|Home > Introduction > Non-CADI sync watchpoints > Controlling and observing the syncLevel|
CADI watchpoints automatically register and unregister for their required syncLevel
(POST_INSN_IO). All other use cases must explicitly register and unregister for the syncLevel they require.
Users of syncLevel write to a set of non-architectural processor registers in the CADI and SCADI interface to register and unregister for specific syncLevels. Processor registers are more suitable than CADI parameters for exposing an interface that has side effects on writes and where values might change spontaneously.
This is the exposed interface to control and observe the value of syncLevel.
All these registers are in the CADI/SCADI register group
Simulation for each CT processor that contains non-architectural,
simulator-specific registers. All are 32-bit integer registers. Users of syncLevel write to
these registers to register and unregister for the syncLevel they require:
These registers are only for debugging and visibility in the debugger, and syncLevel users do not usually access them at all:
min_sync_levelparameter (as follows). Read-write.
The *Register and *Unregister registers are for syncLevel users to register
and unregister themselves, by writing the value 0 to them. Changes to the syncLevel become
effective at the next stop event checkpoint. In addition, syncLevel users can write to these
registers any time before simulation is running, for example from the
init() simulation phase. The change then takes effect immediately
when the simulation is run.
The other registers are only present to make the debugging of these mechanisms and their users easier. The syncLevel enables you to see what kind of performance you can expect from the model. You must treat access to these registers as read-only. You may writing to them, however, to permit debugging the syncLevel mechanisms.
These registers are not memory (or CPnn-) mapped anywhere, and are not accessible to target programs.
In addition to this debug register interface, there is a CADI parameter that can influence the syncLevel:
min_sync_level (default=0, type=int, runtime=true)
This parameter enables you to control the minimum syncLevel by the CADI
parameter interface. This is not the intended primary interface to control the syncLevel
because it does not enable multiple independent syncLevel users to indicate their
requirements to the simulator. It is primarily for debugging purposes and for situations
where a single global setting of syncLevel is sufficient. You may change this parameter at
runtime, and changes become effective on the next stop event checkpoint. Reading this
parameter value returns the
min_sync_level, not the current
syncLevel. This parameter is only an additional way of controlling the syncLevel and
controls the same mechanisms as the register interface.