OSu

I am not a professional at OS Development by any means. Don't expect this OS to do anything for a long while

Table Of Contents

• OSu
  • Table Of Contents
  • Disclaimer
  • About
  • Contributors
  • Notable Features
  • Running OSu.img
    • Pre-requisites before building and running the OS
    • Installation of Pre-requisites
  • TODO

Disclaimer

There is no correlation between this OS and the development team behind the game OSU! (Please peppy I just need something to do before OSU! Lazer is complete)

As a restatment from the beginning I am not a professional at OS Development by any means. Don't expect this OS to do anything for a long while

This was started as a hobby project to play around with CPU architecture and learning computers at a fundamental level.

Also I just thought that OSU and OSu would be kinda funny because of the name to be honest

About

There is not much to be offered in the OS in its current stages while I learn more OS development and different protocol implementations

• 64-bit OS with simple barebones kernel
• Emulator: QEMU
• Cross compiler: gcc
• Linker: ld
• UEFI bootloader services

To my knowledge this should work outside of QEMU as in real hardware, I have yet to try it out, (I dont have a PS2 keyboard or mouse so I won't get very far) but later version I will experiment further with real hardware

Contributors

• ZMan2024 (USB-less behavior)

Notable Features

• PS2 Keyboard support
• PS2 Mouse support (kind of)
• Simple frame buffer
• UEFI bootloader
• PCI
• Simple heap
• PIT

Running OSu.img

Pre-requisites before building and running the OS

To run the OS.bin file in the release I would reccomend running the OSu.img file through qemu

Qemu Download Page

• build-essentials (if your're using a debian based system)
• base-devel (if your're using an arch based system)
• mtools (4.0.27)
• qemu
• g++
• nasm

Installation of Pre-requisites

• Debian Installation

  sudo apt update 
  sudo apt install build-essentials qemu g++ nasm make

• Arch Installation

  sudo pacman -S base-devel qemu nasm g++ make 

The mtools installation should work fine on ubuntu 20.04 LTS

mtools --version

if the version is not 4.0.27 you can install it like so

wget -S ftp.gnu.org/gnu/mtools/mtools-4.0.27.tar.gz
tar xf mtools-4.0.27.tar.gz
cd mtools-4.0.27
./configure
sudo make install

If for some reason qemu doesn't work (I've noticed this to be an issue with debian based systems), go to the Qemu Download Page and follow the instruction for installtion there

Assuming QEMU is installed properly and you do have the OSu.img. In the same directory where the .img file is saved, run the command (This might not be 100% accurate because I forget to update this with the build, to ensure you are running the correct qemu command you can open the repository under kernel and look at the last line of the makefile)

qemu-system-x86_64 -machine q35 -device ac97 -drive file=$(BUILDDIR)/$(OSNAME).img -m 256M -cpu qemu64 -drive if=pflash,format=raw,unit=0,file="$(OVMFDIR)/OVMF_CODE-pure-efi.fd",readonly=on -drive if=pflash,format=raw,unit=1,file="$(OVMFDIR)/OVMF_VARS-pure-efi.fd" -net none

To build and Run OSu from in qemu from source run

make

to clean the source run

make clean

TODO

• USB :(
  • 2.0
  • 3.0
• networking capabilities
  • Unknown currently
• Test OS on real hardware
• Sound Drivers
• HPET
• Scheduling :(
  • Threads
  • Context Switching
• File System (beatmaps need to be stored somehow)
• Program Loading
• Debugging
• Local/IO APIC
• Global Constructors (CTORS)
• Stack Smashing Protection