RustyBoot-RISCV - A bare metal Boot-loader in Rust

#osdev #bootloader #rust #programming

Hey folks!

I’m excited to share my new project: RustyBoot-RISCV, a minimal bare-metal bootloader for RISC-V, written entirely in Rust (no_std, no_main). This is a continuation of my RustyBoot series — but this time for RISC-V!

Why?

I’ve always wanted to explore low-level OS development while keeping the safety and modern tooling of Rust. RISC-V is an open and growing architecture, and writing a bootloader for it seemed like the perfect challenge.

RustyBoot-RISCV aims to be:

Minimal: simple linker script, _start, and UART output.
Modular: UART, memory, filesystem, and ELF modules split for clarity.
Educational: a project for learning + experimenting.
Compatible: runs on QEMU virt machine for easy testing.

Project Structure

├── src/
│   ├── main.rs      # entrypoint (_start)
│   ├── panic.rs     # custom panic handler
│   ├── uart/        # UART driver
│   ├── memory/      # memory handling
│   ├── block/       # block device abstraction
│   ├── fs/          # filesystem support
│   └── elf/         # ELF loader
├── linker.ld        # linker script (entry at 0x8000_0000)
└── boot/            # boot assets (future use)

Build

Make sure you have a RISC-V target installed:

rustup target add riscv64imac-unknown-none-elf

Then Build

cargo build --target riscv64imac-unknown-none-elf

Run in QEMU

qemu-system-riscv64 \
    -machine virt \
    -nographic \
    -bios none \
    -kernel target/riscv64imac-unknown-none-elf/debug/RustyBoot-RISCV \
    -serial mon:stdio