SEL4_DIR  := $(call select_from_ports,sel4)/src/kernel/sel4
TOOLS_DIR := $(call select_from_ports,sel4_tools)/src/tool/sel4_tools

#
# Execute the kernel build only at the second build stage when we know
# about the complete build settings (e.g., the 'CROSS_DEV_PREFIX') and the
# current working directory is the library location.
#
ifeq ($(called_from_lib_mk),yes)
all: build_kernel
else
all:
endif

ifeq ($(CCACHE),yes)
SEL4_CCACHE=ccache
else
SEL4_CCACHE=
endif

configured_kernel:
	$(VERBOSE) cmake -DCROSS_COMPILER_PREFIX=$(CROSS_DEV_PREFIX) \
	                 -DCMAKE_TOOLCHAIN_FILE=$(SEL4_DIR)/gcc.cmake \
	                 -DKernelARMPlatform=sabre \
	                 -G Ninja \
	                 -C $(SEL4_DIR)/configs/ARM_verified.cmake \
	                 $(SEL4_DIR) \
	&& echo -e "\n#define CONFIG_PRINTING 1"                        >>gen_config/kernel/gen_config.h \
	&& echo -e "#define CONFIG_DEBUG_BUILD 1"                        >>gen_config/kernel/gen_config.h \
	&& echo -e "#define CONFIG_ENABLE_BENCHMARKS 1"                  >>gen_config/kernel/gen_config.h \
	&& echo -e "#define CONFIG_BENCHMARK_TRACK_UTILISATION 1"        >>gen_config/kernel/gen_config.h \
	&& echo -e "#define CONFIG_SET_TLS_BASE_SELF 1"                  >>gen_config/kernel/gen_config.h \
	&& echo -e "#define CONFIG_HAVE_FPU 1"                           >>gen_config/kernel/gen_config.h \
	&& echo -e "#define CONFIG_AARCH32_FPU_ENABLE_CONTEXT_SWITCH  1" >>gen_config/kernel/gen_config.h \
	&& echo -e "#define CONFIG_FPU_MAX_RESTORES_SINCE_SWITCH  64"    >>gen_config/kernel/gen_config.h \
	\
	&& sed -e "s/CONFIG_NUM_DOMAINS 16/CONFIG_NUM_DOMAINS 1/"                    \
	       -e "s/CONFIG_ROOT_CNODE_SIZE_BITS 12/CONFIG_ROOT_CNODE_SIZE_BITS 15/" \
	          gen_config/kernel/gen_config.h   >gen_config/kernel/gen_config.tmp \
	&& mv     gen_config/kernel/gen_config.tmp  gen_config/kernel/gen_config.h   \
	&& touch configured_kernel

elfloader/elfloader.o: configured_kernel
	$(VERBOSE)cp -r $(TOOLS_DIR)/elfloader-tool $(LIB_CACHE_DIR)/$(LIB)/elfloader
	$(VERBOSE)mkdir -p $(LIB_CACHE_DIR)/$(LIB)/elfloader/tools/kbuild
	$(VERBOSE)mkdir -p $(LIB_CACHE_DIR)/$(LIB)/elfloader/include/generated
	$(VERBOSE)ln -s $(TOOLS_DIR)/common-tool/common.mk $(LIB_CACHE_DIR)/$(LIB)/elfloader/
	$(VERBOSE)ln -s $(TOOLS_DIR)/common-tool/files_to_obj.sh $(LIB_CACHE_DIR)/$(LIB)/elfloader/
	$(VERBOSE)ln -s $(TOOLS_DIR)/kbuild-tool/Kbuild.include $(LIB_CACHE_DIR)/$(LIB)/elfloader/tools/kbuild/
	$(VERBOSE)ln -s $(LIB_CACHE_DIR)/$(LIB)/gen_config/kernel/gen_config.h $(LIB_CACHE_DIR)/$(LIB)/elfloader/include/generated/autoconf.h
	$(VERBOSE)$(MAKE) -C $(LIB_CACHE_DIR)/$(LIB)/elfloader \
	          TOOLPREFIX=$(CROSS_DEV_PREFIX) \
	          ARCH=arm PLAT=$(PLAT) ARMV=armv7-a __ARM_32__="y" \
	          CPU=$(CPU) ASFLAGS="-march=armv7-a" \
	          CFLAGS="-march=armv7-a -D__KERNEL_32__ -fno-builtin" \
	          SEL4_COMMON=. CCACHE=$(SEL4_CCACHE) SOURCE_DIR=. STAGE_DIR=. \
	          srctree=.

build_kernel: elfloader/elfloader.o
	$(VERBOSE) ninja kernel.elf && \
	$(CUSTOM_STRIP) -o kernel.elf.strip kernel.elf