raspvisor

A simple type-1 hypervisor on Raspberry Pi 3 (aarch64)

Article about raspvisor is here (Japanese).

Warning: This is a hobby project and not for practical use.

Setup

First, write a Raspberry Pi OS (previously called Raspbian) image to your SD card to make partitions and install firmwares. Execute following commands to build. (GNU toolchain for aarch64-linux-gnu is required.)

$ export SD_BOOT_DIR=/path/to/bootpartiton/on/sdcard
$ export SD_ROOTFS_DIR=/path/to/rootfspartiton/on/sdcard
$ make install

Programs runs on a hypervisor startup are hard-coded in src/main.c. I confirmed that programs in example directory can be run on this hypervisor. In example directory, following programs are found.

• test_binary : issues hypervisor call once.
• echo : Mini-UART echo back (based on raspberry-pi-os/lesson02)
• mini-os : a simple operating system which has a process scheduler, interrupt handling and virtual memory support (based on raspberry-pi-os/lesson06)

Enter each directory and make to build. Then copy *.bin file to SD_BOOT_DIR.

Usage

UART is assigned to the hypervisor's console. Connect your cable to the GPIO 14/15 pins.

• ? + l : show the list of VMs
• ? + 1-9 : switch to the console of VM 1-9

Features

• Enabling stage 2 translation
• Memory-mapped IO emulation
  • BCM2837 Interrupt Controller
  • BCM2837 System Timer (inacculate)
  • BCM2837 Mini-UART
• IRQ virtualization by using virtual IRQs
• Trapping access of some system register
• Trapping WFI/WFE instruction

Links

• Armv8-A Virtualization - Learn the Architecture (https://developer.arm.com/architectures/learn-the-architecture/armv8-a-virtualization)
• ARM Architecture Reference Manual ARMv8, for ARMv8-A architecture profile
• 「ハイパーバイザの作り方」(http://syuu1228.github.io/howto_implement_hypervisor/)

License

This software is licensed under the MIT license.

• Source codes and examples (echo and mini-os) are mostly based on Sergey Matyukevich's raspberry-pi-os.
• SD card driver (src/sd.c, src/delays.c, include/sd.h and include/delays.h) is from bzt's raspi3-tutorial.