Verification Academy

Search form

My Account Menu

  • Register
  • Log In
  • Topics
  • Courses
  • Forums
  • Patterns Library
  • Cookbooks
  • Events
  • More
  • All Topics
    The Verification Academy offers users multiple entry points to find the information they need. One of these entry points is through Topic collections. These topics are industry standards that all design and verification engineers should recognize. While we continue to add new topics, users are encourage to further refine collection information to meet their specific interests.
    • Languages & Standards

      • Portable Test and Stimulus
      • Functional Safety
      • Design & Verification Languages
    • Methodologies

      • UVM - Universal Verification Methodology
      • UVM Framework
      • UVM Connect
      • FPGA Verification
      • Coverage
    • Techniques & Tools

      • Verification IQ
      • Verification IP
      • Static-Based Techniques
      • Simulation-Based Techniques
      • Planning, Measurement, and Analysis
      • Formal-Based Techniques
      • Debug
      • Acceleration
  • All Courses
    The Verification Academy is organized into a collection of free online courses, focusing on various key aspects of advanced functional verification. Each course consists of multiple sessions—allowing the participant to pick and choose specific topics of interest, as well as revisit any specific topics for future reference. After completing a specific course, the participant should be armed with enough knowledge to then understand the necessary steps required for maturing their own organization’s skills and infrastructure on the specific topic of interest. The Verification Academy will provide you with a unique opportunity to develop an understanding of how to mature your organization’s processes so that you can then reap the benefits that advanced functional verification offers.
    • Universal Verification Methodology (UVM)

      • Introduction to UVM
      • UVM Basics
      • Advanced UVM
      • UVM Connect
      • UVM Debug
      • UVMF - One Bite at a Time
    • Featured Courses

      • Introduction to ISO 26262
      • Introduction to DO-254
      • Clock-Domain Crossing Verification
      • Portable Stimulus Basics
      • Power Aware CDC Verification
      • Power Aware Verification
      • SystemVerilog OOP for UVM Verification
    • Additional Courses

      • Assertion-Based Verification
      • An Introduction to Unit Testing with SVUnit
      • Evolving FPGA Verification Capabilities
      • Metrics in SoC Verification
      • SystemVerilog Testbench Acceleration
      • Testbench Co-Emulation: SystemC & TLM-2.0
      • Verification Planning and Management
      • VHDL-2008 Why It Matters
    • Formal-Based Techniques

      • Formal Assertion-Based Verification
      • Formal-Based Technology: Automatic Formal Solutions
      • Formal Coverage
      • Getting Started with Formal-Based Technology
      • Handling Inconclusive Assertions in Formal Verification
      • Sequential Logic Equivalence Checking
    • Analog/Mixed Signal

      • AMS Design Configuration Schemes
      • Improve AMS Verification Performance
      • Improve AMS Verification Quality
  • All Forum Topics
    The Verification Community is eager to answer your UVM, SystemVerilog and Coverage related questions. We encourage you to take an active role in the Forums by answering and commenting to any questions that you are able to.
    • UVM Forum

      • Active Questions
      • Solutions
      • Replies
      • No Replies
      • Search
      • UVM Forum
    • SystemVerilog Forum

      • Active Questions
      • Solutions
      • Replies
      • No Replies
      • Search
      • SystemVerilog Forum
    • Coverage Forum

      • Active Questions
      • Solutions
      • Replies
      • No Replies
      • Search
      • Coverage Forum
    • Additional Forums

      • Announcements
      • Downloads
      • OVM Forum
  • Patterns Library
    The Verification Academy Patterns Library contains a collection of solutions to many of today's verification problems. The patterns contained in the library span across the entire domain of verification (i.e., from specification to methodology to implementation—and across multiple verification engines such as formal, simulation, and emulation).
    • Implementation Patterns

      • Environment Patterns
      • Stimulus Patterns
      • Analysis Patterns
      • All Implementation Patterns
    • Specification Patterns

      • Occurrence Property Patterns
      • Order Property Patterns
      • All Specification Patterns
    • Pattern Resources

