The openmote project has information posted here:
In order to get your openmote system set up, please start with the appropriate kickstart page but do not continue where it lists the TelosB hardware in the "Now with real hardware" section.
Once the general software is installed, the toolchain for the openmote should be installed. The openmote uses a CC2538 chip which contains an arm M3. Follow the instructions to set up a development environment for the firmware as listed here:
Project Leads
OpenWSN support
The OpenMoteCC2538 is fully supported in OpenWSN.
The OpenWSN builders build the OpenMoteCC2538 firmware nightly:
Under construction
TODO Pere Tuset.