NOTES
=====

This image introduces bootflow changes. We use now OpenSBI -> U-Boot (S-mode)
[extlinux] -> kernel. The kernel and initramfs are wrapped in U-Boot container
for now. This should change later this year once kernel header patches are
merged in kernel and U-Boot.

This image will work with libvirt v.5.3.0 (or above) and QEMU 4.0.0 (or above).
Tested also with libvirt v5.4.0 and v5.5.0.

This image allows updating kernels via dnf + reboot.

This image does not contain out-of-tree patches for SiFive Unleashed board.

This image is also available via virt-builder repository (not signed).
For example:

    % virt-builder \
      --source https://dl.fedoraproject.org/pub/alt/risc-v/repo/virt-builder-images/images/index \
      --no-check-signature \
      --arch riscv64 \
      --size 20G \
      --format qcow2 \
      --hostname fedora1.builders.riscv.rocks \
      fedora-rawhide-developer-20190703n0

See virt-builder man page for more information on how to customize disk images.

The disk image contains two partitions:
- sda1 (/boot) contains kernel, initramfs, extlinux configuration and firmware
  blobs.
- sdta2 contains rootfs.

    % virt-filesystems --long -h --all -a Fedora-Developer-Rawhide-20190703.n.0-sda.raw
    Name       Type        VFS   Label   MBR  Size  Parent
    /dev/sda1  filesystem  ext4  _/boot  -    488M  -
    /dev/sda2  filesystem  ext4  _/      -    7.2G  -
    /dev/sda1  partition   -     -       -    488M  /dev/sda
    /dev/sda2  partition   -     -       -    7.2G  /dev/sda
    /dev/sda   device      -     -       -    8.0G  -

To extract firmware blob install libguestfs-tools-c (Fedora/CentOS/RHEL), then:

    % mkdir a
    % guestmount -a $PWD/Fedora-Developer-Rawhide-*.raw -m /dev/sda1 $PWD/a
    % cp a/opensbi/unstable/fw_payload-uboot-qemu-virt-smode.elf .
    % guestunmount a

Use `fw_payload-uboot-qemu-virt-smode.elf` instead of the kernel.

libvirt (virt-instal):

    [..]
    --boot kernel=$PWD/fw_payload-uboot-qemu-virt-smode.elf \
    [..]

QEMU:

    [..]
    -kernel $PWD/fw_payload-uboot-qemu-virt-smode.elf \
    [..]

You do not need to specify bootargs, initramfs or actual kernel images. U-Boot
will read /boot/extlinux/extlinux.conf (from sda1) to load that information.

Record from extlinux.conf:

    [..]
    label Fedora-Developer-Rawhide-20190703.n.0 (5.2.0-0.rc7.git0.1.0.riscv64.fc31.riscv64)
    	kernel /uImage-5.2.0-0.rc7.git0.1.0.riscv64.fc31.riscv64
    	append ro root=UUID=3b75927f-d59f-4b04-96ce-823ead0046bc rhgb quiet LANG=en_US.UTF-8
    	initrd /uInitrd-5.2.0-0.rc7.git0.1.0.riscv64.fc31.riscv64
    [..]