# Aedrix root Makefile
# Copyright (C) 2012, Aaron Lindsay <aaron@aclindsay.com>

# Config options for the code itself (should be separated from the Makefile sometime)
ARCH = arm

# Config options concerning the build process itself
VERBOSE ?= 0 # 1 shows all compiler flags, 0 shows cleaner output
V = $(if $(VERBOSE:1=),@) # Use this to prefix commands that should only be shown when VERBOSE==1

# Define the tools to be used
TOOL_PREFIX = arm-elf-
AS = $(TOOL_PREFIX)as
CC = $(TOOL_PREFIX)gcc
LD = $(TOOL_PREFIX)ld
OBJCOPY = $(TOOL_PREFIX)objcopy
OBJDUMP = $(TOOL_PREFIX)objdump

# Define the flags we'll need for our tools
INCLUDES = -I include
KCFLAGS = -g -Wall -Wextra -Werror -nostdlib -nostartfiles -fno-builtin -std=gnu99 $(INCLUDES)
KLDFLAGS = -T link.ld -L /usr/lib/gcc/arm-elf/4.7.0/
EXTRA_LIBS = -lgcc

# Define KOBJS as a 'simply expanded' variable
KOBJS :=

# Initialize sub-directory Makefile inclusion
BASEDIR = $(shell pwd)
SUBDIRS := boot kernel devices
ifneq (,$(SUBDIRS))
	include $(patsubst %,%/kernel.mk,$(SUBDIRS))
endif

.PHONY: all clean boot boot-gdb

all: aedrix-kernel.img aedrix-kernel.elf

aedrix-kernel.elf: $(KOBJS)
	@echo '     LD   $@'
	$(V)$(LD) $(KLDFLAGS) -o $@ $(KOBJS) $(EXTRA_LIBS)

aedrix-kernel.objdump: aedrix-kernel.elf
	@echo 'OBJDUMP   $@'
	$(V)$(OBJDUMP) -D $< > $@

aedrix-kernel.img: aedrix-kernel.elf
	@echo 'OBJCOPY   $@'
	$(V)$(OBJCOPY) $< -O binary $@

%.o: %.c
	@echo '     CC   $@'
	$(V)$(CC) $(KCFLAGS) -MD -c -o $@ $<
	@# Automatic dependency generation fixups (http://mad-scientist.net/make/autodep.html)
	@cp $*.d $(*D)/.$(*F).d; \
		sed -e 's/#.*//' -e 's/^[^:]*: *//' -e 's/ *\\$$//' \
		-e '/^$$/ d' -e 's/$$/ :/' < $*.d >> $(*D)/.$(*F).d; \
		rm -f $*.d

%.o: %.S
	@echo '     AS   $@'
	$(V)$(CC) $(KCFLAGS) -MD -c -o $@ $<
	@# Automatic dependency generation fixups (http://mad-scientist.net/make/autodep.html)
	@cp $*.d $(*D)/.$(*F).d; \
		sed -e 's/#.*//' -e 's/^[^:]*: *//' -e 's/ *\\$$//' \
		-e '/^$$/ d' -e 's/$$/ :/' < $*.d >> $(*D)/.$(*F).d; \
		rm -f $*.d

clean:
	@echo '  CLEAN   *.o'
	$(V)rm -f $(KOBJS)
	@echo '  CLEAN   .*.d'
	$(V)rm -f $(DEPENDENCY_FILES)
	@echo '  CLEAN   aedrix-kernel.elf'
	$(V)rm -f aedrix-kernel.elf
	@echo '  CLEAN   aedrix-kernel.objdump'
	$(V)rm -f aedrix-kernel.objdump
	@echo '  CLEAN   aedrix-kernel.img'
	$(V)rm -f aedrix-kernel.img

boot: aedrix-kernel.img
	$(V)qemu-system-arm -m 1024 -M vexpress-a9 -kernel aedrix-kernel.img -serial stdio
boot-gdb: aedrix-kernel.img
	$(V)qemu-system-arm -m 1024 -M vexpress-a9 -kernel aedrix-kernel.img -serial stdio -S -s

DEPENDENCY_FILES = $(foreach file,$(KOBJS), $(dir $(file)).$(notdir $(basename $(file))).d)
-include $(DEPENDENCY_FILES)