# Maintainer: Natanael Copa <ncopa@alpinelinux.org>

pkgname=linux-rpi
pkgver=4.9.76
case $pkgver in
*.*.*)	_kernver=${pkgver%.*};;
*.*)	_kernver=${pkgver};;
esac
pkgrel=0
pkgdesc="Linux kernel with Raspberry Pi patches"
url=https://github.com/raspberrypi/linux
depends="mkinitfs linux-firmware"
makedepends="perl installkernel bash gmp-dev bc"
options="!strip"
install=
# rpi patches are git diff against latest release tag from:
# linux-4.9.y       https://github.com/raspberrypi/linux/tree/rpi-4.9.y
source="https://kernel.org/pub/linux/kernel/v4.x/linux-$_kernver.tar.xz
	https://kernel.org/pub/linux/kernel/v4.x/patch-$pkgver.xz
	https://dev.alpinelinux.org/archive/rpi-patches/rpi-4.9.63-alpine.patch
	gpio-mcp23s08-pullups.patch
	issue-4973.patch

	config-rpi.armhf
	config-rpi2.armhf
	markdt
	"
subpackages=""
_flavors=
for _i in $source; do
	case $_i in
	config-*.$CARCH)
		_f=${_i%.$CARCH}
		_f=${_f#config-}
		_flavors="$_flavors ${_f}"
		[ "linux-$_f" != "$pkgname" ] && subpackages="$subpackages linux-${_f}"
		subpackages="$subpackages linux-${_f}-dev:_dev"
		;;
	esac
done

arch="armhf"
license="GPL-2.0"

prepare() {
	local _patch_failed=
	cd "$srcdir"/linux-$_kernver
	if [ "${pkgver%.0}" = "$pkgver" ]; then
		msg "Applying patch-$pkgver.xz"
		unxz -c < "$srcdir"/patch-$pkgver.xz | patch -p1 -N || return 1
	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

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

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

		cp "$srcdir"/$_config "$_builddir"/.config || return 1
		make -C "$srcdir"/linux-$_kernver \
			O="$_builddir" \
			HOSTCC="${CC:-gcc}" \
			silentoldconfig || return 1
	done
}

build() {
	for i in $_flavors; do
		cd "$srcdir"/build-$i
		make CC="${CC:-gcc} -fno-pie" \
			KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-Alpine" \
			|| return 1
	done
}

_package() {
	local _buildflavor="$1" _outdir="$2"
	local _abi_release=${pkgver}-${pkgrel}-${_buildflavor}

	cd "$srcdir"/build-$_buildflavor || return 1

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

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

	cd "$srcdir"/build-$_buildflavor || return 1
	make -j1 modules_install firmware_install $_install \
		INSTALL_MOD_PATH="$_outdir" \
		INSTALL_PATH="$_outdir"/boot \
		INSTALL_DTBS_PATH="$_outdir"/usr/lib/linux-${_abi_release} \
		|| return 1

	# tell rpi bootloader we are device tree capable
	"$srcdir"/markdt "$_outdir"/boot/vmlinuz-$_buildflavor \
		|| return 1

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

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

# main flavor installs in $pkgdir
package() {
	_package rpi "$pkgdir"
}

# subflavors install in $subpkgdir
rpi2() {
	_package rpi2 "$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 $_flavor kernel"
	depends="gmp-dev bash"
	local dir="$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-$_flavor.${CARCH} "$dir"/.config
	make -j1 -C "$srcdir"/linux-$_kernver O="$dir" HOSTCC="${CC:-gcc}" \
		silentoldconfig 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 \
		\( -name 'Makefile*' -o -name 'Kconfig*' -o -name 'Kbuild*' -o \
		   -name '*.sh' -o -name '*.pl' -o -name '*.lds' \) \
		-print | cpio -pdm "$dir" || return 1

	cp -a scripts include "$dir" || return 1
	find $(find arch -name include -type d -print) -type f \
		| cpio -pdm "$dir"

	install -Dm644 "$srcdir"/build-$_flavor/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="bf67ff812cc3cb7e5059e82cc5db0d9a7c5637f7ed9a42e4730c715bf7047c81ed3a571225f92a33ef0b6d65f35595bc32d773356646df2627da55e9bc7f1f1a  linux-4.9.tar.xz
57d98aa04f01a7ff550885b42cbd115b81234994005378bace5d984dfec232039934c64bff14fd88a5ba962c6dacf5b408173cccf551eb1195f0be980bb41090  patch-4.9.76.xz
31c665e1ce6f78f2322891e13db1b3712884082dedf5bdf056b83b7207feaecde5bdf5ffda145275e10c17e1e221be78aed8d50a7cf581378537f7e7346de3cd  rpi-4.9.63-alpine.patch
36724ba56cb8fdf3a3d347cffb67ae1cc3d7b1052d526b6b5134ebf6baae9f9724b586c97833453dc7697ab24699426f0749af78b6a80be36967a80033a0cf40  gpio-mcp23s08-pullups.patch
501c91bf2538a18102da59bbccc3097f9c3c90079acc0e946ff075074160c09b8a66934e5ce5470e170f0e4f93d114709a95230367426d0bb7ea02c4bdf4cc9b  issue-4973.patch
dd84624bedfd624d7051d833241b83b96d4c4b9943e7969130ec35cdd86a35b98fc2ebd48d84ddb97115ebfb9a59b84b3b01ea48aca78ae8f8ad8d534f8b36fa  config-rpi.armhf
031ce381e602f37bfab73e774475b1f323945b59d83c2177e63ce77b3d7ca2119e67d48f1a79b51bf66412c8ebf75353b71d400c6a1efb9d6c3ca4665f5c017d  config-rpi2.armhf
a8e7f434c325c9dd7a9109efecad408e42a50ecd1391cb0c7d1d7de79609caee007486c8a6538231c74bdc5d7b84cbca053958e1b239bc0507e6d3598ace383a  markdt"
