Record cycle counter when payload began executing

[sqazi]

It would be very useful to have a feature that records a cycle count value when a payload begins executing. An internal cycle count register should increment continuously and be snapshotted into an accessible register whenever a payload begins executing. The script can then use that value to make comparisons between multiple payload executions.

[wkkuna]

Hi,
Sure thing, I'll have a look at it.

[wkkuna]

Hi,

We've just released changes that include the Payload Executor CSR reporting the first and last cycle of the payload execution.
The register payload_executor_exec_start reports on the first system clock cycle (counting from the last power cycle) of the payload execution.
There's also payload_executor_exec_stop that snapshots the first cycle the payload has stopped being executed.

After rebuilding your design and running payload execution (e.g. via hw_rowhammer.py) you should see additional:

Payload execution started at: 33791782680
Payload execution finished at: 33922040349
Total execution time (system clock cycles): 130257669

in your logs.
Let us know if this works for you.