#!/bin/bash
#
# linux kernel CROSS make wrapper
#
# It will download/unpack the cross tool chain if necessary,
# then invoke make with suitable options.
#
# It detects ARCH in 4 ways.
#
# - make.i386 # make it a symlink to this script
# - make.cross ARCH=i386
# - cd obj-i386; make.cross
# - export ARCH=i386; make.cross
#
# Specify compiler and version (default is gcc):
# - COMPILER=gcc-9.3.0 make.cross ARCH=arm64
# - COMPILER=clang make.cross ARCH=arm64
#
# Copyright (c) 2014, Intel Corporation.
# Author: Fengguang Wu <fengguang.wu@intel.com>
# Credit: Tony Breeds <tony@bakeyournoodle.com> for crosstool

COMPILER=${COMPILER:-"gcc"}

if [[ ! "$0" =~ 'make.cross' && "$0" =~ make\.([a-z0-9_]+) ]]; then
	export ARCH="${BASH_REMATCH[1]}"
elif [[ "$*" =~ ARCH=([a-z0-9_]+) ]]; then
	export ARCH="${BASH_REMATCH[1]}"
elif [[ ${PWD##*-} =~ ^(i386|x86_64|alpha|arc|arm|arm64|avr32|blackfin|c6x|cris|frv|h8300|hexagon|ia64|m32r|m68k|microblaze|mips|mn10300|openrisc|parisc|powerpc|s390|score|sh|sh64|sparc|sparc32|sparc64|tile|tilepro|tilegx|um|unicore32|xtensa)$ ]]; then
	export ARCH=${PWD##*-}
elif [[ ! $ARCH ]]; then
	export ARCH=x86_64
fi

[[ "$*" =~ ARCH=([a-z0-9_]+) ]] && [[ $ARCH != ${BASH_REMATCH[1]} ]] && {
	echo "Conflicting ARCH specified! $ARCH ${BASH_REMATCH[1]}"
	exit 1
}

shopt -s nullglob

is_clang_worker()
{
	[[ "$COMPILER" =~ "clang" ]]
}

check_install_path()
{
	if [[ $COMPILER_INSTALL_PATH ]]; then
		echo "Compiler will be installed in $COMPILER_INSTALL_PATH"
	else
		return 1
	fi

}

install_packages()
{
	[[ -x /usr/bin/xz && -x /usr/bin/lftp ]] || {
		echo Please install: xz-utils lftp
		return 1
	}
}

download_extract()
{
	local URL="$1"
	local file="$(basename $URL)"
	local dir="$(basename $(dirname $URL))"

	mkdir -p $dir || return
	cd $dir

	echo lftpget -c $URL
	     lftpget -c $URL || return
	cd ..

	mkdir -p $COMPILER_INSTALL_PATH || return

	[[ -w "$COMPILER_INSTALL_PATH" ]] || {
		echo "Can't use $COMPILER_INSTALL_PATH as compiler install path, please choose a different COMPILER_INSTALL_PATH"
		return 1
	}

	echo tar Jxf $dir/$file -C $COMPILER_INSTALL_PATH
	tar Jxf $dir/$file -C $COMPILER_INSTALL_PATH
}

install_crosstool_clang()
{
	local URL='https://download.01.org/0day-ci/cross-package'
	local list=/tmp/0day-ci-crosstool-files
	local file='clang.tar.xz'
	lftp -c "open $URL && find -d 3 > $list" || return

	file=$(grep $file $list | tail -1)
	[[ $file ]] || {
		echo "Cannot find $file under $URL check $list"
		return 1
	}

	rm $list

	download_extract "$URL/$file" || {
		echo "Failed to download $URL/$file"
		return 1
	}
}

install_crosstool_gcc()
{
	local URL='https://download.01.org/0day-ci/cross-package'
	local list=/tmp/0day-ci-crosstool-files

	lftp -c "open $URL && find -d 3 > $list" || return

	local file
	local gcc_arch_pattern=$(echo "${gcc_arch}" | sed 's/*/.*/g')

