Setting up an RTEMS development environment for the Raspberry Pi

For this tutorial, I’m going to use Ubuntu 12.10 64 bit (updated to 14.10 LTS on April 2014). It is possible to do RTEMS development on almost any recent version of Linux, OS X, FreeBSD, and Windows. The RTEMS project provides pre-built compilers for all RTEMS architectures for a number of different development hosts including Fedora, CentOS, Suse, and Windows.

In addition to the pre-built compilers provided, there is a tool called RTEMS Source Builder that can download, patch, build, and install the compiler for you. This is what we will use for our Ubuntu setup.

You will need a RTEMS compiler, an ARM bare metal GCC will not do. I have posted some instructions for setting up the environment for Windows 7 here The following instructions start with a fresh install of Ubuntu 14.10 LTS 64 bit, with all updates applied.

Install Ubuntu prerequisites:

$ sudo apt-get install build-essential $ sudo apt-get install git $ sudo apt-get install python-dev $ sudo apt-get build-dep binutils gcc g++ gdb unzip git

Decide where the RTEMS tools and projects will reside

Here is the directory structure we will be using:

Path	Description
$HOME/development/rtems	The base directory for all RTEMS work
$HOME/development/rtems/compiler	Where the compiler is installed
$HOME/development/rtems/rtems-git	Where the RTEMS source code is checked out
$HOME/development/rtems/bsps	Where the RTEMS board support packages/libs are installed
$HOME/development/rtems/rtems-source-builder	The RTEMS source builder tool

Table 1. Directory Structure

Lets get started on this:

$ cd $HOME $ mkdir development $ cd development $ mkdir rtems $ cd rtems $ mkdir compiler

Build the RTEMS ARM cross compiler

The RTEMS Source builder documentation is located here:
http://www.rtems.org/ftp/pub/rtems/people/chrisj/source-builder/source-builder.html

1. Check out the RTEMS source builder tool

$ cd $HOME/development/rtems $ git clone git://git.rtems.org/chrisj/rtems-source-builder.git

2. Double check that all source builder dependencies are present:

$ cd rtems-source-builder $ source-builder/sb-check

This command should return the following:

RTEMS Source Builder environment is OK

The separate autotools build is no longer needed. The source builder will install them for you.

3. Build and install the toolchain

$ cd $HOME/development/rtems/rtems-source-builder/rtems $ ../source-builder/sb-set-builder \ --log=build-log.txt \ --prefix=$HOME/development/rtems/compiler/4.11 \ 4.11/rtems-arm

After the full download and build process, the toolchain is installed in:
$HOME/development/rtems/compiler/4.11

This whole process can take about 10 to 30 minutes depending on your computer specs. This has been run on a Raspberry Pi: Expect that to take all day!

4. Add the toolchain bin directory to your path, and you are ready to download and build RTEMS:

$ cd $HOME

Using your favorite editor, edit the .profile file and add the following line at the end of the file

PATH=$HOME/development/rtems/compiler/4.11/bin:$PATH

5. Now, logout and log back in. Open a terminal and type:

$ arm-rtems4.11-gcc -v

You should see the compiler version message. The compiler is installed and ready to use!

Next: How to download and build RTEMS