build-kernel

#!/bin/sh
# ------------------------------------------------------------------------------
# build-kernel - Builds the ev3dev kernel.
# ------------------------------------------------------------------------------

echo
echo -------------------------------------------------------------------------------
echo BUILDING KERNEL
echo -------------------------------------------------------------------------------
echo

set -e

. ./setup-env

kernel_src_path="$EV3DEV_KERNEL"
obj_path="$EV3DEV_OBJ"
kernel_install_path="$EV3DEV_INSTALL_KERNEL"
modules_install_path="$EV3DEV_INSTALL_MODULES"
dtbs_install_path="$EV3DEV_INSTALL_DTBS"
make_args="$EV3DEV_MAKE_ARGS -C ${kernel_src_path}
	KBUILD_OUTPUT=${obj_path}
	ARCH=arm
	CROSS_COMPILE=$EV3DEV_TOOLCHAIN/$EV3DEV_ABI"
extra_default_targets="$EV3DEV_EXTRA_DEFAULT_TARGETS"
uenv_txt_install_path="$EV3DEV_INSTALL_UENV_TXT"

if [ ! -d "${obj_path}" ]
then
	echo "CREATING OBJ DIRECTORY"
	make ${make_args} mrproper
fi

if [ ! -f "${obj_path}/.config" ]
then
	echo "LOADING DEFAULT KERNEL CONFIGURATION"
	make ${make_args} defconfig KBUILD_DEFCONFIG=${EV3DEV_DEFCONFIG}
fi

if [ $# -eq 0 ]
then
	echo "CROSS COMPILING KERNEL"
	make ${make_args} ${extra_default_targets} modules

	if [ ! -d "${kernel_install_path}" ]
	then
		echo "CREATING KERNEL INSTALL DIRECTORY"
		mkdir -p "${kernel_install_path}"
	fi

	if [ ! -d "${modules_install_path}" ]
	then
		echo "CREATING MODULE INSTALL DIRECTORY"
		mkdir -p "${modules_install_path}"
	fi

	echo "COPYING BOOTABLE IMAGE TO INSTALL DIRECTORY"
	if [ "$EV3DEV_KERNEL_FLAVOR" = "ev3" ]; then
		if [ -n "$EV3DEV_APPEND_DTB" ]; then
			cat ${obj_path}/arch/arm/boot/zImage ${obj_path}/arch/arm/boot/dts/$EV3DEV_APPEND_DTB > ${obj_path}/arch/arm/boot/zImage+dtb
			mkimage -A arm -O linux -T kernel -C none -a 0xC0008000 -e 0xC0008000 \
				-n kernel -d ${obj_path}/arch/arm/boot/zImage+dtb ${obj_path}/arch/arm/boot/uImage
		fi
		cp ${obj_path}/arch/arm/boot/uImage ${kernel_install_path}
	elif [ "$EV3DEV_KERNEL_FLAVOR" = "bb.org" ]; then
		cp ${obj_path}/arch/arm/boot/zImage ${kernel_install_path}
	elif [ "$EV3DEV_KERNEL_FLAVOR" = "rpi" ]; then
		cp ${obj_path}/arch/arm/boot/zImage ${kernel_install_path}/kernel.img
	elif [ "$EV3DEV_KERNEL_FLAVOR" = "rpi2" ]; then
		cp ${obj_path}/arch/arm/boot/zImage ${kernel_install_path}/kernel7.img
	fi

	echo "COPYING MODULES TO INSTALL DIRECTORY"
	make ${make_args} modules_install INSTALL_MOD_PATH=${modules_install_path}

	if [ ! -z ${EV3DEV_INSTALL_DTBS} ]; then
		echo "COPYING DEVICE TREE BLOCKS TO INSTALL DIRECTORY"
		make ${make_args} dtbs_install INSTALL_DTBS_PATH=${dtbs_install_path}
	fi

	if [ ! -z ${EV3DEV_COPY_DTB} ]; then
		echo "COPYING DEVICE TREE TO KERNEL INSTALL DIRECTORY"
		cp ${dtbs_install_path}/${EV3DEV_COPY_DTB} ${kernel_install_path}/${EV3DEV_COPY_DTB}
	fi

	if [ "$EV3DEV_KERNEL_FLAVOR" = "bb.org" ]; then
		echo "COPYING UENV.TXT TO INSTALL DIRECTORY"
		cat > ${uenv_txt_install_path}/uEnv.txt.new <<EOF
cape=$EV3DEV_CAPE

cmdline=splash console=tty1

loadaddr=0x82000000
fdtaddr=0x88000000
rdaddr=0x88080000

initrd_high=0xffffffff
fdt_high=0xffffffff

##These are needed to be compliant with Debian 2014-05-14 u-boot.

loadximage=echo debug: [/zImage] ... ; load mmc 0:1 \${loadaddr} /zImage
loadxfdt=echo debug: [/dtbs/\${fdtfile}] ... ;load mmc 0:1 \${fdtaddr} /dtbs/\${fdtfile}
check_cape=if test -n \${cape}; then setenv fdtfile \${fdtbase}-\${cape}.dtb;fi;
check_dtb=if test -n \${dtb}; then setenv fdtfile \${dtb};fi;
loadall=run check_cape; run check_dtb; run loadximage; run loadxfdt;

mmcargs=setenv bootargs console=tty0 console=\${console} \${optargs} \${cape_disable} \${cape_enable} root=/dev/mmcblk0p2 rootfstype=\${mmcrootfstype} \${cmdline}

uenvcmd=run loadall; run mmcargs; echo debug: [\${bootargs}] ... ; echo debug: [bootz \${loadaddr} - \${fdtaddr}] ... ; bootz \${loadaddr} - \${fdtaddr};
EOF
		if [ -e ${uenv_txt_install_path}/uEnv.txt ]; then
			if cmp ${uenv_txt_install_path}/uEnv.txt.new ${uenv_txt_install_path}/uEnv.txt --quiet; then
				# Files are the same, so no need to replace existing file
				rm ${uenv_txt_install_path}/uEnv.txt.new
			else
				# Files are different, so backup and replace existing file
				mv --backup=existing --suffix=.old ${uenv_txt_install_path}/uEnv.txt.new ${uenv_txt_install_path}/uEnv.txt
			fi
		else
			# File does not exist, so just move
			mv ${uenv_txt_install_path}/uEnv.txt.new ${uenv_txt_install_path}/uEnv.txt
		fi
	fi
else
	echo "CROSS COMPILING KERNEL"
	make ${make_args} $@

	for arg in "$@"
	do
		# If cleaning, remove the files generated by this script too.
		if [ "$arg" = "clean" -o "$arg" = "mrproper" -o "$arg" = "distclean" ]
		then
			rm -rf kernel
		fi
	done
fi