_flavor=postmarketos-lts
_config="config-${_flavor}.${CARCH}"

pkgname=linux-${_flavor}

pkgver=4.9.65
case $pkgver in
	*.*.*)	_kernver=${pkgver%.*};;
	*.*) _kernver=$pkgver;;
esac
pkgrel=3

arch="x86_64 armhf aarch64"
pkgdesc="Linux for pmOS supported chipsets (LTS)"
url="https://kernel.org/"
depends=""
makedepends="perl sed installkernel bash gmp-dev bc linux-headers elfutils-dev file"
options="!strip !check !tracedeps"
install=
source="
	https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/linux-$_kernver.tar.xz
	config-${_flavor}.armhf
	config-${_flavor}.aarch64
	config-${_flavor}.x86_64
"

if [ "${pkgver%.0}" = "$pkgver" ]; then
	source="$source
	https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/patch-$pkgver.xz"
fi
subpackages="$pkgname-dev"

license="GPL2"
_abi_release=${pkgver}
_carch=${CARCH}
case "$_carch" in
aarch64*) _carch="arm64" ;;
arm*) _carch="arm" ;;
ppc*) _carch="powerpc" ;;
s390*) _carch="s390" ;;
esac

HOSTCC="${CC:-gcc}"
HOSTCC="${HOSTCC#${CROSS_COMPILE}}"

ksrcdir="$srcdir/linux-$_kernver"

prepare() {
	local _patch_failed=
	cd "$ksrcdir"
	if [ "$_kernver" != "$pkgver" ]; then
		msg "Applying patch-$pkgver.xz"
		unxz -c < "$srcdir"/patch-$pkgver.xz | patch -p1 -N
	fi

	# 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

	mkdir -p "$srcdir"/build
	cp -v "$srcdir"/$_config "$srcdir"/build/.config
	make -C "$ksrcdir" O="$srcdir"/build ARCH="$_carch" HOSTCC="$HOSTCC" \
		olddefconfig
}



# this is so we can do: 'abuild menuconfig' to reconfigure kernel
menuconfig() {
	cd "$srcdir"/build
	make ARCH="$_carch" menuconfig
	cp .config "$startdir"/$_config
}

build() {
	cd "$srcdir"/build
	unset LDFLAGS
	make ARCH="$_carch" CC="${CC:-gcc}" \
		KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-postmarketOS" \
		CFLAGS_MODULE=-fno-pic
}

package() {
	cd "$srcdir/build/arch/${_carch}/boot"

	if [ "$CARCH" == "aarch64" ]; then
		install -Dm644 "$srcdir/build/arch/${_carch}/boot/Image" \
			"$pkgdir/boot/vmlinuz-$_flavor"
	else
		install -Dm644 "$srcdir/build/arch/${_carch}/boot/"*zImage \
			"$pkgdir/boot/vmlinuz-$_flavor"
	fi

	install -D "$srcdir/build/include/config/kernel.release" \
		"$pkgdir/usr/share/kernel/$_flavor/kernel.release"

	cd "$srcdir"/build

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

	make -j1 $_install \
		ARCH="$_carch" \
		INSTALL_MOD_PATH="$pkgdir" \
		INSTALL_DTBS_PATH="$pkgdir/usr/share/dtb"
}


dev() {
	# 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 postmarketos kernel"
	depends="gmp-dev bash perl"
	local dir="$subpkgdir"/usr/src/linux-headers-${_abi_release}

	# first we import config, run prepare to set up for building
	# external modules, and create the scripts
	mkdir -p "$dir"
	cp "$srcdir"/$_config "$dir"/.config
	make -j1 -C "$srcdir"/linux-$_kernver O="$dir" ARCH="$_carch" HOSTCC="$HOSTCC" \
		olddefconfig prepare modules_prepare scripts

	# needed for 3rd party modules
	# https://bugzilla.kernel.org/show_bug.cgi?id=11143
	case "$CARCH" in
	ppc*) (cd "$dir" && make arch/powerpc/lib/crtsavres.o);;
	esac

	# 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 \
		\( -name 'Makefile*' -o -name 'Kconfig*' -o -name 'Kbuild*' -o \
		   -name '*.sh' -o -name '*.pl' -o -name '*.lds' \) \
		-print | cpio -pdm "$dir"
	cp -a scripts include "$dir"
	find $(find arch -name include -type d -print) -type f \
		| cpio -pdm "$dir"

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

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

	# cross-compiling: delete binaries with host arch and replace them with
	# symlinks to binaries with the target arch (packaged in kernel-scripts)
	if [ -n "$CROSS_COMPILE" ]; then
		msg "Symlinking binary scripts..."
		depends="$depends kernel-scripts"
		cd "$dir/scripts"
		local i
		for i in $(find . -type f); do
			local type="$(file -b --mime-type "$i")"
			[ "$type" != "application/x-sharedlib" ] && continue
			local native="/usr/bin/kernel-scripts/$(echo "$i" | cut -d '/' -f 2-)"
			ln -svf "$native" "$i"
		done
	fi
}

sha512sums="bf67ff812cc3cb7e5059e82cc5db0d9a7c5637f7ed9a42e4730c715bf7047c81ed3a571225f92a33ef0b6d65f35595bc32d773356646df2627da55e9bc7f1f1a  linux-4.9.tar.xz
7de482169eb64cca001c298091471d803421dfef5835fa9a693840bd96083bdc42bc12a5217ececb5780ac285cf23674f2bd008183e651b81a7fc2882b819f01  config-postmarketos-lts.armhf
f7dcf05c3c3042c6105748bcbe60ff8c02fac91c7de260a51b568c983df7f2a69c2bde6ebc3ddc4b7283e4aba7e1a8b0e9e4baff6ab863553dc3767679f54f62  config-postmarketos-lts.aarch64
d1e6ca8faee80641a2e882b3b9b0009b05a73adee8e939ace17be7879f8a87f4f2e7cb7bbbb9590e9b6c1491ed076505dbef599c0dc9e71fe71a8d451a7b635e  config-postmarketos-lts.x86_64
f22ec263901248adb0b660e5ea6f9c550f28f53dcd27d4a5148a932bce3b92f91cd921ff1d62096ac78c235e7abbeafa7ae33fc4f042e7d876e1fd58945554ce  patch-4.9.65.xz"