# Reference: <https://postmarketos.org/vendorkernel>
# Kernel config based on: arch/arm/configs/tegra_defconfig

pkgname="linux-samsung-i927"
pkgver=4.20.4
pkgrel=0
pkgdesc="Samsung Captivate Glide kernel fork"
arch="armhf"
_carch="arm"
_flavor="samsung-i927"
url="https://kernel.org"
license="GPL-2.0-only"
options="!strip !check !tracedeps"
makedepends="perl sed installkernel bash gmp-dev bc linux-headers elfutils-dev devicepkg-dev flex bison openssl-dev"

# Compiler: latest GCC from Alpine
HOSTCC="${CC:-gcc}"
HOSTCC="${HOSTCC#${CROSS_COMPILE}}"

# Source
_repository="linux"
_config="config-${_flavor}.${arch}"
source="
	$pkgname-$pkgver.tar.gz::https://kernel.org/pub/linux/kernel/v4.x/linux-$pkgver.tar.gz
	$_config
	kernel.patch
"
builddir="$srcdir/${_repository}-${pkgver}"

prepare() {
	default_prepare

	# Prepare kernel config ('yes ""' for kernels lacking olddefconfig)
	cp "$srcdir/$_config" "$builddir"/.config
	yes "" | make -C "$builddir" ARCH="$_carch" HOSTCC="$HOSTCC" oldconfig
}

build() {
	unset LDFLAGS
	make ARCH="$_carch" CC="${CC:-gcc}" \
		KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-postmarketOS"
}

package() {
	cat "$builddir/arch/arm/boot/zImage" \
		"$builddir/arch/arm/boot/dts/tegra20-glide.dtb" \
		> "$builddir/arch/arm/boot/zImage-dtb"

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

	# zImage (find the right one)
	cd "$builddir/arch/$_carch/boot"
	_target="$pkgdir/boot/vmlinuz-$_flavor"
	for _zimg in zImage-dtb Image.gz-dtb *zImage Image; do
		[ -e "$_zimg" ] || continue
		msg "zImage found: $_zimg"
		install -Dm644 "$_zimg" "$_target"
		break
	done
	if ! [ -e "$_target" ]; then
		error "Could not find zImage in $PWD!"
		return 1
	fi

	cd "$builddir"
	make modules_install \
		ARCH="$_carch" \
		INSTALL_MOD_PATH="$pkgdir"
}

sha512sums="5f9eb065932e404091dd9e4afd5a92b6382ddbc81488684c42981cdfe227da9a423356c19ec236ca1a9a7f4bf042cf351aa8b3cd4f7488b0d8b1245d69221a5c  linux-samsung-i927-4.20.4.tar.gz
fb556670c376c85f6c0ad0105179298e8d7b1564e32c7a50152924112407dcc294b5e322eb207e801f61e81f9511e28c52dcd663152c2e5a1ea1a9e0100d09ba  config-samsung-i927.armhf
c65a89a07b20b3720d6187c6049f215823b07fd4ba647984691bf37d2488a71f4e00ce8bc9521c499b7e15f13fb1473289a8eeea42899d5a6c0c3247b0a94549  kernel.patch"