The ARM Embedded Linux File System

Note that in all ARM EMbedded file systems many important security features were dropped, in order to reduce size, and aid quick development.

AEL 5.0 (coming soon)

AEL file systems are now produced using the alip-ael project.

AEL 4.0

The master branch of the AEL project is currently tracking the ALIP generic-3 branch.

Download new images from http://www.linux-arm.org/git

Adding third party codes to AEL 4.0

Changes relative to AEL 3.0

• Based on the ALIP generic-3 branch. Please note that the AEL generic-2 branch will not be maintained once the new images have been released. Also, the AEL-ALIP master branch will be moved to generic-3. It will still be possible to build AEL-3.0 but the generic-2 branch must be manually selected.
• Thumb2 file systems now built for NEON, rather than just VFP
• AEL-ALIP file systems now build & install eglibc system libraries, rather than using the toolchain libraries.

AEL 3.0

www.arm.com::Linux Operating System Download provides ready made file system images.
These are based on the source code available at www.linux.onarm.com.
A seperate matrix project, the AEL project, is used to tailor these packages to the ARM supplied development boards.
The project may be cloned from git://linux-arm.org/public/projects/AEL
Note that the matrix/scratchbox method allows thumb2 and other variants to be built.
Note re the matrix build system

Python & ALIP file systems

scratchbox python may prove inadequate for some builds.

If upgrading, one can avoid many problems by building the python installed on the target as the scratchbox python.

Note that zlib is installed first since building xulrunner requires python to have zlib support.

If not present the xulrunner build will fail with "Import Error: No module name zlib"

sbox-alip-ael > sb-conf setup host --compiler=host-gcc --devkits=qemu:doctools:perl:git --cputransp=qemu-i386-sb
sbox-alip-ael > sb-conf select host
sbox-host > sb-conf install --etc --devkit
sbox-host > cd ~
sbox-host > git clone git://linux.onarm.com/git/generic/source/zlib
sbox-host > cd zlib
sbox-host > configure --prefix=/host_user
sbox-host > make
sbox-host > fakeroot make install
sbox-host > git clone git://linux.onarm.com/git/generic/source/python2.6.git
sbox-host > cd python2.6 
sbox-host > configure --prefix=/host_user
sbox-host > make
sbox-host > fakeroot make install
sbox-host > sb-conf select alip-ael
sbox-alip-ael >

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AEL 2.5.0 and earlier

Format

AEL 2.5.0 and earlier were based on a Configurator.
The configurator consisted of a set of Debian packages, together with some perl scripts to allow users to select which packages are built into the file system produced.
Both the images and the configurator were primarily intended for use with ARM supplied development boards and models. Caveat The file systems produced were considerably reduced from a standard "desktop" file system.

Configurator Notes

Known Problems With ARM_Embedded_Linux-2.4.0

xorg

The file system now uses packages based on xorg-7.1.0.
This takes more notice of it's config files than the previous version, based on X11R6?-4.2.1.
Recommended depths & resolutions for ARM supplied development boards are

Board	Depth	Resolution
IntegratorCP	16bpp	640x480
VersatilePB	16bpp	800x600

The supplied etc/X11/xorg.conf should be edited accordingly.
Other resolutions and depths may require changes to the file system and/or kernel.
Attached is a kernel patch to allow VersatilePB to use 8bpp, 800x600.

-- PeterPearse - 23 Aug 2007