New tools, languages, or methodologies can be an improvement over existing ones, or they can be enablers for something different. The recently approved Accellera Portable Stimulus Standard (PSS) can be either or both.
A lot has been written recently about how PSS can be combined with constrained random verification methodologies and that demonstrates the improvement aspect of the language.
It is to be expected that the major EDA companies are focusing on this because it gives them a good story to tell their existing verification users and an incremental sales opportunity. It also allows them to increase the value and differentiate their existing products from those of the competition, providing a strategic scaling opportunity. Unlike existing verification technologies that have been commoditized, PSS is still in its infancy and they can employ some degree of creativity in this space.
Integrating Portable Stimulus Standard (PSS) capabilities with the Universal Verification Methodology (UVM) is not the same as an integration between two languages.
In our previous column, Aileen Honess provided a backdrop as to why a team using Universal Verification Methodology (UVM) and SystemVerilog may want to extend their methodology by adding Portable Stimulus. By incorporating a constraint solver that understands not only combinatorial constraints but also the temporal aspects of a design, it becomes possible to generate more efficient tests that target a particular verification intent.
This blog will lay out the basic strategy for such an integration. It is important to note that integrating Portable Stimulus Standard (PSS) capabilities does not remove any of the capabilities that may already be in place. Existing testbenches will still work and they will continue to provide the same coverage. PSS adds new capabilities that become useful if you are having problems reaching the desired level of coverage or if you want to make test cases that are retargetable to emulation or can be used in chip bring-up. Read more
The point of standards is to bring an industry together, to avoid duplication of effort, and to reduce risks associated with adoption of technology that may lock a user into a single vendor. These are some of the reasons why Breker was glad to see the creation of the Portable Stimulus working group within Accellera and actively participated in it since its inception. We donated technology and invested more time and effort, as a percentage of company size, than any other player. We were also glad to see the release of version 1.0 of the standard at DAC in 2018 – a huge step for the industry.
But was it enough? Some standards are ratified having been developed and refined by a single company and successfully proliferated across an industry, prior to donation to a standards body. Others are designed by committee and therefore run the risk of an unproven body of work captured as a hard to change standard. Sometimes this works well, other times, less so. It is only after the fact that you know if the committee got it right. So far the Portable Stimulus Standard is being tested by a relatively large number of companies with success, but there are still missing elements for a scalable solution.
https://brekersystems.com/wp-content/uploads/2018/02/breker-logo4.png00Adnan Hamidhttps://brekersystems.com/wp-content/uploads/2018/02/breker-logo4.pngAdnan Hamid2019-03-14 15:25:422020-02-07 20:31:07Interim Solutions to the Standards Gap
Come one, come all to the first event of what we expect will be many –– Verification 3.0 Innovation Summit –– Tuesday, March 19, from 1 p.m. until 8 p.m. at the Levi’s Stadium Team Auditorium in Santa Clara, Calif.
Meant for all of you in the chip design verification community, the event will provide advanced technical content focused on semiconductor verification innovation. It will tackle topical subjects at a deep technical level and consider the latest thinking on critical verification methodology and technologies.
The start up and smaller verification companies are a source for a large proportion of verification innovation, but getting the word out on those innovations has become harder and harder. This new event represents a single opportunity to hear the latest from all of these companies in one shot.
All of us at Breker invite https://www.dvcon.org/ attendees to step into our booth (#701) and expect to be amazed. You will see practical demonstrations of our new feature-rich Trek5 with practical examples of how the Portable Stimulus Standard can be applied to accelerate UVM coding for complex blocks and Software Driven Verification (SDV) for large SoCs.
Yes, I’m proud of Trek5 and boasting a bit. Trek5 doesn’t stop at just Portable Stimulus synthesis –– it’s a complete solution that can be deployed across the verification spectrum. We went well beyond a simple conversion of PSS models to tests that required users to perform a lot of hand codinging. Instead, we automated the process, simplifying UVM stimulus, scoreboard and coverage authoring for complex blocks and SDV, complete with portable system services, for SoCs.
https://brekersystems.com/wp-content/uploads/2018/02/breker-logo4.png00Adnan Hamidhttps://brekersystems.com/wp-content/uploads/2018/02/breker-logo4.pngAdnan Hamid2019-02-21 15:16:582021-10-10 01:35:17What Can PSS Do For You? See Breker’s Demos of Trek5’s Capabilities at DVCon
Let me start by laying the cards on the table – the Portable Stimulus Standard (PSS) is a language, not a methodology. Tools are not methodologies. Languages ensure a well-ordered transfer of information from which tools can be constructed. A methodology is a way of systematically breaking down and solving a problem in a manageable manner. Tools can enable methodologies, and, over time, tools may help to manage a methodology once it has become standardized. No standard methodologies exist today for PSS, neither are the capabilities of tools defined by the language.
