hikami

A lightweight Type-1 hypervisor for RISC-V H-extension, featuring RISC-V extension emulation.

This project aims not only to realize a lightweight hypervisor that can be used on RISC-V H extensions, but also to easily reproduce and manage the "extension" on the hypervisor.
Poster in RISC-V Days Tokyo 2024 Summer: PDF
Paper in ComSys2024(ja): link

Related projects

• ozora: Generator for hypervisor(hikami) module and decoder (raki).
• raki: RISC-V instruction decoder.
• wild-screen-alloc: Slab allocator for bare-metal Rust.

Documents

$ cargo doc --open

Getting Started

Setup

$ git clone https://github.com/buildroot/buildroot.git
$ cd buildroot/
$ make qemu_riscv64_virt_defconfig
$ make -j$(nproc)
$ ln -s output/images/rootfs.ext2 path/to/hikami/rootfs.ext2
$ ln -s output/build/linux-x.x.x/vmlinux path/to/hikami/guest_image/vmlinux
# optional
$ ln -s path/to/initrd path/to/hikami/guest_image/initrd

# copy host dts and edit to change user memory config
# QEMU's dtb can be obtained by adding the option `-machine dumpdtb=qemu.dtb`.
$ vim guest_image/guest.dts

Run on QEMU

# The actual command to be executed is written in .cargo/config.toml.
$ cargo r

Run on FPGA

The target FPGAs are as the following. (boards supported by vivado-riscv repository)

- AMD VC707 
- AMD KC705 
- Digilent Genesys 2 
- Digilent Nexys Video 
- Digilent Nexys A7 100T 
- Digilent Arty A7 100T

Building the FPGA environment

# set environment
$ git clone https://github.com/Alignof/vivado-risc-v -b feature/hikami
$ cd vivado-risc-v
$ make update-submodules

# Build FPGA bitstream
# Connect a micro-B cable to `PROG`
$ source /opt/Xilinx/Vivado/2024.2/settings64.sh
$ make CONFIG=rocket64b1 BOARD=nexys-video bitstream

# Prepare the SD card
$ ./mk-sd-card

# Program the FPGA flash memory
$ Xilinx/Vivado/2023.2/bin/hw_server
$ env HW_SERVER_URL=tcp:localhost:3121 xsdb -quiet board/jtag-freq.tcl
$ make CONFIG=rocket64b2 BOARD=nexys-video flash

See also for an environment information: https://github.com/Alignof/vivado-risc-v/blob/master/README.md

Boot

# Connect a micro-B cable to `UART`
$ sudo picocom -b 115200 /dev/ttyUSB2 # <- select the corresponding serial port 

# login: debian
# password: debian

Run on Milk-V Megrez

Coming soon...

References

• The RISC-V Instruction Set Manual: Volume I Version 20240411
• The RISC-V Instruction Set Manual: Volume II Version 20240411
• Rvirt
• hypocaust-2

Acknowledgement

Exploratory IT Human Resources Project (MITOU Program) of Information-technology Promotion Agency, Japan (IPA) in the fiscal year 2024.
https://www.ipa.go.jp/jinzai/mitou/it/2024/gaiyou-tn-3.html