#!/bin/sh

enable_serial_console() {
    # By default, spawn a console on the serial port
    device="$1"
    echo "Adding a getty on the serial port"
    echo "T0:12345:respawn:/sbin/getty -L $device 115200 vt100" >> /etc/inittab
}

beaglebone_setup_boot() {
    # Setup uEnv.txt
    if grep -q btrfs /etc/fstab ; then
        fstype=btrfs
    else
        fstype=ext4
    fi
    kernelVersion=$(ls /usr/lib/*/am335x-boneblack.dtb | head -1 | cut -d/ -f4)
    version=$(echo $kernelVersion | sed 's/linux-image-\(.*\)/\1/')
    initRd=initrd.img-$version
    vmlinuz=vmlinuz-$version

    # uEnv.txt for Beaglebone
    # based on https://github.com/beagleboard/image-builder/blob/master/target/boot/beagleboard.org.txt
    cat >> /boot/uEnv.txt <<EOF
mmcroot=/dev/mmcblk0p2 ro
mmcrootfstype=$fstype rootwait fixrtc
mmcrootflags=subvol=@

console=ttyO0,115200n8

kernel_file=$vmlinuz
initrd_file=$initRd

loadaddr=0x80200000
initrd_addr=0x81000000
fdtaddr=0x80F80000

initrd_high=0xffffffff
fdt_high=0xffffffff

loadkernel=load mmc \${mmcdev}:\${mmcpart} \${loadaddr} \${kernel_file}
loadinitrd=load mmc \${mmcdev}:\${mmcpart} \${initrd_addr} \${initrd_file}; setenv initrd_size \${filesize}
loadfdt=load mmc \${mmcdev}:\${mmcpart} \${fdtaddr} /dtbs/\${fdtfile}

loadfiles=run loadkernel; run loadinitrd; run loadfdt
mmcargs=setenv bootargs console=tty0 console=\${console} root=\${mmcroot} rootfstype=\${mmcrootfstype} rootflags=\${mmcrootflags}

uenvcmd=run loadfiles; run mmcargs; bootz \${loadaddr} \${initrd_addr}:\${initrd_size} \${fdtaddr}
EOF

    mkdir -p /boot/dtbs
    cp /usr/lib/linux-image-*-armmp/* /boot/dtbs
}

beaglebone_flash() {
    # allow flash-kernel to work without valid /proc contents
    # ** this doesn't *really* work, since there are too many checks
    #    that fail in an emulated environment!  We'll have to do it by
    #    hand below anyway...
    export FK_MACHINE="TI AM335x BeagleBone"
    apt-get install -y flash-kernel
}

beaglebone_repack_kernel() {
# process installed kernel to create uImage, uInitrd, dtb
# using flash-kernel would be a good approach, except it fails in the
# cross build environment due to too many environment checks...
#FK_MACHINE="TI AM335x BeagleBone" flash-kernel
#  so, let's do it manually...

# flash-kernel's hook-functions provided to mkinitramfs have the
# unfortunate side-effect of creating /conf/param.conf in the initrd
# when run from our emulated chroot environment, which means our root=
# on the kernel command line is completely ignored!  repack the initrd
# to remove this evil...

    echo "info: repacking beaglebone kernel and initrd"

    kernelVersion=$(ls /usr/lib/*/am335x-boneblack.dtb | head -1 | cut -d/ -f4)
    version=$(echo $kernelVersion | sed 's/linux-image-\(.*\)/\1/')
    initRd=initrd.img-$version
    vmlinuz=vmlinuz-$version

    mkdir /tmp/initrd-repack

    (cd /tmp/initrd-repack ; \
    zcat /boot/$initRd | cpio -i ; \
    rm -f conf/param.conf ; \
    find . | cpio --quiet -o -H newc | \
    gzip -9 > /boot/$initRd )

    rm -rf /tmp/initrd-repack

    (cd /boot ; \
    cp /usr/lib/$kernelVersion/am335x-boneblack.dtb dtb ; \
    cat $vmlinuz dtb >> temp-kernel ; \
    mkimage -A arm -O linux -T kernel -n "Debian kernel ${version}" \
    -C none -a 0x80200000 -e 0x80200000 -d temp-kernel uImage ; \
    rm -f temp-kernel ; \
    mkimage -A arm -O linux -T ramdisk -C gzip -a 0x81000000 -e 0x81000000 \
    -n "Debian ramdisk ${version}" \
    -d $initRd uInitrd )
}

cubieboard2_setup_boot() {
    # Setup boot.cmd
    if grep -q btrfs /etc/fstab ; then
        fstype=btrfs
    else
        fstype=ext4
    fi
    kernelVersion=$(ls /usr/lib/*/sun7i-a20-cubieboard2.dtb | head -1 | cut -d/ -f4)
    version=$(echo $kernelVersion | sed 's/linux-image-\(.*\)/\1/')
    initRd=initrd.img-$version
    vmlinuz=vmlinuz-$version

    # boot.cmd for CubieTruck
    cat >> /boot/boot.cmd <<EOF
setenv mmcdev 0
setenv mmcpart 1

setenv mmcroot /dev/mmcblk0p2 ro
setenv mmcrootfstype $fstype rootwait fixrtc
setenv mmcrootflags subvol=@

setenv console ttyS0,115200n8

setenv kernel_file $vmlinuz
setenv initrd_file $initRd

setenv loadaddr 0x46000000
setenv initrd_addr 0x48000000
setenv fdtaddr 0x47000000

setenv initrd_high 0xffffffff
setenv fdt_high 0xffffffff

setenv loadkernel load mmc \${mmcdev}:\${mmcpart} \${loadaddr} \${kernel_file}
setenv loadinitrd load mmc \${mmcdev}:\${mmcpart} \${initrd_addr} \${initrd_file}\\; setenv initrd_size \\\${filesize}
setenv loadfdt load mmc \${mmcdev}:\${mmcpart} \${fdtaddr} /dtbs/\${fdtfile}

setenv loadfiles run loadkernel\\; run loadinitrd\\; run loadfdt
setenv mmcargs setenv bootargs console=\${console} root=\${mmcroot} rootfstype=\${mmcrootfstype} rootflags=\${mmcrootflags}

run loadfiles; run mmcargs; bootz \${loadaddr} \${initrd_addr}:\${initrd_size} \${fdtaddr}
EOF

    # boot.scr for CubieTruck
    mkimage -C none -A arm -T script -d /boot/boot.cmd /boot/boot.scr

    # DTBs for CubieTruck
    mkdir -p /boot/dtbs
    cp /usr/lib/$kernelVersion/* /boot/dtbs

    # extra boot modules
    echo "rtc_sunxi" >> /etc/initramfs-tools/modules
}

case "$MACHINE" in
    beaglebone)
    beaglebone_setup_boot
    beaglebone_flash
    beaglebone_repack_kernel
    enable_serial_console ttyO0
    ;;
    cubieboard2)
    cubieboard2_setup_boot
    enable_serial_console ttyS0
    ;;
esac