By Ron Collett

In December, we were honored to participate in a Design & Reuse panel in Grenoble, France, titled “IP Reuse vs. IP Leverage: What’s the difference and what are the issues?”

Andrea Fortunato, our European director of professional services, represented us and gave an overview of the particular challenges that design reuse brings. He blogged about it right after the panel (Design Reuse: It’s Harder Than it Looks).

Our friends at D&R have just posted an audio Webinar of that panel. It’s definitely worth a listen if you’re designing with cores and trying to take advantage of reusability.

Have you had design reuse challenges recently? If so, feel free to comment on this post to let us know what they were and how you overcame them. Improving productivity in the semiconductor industry is a communal effort!

By Andrea Fortunato

How best can we leverage IP in an era of relentlessly increasing design complexity? That was the question on the table at this week’s IP-ESC 2009 conference here in Grenoble. I was honored to sit on a panel with Jasper Design Automation CEO Kathryn Kranen and Olivier Haller, who manages the design verification team in the Functional Verification Group at STMicroelectronics.

Our CEO, Ron Collett, described the IP situation in a post last week as the design reuse paradox, in that re-using IP is harder than it looks. In fact, there are dangerous consequences for any project leaders who think it’ll be a cakewalk.

During the panel this week, I made the point that most teams underestimate the complexity that the reused IP— adapting a particular block to a new context or adding particular features and then validating it—will add to their project.

This miscalculation is particularly dangerous for derivative designs, whereby the reuse level of their blocks is expected to be significantly high. Executive management loves derivative designs because they’re operating under the assumption that most of the work has already been done on the original design and the derivatives will be easier and deliver higher margin.

Truth and Consequences

But the reality is teams use ever-more IP blocks (including complete functions and sub-systems) on a chip. Underestimating the complexity at the block level is compounded at the chip level, and this creates unrealistic performance expectations from the development teams.

What happens?

• The project schedule slips

• Team members have to be pulled from other on-going projects to bring the project to closure, throwing the predictability of schedule in those other projects into doubt.

What are the consequences?

• The overall market window is reduced and peak time window for product introduction is reduced

• Development cost increases, exploding the project’s initial budget. ROI window is reduced

• Both time to market and ROI are affected!

The ripple effect of underestimating the effort needed to develop, integrate and validate the IP is far-reaching: The resource disruptions delay key projects because resources already involved on other developments are pulled in to salvage one development. The ripples turn into waves that slam the schedule and cause budget over-runs for the whole the project pipeline.

Remediation

There are two major ways to address this situation.

First, fact-based planning at the project’s outset helps avoid this turmoil. By measuring and quantifying project complexity and schedule risk, team leaders can see the gap that might result between their initial effort assumptions and the effort they’ll actually need based on the data. This helps them make fact-backed what-if staffing simulations and create aggressive—yet achievable—schedules.

Second, pick your design battles carefully. Analyzing projects in our extensive industry database, we see that best-in-class design teams show a lower amount of reuse than the average of their segment. This means that those best-in-class projects re-use IP where it is most appropriate to do so—for example in standard functions that don’t bring value add and real differentiation to the final product. But, best-in-class companies leverage their own innovation and fully engage their engineering resources in situations where the performances of specific functions are the key differentiating factors from the competition.

In the end, the key challenge for an IP user is :”Keep the ROI in the Product Development!”

(Andrea Fortunato is director of professional services for Numetrics, based in Grenoble).

By Ron Collett

The concept seems simple: The more ip blocks you re-use in an IC or system design, the faster and more productively you’ll get your design done. The ITRS roadmap began identifying the benefits as long ago as 1997, showing the industry could reasonably expect 56,000 gates per designer per year when using large ip blocks (75,000-1 million gates). By 2007 that figure was up to 600,000 gates per designer per year, a tenfold increase.

There’s no doubt design reuse is here to stay. In 2007, a third of all logic was reused design blocks. That’s expected to rise to nearly 50 percent by 2015, according to the ITRS.

The numbers and the theory behind it are encouraging, but reality is much different. Making 30 percent of your design from reused IP blocks doesn’t mean you’re going to be 30 percent more productive at the end of the project. That’s because IC design teams tend to underestimate the work needed to implement the reused IP. This can cause project delays and missed market opportunities.

The challenge is that it’s very difficult to estimate design complexity, especially the impact of reuse. IC design schedules can falter because of the inability to estimate the impact of IP modifications on project effort.

Even a small percentage of reuse can add outsized effort to a development project. For example, if you add one new block of 600,000 gates to a 6 million-gate design, you’re adding 10 percent to the IC but increasing the effort required on the project by 24 percent. Adding 10 percent new circuitry to all blocks in that 6 million-gate design—with 90 percent of each block being re-used—doubles the effort required on the project, even though it increases the IC size by just 10 percent to 6.6 million gates.

This issue will be part of a larger discussion Dec. 1 at IP-ESC 2009 in Grenoble. We were invited to sit on a panel—“IP Reuse vs. IP Leverage: What’s the difference, and what are the issues?”—with Kathryn Kranen, CEO of Jasper Design Automation, and Olivier Haller, who manages the design verification team in the Functional Verification Group at STMicroelectronics. Our director of professional services, Andrea Fortunato, will represent Numetrics.

This is a well-timed panel in my opinion because re-use is an issue that transcends the industry and is crucial for its future. And how we go about optimizing design re-use is crucial to manage today.