# Maintainer: Milan P. Stanić <mps@arvanta.net>

_flavor=edge
pkgname=linux-${_flavor}
# NOTE: this kernel is intended for testing
# please resist urge to upgrade it blindly
pkgver=5.13.8
case $pkgver in
	*.*.*)	_kernver=${pkgver%.*};;
	*.*) _kernver=$pkgver;;
esac
pkgrel=0
pkgdesc="Linux latest stable kernel"
url="https://www.kernel.org"
depends="mkinitfs"
_depends_dev="perl gmp-dev elfutils-dev bash flex bison"
makedepends="$_depends_dev sed installkernel bc linux-headers linux-firmware-any openssl-dev
	diffutils findutils xz"
options="!strip !check" # no tests
_config=${config:-config-edge.${CARCH}}
install=

subpackages="$pkgname-dev:_dev:$CBUILD_ARCH"
source="https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/linux-$_kernver.tar.xz"
case $pkgver in
	*.*.0)	source="$source";;
	*.*.*)	source="$source
	https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/patch-$pkgver.xz" ;;
esac

	source="$source
	config-edge.aarch64
	config-edge.armv7
	config-edge.x86_64
	config-edge.riscv64
	config-edge-virt.aarch64
	config-edge-virt.armv7
	config-edge-virt.x86_64
	config-edge-virt.riscv64
	"

arch="armv7 aarch64 x86_64 riscv64"
license="GPL-2.0"

_flavors=
for _i in $source; do
	case $_i in
	config-*.$CARCH)
		_f=${_i%.$CARCH}
		_f=${_f#config-}
		_flavors="$_flavors ${_f}"
		if [ "linux-$_f" != "$pkgname" ]; then
			subpackages="$subpackages linux-${_f}::$CBUILD_ARCH linux-${_f}-dev:_dev:$CBUILD_ARCH"
		fi
		;;
	esac
done

_carch=${CARCH}
case "$_carch" in
aarch64*) _carch="arm64" ;;
arm*) _carch="arm" ;;
riscv64) _carch="riscv" ;;
esac

prepare() {
	local _patch_failed=
	cd "$srcdir"/linux-$_kernver
	case $pkgver in
		*.*.0);;
		*)
		msg "Applying patch-$pkgver.xz"
		unxz -c < "$srcdir"/patch-$pkgver.xz | patch -p1 -N ;;
	esac

	# first apply patches in specified order
	for i in $source; do
		case $i in
		*.patch)
			msg "Applying $i..."
			if ! patch -s -p1 -N -i "$srcdir"/$i; then
				echo $i >>failed
				_patch_failed=1
			fi
			;;
		esac
	done

	if ! [ -z "$_patch_failed" ]; then
		error "The following patches failed:"
		cat failed
		return 1
	fi

	# remove localversion from patch if any
	rm -f localversion*
	oldconfig
}

oldconfig() {
	for i in $_flavors; do
		local _config=config-$i.${CARCH}
		local _builddir="$srcdir"/build-$i.$CARCH
		mkdir -p "$_builddir"
		echo "-$pkgrel-$i" > "$_builddir"/localversion-alpine \
			|| return 1

		cp "$srcdir"/$_config "$_builddir"/.config
		make -C "$srcdir"/linux-$_kernver \
			O="$_builddir" \
			ARCH="$_carch" \
			listnewconfig oldconfig
	done
}

build() {
	unset LDFLAGS
	export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"
	for i in $_flavors; do
		cd "$srcdir"/build-$i.$CARCH
		make ARCH="$_carch" CC="${CC:-gcc}" \
			KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-Alpine"
	done
}

_package() {
	local _buildflavor="$1" _outdir="$2"
	local _abi_release=${pkgver}-${pkgrel}-${_buildflavor}
	export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"

	cd "$srcdir"/build-$_buildflavor.$CARCH
	# modules_install seems to regenerate a defect Modules.symvers on s390x. Work
	# around it by backing it up and restore it after modules_install
	cp Module.symvers Module.symvers.backup

	mkdir -p "$_outdir"/boot "$_outdir"/lib/modules

	local _install
	case "$CARCH" in
		arm*|aarch64|riscv64) _install="zinstall dtbs_install";;
		*) _install=install;;
	esac

	make -j1 modules_install $_install \
		ARCH="$_carch" \
		INSTALL_MOD_PATH="$_outdir" \
		INSTALL_PATH="$_outdir"/boot \
		INSTALL_DTBS_PATH="$_outdir/boot/dtbs-$_buildflavor"

	cp Module.symvers.backup Module.symvers

	rm -f "$_outdir"/lib/modules/${_abi_release}/build \
		"$_outdir"/lib/modules/${_abi_release}/source
	rm -rf "$_outdir"/lib/firmware

	install -D -m644 include/config/kernel.release \
		"$_outdir"/usr/share/kernel/$_buildflavor/kernel.release
}

