Embedded Linux

Learning

• • BuildRoot is a set of makefiles and patches that are intended to simplify the process of building an entire embedded Linux system.

    • A sizeable number of source file tarballs are available

  • Cross Linux From Scratch is the website of a project dedicated to instruction in creating your own customized Linux system from source code

    • Documents on Cross-Compiled Linux from Scratch - Embedded:

    • ARM

    • MIPS

    • x86

  • Embedded Linux Wiki offers a lot of embedded Linux related information

Emulators, etc.

• • QEMU is an emulator that can allow code to run on a host system (e.g. Intel-based Linux desktop) that was written for a different hardware platform (e.g. ARM).  There are a number of useful QEMU related links:

  • QEMU ARM system with DirectFB interface

  • Getting started with an embedded Linux system emulator

  • Tutorial: a simple embedded Linux system

  • System emulation with QEMU

  • Running Linux for ARM under QEMU

  • HowTo: Running Fedora ARM under QEMU

  • Using QEMU to emulate absent hardware

  • Aboriginal Linux is "a set of tools to build custom virtual machines [that let] you boot virtual PowerPC, ARM, MIPS and other exotic systems on your x86 laptop (using an emulator such as QEMU)."

Optimizations, etc.

• • Optimizing boot time for embedded Linux, by Chris Simmonds:

  • Slides

  • Paper

UI packages

• • DirectFB is a "thin library" that provides APIs for displaying text and graphics to frame buffer devices

  • nano-X (formerly Microwindows) provides APIs for performing Windows-style and X11-style operations

Packages

• • atinout is a simple command line utility for sending commands to a modem and reading responses

  • Cairo is a library recommended by someone to use with Pango on DirectFB for a better integrated internationalization rendering solution

  • DirectFB is a graphics library for working with frame buffer devices (a typical implementation on embedded Linux systems)

    • DirectFB tutorials, including online HTML pages

  • API references

    • The official DirectFB wiki includes some great reference material:

    • Configuring DirectFB

  • MAN page for DIRECTFBRC

    • Presentations from the DirectFB site:

    • DirectFB Internals - Things You Need to Know to Write Your DirectFBgfxdriver

  • MAD (MPEG Audio Decoder) is an application with libraries that can play MP3 files

    • Repository of MAD source tarballs on SourceForge

  • Pango is a text rendering library intended for internationalization projects

    • Pango downloads from gnorme.org

  • Pango reference manual

  • Picocom is a small command line utility that works similarly to minicom

  • TSlib is a hardware abstraction layer (HAL) for touchscreen hardware.

    • Wiki page of information, offered by Texas Instruments

    • Download link for source tarball

    • Github repository of source

References

• • Choosing free software graphical libraries for embedded devices, a PDF of the presentation brought to the 2008 Embedded Linux Conference Europe by Thomas Petazzoni with Free Electrons  (eLinux also has an older copy of the PDF document)

  • Embedded Linux system development, a PDF of a training document from Free Electrons.

  • The Texas Instruments Embedded Processors wiki has a number of useful pages:

  • Booting the Linux kernel using u-boot

  • initrd

  • Writing the kernel image to NAND flash

• embedded-linux.co.uk: The Inner Penguin