	local gcc_version
	[[ $COMPILER =~ - ]] && gcc_version=${COMPILER##*-}
	if [[ $gcc_version ]]; then
		# for arch has more than 1 cross tool available, like x86_64-gcc-9.3.0-nolibc_arm-linux-gnueabi.tar.xz
		# and x86_64-gcc-9.3.0-nolibc_arm-linux-gnueabihf.tar.xz for arm, match "arm-linux-gnueabi." instead of
		# "arm-linux-gnueabi" to get single tool package which match exactly.
		file=$(grep "${gcc_arch_pattern}\." $list | grep "${gcc_version}" | tail -1)
	else
		file=$(grep "${gcc_arch_pattern}\." $list | tail -1)
	fi
	[[ $file ]] || {
		echo "Cannot find $gcc_arch_pattern under $URL check $list"
		return 1
	}

	rm $list

	download_extract "$URL/$file" || {
		echo "Failed to download $URL/$file"
		return 1
	}
}

install_crosstool()
{
	if is_clang_worker; then
		install_crosstool_clang || {
			echo "clang crosstool install failed"
			return 1
		}
	else
		install_crosstool_gcc || {
			echo "gcc crosstool install failed"
			return 1
		}
	fi
}

install_cross_compiler()
{
	install_packages && install_crosstool
}

setup_compiler_for_xtensa()
{
	local variant

	variant=$(grep -s -h '^CONFIG_XTENSA_VARIANT_CUSTOM_NAME=' .config |
		  head -n1 |
		  cut -f2 -d'"')

	if [[ "$variant" = 'fsf' ]]; then
		gcc_arch=$ARCH-linux
	elif [[ $variant ]]; then
		gcc_arch=xtensa-${variant}-linux
	else
		gcc_arch=$ARCH-linux
	fi
}

setup_crosstool_gcc()
{
	local gcc_arch
	local gcc_exec

	case $ARCH in
		i386|x86_64)
			gcc_arch=
			;;
		arc|c6x)
			gcc_arch=$ARCH-elf
			;;
		um)
			gcc_arch=
			;;
		arm)
			gcc_arch=arm-linux-gnueabi
			;;
		arm64)
			gcc_arch=aarch64-linux*
			;;
		powerpc)
			gcc_arch=powerpc64-linux
			;;
		blackfin)
			gcc_arch=bfin-uclinux
			;;
		sh)
			gcc_arch=sh4-linux
			;;
		parisc)
			if grep -s -q 'CONFIG_64BIT=y' $SRC_ROOT/arch/parisc/configs/$config; then
				gcc_arch=hppa64-linux
			else
				gcc_arch=hppa-linux
			fi
			;;
		openrisc)
			gcc_arch=or1k-linux
			;;
		riscv)
			gcc_arch=riscv64-linux
			;;
		s390)
			gcc_arch=s390-linux
			;;
		tile|tilegx)
			gcc_arch=tilegx-linux
			;;
		mn10300)
			gcc_arch=am33_2.0-linux
			;;
		nds32)
			gcc_arch=nds32le-linux
			;;
		xtensa)
			setup_compiler_for_xtensa
			;;
		*)
			gcc_arch=$ARCH-linux
			;;
	esac

	if [[ $gcc_arch ]]; then
		gcc_exec=($COMPILER_INSTALL_PATH/${COMPILER}*/${gcc_arch}/bin/${gcc_arch}-gcc)
		[[ -x $gcc_exec ]] || install_cross_compiler || {
			echo "Install gcc cross compiler failed"
			return 1
		}

		gcc_exec=($COMPILER_INSTALL_PATH/${COMPILER}*/${gcc_arch}/bin/${gcc_arch}-gcc)
		[[ -x $gcc_exec ]] || {
			echo "No cross compiler for $ARCH"
			return 1
		}

		# use highest available version
		gcc_exec=${gcc_exec[-1]}

		opt_cross="CROSS_COMPILE=${gcc_exec%gcc}"