      • Start Here - Patterns Library Overview
      • Whitepaper - Taking Reuse to the Next Level
      • Verification Horizons - The Verification Academy Patterns Library
      • Contribute a Pattern to the Library
  • All Cookbooks
    Find all the methodology you need in this comprehensive and vast collection. The UVM and Coverage Cookbooks contain dozens of informative, executable articles covering all aspects of UVM and Coverage.
    • UVM Cookbook

      • UVM Basics
      • Testbench Architecture
      • DUT-Testbench Connections
      • Configuring a Test Environment
      • Analysis Components & Techniques
      • End Of Test Mechanisms
      • Sequences
      • The UVM Messaging System
      • Other Stimulus Techniques
      • Register Abstraction Layer
      • Testbench Acceleration through Co-Emulation
      • Debug of SV and UVM
      • UVM Connect - SV-SystemC interoperability
      • UVM Versions and Compatibility
      • UVM Cookbook
    • Coding Guidelines & Deployment

      • Code Examples
      • UVM Verification Component
      • Package/Organization
      • Questa/Compiling UVM
      • SystemVerilog Guidelines
      • SystemVerilog Performance Guidelines
      • UVM Guidelines
      • UVM Performance Guidelines
    • Coverage Cookbook

      • Introduction
      • What is Coverage?
      • Kinds of Coverage
      • Specification to Testplan
      • Testplan to Functional Coverage
      • Bus Protocol Coverage
      • Block Level Coverage
      • Datapath Coverage
      • SoC Coverage Example
      • Requirements Writing Guidelines
      • Coverage Cookbook
  • All Events
    No one argues that the challenges of verification are growing exponentially. What is needed to meet these challenges are tools, methodologies and processes that can help you transform your verification environment. These recorded seminars from Verification Academy trainers and users provide examples for adoption of new technologies and how to evolve your verification process.
    • Featured & On-Demand

      • Static & Formal - Israel | May 31st
      • VA Live - Multiple Dates & Locations
      • Interconnect Formal
      • Formal and the Next Normal
      • Formal Verification Made Easy
      • Data Independence and Non-Determinism
      • Exhaustive Scoreboarding
      • Visualizer Debug Environment
      • Webinar Calendar
    • On-Demand Library

      • SystemVerilog Assertions
      • Practical Flows for Continuous Integration
      • Continuous Integration
      • Questa Verification IQ
      • Avery & Siemens VIP
      • Protocol and Memory Interface Verification
      • HPC Protocols & Memories
      • Preparing for PCIe 6.0: Parts I & II
      • High Defect Coverage
      • SoC Design & Functional Safety Flow
      • Complex Safety Architectures
      • All On-Demand Recordings
    • Recording Archive

      • Lint vs Formal AutoCheck
      • FPGA Design Challenges
      • Design Solutions as a Sleep Aid
      • Fix FPGA Failures Faster
      • CDC and RDC Assist
      • The Dog ate my RTL
      • Questa Lint & CDC
      • Hierarchical CDC+RDC
      • Improving Initial RTL Quality
      • CDC Philosophy
      • Hardware Emulation Productivity
      • The Three Pillars of Intent-Focused Insight
      • All Webinar Topics
    • Conferences & WRG

      • 2022 Functional Verification Study
      • Improving Your SystemVerilog & UVM Skills
      • Automotive Functional Safety Forum
      • Aerospace & Defense Tech Day
      • Siemens EDA Functional Verification
      • Industry Data & Surveys
      • DVCon 2023
      • DVCon 2022
      • DVCon 2021
      • Osmosis 2022
      • All Conferences
    • Siemens EDA Learning Center

      • EDA Xcelerator Academy(Learning Services) Verification Training, Badging and Certification
      • View all Xcelerator Academy classes
  • About Verification Academy
    The Verification Academy will provide you with a unique opportunity to develop an understanding of how to mature your organization's processes so that you can then reap the benefits that advanced functional verification offers.
    • Blog & News

      • Verification IQ
      • Verification Horizons Blog
      • Technical Resources
    • Verification Horizons Publication

      • Verification Horizons - March 2023
      • Verification Horizons - December 2022
      • Verification Horizons - July 2022
      • Issue Archive
    • About Us

      • Verification Academy Overview
      • Subject Matter Experts
      • Academy News
      • Contact Us
    • Training

