Xen Development Environment on RaspberryPi

🙏🏻 Welcome to XDE - Xen Development Environment built using yocto, which enables you to develop virtualized guest domains on top of Linux as Dom0 (domain 0) on Raspberry Pi 4. To get started, please read "Getting Started" section below. 🙏🏻

Getting Started

Setup yocto

• git clone https://github.com/aananthcn/meta-virt-rpi.git
• ./meta-virt-rpi/setup-yocto.sh
  After the above 2 steps, if you do ls from your current directory, you should see the following:
  meta-openembedded meta-raspberrypi meta-virt-rpi meta-virtualization poky

Build the target image

• source poky/oe-init-build-env
• bitbake dom0-image
  • This will take some time (~8 hrs for first time on 10th Gen Intel i5 machine with 16GB RAM)

Flash the image

• From build folder, navigate to tmp[-glibc]/deploy/images/raspberrypi4-64
• Check for image with name dom0-image-raspberrypi4-64-sdcard.img
• Follow either of these steps to flash the above image into the sd card
  • Linux: https://www.raspberrypi.org/documentation/installation/installing-images/linux.md
  • Windows: https://www.balena.io/etcher/

Boot the device

• Setup the serial cable connection and terminal emulator as in https://elinux.org/RPi_Serial_Connection
• Insert the SD Card and power on.
• You should get u-boot prompt in serial console with in first 2 seconds, press any key if you want to stop at that stage and explore / do something with u-boot.
• Then you will see Xen will get booted and finally you should see Linux boot messages in serial console.
• Enter root as username, you will now login to domain 0 (Linux OS) there.
• To switch to Xen console, type 'CTRL-a' three times and you will get Xen console.
  • Type 'h' to see different Xen commands.
  • Type 'e' to see all event channel information.
  • Type 't' to see all timer queues.
• Type 'CTRL-a' three times to go back to domain 0 (Linux).
  • Type htop to know the resources allocated to domain 0 (Linux)
  • Type xl list to list all domains running on the system.
  • Type xl info to know detailed information about xen hypervisor.
• Happy hacking!

PC Setup Information

• Ethernet IP (IPv4)
  • Set your host ethernet as manual and set the host-ip as 192.168.137.100
  • The target in both bootloader and in domain-0 is set as 192.168.137.101
• User ID & Password
  • username: root
  • No password in serial console.
  • Setup password via serial console for SSH login and copy of files.

Design Notes

meta-virt-rpi

To store recipes, scripts and patches for Raspberry Pi

local.conf contents

MACHINE ?= "raspberrypi4-64" \ PREFERRED_PROVIDER_virtual/bootloader = "u-boot" \ PREFERRED_PROVIDER_virtual/kernel = "linux-xen" \ CORE_IMAGE_EXTRA_INSTALL += " u-boot" \ PREFERRED_VERSION_u-boot = "2020.07" \ // PREFERRED_VERSION_xen = "4.13.0" \ DISTRO_FEATURES += " virtualization xen" \ DL_DIR = "/opt/dl-dir"

bblayer.conf contents

POKY_BBLAYERS_CONF_VERSION = "2"

BBPATH = "${TOPDIR}" BBFILES ?= ""

BBLAYERS ?= " \ /home/aananth/projects/xen-rpi4yocto/poky/meta \ /home/aananth/projects/xen-rpi4yocto/poky/meta-poky \ /home/aananth/projects/xen-rpi4yocto/poky/meta-yocto-bsp \ /home/aananth/projects/xen-rpi4yocto/meta-openembedded/meta-oe \ /home/aananth/projects/xen-rpi4yocto/meta-openembedded/meta-filesystems \ /home/aananth/projects/xen-rpi4yocto/meta-openembedded/meta-python \ /home/aananth/projects/xen-rpi4yocto/meta-openembedded/meta-networking \ /home/aananth/projects/xen-rpi4yocto/meta-virtualization \ /home/aananth/projects/xen-rpi4yocto/meta-raspberrypi \ /home/aananth/projects/xen-rpi4yocto/meta-virt-rpi \ "

u-boot Environment to boot Xen

setenv bootargs 'console=hvc0 clk_ignore_unused root=/dev/mmcblk0p2 rootwait' \ setenv do_dtbsetup 'fatload mmc 0:1 ${fdt_addr} bcm2711-rpi-4-b.dtb && fdt addr ${fdt_addr} && fdt resize && fatload mmc 0:1 0x18000 overlays/pi4-64-xen.dtbo && fdt apply 0x18000' \ setenv load_xen 'fatload mmc 0:1 0x200000 xen-raspberrypi4-64' \ setenv load_dom0 'fatload mmc 0:1 0x480000 Image' \ setenv xen_bootcmd 'booti 0x200000 - ${fdt_addr}' \ setenv boot_xen 'run do_dtbsetup; run load_xen; run load_dom0; run xen_bootcmd'