Mimiker: MIPS Micro-Kernel

An experiment with implementation of very simple operating system for Malta board.

Toolchain

To build Mimiker you will need a custom MIPS toolchain we use. You can download a binary debian package from here. It installs into /opt, so you'll need to add /opt/mipsel-mimiker-elf/bin to your PATH.

Otherwise, if you prefer to build the toolchain on your own, download crosstool-ng which we use for configuring the toolchain. You can get it from here. Then:

cd toolchain/mips/
ct-ng build

By default, this will build and install the mipsel-mimiker-elf toolchnain to ~/local. Update your $PATH so that it provides mipsel-mimiker-elf-*, i.e. unless you've changed the install location you will need to append ~/local/mipsel-mimiker-elf/bin to your PATH.

Building

With toolchain in place, you are ready to compile Mimiker. Run

make

in project root. This will result with a mimiker.elf file containing the kernel image.

Running

As you presumably do not own a MIPS Malta board, you will need a simulator to test the kernel. We currently support OVPsim (incl. Imperas proprietary variant) and QEMU. If you're using OVPsim, make sure your $IMPERAS_HOME is set correctly.

We provide a python script which simplifies loading the kernel image to simulator. In project root dir, run:

./launch

This will start the kernel using OVPsim if available, or QEMU otherwise.

Some useful flags to the launch script:

• -h - Prints usage.
• -d - Starts simulation under a debugger.
• -D DEBUGGER - Selects debugger to use.
• -S SIMULATOR - Manually selects the simulator to use.
• -t - Bind simulator UART to current stdio.

Any other argument is passed to the kernel as a kernel command-line argument. Some useful kernel arguments:

• init=PROGRAM - Specifies the userspace program for PID 1. Browse ./user for currently available programs.

If you want to run tests please read this document.

Documentation

Useful sites:

• OSDev wiki
• prpl Foundation

Toolchain documentation:

• Extensions to the C Language Family
• Debugging with GDB
• Linker scripts

MIPS documentation:

• MIPS® Architecture For Programmers Volume II-A: The MIPS32® Instruction Set
• MIPS® Architecture For Programmers Volume III: The MIPS32® and microMIPS32™ Privileged Resource Architecture
• MIPS32® 24KE™ Processor Core Family Software User’s Manual
• MIPS32® 24KEf™ Processor Core Datasheet
• Programming the MIPS32® 24KE™ Core Family
• MIPS® YAMON™ User’s Manual
• MIPS® YAMON™ Reference Manual
• MIPS ABI Project

Hardware documentation:

• MIPS® Malta™-R Development Platform User’s Manual
• Galileo GT–64120 System Controller
• Intel® 82371AB PCI-TO-ISA/IDE XCELERATOR (PIIX4)
• Am79C973: Single-Chip 10/100 Mbps PCI Ethernet Controller with Integrated PHY
• FDC37M81x: PC98/99 Compliant Enhanced Super I/O Controller with Keyboard/Mouse Wake-Up