      • Learning @OneGlance (PDF)
      • SystemVerilog & UVM Classes
      • Siemens EDA Classes
Ask a Question
UVM
  • Home
  • Forums
  • UVM
  • uvm_backdoor and uvm_frontdoor parallel access to a register

uvm_backdoor and uvm_frontdoor parallel access to a register

UVM 6740
#uvm 278 #UVM #RAL 59
debdip microsemi
debdip microsemi
Full Access
2 posts
June 21, 2018 at 8:53 am

Hello,
I am having one scenario where reg write is happening thru frontdoor access in one uvm_component run_phase. We know It takes couple of clock cycles to complete. For example I am initiating write at 50ns sim time and it is completing at 100ns. At 80ns I am seeing the DUT register signal is going 0->1 as I am writing 1 to that register (reset value is 0) .
In another uvm_component run_phase I am reading the particular register signal using backdoor access for every clock cycle. But the read is skipping the backdoor access(50ns to 100ns cycle) during the write process of the same register. Is it possible to read the register at 80ns at the clock edge?.Please help.

Thanks.

Replies

Log In to Reply
chr_sue
chr_sue
Full Access
3890 posts
June 21, 2018 at 10:46 am

In reply to debdip microsemi:

First, you are mixing 2 things frontdoor sequence and frontdoor access. These are 2 different things.
second, you have a vild value in your register if the access has been completed. But you want to read via backdoor when the frontdoor access is still not ready. The UVM mechanism is helping you to avoid such an invalid access.

bbensonk
bbensonk
Full Access
2 posts
March 25, 2021 at 1:11 pm

In reply to chr_sue:

I have a similar issue. I am doing a front-door field write which takes a long time to return. While that is happening I want to poll the DUT register bit with back-door field reads (peek) so I can verify a Read Write Self Clear register is working. Is there a way to do back-door peeks in parallel with front-door writes?

Thanks.

chr_sue
chr_sue
Full Access
3890 posts
March 25, 2021 at 2:17 pm

In reply to bbensonk:

This should be possible. But I believe it is useless. You do not know what you are reading via backdoor.

bbensonk
bbensonk
Full Access
2 posts
March 25, 2021 at 2:43 pm

In reply to chr_sue:

Not sure what you mean, so maybe this needs more context.

In our bench, for each register field with a corresponding DUT memory element we do a setup call like this.

reg.add_hdl_path_slice(.name("DUT_reg_name"), .offset(bit_num), .size(1));

When we do a field.peek() call to the corresponding register field we are able to see the value which corresponds to that memory element in the waves. This allows us to write a sequence which does a field.write() front-door access. Then a loop polls with field.peek() to verify that the field asserts afterwards and that the DUT subsequently cleared it. That is working code.

The problem is our new DUT has an indirect register access. We changed our register adapter to work properly, it just takes longer. Now the DUT register memory element asserts and clears before the front-door field.write() even finishes.

That is why we need a back-door peek to work separately from the front-door write. This is a specific register test. The value is verified 0 through peek before testing this register. If a fork is used the polling loop can begin at the same time as the front-door write. So there's no chance of missing the DUT memory element assertion.

It would be helpful if you have any ideas on how it might be possible. Thanks.

chr_sue
chr_sue
Full Access
3890 posts
March 27, 2021 at 2:33 am

In reply to bbensonk:

I believe it is quite easy. You are starting a frontdoor . This will modify the content of your registers. Doing a backdoor peek in parallel shows you thhe old or the updated value. You cannot control this.

Siemens Digital Industries Software

Siemens Digital Industries Software

#TodayMeetsTomorrow

Portfolio

  • Cloud
  • Mendix
  • Electronic Design Automation
  • MindSphere
  • Design, Manufacturing and PLM Software
  • View all Portfolio

Explore

  • Community
  • Blog
  • Online Store

Siemens

  • About Us
  • Careers
  • Events
  • News and Press
  • Customer Stories
  • Partners
  • Trust Center

Contact

  • VA - Contact Us
  • PLM - Contact Us
  • EDA - Contact Us
  • Worldwide Offices
  • Support Center
  • Give us Feedback
© Siemens 2023
Terms of Use Privacy Statement Cookie Statement DMCA