Sun, allies broaden open-source chip push

Sun has two early takers--Simply RISC, with operations in England and Italy, and Polaris Micro in China. Both are designing variations of OpenSparc S1, the open-source version of Sun's UltraSparc T1 Niagara processor.

But those companies and others will have more to work with in the future.

"It is our goal of eventually open-sourcing these Sparc processor designs," said David Yen, head of Sun's newly re-created microelectronics group, speaking of Niagara 2 and the Neptune networking chip derived from it.

Sun has begun arguably the most aggressive transformation of its business from proprietary products to the polar opposite, open source. Most of its software is or soon will be open source--an increasingly common practice in the computing industry--but Sun is unusual in releasing hardware designs as well.

As with its open-source software plans, the OpenSparc project is a bid for relevance first and revenue later.

The outside Sparc activity provides "a real example that OpenSparc is more than a publicity stunt," said Illuminata analyst Gordon Haff. "Although, as with Sun's other open-source activities, resultant revenue to Sun remains more a matter of faith than scientific fact."

Sun says it believes the open-source move will mean financial gain. "Through exposure and familiarity, we reduce the entry barrier--even if just mentally--for people to adopt Sparc processors in various places, including our system platform products," Yen said.

Sun wants to give Sparc a higher profile. The processors were the server brains of choice during the dot-com frenzy of the late 1990s, but they declined in importance as the chips lagged the competition's performance, delays hit new models and the dot-com bubble pulled the rug out from under Sun's server business.

The Santa Clara, Calif.-based company has stabilized its server business somewhat, partly because its UltraSparc IV+ servers did much better than expected, partly because Sun belatedly welcomed x86 processors such as Intel's Xeon and Advanced Micro Devices' Opteron into its server line, and partly because Niagara servers have made modest gains--for example, sales of $125 million in each of the last two quarters.

Although Sun has hedged its bets with x86, it's still pushing Sparc hard. Niagara 2 is due soon in single-processor machines and in dual-processor models in the first half of 2008. Its high-end cousin, "Rock," is due to ship in servers in the second half of 2008. Sun last week announced that its Solaris operating system now has booted on a Rock prototype server, a significant accomplishment that indicates not just that the chip works reasonably well, but that the rest of the system does, as well.

Selling derivatives
OpenSparc has gained Sun some allies. China-based Polaris Micro chose to use the chip because it's open source, Chief Executive Naxin Zhang said. It's using its OpenSparc variant, to be built by a local chip foundry, in a system board it will sell to customers in the telecommunications and data-storage businesses.

"I can view and modify the source code. It also comes with verification, architecture simulation and other tools," Zhang said. "We truly believe OpenSparc will blossom in the future because it is open."

That openness makes it possible, for example, to build a version that plugs into the "Torrenza" chip socket used by Advanced Micro Devices. One Chinese telecommunications company is interested in that possibility, Zhang said.

Simply RISC, too, was drawn by the open-source license. Sun chose the General Public License (GPL), which also governs the Linux kernel and thousands of other software projects.

"We believe in the strength that comes from the use of the GPL license," said Fabrizio Fazzino, one of Simply RISC's two main designers. "There are many success stories in the world of software, and we believe that it is time for something similar to happen in the hardware world."

The choice of the GPL has interesting implications. The license permits anyone to change designs--but if an organization distributes products based on the modified design, it must publish those changes.

The GPL serves as a convenient check on rivals who might want to profit from Sun's multicore investments by wrapping their own interface on a Sun Niagara core, Yen said.

"With the GPL, if our direct competition--IBM, Intel and AMD--wants to copy what we have done in high thread count per core, they will have to put (their changes) back. That will potentially be a barrier to just copying what we've got," Yen said. Those rivals might be leery of revealing not just their own designs, but also might be forbidden from revealing third-party intellectual property, he said.

Cores and threads
Sun's Niagara chip is the industry's most aggressive example to date of general-purpose multicore chips--those with multiple processing engines on each slice of silicon, as opposed to the comparatively old days when each chip had only a single processor engine. Niagara has eight cores, and each core can process four instruction sequences called threads.

Niagara 2 still has eight cores, but each can handle eight threads, and the chip has better number-crunching abilities as well as built-in encryption, input-output control and 10-gigabit-per-second networking. Niagara 2 servers are due to ship in the third quarter of 2007, Sun Chief Executive Jonathan Schwartz said in April.

Sun recognizes that this multicore, multithreaded approach isn't easy for some necessary partners in the software industry to digest. Trying to encourage their support is another reason Sun opted for the OpenSparc project.

"We strongly believe this multicore, multithreaded direction is the way to go, both for efficiency in computing and efficiency in power consumption," Yen said. "But this cannot be done alone by hardware processor vendors. It requires the software community, all the way from system software to application software, to adapt and participate," he said. "By open-sourcing OpenSparc S1, it's also sending strong signals urging the IT community to go in that direction."

But it's notable that the two companies so far working on open-source derivatives aren't as bold. Both Polaris Micro and Simply RISC have designs with a single four-thread core.

There are complications to making Niagara 2 an open-source project. One of them is export control, because the U.S. government imposes restrictions on encryption technology.

"Suppose today I want to publish an implementation of elliptic curve cryptography algorithm. I'm not sure the government will allow us to do that," Yen said. "There are more things we have to work out, clarify, maybe get certain permissions."

Programmable chips
Making a chip design an open-source project is a very different beast compared with open-source software projects.

It's easy to get a computer, download some software source code, and start programming away. But when it comes to hardware design, fewer people have expertise, and a chip foundry isn't likely to be interested in allocating fab capacity to build a handful of some amateur's experimental processors.

But for would-be open-source chip designers, there's another way: field-programmable gate arrays, or FPGAs. These programmable chips are blank slates from companies such as Xilinx onto which designers can load whatever hardware logic is desired.

To that end, Sun has released a version of OpenSparc that runs on an FPGA, said Shrenik Mehta, Sun's senior director of the OpenSparc program. The design has just a single core with a single thread so students can figure out ways to beef it up, he said.

"It works like a building block, so students can experiment in the lab or course work to do different designs with one core and two threads, two cores, etc.," Mehta said.

Indeed, that's just what the University of California at Santa Cruz is doing in one of its courses. Sun established a center of excellence at the university to try to foster collaboration, and a U.C. Santa Cruz assistant professor, Jose Renau, is a member of the OpenSparc community governance board.

Though Sun is pleased with the open-source chip effort so far, including 4,700 downloads of the design, the company recognizes that progress so far is very early.

"Though the publicity is getting broadened," Yen said, "most people are still digesting and trying to understand what we are offering."