Cadence Industry Insight: “Virtual Platforms Unite HW and SW”

opinionAnother Cadence guest blog entry, about the overall impact of virtual platforms on the interaction between hardware and software designers. Essentially, virtual platforms are a great tool to make software and hardware people talk to each other more, since it provides a common basis for understanding.

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Is Cycle Accuracy a bad Idea?

In a funny coincidence, I published an article at about the need for cycle-accurate models for virtual platforms on the same day that ARM announced that they were selling their cycle-accurate simulators and associated tool chain to Carbon Technology. That makes one wonder where cycle-accuracy is going, or whether it is a valid idea at all… is ARM right or am I right, or are we both right since we are talking about different things?

Let’s look at this in more detail.

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SCDSource Article: Combining Fast and Detailed Models

I have another opinion piece published over at The title, “Why virtual platforms need cycle-accurate models“, was their creation, not mine, and I think it is a little bit off the main message of the piece.The follow-up discussion is also fairly interesting.

The key thing that I want to get across is that we need virtual platforms where we can spend most of our time executing in a fast, not-very-detailed mode to get the software somewhere interesting. Once we get to the interesting spot, we can then switch to more detailed models to get detailed information about the software behavior and especially its low-level timing. Getting to that point in detailed mode is impossible since it would take too much time.

This is something that computer architecture researchers have been doing for a very long time, just look at how toolsets like SimpleScalar and Simics with the Wisconsin GEMS system use fast mode for “positioning” and more detailed execution for “measurement”. It is also what is now commercial with the Simics Freescale QorIQ P4080 Hybrid virtual platform. Tensilica also have the ability to switch mode in their toolchain.

See an upcoming post for more on how to get at the cycle-accurate models – this was just to point out that that the article is there, for symmetry with previous posts about my articles popping up in places.

SCDSource Article on Virtutech DML

SCD Source LogoI have an article at, about how virtual platform creation needs to become more efficient. And the Virtutech current solution to that issue, DML, Device Modeling Language. There is no need to repeat the contents here, just head over to to read it! I really think that DML has something to contribute in the world of virtual platforms. We need to find ways to be more efficient about how to create models, and that means creating a better programming language.

So what is SCDSource? Is is a quite good news and analysis site about the electronics industry, EDA, virtual platforms, and other themes close to my heart. SCDSource was started in October 2007, and have produced a series of good and interesting articles since. They tend to actually write articles and not just repeat press releases, and to report form interesting panels at events like DATE, ESC, and Multicore Expo.