San Jose, Calif. Intel Corp. today will bring standards-based PC multimedia, power-management and security capabilities to cell phones, with the rollout of an Xscale-based applications processor that takes a notably different path from such established cell phone chip makers as ARM Ltd. and Texas Instruments Inc.
Intel's PXA27X, also known as Bulverde, employs a functional equivalent of the Pentium's 43 multimedia instructions called Wireless MMX, along with a cell phone version of Intel's Trusted Computing Module, an emerging desktop PC security standard. The chip also includes power-management technology borrowed from Intel's notebook CPUs as well as a proprietary camera interface and a baseband interface Intel will try to establish as a cell phone standard.
A senior member of the technical staff at Texas Instruments asserted that his company will not support Wireless MMX but will instead stick to existing and pending multimedia enhancements for the base ARM architecture.
"We believe in open architectures and instruction sets. We have decided not to go with any proprietary instruction sets," said the staffer, Avner Goren, who manages the company's mobile-systems marketing group.
TI will use the ARM11 version 6 instruction set in its Omap-2 processors, set to ship later this year.
ARM is preparing to roll out the first of a series of multimedia enhancements for its architecture, said David Steers, a marketing director for that company. "We have active programs in this area because we recognize the applications processor is taking on more of a multimedia role," said Steers. "We will have some multimedia technology in the next couple months to help in certain tasks.
"This is only one part of a multimedia strategy we have under very intensive study," Steers said.
The ARM11 already supports some single-instruction multiple-data commands roughly similar to parts of MMX. "Intel's Bulverde brings a level on top of that," Steers said. He would not elaborate on ARM's plans beyond the promised extensions.
Intel wireless-marketing manager David Rogers said more than 30 application developers are writing cell phone apps using Wireless MMX. Most will use standard C-language calls that tap a set of optimized assembly language graphics primitives developed by Intel, he said.
Intel claims Wireless MMX will let an entry-level 312-MHz Bulverde handle tasks that would require a 520-MHz ARM processor. In terms of power savings, a Bulverde chip can handle 15.5 hours of MP3 music playback or 1.3 hours of videoconferencing, compared with 10.9 hours of music or one hour of videoconferencing on an Xscale processor without Wireless MMX.
Some of the power savings on Bulverde come from its use of SpeedStep, a technique used in Pentium notebooks to scale CPU voltage and frequency to the needs of an application. Intel is also supplying a software module that will monitor system performance and CPU utilization to create power-management policies automatically.
Separately, Intel will equip select Bulverde models with a hardware security block based on the Trusted Computing Modules defined for desktop PCs by the Trusted Computing Group (www.trustedcomputinggroup.org). The modules handle hardware-accelerated cryptography for securing digital keys stored in 32 kbytes of on-chip memory.
The modules can handle virtual private network and Secure Sockets Layer tasks and have on-board ROM for implementing a secure boot process. Intel will also supply an application programming interface and a library of assembly language cryptography primitives.
ARM announced its own security architecture, TrustZone, last October and will make it available to licensees in the ARM1176 core, due to be released by the end of June.
The Trusted Computing Group is developing a cell phone variant of its PC module spec. ARM, Intel and Nokia are part of that effort, but it is not clear when the variant will be finished. By upgrading its crypto library in the future, Intel will be able to support the TCG specification when the spec is released without requiring developers to write new applications code, said Rogers.
Bulverde is Intel's first applications processor equipped with its Mobile Scalable Link. MSL is a baseband interface providing data rates up to 416 Mbits/second over a 1-, 2- or 4-bit-wide,1.8-volt multiplexed and buffered I/O channel.
"We are proposing this as a standard to MIPI," said Intel's Rogers, referring to the recently formed Mobile Industry Processor Interface Alliance (www.mipi.org), an ad hoc standards group.
Nokia and Texas Instruments are expected to drive much of the standards work for such an interface within MIPI. But it is not clear when any new standards might emerge from the alliance, which now has about 39 members.
Bulverde also includes QuickCapture, a proprietary interface geared for charge-coupled devices and CMOS image sensors. It supports a variety of imagers including the Omnivision 9640, Agilent 2650 and Philips UPA 1012. It handles 640 x 480 resolutions at up to 15 frames per second and 320 x 240 resolutions at 30 frames/s.
Many companies have developed their own interfaces, and MIPI is expected to address the issue in coming months. The standards group has already defined a legacy interface called the Camera Serial Interface 1.0, running at up to 216 Mbit/s, that TI supports in its Omap-2 family.
Analysts generally praised Intel's efforts to craft a more muscular multimedia processor for mobile systems. "Finally Intel is coming out with what the market demands for an applications processor," said Will Strauss, principal of market watcher Forward Concepts (Tempe, Ariz.). "They found that to handle MPEG encode, the Xscale requires 500 MHz and eats a lot of battery life. Wireless MMX helps them lower the clock rate and battery drain. It's what they should have produced two years ago."
Steers of ARM also praised the multimedia advancements in Bulverde (whose Xscale foundation is based on the ARM architecture). "This is a great innovation for Intel, which is also great for us. But we are not going to fall behind in the multimedia road map race," he said.
Rather than use a large general-purpose processor such as Xscale, Goren said, TI uses a variety of optimized processing elements running in parallel in Omap-2. Having separate engines for DSP, 3-D graphics, imaging and other tasks is the better route to saving power and providing a good user experience, Goren said. The Omap-2 processes 2 million polygons/s, handles H.264 video, supports up to 6-Mpixel imagers and provides Java hardware acceleration. Intel's Bulverde requires a separate 2700G multimedia accelerator, which handles 994,000 polygons/s and does not support H.264. Bulverde handles imaging sensors up to 4 Mpixels and does not have special Java acceleration hardware.
But Intel's Rogers said a general-purpose processor provides a simpler route to handling power management. He noted that Bulverde is shipping in volume now and will appear in handheld systems this month. The TI parts may not ship until next year. By that time Intel could have versions of Xscale that integrate the multimedia accelerator, Rogers said.
Intel will provide many versions of Bulverde, including discrete versions; chips incorporating the security module; and stacked packages, with up to 64 Mbytes of Intel's StrataFlash and 32 Mbytes of SDRAM. Speeds will range from 312 to 624 MHz, with volume pricing for entry-level parts starting at $32.
Intel is new to the cellular sector. Thus far among top-tier OEMs, Samsung has announced three phones and Motorola has launched one phone using an Xscale applications processor.