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Introduction

If you are already an experienced verification engineer familiar with SystemVerilog (or Vera or e or C++) you will probably have little trouble learning the UVM. This article, however, is aimed at a different audience; at those VHDL and Verilog engineers who feel they probably need to do a better job at functional verification, but have not yet found the time or the courage to take a deep dive into SystemVerilog.

In this article we take a look at UVM by considering how you would use UVM to represent ideas familiar to the Verilog or VHDL users, ideas such as design entities, modules, processes, ports, parameters, generics and configuration. Rather than trying to demonstrate all the fancy features of UVM, we will deliberately restrict ourselves to a small, well-behaved subset of the UVM library, which I will informally refer to as Easier UVM.

As a language, SystemVerilog provides the mechanisms you need to create verification components for checking, coverage collection, and stimulus generation, and to modify the behavior of those components as you write specific tests. But SystemVerilog provides more than this, so much more in fact that the learning curve can be daunting for non-specialists. If you are not a verification specialist, what you might need is just enough SystemVerilog to get you going so you can start to benefit from VIP re-use and as a base on which to build as your experience and confidence increase. The aim of Easier UVM is to introduce you to some coding guidelines for UVM that will enable you to do just that.

Easier UVM is not yet another verification methodology. It is UVM. The point is to somewhat restrict the range of features being used in order to make life easier for the novice. In short, where there are multiple ways of doing things we will pick just one, hopefully the cleanest and most well-behaved (though not necessarily your favorite if you happen to be a verification expert already).

If the subject of constrained random coverage-driven verification is unfamiliar to you, you might like to start by reading the UVM Verification Primer.

Open each of the topics below to see a UVM concept presented in terms familiar to the Verilog or VHDL users:

• From Design Entities and Modules to the UVM Component
• The Various Kinds of UVM Component
• From HDL Processes to the UVM Run Phase
• From HDL Input and Output Ports to TLM Ports and Exports
• From VHDL Records to UVM Transactions
• From VHDL Generics and Verilog Parameters to UVM Configurations
• FAQs

Example

To get you started, we have put together an example written in the Easier UVM coding style that illustrates the points made above and demonstrates some of the new features added in UVM such as the end-of-test objection mechanism, callbacks, and the report catcher. We intend to build an expanded tutorial around this UVM example in due course, but in the meantime, enjoy!

UVM is here at last. This example runs unmodified using simulators from Cadence, Mentor, and Synopsys. Yippee!

Click here to download the source files for this example. In exchange, we will ask you to enter some personal details. To read about how we use your details, click here. On the registration form, you will be asked whether you want us to send you further information concerning other Doulos products and services in the subject area concerned.

Previous:  From OVM to UVM: Getting Started with UVM - A First Example   

LINKS

Easier UVM Coding Guidelines

• Introduction to the Easier UVM Coding Guidelines
• Summary of the Easier UVM Coding Guidelines
• Detailed Explanation of the Easier UVM Coding Guidelines
• Easier UVM Glossary
• Easier UVM Coding Guidelines - Download

Easier UVM - Deeper Explanations

• Coverage-Driven Verification Methodology
• Requests, Responses, Layered Protocols and Layered Agents
• How to Access a Parameterized SystemVerilog Interface from UVM

Easier UVM Code Generator

• Easier UVM Coding Guidelines - Download
• Easier UVM Code Generator - Tutorial Part 1: Getting Started
• Easier UVM Code Generator - Tutorial Part 2: Adding User-Defined Code
• Easier UVM Code Generator - Tutorial Part 3: Adding the Register Layer
• Easier UVM Code Generator - Tutorial Part 4: Hierarchical Verification Environments
• Easier UVM Code Generator - Tutorial Part 5: Split Transactors
• Easier UVM Code Generator - Frequently Asked Questions (FAQ)
• Easier UVM Code Generator - Reference Guide

Easier UVM Video Tutorial

• Introducing Easier UVM
• Easier UVM - The Big Picture
• Key Concepts of the Easier UVM Code Generator
• Running Easier UVM in EDA Playground
• Easier UVM - Components and Phases
• Easier UVM - Configuration
• TLM Connections in UVM
• Easier UVM - Transaction Classes
• Easier UVM - Sequences
• Easier UVM - Tests
• Easier UVM - Reporting
• Easier UVM - Register Layer
• Easier UVM - Parameterized Interfaces
• Easier UVM - Scoreboards
• The Finer Points of UVM Sequences (Recorded Webinar)
• UVM Run-Time Phasing (Recorded Webinar)
• A YouTube playlist with all the above videos and more

Easier UVM Paper and Poster

• Easier UVM - Coding Guidelines and Code Generation - as presented at DVCon 2014

Easier UVM Examples Ready-to-Run on EDA Playground

• Minimal example with driver
• Minimal example with coverage in a subscriber as well as driver and monitor.
• Minimal example with register sequence and register block
• Example with four interfaces/agents, two of which use a register model.
• Minimal example with dual-top modules and split transactors
• Minimal example showing a UVM sequence getting information from the config database
• Minimal example showing features of objections and the command line processor
• Minimal example showing the reporting features of UVM.
• Example that drops an objection when coverage exceeds some threshold
• Example that sends a response transaction from the driver back to the uvm_reg_adapter
• Example that uses a frontdoor sequence to pass a response object back to the register sequence that called read/write
• Example of a parameterized interface generated from an Easier UVM interface template file
• Example that pulls in a user-defined parameterized interface
• Example of a reference model with the Syosil scoreboard

 

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