Electronic Design: How would you assess the status of design reuse today?
John Swanson: Clearly, there's still work to do. But there's growing industry adoption of on-chip buses like the Open Core Protocol (OCP) and ARM's AMBA, among others. Standards efforts like those of the SPIRIT Consortium are making IP reuse easier for both the IP itself and for the tools.
Ian Mackintosh: We're seeing improving industry collaboration. For example, OCP-IP is starting new initiatives on fronts such as debug and networkon-chip (NoC) benchmarking. From the SoC design implementation perspective, what works for designers is using large, mature IP libraries. By doing so, they're protecting themselves from vulnerable aspects of the design process.
ED: What are OCP-IP's new initiatives in debug and NoC benchmarking?
IM: For debug, we've published a white paper on how the OCP interface allows for a debug socket that permits the interoperability of otherwise disaggregated hardware, software, and inter-SoC debugging. A specification is in development now, and the first
rough drafts are in review. The white paper is available free at www.ocpip.org.
In NoC benchmarking, it's not just about connecting IP blocks and how the individual blocks perform. Rather, it's a system-level focus. Comparing various approaches to implementing a NoC is critical. We've published a benchmarking white paper and have had papers, seminars, and panels at conferences this spring.
ED: What's not working so well in design reuse? IM: I consistently hear that IP quality is still a problem. Just because you get one good piece from a vendor doesn't mean you'll get a second good one. It's causing changes in purchasing behavior in that large organizations are tending to select a small number of IP providers. Last but not least is that there's no uniform supply of IP. There's no conformance to uniform packaging, testing, or delivery schemes of content.
JS: There are issues with IP quality. That's why you've seen fewer new IP companies, except for very focused ones. Developing quality IP is a very significant investment. IP delivery is one of the key challenges for SPIRIT. I'm chairman of SPIRIT's Verification Working Group, and we haven't solved all the existing
problems. But we've made progress in that people can take IP from multiple vendors and bring it into their design environment much easier than they could a couple of years ago.
IM: All of these quality issues will improve as standards evolve. VSIA's QIP Metric has made a difference, and this goes back to industry collaboration. We'll see broader adoption of standards from existing bodies, as well as new organizations and new interorganizational and inter-company collaborations. In the case of OCP-IP, for example, we recently announced our collaboration with Synopsys to make its DesignWare verification IP available to our members. We've had collaborations or donations in many areas, including transaction-level modeling, PSL properties, and SystemC assertions. On the technology front, improved ESL products and higher-level design schemes, feeding down to a more productive implementation and verification flow, will drive reuse productivity. On the quality front, VSIA is doing very important work. We need higher conformance on what people should expect to get and have quality metrics by which to measure it.