Portable Stimulus is a language that provides some degree of commonality between vendors in graph-based verification technologies that are delivered in the form of tools. Those tools can be used within existing methodologies or enable new ones to be created that may not have been supported by previous tools. When vendors provide capabilities beyond those defined in the standard, it is for the user community to decide how useful they are. The good ones will get wrapped into a future version of the standard, the less useful ones will be ignored. This is how languages evolve, especially for a language defined before a de facto standard emerged.
https://brekersystems.com/wp-content/uploads/2018/02/breker-logo4.png00Adnan Hamidhttps://brekersystems.com/wp-content/uploads/2018/02/breker-logo4.pngAdnan Hamid2019-01-15 15:21:142020-02-07 20:39:19Methodology, Language and Tools
Both UVM and PSS solutions deploy constraint solvers to create test cases, but that is where similarities end. Thankfully, they can work together to make everyone’s life a little easier.
Atomic actions are capabilities of functional blocks, but how do these things get done? That is the responsibility of the “exec” block.
How many times have we heard the old adage “If it sounds too good to be true, it probably is”? It almost becomes second nature to dismiss new ideas when the gains are talked up but the details are hidden. This is a trap that we find ourselves in at times with the Accellera Portable Stimulus Standard (PSS). There are so many things to be excited about that we sometimes forget to talk about the more mundane aspects of the technology.
We shall fix that in this blog and get into some of the details necessary for this technology to work.
Functional verification vendors have been talking a lot about the Portable Stimulus Standard (PSS), but what is it and why should you care? To put it in stark terms – because it is the first language that supports verification methodology and because the existing methodology is failing to provide the capabilities required for system-level verification.
Once a scenario has been created and executed, it will be possible to see any performance issues that may have been uncovered by the test.
This is the second of our blog series looking at the concepts contained within the Accellera Portable Stimulus Standard (PSS) (see also “Inside Portable Stimulus: Filling in the Blanks”). As a reminder, some of the material used in these blogs comes from the DVCon training session that goes over the basics of the language and how tools work. I use many of the same examples for continuity purposes, but I will present the material in a different manner.
Improve or Enable
/by Adnan HamidNew tools, languages, or methodologies can be an improvement over existing ones, or they can be enablers for something different. The recently approved Accellera Portable Stimulus Standard (PSS) can be either or both.
A lot has been written recently about how PSS can be combined with constrained random verification methodologies and that demonstrates the improvement aspect of the language.
It is to be expected that the major EDA companies are focusing on this because it gives them a good story to tell their existing verification users and an incremental sales opportunity. It also allows them to increase the value and differentiate their existing products from those of the competition, providing a strategic scaling opportunity. Unlike existing verification technologies that have been commoditized, PSS is still in its infancy and they can employ some degree of creativity in this space.
Read more
Inside Portable Stimulus: UVM Integration
/by Leigh BradyIntegrating Portable Stimulus Standard (PSS) capabilities with the Universal Verification Methodology (UVM) is not the same as an integration between two languages.
In our previous column, Aileen Honess provided a backdrop as to why a team using Universal Verification Methodology (UVM) and SystemVerilog may want to extend their methodology by adding Portable Stimulus. By incorporating a constraint solver that understands not only combinatorial constraints but also the temporal aspects of a design, it becomes possible to generate more efficient tests that target a particular verification intent.
This blog will lay out the basic strategy for such an integration. It is important to note that integrating Portable Stimulus Standard (PSS) capabilities does not remove any of the capabilities that may already be in place. Existing testbenches will still work and they will continue to provide the same coverage. PSS adds new capabilities that become useful if you are having problems reaching the desired level of coverage or if you want to make test cases that are retargetable to emulation or can be used in chip bring-up.
Read more
Interim Solutions to the Standards Gap
/by Adnan HamidThe point of standards is to bring an industry together, to avoid duplication of effort, and to reduce risks associated with adoption of technology that may lock a user into a single vendor. These are some of the reasons why Breker was glad to see the creation of the Portable Stimulus working group within Accellera and actively participated in it since its inception. We donated technology and invested more time and effort, as a percentage of company size, than any other player. We were also glad to see the release of version 1.0 of the standard at DAC in 2018 – a huge step for the industry.
