You will find the usual litany of "I hate C-language hardware design" postings in John Cooley's Design Automation trip report, but there's a new twist. Some designers are actually warming to C-language design, although not necessarily SystemC or commercial C-language tools.
Cooley himself noted this new trend in the report, now available at the www.Deepchip.com Web site. "In this sea of no-thank-yous, if you read very closely you'll find a few voices speaking about how they think SystemC can work for architectural design," Cooley wrote. "As long as you're not trying to force kludgy SystemC onto the gate level, these users actually like what SystemC has to offer."
My take is a little different. Many of the designers who made favorable comments about C-language design either didn't mention SystemC or didn't much care for it. But that's not to say they don't want any C.
"To design a 10 million-gate ASIC, C-based behavioral synthesis is very important to reduce complexity," one engineer wrote. "But SystemC is very difficult for hardware designers." This engineer said his company is benchmarking Cadence's TestBuilder, an open-source C++ class library for simulation, along with tools from Japan-based Future Design Automation.
And yet, another engineer wrote that "SystemC is most interesting because it is C++, open, has wide industry support and a critical mass of users."
John Sanguinetti, founder of Forte Design Automation, chimed in to note that "SystemC has won out over my technically superior CynLib." No matter, he said, because CynLib's strength was in RTL design, which is not where C-language design will occur. Sanguinetti predicted that TestBuilder will become the "verification classes" for SystemC.
Several other engineers spoke of using C-language interfaces with simulation tools. One, however, was not impressed with Synopsys' VCS DirectC interface, saying that it's inflexible and doesn't add new features. "But it's probably a better solution than SystemC," he added.
An engineer with ARM said his company has evaluated CoWare and Synopsys C-language synthesis tools, and found that they're competing against a Verilog PLI that's "essentially free."
But the "I Hate C" crowd is still there, and ASIC designer Cliff Cummings is among the more outspoken. "The all-C-language fad is coming to a close," Cummings wrote. "Maybe some EDA company at DAC next year can hire a fat lady to sing the C-language farewell song so it will be official."