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Andre Richter b30bc518c4 Switch to GCC objdump and nm The GCC versions of `objdump` and `nm` seem to have better out-of-the-box support (for AArch64). Demangling works better, and instructions in objdump are presented as 4 bytes instead of 4 * 1 bytes, which helps a lot. Hence, switch to the GCC versions for now until LLVM has caught up.		4 years ago
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.vscode	Run of prettier over whole repo	4 years ago
src	Switch to new Rust inline asm! syntax	4 years ago
Cargo.lock	Add code for tutorial 01	5 years ago
Cargo.toml	Make cortex-a platform specific dep	4 years ago
Makefile	Switch to GCC objdump and nm	4 years ago
README.CN.md	Remove xbuild. Use upstream aarch64 rust-std 🎉 🦀	4 years ago
README.md	Streamline READMEs	4 years ago
build.rs	Let cargo track changed files	4 years ago

Tutorial 01 - Wait Forever

tl;dr

The project skeleton is set up.
A small piece of assembly code runs that just halts all CPU cores executing the kernel code.

Custom link.ld linker script.
- Load address at 0x8_0000
- Only .text section.
main.rs: Important inner attributes:
- #![no_std], #![no_main]
cpu.S: Assembly _start() function that executes wfe (Wait For Event), halting all cores that are executing _start().
We (have to) define a #[panic_handler] function.
- Just waits infinitely for a cpu event.

In the project folder, invoke QEMU and observe the CPU core spinning on wfe:

$ make qemu
[...]
IN:
0x00080000:  d503205f  wfe
0x00080004:  17ffffff  b        #0x80000