build: `cargo build --target arm-none-eabihf.json -Z build-std=core,compiler_builtins`

qemu: `qemu-system-arm -m 256 -M raspi0 -serial stdio -kernel kernel.elf`

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# References

- https://os.phil-opp.com/minimal-rust-kernel/
- https://wiki.osdev.org/Raspberry_Pi_Bare_Bones
- https://wiki.osdev.org/Raspberry_Pi_Bare_Bones_Rust