SHANGHAI EDA users may not like it, but when it comes to low-power design they will probably have to speak two languages: CPF and UPF.
Since efforts have stalled to merge Common Power Format (CPF) and Unified Power Format (UPF), it's increasingly likely the industry will need to support both. "It's a headache for everybody, but we have no choice," said YC Wu, a vice president at Taiwan Semiconductor Manufacturing Co.
The CPF/UPF saga shows no sign of coming to an amicable conclusion. Last week, the IEEE approved a request to form a Working Group to develop a low-power design standard and it will use UPF as its core.
On the sidelines of this week's SEMI China conference, the group now in control of the Cadence developed CPF spec reiterated that it did not think IEEE was a good place to hash out differences. "We would never say never, but it's not a golden perfect process at IEEE," said Frank Childers, vice president of business operations at the Silicon Integration Initiative (Si2).
Childers said Si2's Low Power Consortium is still the best place to bring the two specs together. That idea has already been shot down by backers of UPF, such as Synopsys, Magma Designs, and Mentor Graphics, who believe Si2 favors CPF.
While the politics plays out, Childers said the industry should just get on with implementation. "Let's start getting products out there. We have spent too much time worrying about politics. When we talk to the users, this is the last thing they are concerned about," he said.
True, but they are wary of being saddled with the hassle of learning two specs. "The good thing is that it's at least narrowed down to two specs," said Nianfeng Li, vice president of design methodology at VeriSilicon, Inc. But the downside is that he sees another rivalry similar to VHDL versus Verilog. "Hopefully it will be easier to settle this," he added.
Technically, CPF and UPF are similar some say the resemblance is up to 90 percent. For instance, both UPF and CPF use Tcl side files with commands that allow users to do such things as establish and manage separate power domains, specify isolation and retention, set up level shifters and define power-related rules and constraints.
While today's tools use a hodgepodge of power formats and specifications, both UPF and CPF propose a common way of expressing power throughout the design flow. Many of the commands are similar as well.
"We know everybody wants one standard," said Jan Willis, senior vice president of industry alliances at Cadence Design Systems, whose Power Forward Initiative spawned CPF. Yet users, she acknowledged, are starting to realize they will probably have to translate between the two formats. "The gain of enabling the overall flow still outweighs the downside," she said, "and at least we aren't seeing a bifurcation in the approach."