In reply to verif_learner:
In reply to cgales:
cgales,
i wouldn’t fully agree with above though in most cases we should aim for this level of prediction.
In many cases, DUT uses very sophisticated algorithms and not only that many times the response will depend on how it is implemented (3 pipeline vs 4 pipeline internally).
So, the predictor has to not only implement the same complex algorithm (which is fine) but has also to mimic exact internals of DUT implementation. The second part is a pain and designer can change design anytime which is difficult to track.
So, what do we do?
If overall sequence is known at the output then we have safely used it. For example, message-in and message-out without worrying about how the packet chunks within message come out.
Normally, we evaluate all these and the cost complexity of implementing these and only then embark on implementation.
Anyway, my 2 cents and what we have used in multiple projects.
I agree with you. Sometimes we meet the challenge when
- Use a black-box IP
- Include complex algorithms
- With complex hierarchy
It’s really hard or may take huge effort to create golden model to predict the DUT output which data transfer through arbitrator or other unknown delay unit.