targets
$(OBJ_S): %.o: %.S
	mkdir -p $(OUT_DIR)/$(dir $@)
	$(CC) $(ARCH_FLAGS) -I$(SDK_INC) $(OPT) -c -o $(OUT_DIR)/$@ $<

$(OBJ_C): %.o: %.c
	mkdir -p $(OUT_DIR)/$(dir $@)
	$(CC) -I$(SDK_INC) $(CFLAGS) $(OPT) -c -o $(OUT_DIR)/$@ $<

$(TARGET): $(OBJ_C) $(OBJ_S) $(LIBWRAP)
	$(CC) -I$(SDK_INC) $(CFLAGS) $(OPT) \
	$(addprefix $(OUT_DIR)/,$(OBJ_S)) \
	$(addprefix $(OUT_DIR)/,$(OBJ_C)) \
	-o $(OUT_DIR)/$@ $(LDFLAGS)
clean:
	rm -rf $(OUT_DIR)
	rm -rf $(LIBWRAP)

run:
	$(OPENOCD_BIN) -s "sdk" -f $(SDK_OPENOCD_CFG) & \
	$(GDB) \
		"$(OUT_DIR)/$(TARGET)" \
		--batch \
		-ex "set remotetimeout 240" \
		-ex "target extended-remote localhost:3333" \
		-ex "monitor reset halt" \
		-ex "monitor flash protect 0 64 last off" \
		-ex "load" \
		-ex "monitor resume" \
		-ex "monitor shutdown" \
		-ex "quit"

.PHONY: clean all run