RVVM - The RISC-V Virtual Machine

RISC-V CPU & System software implementation written in С

What's working

• Passes RISC-V compliance/torture tests for both RV64 & RV32
• OpenSBI, U-Boot, custom firmwares boot and execute properly
• Working Linux, FreeBSD, OpenBSD, Haiku OS & other cool OSes
• Tracing JIT, multicore support
• Framebuffer display, mouse & keyboard, UART shell
• NVMe storage drives
• Networking

💡 Tell me more...

• Feature-complete RV64IMAFDC instruction set
• Multicore support (SMP), SV32/SV39/SV48/SV57 MMU
• Tracing RVJIT with x86_64, ARM64, RISC-V, i386, ARM backends (faster than QEMU, yay!)
• Bootrom, Kernel Image loading, ELF support
• Device Tree auto-generation, passing to firmware/kernel
• RVVM Public API for VM integration
• UART 16550a-compatible text console
• PLIC/ACLINT, Timers, Poweroff/reset
• Generic PCI Express Bus
• NVMe storage, image TRIM support, fast IO
• Framebuffer display, GUI for X11/WinAPI/Haiku/SDL
• I2C HID keyboard & mouse, OpenCores I2C controller
• Realtek RTL8169, OpenCores Ethernet NICs
• Userspace networking
• Deprecated: PS2 keyboard & mouse, ATA (IDE) drive, Linux TAP

📦 Installing

🛠 Building

Currently builds using GNU Make (recommended) or CMake and is extremely portable.

git clone https://github.com/LekKit/RVVM
cd RVVM
make
cd release.linux.x86_64
./rvvm_x86_64 -h

You can configure the build with USE flags. To cross-compile, pass CC=target-gcc to make. If it fails to detect features, pass ARCH/OS variables explicitly.

Examples:

make lib CC=aarch64-linux-android21-clang USE_FB=0
make lib all CC=x86_64-w64-mingw32-gcc USE_NET=1
make CFLAGS=-m32 ARCH=i386 USE_RV64=0 BUILDDIR=build BINARY=rvvm
make CC=mipseb-linux-gnu-gcc USE_JIT=0

Alternatively, you can use CMake:

git clone https://github.com/LekKit/RVVM
cd RVVM
mkdir build
cmake -S. -Bbuild
cmake --build build --target all
cd build
./rvvm -h

🚀 Running

./rvvm fw_jump.bin -k u-boot.bin -i drive.img -m 2G -smp 2 -res 1280x720

Argument explanation:

[fw_jump.bin]          Initial M-mode firmware, OpenSBI in this case
-k, -kernel u-boot.bin S-mode kernel payload (Linux Image, U-Boot, etc)
-i, -image drive.img   Attach storage image (Raw format, NVMe as of now)
-m, -mem 2G            Memory amount (may be suffixed by k/M/G), default 256M
-s, -smp 2             Amount of cores, single-core machine by default
-res 1280x720          Changes framebuffer & VM window resolution
-rv32                  Enable 32-bit RISC-V, 64-bit by default
 . . .
-serial /tmp/pts1      Add more serial ports (use stdout to bring UART over terminal as usual)
-nvme drive.img        Explicitly attach storage image as NVMe device
-ata drive.img         Explicitly attach storage image as ATA (IDE) device
-cmdline, -append ...  Override/append default kernel command line
-jitcache 64M          Raise JIT cache limit (64M recommended for complex guests)
-nogui, -nojit         Disable GUI (Use only UART), Disable JIT (for debugging)

Invoke "./rvvm -h" to see extended help.

Tested environments (Likely works elsewhere as well)

OS	JIT	GUI
Linux	Works	X11, SDL
Windows	Works	Win32, SDL
MacOS X	Works, need signing for M1	SDL, XQuartz
FreeBSD	Works	X11, SDL
Haiku OS	Works	Haiku, SDL
Serenity	Works	SDL
Windows CE	Broken (?)	Win32
Emscripten	-	SDL

⚖️ License

This work is dual-licensed under GPL 3.0 and MPL 2.0. You can choose between one of them if you use this work.

If you wish to use this work as a component of a larger, non-GPL compliant project, you are free to do so in any form (Static linkage, binary distribution, modules) as long as you comply with the MPL 2.0 license.

For any form of software distribution, changes made precisely to this work should be made public to comply with either licenses.

Source file headers should be gradually transitioned to reflect their reusability.

🎉 Contributions

	Achievements	Working on
LekKit	RVVM API & infrastructure RV64IMAFDC interpreter, MMU/IRQs/Priv/etc RVJIT Compiler, X86/RISC-V backends NVMe, RTL8169, Framebuffer, many tiny devices Userspace network Rework of PCIe, PLIC, etc	Networking, Userspace emulation COW blk-dedup image format
cerg2010cerg2010	Important fixes, RV64 groundwork, FPU Initial PLIC & PCI, PS2 HID, ATA, OC Ethernet ARM/ARM64 RVJIT backends	Testing, Assistance
Mr0maks	Initial C/M/Zicsr extensions, initial UART, VM debugger ARM32 mul/div JIT intrinsics	-
0xCatPKG	Userspace network & API improvements Extended testing & portability fixes	HD Audio
X547	Haiku GUI, I2C HID, Userland API assistance	Guest Haiku support, UserlandVM
iyzsong	OpenBSD & PLIC fixes, Chardev API
nebulka1	Relative input mode

🔍 TODO

• Sparse block image format with compression/deduplication
• Suspend/resume to file, VM migration
• Linux userspace binary emulation (WIP)
• Sound (HD Audio or else)
• VFIO for GPU passthrough
• More RVJIT optimizations, shared caches
• FPU JIT (Complicated AF to make a conformant one)
• Vector/Bitmanip extensions
• Other peripherals from real boards (SiFive GPIO, flash)
• Maybe virtio devices (For better QEMU interoperability, current devices are plenty fast)
• Free page reporting via virtio-balloon
• A lot more...
• KVM hypervisor? Alternative CPU engines?

The RISC-V trade name is a registered trade mark of RISC-V International.