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

Introduction to the ARM Debug Architecture
C1.2.3 Major differences between the ARMv6 and ARMv7 Debug architectures
ARMv6 is the first version of the ARM architecture to include debug. The introduction of the ARM
architecture Security Extensions extended the ARMv6 Debug architecture:
ARMv6 processors without the Security Extensions implement v6 Debug
ARMv6 processors with the Security Extensions implement v6.1 Debug.
ARMv7 introduces additional extensions to support developments in the debug environment.
The main change in the Debug architecture is the specification of new forms of external debug interface.
ARMv6 Debug does not require a particular debug interface, but can be implemented with access from a
JTAG interface as defined in IEEE Standard Test Access Port and Boundary Scan Architecture (JTAG).
However, systems such as the ARM CoreSight architecture require changes in the debug interface. For
more information about the CoreSight architecture see the CoreSight Architecture Specification.
ARMv7 Debug addresses some of the aims of the CoreSight architecture, such as a more system-centric
view of debug, and improved debug of powered-down systems.
v7 Debug also introduces an architecture extension to provide performance monitors.
C1.2.4 Summary of the ARM debug component descriptions
Table C1-1 shows the main components of v7 Debug, and where they are described.
Component Status Type Reference
For more information, see:
Chapter C10 Debug Registers Reference
Appendix A Recommended External Debug Interface.
Table C1-1 v7 Debug subarchitectures
Run-control Debug Required Invasive Chapter C2 Invasive Debug Authentication
Chapter C3 Debug Events
Chapter C4 Debug Exceptions
Chapter C5 Debug State
Chapter C6 Debug Register Interfaces
Trace Optional Non-invasive a Trace on page C1-5
Sample-based profiling Optional Non-invasive a Chapter C8 Sample-based Profiling
Performance monitors Optional Non-invasive a Chapter C9 Performance Monitors
a. For information about authentication of these components see Chapter C7 Non-invasive Debug Authentication.
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