Change In Methodology Of Verification and Validation Over The Years

There are huge amount of changes in verification methodologies over the years. There are various types of verification including the functional,speed path and performance verification. Verification is carried out in pre-silicon domain. While, validation is carried out in post-silicon domain. There are many changes in difficulty levels and methodologies of verification and valid ation over the years. Initally, Verification testbenches were implemented in verilog language. It did not had many features like callback, error injection and randomization. It was really difficult to add randomization. There was not any concrete methodology to implement the testbench. There was not any particular componetes defined in testbench. Creating the testbench was really difficult and unorganized. Years later, Verification moved to system verilog language. Verification using system verilog was organized as it had predifined components like generator, monitor and scoreeboard. Creating a verification enviournmment from scratch was not an issue as components were organized. Biggest issue in system verilog based enviournment was randomization. Randomization was needed to be done manually. It was not coming as part of verification enviournment. Later, Accelara group introduced the new methodoloy named as UVM. It was named as Universal Verification Methdology. It changed the way verification can be done completely. UVM had components like driver, monitor, sequencer and sequence item which had pre-defined way of implementing it. Also, randomization was an integral part of UVM verification methodology. It included both constarint driven verification and constraint random verification. Complete verification was coverage driven where verification closure was dependant on functional coverage, code coverage and FSM coverage. UVM made developing the verification component easy. Those are the main changes which took place into verification domain. Now, moving to the post silicon validation where there were many changes happened in terms of validation tools and methodologies. There were many types of validation including functional, coustomer based and speed path. Over the period of time, Validation teams created their own OS in order to validate all the components on motherboard. Validation was done with running real content on motherboard as well in terms of having the media, audio, graphics and video contect on motherboard. All these kinds of techniques changed the way validation and verification can be done on motherboard over the years.