/sos

Simple Operating System for educational purposes

Primary LanguageCGNU General Public License v2.0GPL-2.0

Sos

Build Status

Simple Operating System for educational purposes

This is a playground which hosts code for a simple operating system. In this project I aim to learn how operating systems work by building one for myself.

Originally, the work was started in BeagleBoard rev.c3, which has TI OMAP3550 processor. However, due to the difficulties in compiling/linking/flashing/running/debugging cycle in BeagleBoard, the development mostly occurs in emulated RealviewPB platform.

Building

The code is structed into project, target, platform, and arch. You can build the kernel by invoking make <project> where project is one of the projects in project/ directory. For example, to build for realview-pb platform, use make realview-pb-test

Using local.mk

If you are building for the same platform again and again, you can define the project in local.mk file by putting;

PROJECT := realview-pb-test

The build system reads local.mk and runs accordingly. After putting the project information, make can be invoked alone.

Turning compilation output

You can turn the compiler output by putting the following in your local.mk;

NOECHO :=

Supported Versions

Currently, ARMv7 is supported. I do not have a legacy concern for now so make sure that you have ARMv7 chip. As this project is for educational purposes, legacy support for older chips is not a main concern. LK has support for older chips but I removed the legacy part for clean and consistent code. If you are curious about adding a support for your board or chip, please feel free to send patches.

Apart from the CPU architecture, supported boards are:

  • BeagleBoard rev.c3
  • Realview-PB

Acknowledgement

The build system was written by Travis Geiselbrecht (geist). It is also used in Little Kernel. Sos is highly inspired by lk for both project structure and startup code. Thanks for geist, and #osdev for all their help.