#Android makefile to build kernel as a part of Android Build
PERL		= perl

TARGET_KERNEL_ARCH := $(strip $(TARGET_KERNEL_ARCH))
ifeq ($(TARGET_KERNEL_ARCH),)
KERNEL_ARCH := arm
else
KERNEL_ARCH := $(TARGET_KERNEL_ARCH)
endif

TARGET_KERNEL_HEADER_ARCH := $(strip $(TARGET_KERNEL_HEADER_ARCH))
ifeq ($(TARGET_KERNEL_HEADER_ARCH),)
KERNEL_HEADER_ARCH := $(KERNEL_ARCH)
else
$(warning Forcing kernel header generation only for '$(TARGET_KERNEL_HEADER_ARCH)')
KERNEL_HEADER_ARCH := $(TARGET_KERNEL_HEADER_ARCH)
endif

TARGET_KERNEL_CROSS_COMPILE_PREFIX := $(strip $(TARGET_KERNEL_CROSS_COMPILE_PREFIX))
ifeq ($(TARGET_KERNEL_CROSS_COMPILE_PREFIX),)
KERNEL_CROSS_COMPILE := arm-eabi-
else
KERNEL_CROSS_COMPILE := $(TARGET_KERNEL_CROSS_COMPILE_PREFIX)
endif

ifeq ($(TARGET_PREBUILT_KERNEL),)

KERNEL_OUT := $(TARGET_OUT_INTERMEDIATES)/KERNEL_OBJ
KERNEL_CONFIG := $(KERNEL_OUT)/.config

ifeq ($(TARGET_USES_UNCOMPRESSED_KERNEL),true)
$(info Using uncompressed kernel)
TARGET_PREBUILT_INT_KERNEL := $(KERNEL_OUT)/arch/$(KERNEL_ARCH)/boot/Image
else
TARGET_PREBUILT_INT_KERNEL := $(KERNEL_OUT)/arch/$(KERNEL_ARCH)/boot/zImage
endif

ifeq ($(TARGET_KERNEL_APPEND_DTB), true)
$(info Using appended DTB)
TARGET_PREBUILT_INT_KERNEL := $(TARGET_PREBUILT_INT_KERNEL)-dtb
endif

KERNEL_HEADERS_INSTALL := $(KERNEL_OUT)/usr
KERNEL_MODULES_INSTALL := system
KERNEL_MODULES_OUT := $(TARGET_OUT)/lib/modules
# relative path from KERNEL_OUT to kernel source directory
KERNEL_SOURCE_RELATIVE_PATH := ../../../../../../kernel


TARGET_PREBUILT_KERNEL := $(TARGET_PREBUILT_INT_KERNEL)

define mv-modules
mdpath=`find $(KERNEL_MODULES_OUT) -type f -name modules.order`;\
if [ "$$mdpath" != "" ];then\
mpath=`dirname $$mdpath`;\
ko=`find $$mpath/kernel -type f -name *.ko`;\
for i in $$ko; do mv $$i $(KERNEL_MODULES_OUT)/; done;\
fi
endef

define clean-module-folder
mdpath=`find $(KERNEL_MODULES_OUT) -type f -name modules.order`;\
if [ "$$mdpath" != "" ];then\
mpath=`dirname $$mdpath`; rm -rf $$mpath;\
fi
endef

include kernel/defconfig.mk

KERNEL_HEADER_DEFCONFIG := $(strip $(KERNEL_HEADER_DEFCONFIG))
ifeq ($(KERNEL_HEADER_DEFCONFIG),)
KERNEL_HEADER_DEFCONFIG := $(TARGET_DEFCONFIG)
endif

define do-kernel-config
	( cp $(3) $(2) && $(7) -C $(4) O=$(1) ARCH=$(5) CROSS_COMPILE=$(6) KBUILD_BUILD_USER=$(TARGET_KERNEL_BUILD_USER) KBUILD_BUILD_HOST=$(TARGET_KERNEL_BUILD_HOST) defoldconfig ) || ( rm -f $(2) && false )
endef

$(KERNEL_OUT):
	mkdir -p $(KERNEL_OUT)

$(KERNEL_CONFIG): $(KERNEL_OUT) $(TARGET_DEFCONFIG)
	$(call do-kernel-config,../$(KERNEL_OUT),$@,$(TARGET_DEFCONFIG),kernel,$(KERNEL_ARCH),$(KERNEL_CROSS_COMPILE),$(MAKE))

