# AArch64 Apple Silicon (Aurora Silicon)
# Based on the asahi-alarm linux-asahi package by Jos Dehaes and Matthias Kurz.
#
# Aurora Silicon maintain a fork of the Asahi kernel carrying DisplayPort
# alt-mode and USB4 support for external monitors, variable refresh rate, and
# the ISP and AOP drivers. Those changes touch device trees, the type-C stack
# and DRM, so they cannot ship as a module: this is a whole alternative kernel
# for Macs on the Omarchy edge channel. It reaches rc and stable only after
# cold-boot qualification on M1 and M2.

_auroraver=7.1.12
_aurorarel=2
pkgrel=11

# Immutable pin on aurora-silicon/linux (branch aurora-wip). Every bump is a
# PR that moves _commit and the archive checksum; the pinned commit is cold-boot
# qualified on MacBook Pro 14" M1 Pro (j314s) and 16" M2 Max (j416c) first.
_commit=2439016d2e8d3a0d8aebcd243f29604a91f201c9

_m1n1_version=1.6.1

pkgbase=linux-aurora
_srcname=linux-${_commit}
_kernelname=${pkgbase#linux}
_desc="AArch64 Apple Silicon (Aurora kernel)"
pkgver="${_auroraver}.aurora${_aurorarel}"
arch=('aarch64')
url="https://github.com/aurora-silicon/linux"
license=('GPL2')

makedepends=(
  base-devel bc dtc kmod libelf pahole cpio perl rustup rust-bindgen tar xz xmlto python
)
options=('!strip')
source=(
  https://github.com/aurora-silicon/linux/archive/${_commit}.tar.gz
  config         # the main kernel config file
  rust-toolchain.toml
)
sha256sums=('6347354537148120fc5448afcb8671a558ce336f731c70690cd88062a903f84d'
            'e8f3818e6bfa70166dd5caff228a0becfdd5d4f0165b589efa38150fd0b59cc9'
            '2a95563bb9f5b216cc3c170a17e9471448bc63a7084bdd67df23d074939b366c')

# Kbuild takes ARCH literally and knows arm64, not aarch64.
export ARCH=arm64
export KBUILD_BUILD_HOST=archlinux
export KBUILD_BUILD_USER=$pkgbase
export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"

prepare() {
  cd $_srcname

  echo "Setting version..."
  echo "-$_aurorarel-$pkgrel" > localversion.10-pkgrel

  local src
  for src in "${source[@]}"; do
    src="${src%%::*}"
    src="${src##*/}"
    [[ $src = *.patch ]] || continue
    echo "Applying patch $src..."
    patch -Np1 < "../$src"
  done

  echo "Pinning the Rust toolchain..."
  cp ../rust-toolchain.toml .

  echo "Creating build directories..."
  mkdir -p build/base

  echo "Setting config (base)..."
  cp ../config build/base/.config
  make olddefconfig prepare O=$PWD/build/base
  diff -u ../config build/base/.config || :
  make -s kernelrelease O=$PWD/build/base > build/base/version

  echo "Prepared $pkgbase version $(<build/base/version)"
}

build() {
  cd $_srcname
  echo "Building base..."
  make all O=$PWD/build/base -j $(nproc)
}

_package_kernel() {
  pkgdesc="The $pkgdesc kernel and modules"
  depends=(coreutils kmod initramfs $2 "m1n1>=$_m1n1_version")
  optdepends=('crda: to set the correct wireless channels of your country'
              'linux-firmware: firmware images needed for some devices')
  # No generic linux provide: on a shared aarch64 repository it would compete
  # with linux-aarch64 for any dependency on linux.
  provides=(WIREGUARD-MODULE linux-asahi=${pkgver})
  conflicts=(linux-asahi)

  local kernver="$(<$O/version)"
  local modulesdir="$pkgdir/usr/lib/modules/$kernver"

  echo "Installing boot image..."
  # systemd expects to find the kernel here to allow hibernation
  # https://github.com/systemd/systemd/commit/edda44605f06a41fb86b7ab8128dcf99161d2344
  install -Dm644 "$O"/arch/arm64/boot/Image "$modulesdir/vmlinuz"

  # Used by mkinitcpio to name the kernel
  echo "$1" | install -Dm644 /dev/stdin "$modulesdir/pkgbase"

  echo "Installing modules..."
  make O="$O" INSTALL_MOD_PATH="$pkgdir/usr" INSTALL_MOD_STRIP=1 modules_install

  echo "Installing device trees..."
  install -Dt "$modulesdir/dtbs" "$O"/arch/arm64/boot/dts/apple/*.dtb

  # remove build and source links
  rm -f "$modulesdir"/{source,build}
}

_package() {
  cd $_srcname
  export O="$PWD/build/base"
  _package_kernel "$pkgbase"
}

