Bao Hypervisor Demo Guide

This tutorial provides a step-by-step guide on how to run different demo configurations of the Bao hypervisor featuring multiple guest operating systems and targeting several supported platforms. The available demos are:

NOTE

This tutorial assumes you are running a standard Linux distro (e.g. Debian) and using bash.

If you have any doubts, questions, feedback, or suggestions regarding this guide, please raise an issue in GitHub or contact us via info@bao-project.org.

If you run into any problem while following this guide, we ask you to raise an issue on Github, but first please make sure you are using the same or newer/compatible versions of the tools and software listed in Appendix III (not all are needed for all target platforms).

-1. Install dependencies

sudo apt install build-essential bison flex git libssl-dev ninja-build \
    u-boot-tools pandoc libslirp-dev pkg-config libglib2.0-dev libpixman-1-dev \
    gettext-base curl xterm cmake python3-pip xilinx-bootgen

pip3 install pykwalify packaging pyelftools

0. Download and setup the toolchain

Download the latest bare-metal cross-compile toolchain for your target architecture:

a) For Armv8 Aarch64, use the aarch64-none-elf- toolchain.

Download it from the Arm Developer’s website.

b) For Armv7 or Armv8 Aarch32, use the arm-none-eabi- toolchain.

Download it from the Arm Developer’s website.

c) For RISC-V, use the riscv64-unknown-elf- toolchain.

Download it from SiFive’s Freedom Tools github reposiroty.

Install the toolchain. Then, set the CROSS_COMPILE environment variable with the reference toolchain prefix path:

export CROSS_COMPILE=/path/to/toolchain/install/dir/bin/your-toolchain-prefix-

1. Setup base environment

Clone this repo and cd to it:

git clone https://github.com/bao-project/bao-demos
cd bao-demos

Depending on your target platform and demo, setup the PLATFORM and DEMO environment variables using the IDs in Appendix I. For example, for a system configuration targeting the ZCU102 board and featuring a dual-guest Linux+FreeRTOS demo:

export PLATFORM=zcu102
export DEMO=linux+freertos

Note that not every platform supports every demo. The supported platform/demo combinations are available in Appendix II.

At this point you have two options:

A) Use automated make

Just execute:

make -j$(nproc)

And all the needed source and images will be automatically downloaded and built. The makefiles will also print some instructions for you to carry out when it is not possible to automate a given step for some reason (e.g. download behind authentication wall). It will also print the instructions on how to deploy the images on your target platform. To quiet instructions pass NO_INSTRUCTIONS=1 to make.

WARNING

The makefiles will automatically accept end-user license agreements (EULAs) on your behalf for some of the downloaded firmware. If you wish to be prompted to accept them manually, pass ALWAYS_ASK=1 to make.

If you are targetting an emulator platform like QEMU, after building you can start it with:

make run

In this case, if you don’t have qemu for the target architecture installed, it will build it for you.

NOTE

These makefiles are intended ONLY to automate this guide’s steps; not to be used as any kind of build system during development.

B) Follow the step-by-step guide

As an alternative, we provide a step-by-step guide that you can follow to build all the necessary software and deploy it to your target platform.

B.1) Setup ARCH manually

Setup the ARCH environment variable manually according to Appendix I. For example, for the ZCU102 platform:

export ARCH=aarch64

B.2) Create working directory

Create the working directories where you’ll place the source code and final images:

export BAO_DEMOS=$(realpath .)
export BAO_DEMOS_WRKDIR=$BAO_DEMOS/wrkdir
export BAO_DEMOS_WRKDIR_SRC=$BAO_DEMOS_WRKDIR/srcs
export BAO_DEMOS_WRKDIR_BIN=$BAO_DEMOS_WRKDIR/bin
export BAO_DEMOS_WRKDIR_PLAT=$BAO_DEMOS_WRKDIR/imgs/$PLATFORM
export BAO_DEMOS_WRKDIR_IMGS=$BAO_DEMOS_WRKDIR_PLAT/$DEMO
mkdir -p $BAO_DEMOS_WRKDIR
mkdir -p $BAO_DEMOS_WRKDIR_SRC
mkdir -p $BAO_DEMOS_WRKDIR_BIN
mkdir -p $BAO_DEMOS_WRKDIR_IMGS

B.3) Build guests

Build guests according to the target demo:

B.4) Build Bao

Clone Bao’s repo to the the working directory:

export BAO_DEMOS_BAO=$BAO_DEMOS_WRKDIR_SRC/bao
git clone https://github.com/bao-project/bao-hypervisor $BAO_DEMOS_BAO\
    --branch demo

Copy your config to the working directory:

mkdir -p $BAO_DEMOS_WRKDIR_IMGS/config
cp -L $BAO_DEMOS/demos/$DEMO/configs/$PLATFORM.c\
    $BAO_DEMOS_WRKDIR_IMGS/config/$DEMO.c

Build it:

make -C $BAO_DEMOS_BAO\
    PLATFORM=$PLATFORM\
    CONFIG_REPO=$BAO_DEMOS_WRKDIR_IMGS/config\
    CONFIG=$DEMO\
    CPPFLAGS=-DBAO_DEMOS_WRKDIR_IMGS=$BAO_DEMOS_WRKDIR_IMGS

And copy the resulting binary into the final image directory:

cp $BAO_DEMOS_BAO/bin/$PLATFORM/$DEMO/bao.bin\
    $BAO_DEMOS_WRKDIR_IMGS

B.5) Build Firmware and Deploy

Build the firmware and deploy the system according to the target platform:

AArch64 platforms:

AArch32 platforms:

RISC-V platforms:

QEMU virt

Appendix I

	PLATFORM	ARCH
Xilinx ZCU102	zcu102	aarch64
Xilinx ZCU104	zcu104	aarch64
NXP i.MX8QM	imx8qm	aarch64
Nvidia TX2	tx2	aarch64
Raspberry 4 Model B	rpi4	aarch64
QEMU Aarch64 virt	qemu-aarch64-virt	aarch64
FVP-A AArch64	fvp-a	aarch64
FVP-R AArch64	fvp-r	aarch64
FVP-A AArch32	fvp-a-aarch32	aarch32
FVP-R AArch32	fvp-r-aarch32	aarch32
QEMU RV64 virt	qemu-riscv64-virt	riscv64

	DEMO
Baremetal guest	baremetal
Linux+FreeRTOS	linux+freertos
Linux+Zephyr	linux+zephyr
Zephyr+Baremetal	zephyr+baremetal

Appendix II

	baremetal	linux+freertos	linux+zephyr	zephyr+baremetal
zcu102	x	x
zcu104	x	x
imx8qm	x	x
tx2	x	x
rpi4	x	x	x
qemu-aarch64-virt	x	x	x
fvp-a-aarch64	x	x	x	x
fvp-a-aarch32	x	x	x	x
fvp-r-aarch64	x	x	x	x
fvp-r-aarch32	x			x
qemu-riscv64-virt	x	x

Appendix III

Tool	Version
arm-none-eabi-gcc	11.3.1
aarch64-none-elf-gcc	11.2.1
riscv64-unknown-elf-gcc	10.2.0
make	4.2.1
dtc	1.5.0
gcc	9.3.0
mkimage	20.10
cmake	3.20.0
ninja	1.10.1