		# load build-in depends libs
		local deplibs_path=($COMPILER_INSTALL_PATH/${COMPILER}*/${gcc_arch}/libexec/gcc/${gcc_arch}/*)
		deplibs_path=${deplibs_path[-1]}
		[[ -d $deplibs_path ]] && export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$deplibs_path

	else
		opt_cross=
	fi

	return 0
}

setup_crosstool_clang()
{
	local cross_clang=("$COMPILER_INSTALL_PATH"/clang-latest/bin/clang)
	[[ -x $cross_clang ]] || install_cross_compiler || {
		echo "Install clang compiler failed"
		return 1
	}

	local cross_clang_path=$(dirname $cross_clang)
	local opt_ldd="LD=${cross_clang_path}/ld.lld HOSTLD=${cross_clang_path}/ld.lld"
	[[ $ARCH =~ arm ]] &&
		grep -q 'CONFIG_CPU_BIG_ENDIAN=y' .config && opt_ldd=
	[[ $ARCH = s390 ]] && opt_ldd=

	# https://www.kernel.org/doc/html/latest/kbuild/llvm.html
	opt_cross="HOSTCC=$cross_clang CC=$cross_clang $opt_ldd \
		AR=${cross_clang_path}/llvm-ar NM=${cross_clang_path}/llvm-nm \
		STRIP=${cross_clang_path}/llvm-strip OBJDUMP=${cross_clang_path}/llvm-objdump \
		OBJSIZE=${cross_clang_path}/llvm-size READELF=${cross_clang_path}/llvm-readelf \
		HOSTCXX=${cross_clang_path}/clang++ HOSTAR=${cross_clang_path}/llvm-ar"
	if [[ $ARCH = "arm64" ]]; then
		opt_cross="$opt_cross CROSS_COMPILE=aarch64-linux-gnu-"
	elif [[ $ARCH = "arm" ]]; then
		opt_cross="$opt_cross CROSS_COMPILE=arm-linux-gnueabi-"
	elif [[ $ARCH = "s390" ]]; then
		opt_cross="$opt_cross CROSS_COMPILE=s390x-linux-gnu-"
	else
		opt_cross="$opt_cross CROSS_COMPILE=$ARCH-linux-gnu-"
	fi
}

setup_crosstool()
{
	if is_clang_worker; then
		setup_crosstool_clang
	else
		setup_crosstool_gcc
	fi
}

check_install_path || {
	echo "Please set COMPILER_INSTALL_PATH to specify compiler install path"
	echo "E.g. COMPILER_INSTALL_PATH=\$HOME/0day COMPILER=clang make.cross ARCH=x86_64"
	echo
	exit 1
}

setup_crosstool || {
	echo "setup_crosstool failed"
	exit 1
}

[[ "$*" =~ (-j|--jobs) ]] || {
	nr_cpu=$(getconf _NPROCESSORS_CONF)
	opt_jobs="--jobs=$((nr_cpu * 2))"
}

[[ "$*" =~ "ARCH=$ARCH" ]] || {
	opt_arch="ARCH=$ARCH"
}

if [ -d obj-$ARCH ]; then
	export KBUILD_OUTPUT=obj-$ARCH
	O=KBUILD_OUTPUT=obj-$ARCH
fi

[[ -f arch/$ARCH/boot/dts/Makefile ]] && make_dts="CONFIG_OF_ALL_DTBS=y CONFIG_DTC=y"

[[ -f .make-env ]] && source ./.make-env

if [[ -d source && -L source ]]; then
	echo make W=1 -C source O=$PWD $make_dts $opt_arch $opt_cross $subarch $opt_jobs "$@"
	exec make W=1 -C source O=$PWD $make_dts $opt_arch $opt_cross $subarch $opt_jobs "$@"
else
	echo make W=1 $O $make_dts $opt_arch $opt_cross $subarch $opt_jobs "$@"
	exec make W=1 $O $make_dts $opt_arch $opt_cross $subarch $opt_jobs "$@"
fi