Embedded Building Tools BOF

Embedded Linux Conference April 2009

Embedded building tools BOF

Thomas Petazzoni Michael Opdenacker Free Electrons http://freeelectrons.com/

1 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Rights to copy

© Copyright 20082009, Free Electrons feedback@freeelectrons.com Document sources available on: http://freeelectrons.com/pub/conferences/2009/elc/ Corrections, suggestions, contributions and translations are welcome! Attribution – ShareAlike 3.0 Latest update: Apr 29, 2009 You are free to copy, distribute, display, and perform the work to make derivative works to make commercial use of the work Under the following conditions Attribution. You must give the original author credit. Share Alike. If you alter, transform, or build upon this work, you may distribute the resulting work only under a license identical to this one. For any reuse or distribution, you must make clear to others the license terms of this work. Any of these conditions can be waived if you get permission from the copyright holder. Your fair use and other rights are in no way affected by the above. License text: http://creativecommons.org/licenses/bysa/3.0/legalcode 2 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Which tools to build your system?

OpenEmbedded Vendor tools (Eclipse) Buildroot Gentoo embedded Scratchbox Crosstool (toolchain only) PTXdist Crosstoolng (toolchain only) LTIB ELDK Home made tools Others? Firmware Linux

3 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Buildroot

Pros Supports uClibc Simple design (kernel config interface, set of Makefiles) Efficient Reproducibility of the build process Cons Doesn't support glibc, except with external toolchain and a bit of tuning Takes care of building the toolchain (2 in 1) No clean way of separating productspecific changes No packages

4 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Scratchbox

Pros Transparent crosscompilation Transparent execution Supports both uClibc and glibc Cons No infrastructure for build reproducibility Complex to add new host tools (need to compile them) Only uses its own toolchains (can compile your own, but complicated to integrate in Scratchbox) No recipes, no tool patches shared with the community.

5 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com OpenEmbedded Pros Clean separation of the build tool and the recipes Ability to generate a root filesystem and packages Clean separation of productspecific changes Widely used in the community Can generate packages Cons No stable releases Steep learning curve Very slow to run (for what reason ?) Too generic. Huge boot times Packages mandatory 6 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Firmware Linux

By Rob Landley Not using crosscompiling, but only native compiling thanks to Qemu Similar approach than Scratchbox, but less tricks. How mature is it ?

7 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Home made tools

Pros Meets your product needs Cons No free updates to mainstream software changes High maintenance cost. Sometimes difficult to extend. Only one person understands its design. Lot of legacy cruft in it. Don't always meet future product needs.

8 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com LTIB

Pros Clean separation of build system and packages Supports both uClibc and glibc Easy to extend to support new boards Accepts standard toolchains Cons Only used on Freescale boards? Size of community?

9 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com The other ones ?

PTXdist Very similar to Buildroot Relies on a separate tool for building the toolchain, but seems limited to glibc Emdebian Vendor tools Great features But difficult to evaluate without a subscription.

10 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Tools compared

License Small glibc (G) Reproducibility Popularity Actively systems uClibc (U) / Leverage maintaine d

Buildroot Free Yes G Good Good Yes

Scratchbox Free Yes G + U Poor Low Yes

OpenEmbedded Free No G + U Good Very good Definitely

LTIB Free Yes G + U Good Low Yes

PTXdist Free Yes G Good Low Yes

Gentoo embedded Free No? G (U?) ? Low? Yes

Firmware Linux Free Yes ? Poor Low Rob never sleeps

Vendor tools Closed ? G + U Good N/A Yes

Home made Closed ? ? ? N/A ?

11 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Building the toolchain

Buildroot Mixed with root filesystem construction, not really nice Only uClibc supported Crosstool Not really nice configuration through shell scripts Only glibc supported Crosstoolng Much better configuration interface Supports both uClibc and glibc Hasn't attracted a lot of community attention (yet ?)

12 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Tool survey

Number of users per tool in the BOF

15 OLS 2008 ELC 2009

0 Scratchbox PTXdist Firmware Linux Vendor tools ELDK Openwrt Buildroot OpenEmbedded LTIB Gentoo embedded Home made uClinuxdist Desktop distro

13 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com Questions

Why is the community so fragmented ? Because it is not possible to create a universal tool that would match the needs of everybody ? Is it a problem ? NIH syndrom ? What are the missing features ? What are your complaints about the existing tools ? Complexity ? Lack of flexibility ? Don't see the need ?

14 Free Electrons. Kernel, drivers and embedded Linux development, consulting, training and support. http//freeelectrons.com