ARM Architecture Reference Manual ARMv7-A and ARMv7-R edition

Performance Monitors
C9.6 Interaction with trace
It is IMPLEMENTATION DEFINED whether counter events are exported to a trace macrocell or other external
monitoring agents to provide triggering information. The form of the exporting is also IMPLEMENTATION
DEFINED. If implemented, this exporting might be enabled as part of the performance monitoring control
functionality.
Similarly, ARM recommends system designers to include a mechanism for importing a set of external
events to be counted, but such a feature is IMPLEMENTATION DEFINED. When implemented, this feature
enables the trace module to pass in events to be counted.
C9-8 Copyright © 1996-1998, 2000, 2004-2008 ARM Limited. All rights reserved. ARM DDI 0406B