Saturday, November 12, 2011

Register Automation using VMM/UVM RAL

VMM RAL had been around for a long time is a very powerful feature to verify your hardware registers it provides the user with features like name based register access, mirroring registers, back door access, functional coverage and the predefined tests .The same set of VMM RAL features are available in UVM as well. One of the features which i was impressed with was auto mirror update feature which updates the RAL mirror on register changes through backdoor, this feature is handy when you do your register read/write through an embedded processor instead of regular front door access and you want to synchronize your test bench based on the value of register mirrors.

Accellera has come up with standards like IPXACT and system RDL to define your registers, this enables vendor independence to the users and most of generator tools are converging on these standards. The ideal way of automating your register is to define the registers using the standards and use generators from vendors to auto generate the RTL, firmware code, documentation and system Verilog RAL classes.

Quick survey on the tools supporting the standards indicated that there are many players in this space. One aspect which did not sink into my head was why the entire register solution can’t be packaged with the simulator itself, so that the user does not have to make additional investment on another tool. May be it might be on the product road map for the simulators.

With VMM RAL being adopted in UVM, definitely the user base for RAL is going to increase.

Saturday, November 5, 2011

Downside of being the “guinea pig” for adopting the latest buzz words in verification !!!

Adopting the latest’s verification methods and trends is my hobby right from the year 2002 and I have been continuing this till date. Adoption includes adopting new feature in the tool/methodology or construct in a language to adopting a new method of verification which could potentially improve the productivity, results in finding more bugs and improve the maintenance of the test bench. The upside of this hobby is you keep yourself updated with new trends in the market and become the early bird in adopting a trend. Evaluating the down side of this hobby did not come to my mind till one of my friends put an insight into my mind, adopting all the marketing buzz words can become fatal.

His words of wisdom made me rewind my thoughts on all the possible trends I tried to adopt over years. Few common trends i observed in each of the adoption are as follows

1) New code development is only 10% rest of the effort is making enhancements to the current environment. Tool vendors do not take this equation and end up facing gaps in the feature offering.

2) Being the first one to adopt a new verification trend, be prepared to face tool bugs, and sometimes even showstopper bugs.

3) Not all people have the practice of updating themselves to the latest trend and are more than happy to implement things with outdated technology. These people find it difficult to adapt to changes, we have to carry this type of people with us.


There have been feature or tools i have adopted early with became highly popular over years and some features i adopted early don’t even exist now.