  A new Muon-to-Central-Trigger Processor Interface (MUCTPI) was built as part
of the upgrade of the ATLAS Level-1 trigger system for the next Run of the
Large Hadron Collider at CERN. The MUCTPI has 208 high-speed optical serial
links for receiving muon candidates from the muon trigger detectors. Three
high-end FPGAs are used for real-time processing of the muon candidates, for
sending trigger information to other parts of the trigger system, and for
sending summary information to the data acquisition and monitoring system. A
System-on-Chip (SoC) is used for the control, configuration and monitoring of
the hardware and the operation of the MUCTPI. The SoC consists of an FPGA part
and a processor system. The FPGA part provides communication with the
processing FPGAs, while the processor system runs software for communication
with the run-control system of the ATLAS experiment. In this paper we will
describe our experience with running CentOS Linux on the SoC. Cross-compilation
together with the existing framework for building of the ATLAS trigger and data
acquisition (TDAQ) software is being used in order to allow the deployment of
the TDAQ software directly on the SoC.
