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IBM Goes Open Source on Key Microprocessor

Broader applications to come from easier access to its Power architecture

3 min read

30 April 2004--In the battle between the free, open-source operating system Linux and proprietary operating systems, IBM Corp. has emerged as Linux's champion. Now, seeming to take a lesson from its experience with open-source software, the company has decided to make its premier processor architecture, dubbed Power and used as the brains inside many IBM servers and supercomputers as well as Apple Computer Inc.'s Macintosh PCs, into an open-source technology.

On 31 March, the company announced that product developers will be able to license the Power architecture at little or no charge and customize it for their own products. Developers of a chip to be based on the Power architecture will be able to build it any way they want--using different generations of silicon technology or even materials other than silicon. They will also be able to add media and input/output drivers or other peripheral circuitry needed for their applications. In short, they will be free to do anything they choose, as long as the device can still run Power-based software.

IBM hopes that by opening up Power to other developers, the platform will spread to a much wider range of products, from handheld devices to networking equipment, than it can develop on its own. "We are seeing that Power has applications in many areas," says Lisa Su, vice president, technology development and alliances, for IBM's Systems and Technology Group. "And there's no way that IBM or even our close partners are going to think of all the uses for it."

As microprocessor business models go, the new Power open standard is unlike any other. MIPS Technologies Inc. in Mountain View, Calif., and ARM Ltd. in Cambridge, England, also license microprocessor cores. But their licensees have to pay fees up front in order to access the architecture and royalties from the sale of products containing their microprocessor cores. In contrast says Shane Rau, senior research analyst at IDC, Framingham, Mass., the approach that most closely resembles IBM's is Linux's. The Power standard is freeware made from silicon rather than software code.

The one stipulation that IBM has is that the developers not change the set of instructions that programmers use to write their software. This instruction set is the foundation of the architecture; and ensuring that it remains unchanged will protect the architecture from fragmenting into many incompatible versions. There may come a time when changes to the architecture become inevitable. To deal with that concern, IBM is exploring the establishment of an independent governing board that would oversee the processor's instruction set, make the needed changes, and keep the architecture from fragmenting. At this point, IBM is vague on exactly how such a governing board would work. "We are still working out the details," says IBM's Su.

In the past, IBM licensed the Power architecture to only a few of its best and biggest partners. If other developers wanted access to the technology, they had to go through the company's ASIC design and foundry business. "Power was something we used in our high-end servers and sold to equipment manufacturers, but our priority was never to promote it as an open architecture," explains Su.

But IBM managers, seeing an opportunity, had a change of heart. In addition to the more open licensing policy, IBM has expanded licensees' design and manufacturing alternatives, so users won't have to come to IBM for either the design or manufacture of their Power-based ICs. Two foundries, Chartered Semiconductor Manufacturing Ltd., in Singapore, and Taiwan Semiconductor Manufacturing Company Ltd., in Hsinshu, now have the Power manufacturing technology and the design libraries that will allow them to manufacture Power-based ICs. IBM is also helping suppliers of chip-design software to support Power and has already signed agreements with two leading California design automation companies, Synopsys Inc., in Mountain View, and Cadence Design Systems Inc., in San Jose.

Altruistic as IBM's architecture giveaway may sound, the company could profit from it. Very few of the companies that take up a license and start designing around the architecture, are likely to have their own fabs, notes Rau. So they are going to need to go to a company that can fabricate their design. They could choose to go to Chartered or TSMC. But they may assume that since IBM has the best understanding of the architecture, it can do the best manufacturing job. "They have a lot of Power-related intellectual property they can sell," says Rau, "and they have design services that help their customers integrate the microprocessor cores and the peripheral intellectual property together. So IBM would be competing with the other fabs for the business, but it would have a leg up on them." That might be a needed boost for IBM's chip-making business which lost US $150 million last quarter due in part to yield problems at its East Fish Kills, N.Y., fab.

And the more systems built around Power, the more chance IBM will see some financial benefit. "Think of a digital device and probably IBM has hopes that Power can penetrate it," says Rau.

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