Posted by Godwin Maben on April 10, 2009
I was always wondering on, what are the key aspects of IEEE1801 UPF2.0 standard, which stands tall as compared to the current UPF1.0 Standard. Remember current UPF constructs are sufficient to define a power intent of a design almost completely.
But with UPF2.0, there are many things which are good to have in terms of defining the power intent of the design more efficiently.
In my opinion following concepts are quite good in defining the intent more efficiently.
(a) Concept of “SIMSTATES” : With this concept, user can define different simulation semantics for a power domain, one example of this is “ Corrupt on Activity”
(b) Supply Sets: This gives us a collection of “Multiple Supply Nets that form a complete power source of a design element” . Beauty of this is, we can define a function(power/ground/deepnwell..etc) for a supply set and also define a reference ground for the set.
(c ) Update Options: Gives us an opportunity to refine the power intent on the fly progressively
(d) Query Functions: Helps us in querying design objects and power intent, few such examples include “query_mapped_isolation_cell”, “query_pin_related_supply”….etc. In my opinion this streamlines querying independent of the tools and vendor.
(e) State Transitions: Specifying legal/illegal state transitions for power domains and supply nets.
If you monitor the way power intent specification standard is progressing, I wont be surprised if one day, we have a “function intent specification”, which will go along with RTL to define the functional/architectural intent!!, may be it will be called “Unified Function Format(UFF)” or “Unified Architecture Format”.
- Godwin Maben