The Abstraction Model – Is It More, Is It Less?

Oski Technology provides formal verification services to leading semiconductor companies to verify complex design blocks that are difficult to verify using simulation. In our projects, we often write Abstraction Models to overcome formal complexity barriers that would otherwise render formal verification results inconclusive. For example, for the open-source Sun OpenSparc T1 design, verifying a data transport checker without the Abstraction Models would have taken an estimated 991 days of run-time, but only 147 seconds with the Abstraction Models, a significant speed-up of 600,000X. With Abstraction Models and other similar techniques, formal verification can be used as sign-off criteria in the verification flow; Oski has helped many customers adopt and develop formal sign-off flows.

Customers often have the misconception that Abstraction Models reduce design behaviors which makes the formal verification task easier and allow it to finish sooner. They worry about missing bugs with Abstraction Models. In reality however, Abstraction Models do not reduce design behaviors; to the contrary they add to design behaviors by adding new reset states, and/or state transitions. As a result, no bug will be missed. More is less because when more behaviors are added purposefully and artfully, they can actually make the formal verification job easier for the tools and take less time. This might be counter-intuitive and may take some time and practice to get used to. But if one understands the concept and techniques of writing and using Abstraction Models, formal verification can be put to much better and broader use.

Because each design is different, custom Abstraction Models are needed for each design. There is no Abstraction Model VIP one can purchase to fit all kinds of designs. The good news is that knowing when and how to use Abstraction Models is very much a teachable, learnable skill. We teach our customers about Abstraction Models in our projects and we include the Abstraction Models we develop for the project as source code so customers can write their own Abstraction Models in future projects.

Decoding Formal Club Meeting: Abstraction Models, January 23

Now is your opportunity to learn more about abstraction models. Vigyan Singhal Oski CEO, will be presenting a talk on Abstraction Models in the upcoming Oski Decoding Formal Club event on Jan. 23rd, 1:00 PM – 3:30 PM. The talk will cover what Abstraction Models are, when you know you need them, how to write them and how to use them, using real examples. We will also feature a guest presentation from Broadcom discussing techniques on formal data integrity verification using scoreboard. See below to pre-register for this event.

Don’t miss this opportunity to come and learn more about Abstraction Models so your formal verification runs will take less time.

Registration is now closed for this event. Please subscribe to our newsletter to receive notice of the next Decoding Formal Club meeting.

For Abstraction Models, More is Less!