shared/config/grub.cfg

# Root grub.cfg used either to boot raw kernel and/or initramfs.img, or to
# chain to an installed distro's GRUB configuration file

# These options are accessible to chain-loaded configurations as well:
#
# pnpacpi=off      Disable on QEMU; allows serdev to claim platform serial
# acpi=noirq       Do not configure IRQ routing using ACPI tables
# reboot=k         Reboot using keyboard method, rather than ACPI
# noexec=off       Some kernels panic when setting up NX
# noefi            Some kernels panic when trying to use U-Boot EFI
# panic=-1         Don't reboot on panic
# console=hvc0     Switch kernel logging to virtio-console once available
# console=ttyAMA0  QEMU on ARM64 uses alternative serial implementation
#
if [ "$grub_cpu" = "i386" ]; then
  set cmdline="pnpacpi=off acpi=noirq reboot=k noexec=off console=ttyS0 noefi panic=-1 console=hvc0"
elif [ "$grub_cpu" = "arm64" ]; then
  set cmdline="console=ttyS0 console=ttyAMA0 noefi panic=-1 console=hvc0"
else
  echo "Warning: No architecture found for ${grub_cpu}"
fi

# Root filesystem is on a GUID partition with label "otheros_root"
set rootfs="/dev/vda14"

# Root filesystem with grub installed
search --file --set root /boot/grub/grub.cfg --hint (hd0)
if [ $? = 0 ]; then
  set prefix=($root)/boot/grub
  export cmdline
  export rootfs
  configfile $prefix/grub.cfg
  normal_exit
fi

# Fall back if we couldn't chain to another GRUB install
set timeout=0
menuentry "Linux" {
  linux /vmlinuz $cmdline root=$rootfs
  if [ -e /initrd.img ]; then
    initrd /initrd.img
  fi
}