mk-sd-image

#!/bin/bash

set -e
cd -P `dirname $0`

SD_SIZE=1500
SD_BOOT_SIZE=64
SD_SWAP_SIZE=
SD_IMG=debian-riscv64/debian-riscv64.sd.img
RSYNC_BOOT=

while getopts r:s:b:p:i: name ; do
  case $name in
  r)
    RSYNC_BOOT=$OPTARG
    ;;
  s)
    SD_SIZE=$OPTARG
    ;;
  b)
    SD_BOOT_SIZE=$OPTARG
    ;;
  p)
    SD_SWAP_SIZE=$OPTARG
    ;;
  i)
    SD_IMG=$OPTARG
    ;;
  esac
done

if [ ! -d linux-stable/kernel ] ; then
  make update-submodules
fi

KERNEL_VER=$(cd linux-stable && git describe --exact-match --abbrev=0)

# --- Retrive Debian disk image ---

make debian-riscv64/initrd debian-riscv64/rootfs.tar.gz

# --- Build BBL and Linux ---

if [ ! -f workspace/boot.elf ] ; then
  make bootloader -j
fi
if [ ! -f linux-stable/arch/riscv/boot/Image ] ; then
  make linux -j
fi

# --- build SD card image ---

mount -l | grep `pwd`/ | while IFS=' ' read -ra LINE ; do
  sudo umount ${LINE[0]}
done
losetup -a | grep `pwd`/ | while IFS=':' read -ra LINE ; do
  sudo losetup -d ${LINE[0]}
done
losetup -a | grep `pwd`/ | while IFS=':' read -ra LINE ; do
  echo "Cannot detach ${LINE[*]}"
  exit 1
done

rm -f $SD_IMG
dd if=/dev/zero of=$SD_IMG bs=1M count=$SD_SIZE
SD_LOOP=$(sudo losetup --find --partscan --show $SD_IMG)
echo "SD image device: ${SD_LOOP}"

sudo sfdisk ${SD_LOOP} <<-__EOF__
1M,${SD_BOOT_SIZE}M,0xE,*
,,,-
__EOF__

sudo partprobe ${SD_LOOP}

UUID=68d82fa1-1bb5-435f-a5e3-862176586eec
sudo mkfs.vfat -F 16 -n BOOT ${SD_LOOP}p1
sudo mkfs.ext4 -E nodiscard -L rootfs -U $UUID ${SD_LOOP}p2

cat >debian-riscv64/extlinux.conf <<EOF
menu title RISC-V Boot Options.
timeout 50
default Debian $KERNEL_VER
label Debian $KERNEL_VER
 kernel /extlinux/image-$KERNEL_VER
 initrd /extlinux/initrd-$KERNEL_VER.img
 append ro root=UUID=$UUID earlycon initramfs.runsize=24M locale.LANG=en_US.UTF-8
EOF

mkdir -p debian-riscv64/boot
mkdir -p debian-riscv64/rootfs

sudo mount ${SD_LOOP}p1 debian-riscv64/boot
sudo mount ${SD_LOOP}p2 debian-riscv64/rootfs

pushd debian-riscv64/rootfs
  if [ -z "$SD_SWAP_SIZE" ] ; then
    sudo tar xzf ../rootfs.tar.gz
  else
    sudo tar --exclude=swapfile -xzf ../rootfs.tar.gz
    sudo fallocate -l ${SD_SWAP_SIZE}M swapfile
    sudo chmod 600 swapfile
    sudo mkswap swapfile
  fi
popd

pushd debian-riscv64/boot
  sudo mkdir extlinux
  sudo cp ../extlinux.conf extlinux
  sudo cp ../initrd extlinux/initrd-$KERNEL_VER.img
  sudo cp ../../linux-stable/arch/riscv/boot/Image extlinux/image-$KERNEL_VER
  sudo cp ../../workspace/boot.elf boot.elf
popd

sudo chown root:root debian-riscv64/rootfs
sudo chmod 755 debian-riscv64/rootfs

echo
echo "Boot partition:"
df debian-riscv64/boot
ls -l debian-riscv64/boot
echo
echo "Root partition:"
df debian-riscv64/rootfs
ls -l debian-riscv64/rootfs
echo

if [ ! -z "$RSYNC_BOOT" ] ; then
  rsync -r --delete debian-riscv64/boot/ $RSYNC_BOOT
fi

# According to docs, don't need to run sync before umount.
# umount will complete all pending writes before it actually unmounts the filesystem.
# In reality, without sync, VFAT filesystem sometimes gets corrupted after umount.
# Must be a Linux bug.
sync


umount_with_retry() {
    local device=$1
    local max_attempts=3
    local attempt=1

    while [ $attempt -le $max_attempts ]; do
        sudo umount -l $device
        if ! mount | grep -q $device; then
            echo "$device successfully unmounted."
            return 0
        else
            echo "Unmount attempt $attempt for $device failed. Retrying in 1 second..."
            sleep 1
            attempt=$((attempt + 1))
        fi
    done

    echo "Failed to unmount $device after $max_attempts attempts."
    return 1
}

# Unmount partitions
umount_with_retry ${SD_LOOP}p1 || exit 1
umount_with_retry ${SD_LOOP}p2 || exit 1


sudo fsck -f -p -T ${SD_LOOP}p1 || true
sudo fsck -f -p -T ${SD_LOOP}p2
sudo losetup -d ${SD_LOOP}