But was it enough? Some standards are ratified having been developed and refined by a single company and successfully proliferated across an industry, prior to donation to a standards body. Others are designed by committee and therefore run the risk of an unproven body of work captured as a hard to change standard. Sometimes this works well, other times, less so. It is only after the fact that you know if the committee got it right. So far the Portable Stimulus Standard is being tested by a relatively large number of companies with success, but there are still missing elements for a scalable solution.
Read more
Your Invitation to Verification 3.0 Innovation Summit
/by Adnan HamidCome one, come all to the first event of what we expect will be many –– Verification 3.0 Innovation Summit –– Tuesday, March 19, from 1 p.m. until 8 p.m. at the Levi’s Stadium Team Auditorium in Santa Clara, Calif.
Meant for all of you in the chip design verification community, the event will provide advanced technical content focused on semiconductor verification innovation. It will tackle topical subjects at a deep technical level and consider the latest thinking on critical verification methodology and technologies.
The start up and smaller verification companies are a source for a large proportion of verification innovation, but getting the word out on those innovations has become harder and harder. This new event represents a single opportunity to hear the latest from all of these companies in one shot.
Read more
What Can PSS Do For You? See Breker’s Demos of Trek5’s Capabilities at DVCon
/by Adnan HamidAll of us at Breker invite https://www.dvcon.org/ attendees to step into our booth (#701) and expect to be amazed. You will see practical demonstrations of our new feature-rich Trek5 with practical examples of how the Portable Stimulus Standard can be applied to accelerate UVM coding for complex blocks and Software Driven Verification (SDV) for large SoCs.
Yes, I’m proud of Trek5 and boasting a bit. Trek5 doesn’t stop at just Portable Stimulus synthesis –– it’s a complete solution that can be deployed across the verification spectrum. We went well beyond a simple conversion of PSS models to tests that required users to perform a lot of hand codinging. Instead, we automated the process, simplifying UVM stimulus, scoreboard and coverage authoring for complex blocks and SDV, complete with portable system services, for SoCs.
Read more
Methodology, Language and Tools
/by Adnan HamidLet me start by laying the cards on the table – the Portable Stimulus Standard (PSS) is a language, not a methodology. Tools are not methodologies. Languages ensure a well-ordered transfer of information from which tools can be constructed. A methodology is a way of systematically breaking down and solving a problem in a manageable manner. Tools can enable methodologies, and, over time, tools may help to manage a methodology once it has become standardized. No standard methodologies exist today for PSS, neither are the capabilities of tools defined by the language.
Portable Stimulus is a language that provides some degree of commonality between vendors in graph-based verification technologies that are delivered in the form of tools. Those tools can be used within existing methodologies or enable new ones to be created that may not have been supported by previous tools. When vendors provide capabilities beyond those defined in the standard, it is for the user community to decide how useful they are. The good ones will get wrapped into a future version of the standard, the less useful ones will be ignored. This is how languages evolve, especially for a language defined before a de facto standard emerged.
Read more
Inside Portable Stimulus: UVM Integration Concepts
/by Aileen HonessBoth UVM and PSS solutions deploy constraint solvers to create test cases, but that is where similarities end. Thankfully, they can work together to make everyone’s life a little easier.
Read more
Inside Portable Stimulus: The Exec Block
/by Leigh BradyAtomic actions are capabilities of functional blocks, but how do these things get done? That is the responsibility of the “exec” block.
How many times have we heard the old adage “If it sounds too good to be true, it probably is”? It almost becomes second nature to dismiss new ideas when the gains are talked up but the details are hidden. This is a trap that we find ourselves in at times with the Accellera Portable Stimulus Standard (PSS). There are so many things to be excited about that we sometimes forget to talk about the more mundane aspects of the technology.
We shall fix that in this blog and get into some of the details necessary for this technology to work.
Read more
Portable Stimulus: Finding the Killer App
/by Adnan HamidFunctional verification vendors have been talking a lot about the Portable Stimulus Standard (PSS), but what is it and why should you care? To put it in stark terms – because it is the first language that supports verification methodology and because the existing methodology is failing to provide the capabilities required for system-level verification.
Read more
Inside Portable Stimulus: Concurrency and Schedules
/by Leigh BradyOnce a scenario has been created and executed, it will be possible to see any performance issues that may have been uncovered by the test.
This is the second of our blog series looking at the concepts contained within the Accellera Portable Stimulus Standard (PSS) (see also “Inside Portable Stimulus: Filling in the Blanks”). As a reminder, some of the material used in these blogs comes from the DVCon training session that goes over the basics of the language and how tools work. I use many of the same examples for continuity purposes, but I will present the material in a different manner.
Read more