# main flavor installs in $pkgdir
package() {
	depends="$depends linux-firmware-any"

	_package edge "$pkgdir"
}

# subflavors install in $subpkgdir
virt() {
	_package edge-virt "$subpkgdir"
}

_dev() {
	local _flavor=$(echo $subpkgname | sed -E 's/(^linux-|-dev$)//g')
	local _abi_release=${pkgver}-${pkgrel}-$_flavor
	# copy the only the parts that we really need for build 3rd party
	# kernel modules and install those as /usr/src/linux-headers,
	# simlar to what ubuntu does
	#
	# this way you dont need to install the 300-400 kernel sources to
	# build a tiny kernel module
	#
	pkgdesc="Headers and script for third party modules for $_flavor kernel"
	depends="$_depends_dev"
	local dir="$subpkgdir"/usr/src/linux-headers-${_abi_release}
	export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"

	# first we import config, run prepare to set up for building
	# external modules, and create the scripts
	mkdir -p "$dir"
	cp "$srcdir"/config-$_flavor.${CARCH} "$dir"/.config
	echo "-$pkgrel-$_flavor" > "$dir"/localversion-alpine

	make -j1 -C "$srcdir"/linux-$_kernver O="$dir" ARCH="$_carch" \
		syncconfig prepare modules_prepare scripts

	# remove the stuff that points to real sources. we want 3rd party
	# modules to believe this is the soruces
	rm "$dir"/Makefile "$dir"/source

	# copy the needed stuff from real sources
	#
	# this is taken from ubuntu kernel build script
	# http://kernel.ubuntu.com/git/ubuntu/ubuntu-zesty.git/tree/debian/rules.d/3-binary-indep.mk
	cd "$srcdir"/linux-$_kernver
	find .  -path './include/*' -prune \
		-o -path './scripts/*' -prune -o -type f \
		\( -name 'Makefile*' -o -name 'Kconfig*' -o -name 'Kbuild*' -o \
		   -name '*.sh' -o -name '*.pl' -o -name '*.lds' -o -name 'Platform' \) \
		-print | cpio -pdm "$dir"

	cp -a scripts include "$dir"

	find $(find arch -name include -type d -print) -type f \
		| cpio -pdm "$dir"

	install -Dm644 "$srcdir"/build-$_flavor.$CARCH/Module.symvers \
		"$dir"/Module.symvers

	mkdir -p "$subpkgdir"/lib/modules/${_abi_release}
	ln -sf /usr/src/linux-headers-${_abi_release} \
		"$subpkgdir"/lib/modules/${_abi_release}/build
}

sha512sums="
a8edf97e9d38a49f1be2bde1e29ad96274bb2c6f7e8a2bebaa1161dd4df9cabcbaec4ff644c45bee94f86ae47725087d6deed0cd954209cec717621d137db85e  linux-5.13.tar.xz
8ecdcd19b0a1154796e3e31c600d45bcce1571f1c710affc3220d52622a56b3c6e2c6176c652d905b8c1647a21fd2f23f846f1a3103c3b74ca3bec5e467e3331  patch-5.13.8.xz
927216eba919c36f685c25be9df5326e4c926392cf3f357897a657bb4bc7e7ecc3a56cdacc451824fcd95ea48cfef425f24d23ad280fa3535581ae7dc822f394  config-edge.aarch64
1eccf1563e2cce12012d2fe9d90878e2d829a2b2fa4a322b389a8513ec0a4e8faa452c31ad304ee833226fc03b74ab1c15593f9c2de67de7faff8ffd02858087  config-edge.armv7
d05fca9dd16cd51c41434ab8b42215a7db90d766ed91366d5fe8f16342b567492a11860f0c1251dc135cfd5a055950419177c04f9cb631fb98d67e4a13f4425b  config-edge.x86_64
2b235e5be796ef2f7d08144d77638596dae035c6fd6c0b6f30797c65c932f4811e106104a1d8e3315b9d4952780d90d3d80a25b32bdd59ecb7e41518da5c3799  config-edge.riscv64
b12a1e288baab0455dbde64e93cac74f35a66ed1d2078233890ef751ac40afe7910ea89e5d59c00893bfad3f4aa1d4f69e8d80dd1771c7d1ebc06f4547bd2b9c  config-edge-virt.aarch64
7bdc2f0d5d88655a72ec593b9ac185875e6c10ca8411b874adc96c84d8cd281dba61d6f3b9cda28e96a850ad6e9cf65f21f35222a95d009c14aec57a0046362d  config-edge-virt.armv7
3d61afbe524fcfa3bc9aaeac50a3f6bdddca7f204d7f74b179549333d363d1aea789393d7f1de2919a6fe54957df6182fd2057704fdec24370508f5c4770db34  config-edge-virt.x86_64
2e47c7c724d24e16a50e68f6143391884ff9ab8f9f9e379cd2286dbbafa92477782b13bd6e82214402ce174a5f2429dedaef56dbcbeaf6d55438f81384a1167d  config-edge-virt.riscv64
"