Provision of debug via a separate ring bus in a data processing apparatus

摘要

A data processing apparatus is provided having a plurality of functional units. At least one of the functional units is operable to perform data processing operations and at least a subset of the plurality of functional units have at least one of a respective co-processor register for storing configuration data and a respective debug register for storing debug data. A debug controller outputs debug data and co-ordinates debug operations. A configuration ring-bus provides a ring path for communication of configuration instructions between a first ring sequence of the plurality of functional units and a debug ring-bus provides a ring path for communication of the debug data between a second ring sequence of the plurality of functional units. Separate provision of the debug ring-bus and the configuration ring-bus provides independent access to the co-processor register and to the debug register.