$(TARGET_PREBUILT_INT_KERNEL): $(KERNEL_OUT) $(KERNEL_CONFIG) $(KERNEL_HEADERS_INSTALL)
	$(hide) rm -rf $(KERNEL_OUT)/arch/$(KERNEL_ARCH)/boot/dts
	$(MAKE) -C kernel KBUILD_RELSRC=$(KERNEL_SOURCE_RELATIVE_PATH) O=../$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) CROSS_COMPILE=$(KERNEL_CROSS_COMPILE) KBUILD_BUILD_USER=$(TARGET_KERNEL_BUILD_USER) KBUILD_BUILD_HOST=$(TARGET_KERNEL_BUILD_HOST)
	$(MAKE) -C kernel KBUILD_RELSRC=$(KERNEL_SOURCE_RELATIVE_PATH) O=../$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) CROSS_COMPILE=$(KERNEL_CROSS_COMPILE) KBUILD_BUILD_USER=$(TARGET_KERNEL_BUILD_USER) KBUILD_BUILD_HOST=$(TARGET_KERNEL_BUILD_HOST) dtbs
	$(MAKE) -C kernel KBUILD_RELSRC=$(KERNEL_SOURCE_RELATIVE_PATH) O=../$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) CROSS_COMPILE=$(KERNEL_CROSS_COMPILE) KBUILD_BUILD_USER=$(TARGET_KERNEL_BUILD_USER) KBUILD_BUILD_HOST=$(TARGET_KERNEL_BUILD_HOST) modules
	$(MAKE) -C kernel KBUILD_RELSRC=$(KERNEL_SOURCE_RELATIVE_PATH) O=../$(KERNEL_OUT) INSTALL_MOD_PATH=../../$(KERNEL_MODULES_INSTALL) INSTALL_MOD_STRIP="--strip-debug --remove-section=.note.gnu.build-id" ARCH=$(KERNEL_ARCH) CROSS_COMPILE=$(KERNEL_CROSS_COMPILE) KBUILD_BUILD_USER=$(TARGET_KERNEL_BUILD_USER) KBUILD_BUILD_HOST=$(TARGET_KERNEL_BUILD_HOST) modules_install
	$(mv-modules)
	$(clean-module-folder)

$(KERNEL_HEADERS_INSTALL): $(KERNEL_OUT) $(KERNEL_CONFIG)
	$(hide) rm -f ../$(KERNEL_CONFIG)
	$(call do-kernel-config,../$(KERNEL_OUT),$(KERNEL_CONFIG),$(KERNEL_HEADER_DEFCONFIG),kernel,$(KERNEL_HEADER_ARCH),$(KERNEL_CROSS_COMPILE),$(MAKE))
	$(MAKE) -C kernel O=../$(KERNEL_OUT) ARCH=$(KERNEL_HEADER_ARCH) CROSS_COMPILE=$(KERNEL_CROSS_COMPILE) KBUILD_BUILD_USER=$(TARGET_KERNEL_BUILD_USER) KBUILD_BUILD_HOST=$(TARGET_KERNEL_BUILD_HOST) headers_install
	$(hide) rm -f ../$(KERNEL_CONFIG)
	$(call do-kernel-config,../$(KERNEL_OUT),$(KERNEL_CONFIG),$(TARGET_DEFCONFIG),kernel,$(KERNEL_ARCH),$(KERNEL_CROSS_COMPILE),$(MAKE))

kerneltags: $(KERNEL_OUT) $(KERNEL_CONFIG)
	$(MAKE) -C kernel O=../$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) CROSS_COMPILE=$(KERNEL_CROSS_COMPILE) KBUILD_BUILD_USER=$(TARGET_KERNEL_BUILD_USER) KBUILD_BUILD_HOST=$(TARGET_KERNEL_BUILD_HOST) tags

kernelconfig: $(KERNEL_OUT) $(KERNEL_CONFIG)
	env KCONFIG_NOTIMESTAMP=true \
	     $(MAKE) -C kernel O=../$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) CROSS_COMPILE=$(KERNEL_CROSS_COMPILE) KBUILD_BUILD_USER=$(TARGET_KERNEL_BUILD_USER) KBUILD_BUILD_HOST=$(TARGET_KERNEL_BUILD_HOST) menuconfig
	env KCONFIG_NOTIMESTAMP=true \
	     $(MAKE) -C kernel O=../$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) CROSS_COMPILE=$(KERNEL_CROSS_COMPILE) KBUILD_BUILD_USER=$(TARGET_KERNEL_BUILD_USER) KBUILD_BUILD_HOST=$(TARGET_KERNEL_BUILD_HOST) savedefconfig
	cp $(KERNEL_OUT)/defconfig kernel/arch/$(KERNEL_ARCH)/configs/$(KERNEL_DEFCONFIG)

endif