_package-headers() {
  pkgdesc="Headers and scripts for building modules for the $pkgdesc kernel"
  depends=(pahole)
  provides=(linux-asahi-headers=${pkgver})
  conflicts=(linux-asahi-headers)

  KARCH=arm64

  cd $_srcname
  O=build/base
  local builddir="$pkgdir/usr/lib/modules/$(<${O}/version)/build"

  echo "Installing build files..."
  install -Dt "$builddir" -m644 $O/.config Makefile $O/Module.symvers $O/System.map \
    localversion.* $O/version $O/vmlinux
  install -Dt "$builddir/kernel" -m644 kernel/Makefile
  cp -t "$builddir" -a scripts $O/scripts

  # required when STACK_VALIDATION is enabled
  #install -Dt "$builddir/tools/objtool" tools/objtool/objtool

  # required when DEBUG_INFO_BTF_MODULES is enabled
  install -Dt "$builddir/tools/bpf/resolve_btfids" $O/tools/bpf/resolve_btfids/resolve_btfids

  echo "Installing headers..."
  cp -t "$builddir" -a include $O/include

  install -Dt "${builddir}/arch/${KARCH}" -m644 arch/${KARCH}/Makefile
  install -Dt "${builddir}/arch/${KARCH}/kernel" -m644 $O/arch/${KARCH}/kernel/asm-offsets.s
  cp -t "${builddir}/arch/${KARCH}" -a arch/${KARCH}/include $O/arch/${KARCH}/include

  install -Dt "$builddir/drivers/md" -m644 drivers/md/*.h
  install -Dt "$builddir/net/mac80211" -m644 net/mac80211/*.h

  # https://bugs.archlinux.org/task/13146
  install -Dt "$builddir/drivers/media/i2c" -m644 drivers/media/i2c/msp3400-driver.h

  # https://bugs.archlinux.org/task/20402
  install -Dt "$builddir/drivers/media/usb/dvb-usb" -m644 drivers/media/usb/dvb-usb/*.h
  install -Dt "$builddir/drivers/media/dvb-frontends" -m644 drivers/media/dvb-frontends/*.h
  install -Dt "$builddir/drivers/media/tuners" -m644 drivers/media/tuners/*.h

  # https://bugs.archlinux.org/task/71392
  install -Dt "$builddir/drivers/iio/common/hid-sensors" -m644 drivers/iio/common/hid-sensors/*.h

  echo "Installing KConfig files..."
  find . -name 'Kconfig*' -exec install -Dm644 {} "$builddir/{}" \;

  echo "Installing unstripped VDSO..."
  make O="$O" INSTALL_MOD_PATH="$pkgdir/usr" vdso_install link=

  echo "Removing unneeded architectures..."
  local arch
  for arch in "$builddir"/arch/*/; do
    [[ $arch = */${KARCH}/ ]] && continue
    echo "Removing $(basename "$arch")"
    rm -r "$arch"
  done

  echo "Removing documentation..."
  rm -r "$builddir/Documentation"

  echo "Removing broken symlinks..."
  find -L "$builddir" -type l -printf 'Removing %P\n' -delete

  echo "Removing loose objects..."
  find "$builddir" -type f -name '*.o' -printf 'Removing %P\n' -delete

  echo "Removing cmd files..."
  find "$builddir" -type f -name '*.cmd' -printf 'Removing %P\n' -delete

  echo "Stripping build tools..."
  local file
  while read -rd '' file; do
    case "$(file --no-sandbox -bi "$file")" in
      application/x-sharedlib\;*)      # Libraries (.so)
        strip -v $STRIP_SHARED "$file" ;;
      application/x-archive\;*)        # Libraries (.a)
        strip -v $STRIP_STATIC "$file" ;;
      application/x-executable\;*)     # Binaries
        strip -v $STRIP_BINARIES "$file" ;;
      application/x-pie-executable\;*) # Relocatable binaries
        strip -v $STRIP_SHARED "$file" ;;
    esac
  done < <(find "$builddir" -type f -perm -u+x ! -name vmlinux -print0)

  echo "Stripping vmlinux..."
  strip -v $STRIP_STATIC "$builddir/vmlinux"

  echo "Adding symlink..."
  mkdir -p "$pkgdir/usr/src"
  ln -sr "$builddir" "$pkgdir/usr/src/$pkgbase"

}

pkgname=("$pkgbase" "$pkgbase-headers")
for _p in "${pkgname[@]}"; do
  eval "package_$_p() {
    $(declare -f "_package${_p#$pkgbase}")
    _package${_p#$pkgbase}
  }"
done

# vim:set ts=8 sts=2 sw=2 et: