roscd code_sourcery_arm_gnueabi make # downloads the toolchain binary. make install # installs into the /usr/___ directories. make uninstall # removes the toolchain from your system.
Once you have the toolchain installed, you may need to make it ros-ready (i.e. install apr, apr-util, log4cxx, boost) using the instructions for a toolchain bridge.
Eros provides a ready made toolchain module you can select to globally configure your ros environment. To globally configure your ros environment to use this toolchain:
rostoolchain select code_sourcery/arm-none-linux-gnueabi
Depending on what kind of development you wish to do:
Partial cross : embedded development without linking to the core ros libraries.
Full cross : cross-compile both ros and your packages.
Platform (Cpu) Configuration
You'll probably want to also globally configure your platform module as well (i.e. the $ROS_ROOT/rosconfig.cmake file). A useful example file for arm cores can be found in 'eros_platforms/library/arm/arm1176jzf-s.cmake'.