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LancelOS arm-kernel
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Description:
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The goal is to write a simple ARM kernel for Raspberry (only Pi 2 for now but
it won't be too hard to port) in Zig.
I want to understand how my computer work and I like learning by doing.
This is not and will never be intended for any kind of production environment.

Features:
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[x] Boot
[x] UART Read/Write
[x] Kernel/Userspace memory separation
[x] "device file" model
[x] open, read, write, close syscalls (on char devices only)
[x] brk syscall, malloc/free in userspace
[x] Framebuffer Read/Write
[x] Virtual TTY with a home-made font :)
[ ] Keyboard
[ ] File system
[x] Multiple processes running at the same time, context switching
[ ] Non system-blocking syscalls
[ ] Pipe
[ ] Userspace shell
... Maybe more, don't know yet

Usage:
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You need to have the bare-metal ARM cross-assembly/link tools install
On Archlinux it's extra/arm-none-eabi-binutils

As well as the zig compiler and qemu if you want to test it on your machine.

You can build the kernel with:
	make

This will build the kernel to an ./init.bin file

To launch it in qemu:
	make qemu-screen

License:
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This project is licensed under the "THE GAME LICENSE"

Resources:
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https://wiki.osdev.org

https://developer.arm.com/documentation/ddi0595/2021-12/AArch32-Registers

@AsahiLina's explanation of CVE-2022-32947 is a very entertaining way to
understand page tables https://www.youtube.com/watch?v=hDek2cp0dmI

BROADCOM BCM2837 ARM Peripherals datasheet

https://linux-kernel-labs.github.io/refs/heads/master/index.html

https://www.kernel.org/doc/html/latest/index.html