Fast Models Reference Manual - ARM Information Center

AEM ARMv7-A specifics
A.2 Debug architecture support
In default configuration, the model implements ARMv7 debug architecture, as described in Part
C of the ARM Architecture Reference Manual ARMv7-A and ARMv7-R Edition.
When the model is configured to include support for the Virtualization extension, then the
model also implements ARM Debug Architecture v7.1.
A.2.1
Invasive debug
This section describes the invasive debug features that are available:
• Debug events
• Debug exceptions
• Debug state
• Invasive debug authentication.
Debug events
All software debug events are supported, that is, BKPT instruction, breakpoints, watchpoints
and vector catch.
Only one halting debug event is currently handled. External debug request is triggered by means
of the signal port edgrq. The halting debug events, Halt Request and OS Unlock Catch are not
currently implemented.
The external signal port is not connected in the VE platform.
Debug exceptions
Monitor debug mode is available in the AEM when configured through the DBGDSCR. In this
mode software debug events cause a debug exception resulting in either:
• a pre-fetch abort exception in the case of a BKPT instruction event, breakpoint event and
vector catch event
• a data abort exception in the case of a watchpoint event.
Debug state
You can configure the AEM to enter debug state in the case of a software debug event through
the DBGDCSR. Halting debug events always enter debug state if debug is both enabled and
permitted.
Invasive debug authentication
Debug is enabled or disabled by two signals on the external debug interface, dbgen and spiden.
Signal ports for non-invasive debug, niden and spniden, are present but are currently unused.
The external signal interface is not connected in the VE platform.
A.2.2
Non-invasive debug
Non-invasive debug is currently not supported.
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