Rust PCI Echo Device for QEMU

Overview

This project is a Rust implementation of the PCI Echo Device originally developed in C by Johannes4Linux.
The goal is to replicate the device’s functionality using Rust, leveraging its safety and modern features, while integrating with QEMU as a PCI device.

Prerequisites

• QEMU source code (matching or compatible version)
• Build tools: clang, gcc, make, pkg-config, etc.
• MSYS2 environment on Windows (also known as mynwin) for building QEMU and dependencies
• Rust toolchain (install via rustup)
• Add bindgen and clang to mingw: pacman -S mingw-w64-ucrt-x86_64-rust-bindgen mingw-w64-ucrt-x86_64-clang

Integration Steps

1. Clone QEMU source

git clone https://git.qemu.org/git/qemu.git
cd qemu

2. Prepare build environment

On Windows, you can use MSYS2 (minwin) as your build environment. For setup and compilation instructions, you may follow guides such as:
Compiling QEMU for Windows - Itayemi's Blog

3. Create wrap file for Rust subproject

Inside the subprojects directory of the QEMU source tree, create a file named pci-echodev-1-rs.wrap with the following content:

[wrap-file]
directory = pci-echodev-1-rs

# method = cargo
# patch_directory = pci-echodev-1-rs
[provide]
dependency_names = pci-echodev-1-rs

This file instructs QEMU’s build system how to include the Rust subproject as a wrapped dependency.

4. Add Rust PCI Echo Device subproject

Place the Rust implementation under pci-echodev-rs/ inside the QEMU subprojects directory and rename it to pci-echodev-1-rs.

5. Add to meson qemu files

pci_echodev_1_rs_dep = dependency('pci-echodev-1-rs', native: true)

system_ss.add(pci_echodev_1_rs_dep)

6. Build qemu

Navigate to the qemu directory and build:

./configure --enable-sdl --enable-gtk --enable-slirp # or enabled whatever you need
make

7. Run QEMU with Rust PCI Echo Device

Example command to start QEMU with the device enabled:

./qemu-system-aarch64 -device pci-echodev

Usage

Describe how to test the echo functionality, e.g., writing and reading MMIO regions to verify data echo.

Development

Regenerate qemu bindings

./gen-bindings.sh

License

Licensed under the MIT License.

References

• Original pci-echodev project
• QEMU PCI Device Development
• Rust FFI and Integration
• Compiling QEMU for Windows

---

Feel free to expand this README with build instructions, known issues, or contribution guidelines as your project evolves.

INSTALAR alguno de estos para tener bindgen

pacman -S  mingw64/mingw-w64-x86_64-clang
pacman -S  mingw-w64-x86_64-clang mingw-w64-ucrt-x86_64-rust-bindgen
pacman -S  mingw64/mingw-w64-x86_64-clang
pacman -S  mingw-w64-x86_64-clang mingw-w64-ucrt-x86_64-rust-bindgen
pacman -S mingw-w64-ucrt-x86_64-rust-bindgen mingw-w64-ucrt-x86_64-clang

Esto es para usar el rust de windows dentro de ucrt64 export PATH="/c/Users/lfern/.cargo/bin:$PATH"

Para que compile sin que los warnings sean considerados como errores. Hacerlo antes del configure export RUSTFLAGS="-Awarnings"

---

Chequeando paquete: mingw-w64-ucrt-x86_64-rust-bindgen ✓ Instalado Chequeando paquete: mingw-w64-ucrt-x86_64-clang ✓ Instalado