Root Filesystem Building Tool

This software package consists of a set of scripts and packages for building a minimal Linux distribution. This system is used at Diamond Light Source (DLS) for a number of ARM and PowerPC based embedded systems.

This system is very much in the spirit of buildroot, not as well developed, quite a lot smaller, and about the same age! Alas, the current version of this tool has a number of DLS dependencies hard-wired, but this is published in the hope that it may be of more general use.

A target configuration is a simple set of assignments in makefile macro syntax, for example:

TOOLCHAIN = arm-xscale

PACKAGES += busybox

CONSOLE_TTY = ttyS0
CONSOLE_BAUD = 115200

Building this, with the command ./rootfs TARGET=minimal, will create a complete bootable root file system using the default busybox configuration with the controlling terminal as configured.

The resulting build is pretty small, less than 4MB. A smaller build could be achieved with the use of uClibc, but we've not had a requirement for this.

To get started:

1. Run make -C docs to build the detailed documentation. You are welcome to contact the author with questions and bug reports.

2. Copy CONFIG.example to CONFIG.local and edit ROOTFS_ROOT and TAR_DIRS to point to sensible locations.

   ROOTFS_ROOT

   The entire build process will be done under this directory, and the final build will be placed in:

   $(ROOTFS_ROOT)/targets/$(TARGET)/image/imagefile.cpio
   

   TAR_DIRS

   The rootfs build scripts will not make any attempt to download the sources, instead they need to be available in one of the directories defined by this symbol.

3. Populate $(TAR_DIRS). As a minimum, the following files (as of the time of writing) will need to be downloaded from their appropriate download locations:

   autoconf-2.69.tar.gz, automake-1.15.tar.gz, libtool-2.4.6.tar.gz, m4-1.4.17.tar.gz, pkg-config-0.28.tar.gz, busybox-1.23.2.tar.bz2

   together with the sources for any other packages needed.

4. Run ./rootfs make.

As this tool has been developed to run on an enterprise system with quite old tools (Red Hat Enterprise Linux 6), it is necessary to make our own builds of a number of standard tools to help with building some packages.