Imagination Technologies has announced the first CPU
based on its new version of the MIPS
architecture. The new P5600 chip (codenamed Warrior) is a 32-bit CPU based on the MIPS Series 5 architecture and is designed to challenge companies like ARM in the embedded and mobile markets. Major features of the new chip include:
- Support for 40-bit memory extensions, or up to 1TB of RAM rather than the typical 4GB limit associated with 32-bit processors. It's worth noting that there's typically a significant performance hit associated with this kind of work-around for memory addressing in 32-bit chips.
- A 128-bit SIMD engine (Single Instruction, Multiple Data). Companies like ARM, Intel, and AMD use various SIMD instruction sets (Neon for ARM, SSE, AVX for the x86 companies) to boost performance in vector and scalar operations. Adapting an SIMD engine of its own will help MIPS hit higher performance targets.
- Hardware virtualization: MIPS R5 can virtualize other machines in hardware. This is designed to serve as both an enterprise and a consumer feature. ARM's blog describes it thusly: "For consumer devices, this enables increased security between one OS on which users are allowed to add their own applications, and a secondary mission-critical OS with which users can not tamper."
The P5600 core is being touted as supporting up to six cores in a cache-coherent link, most likely similar to ARM's CCI-400, which links processors, L2 caches, and other components of the SoC. According to IT, the chip is capable of executing 3.5 DMIPs/MHz in CoreMark, which theoretically puts the P5600 on par with the Cortex-A15
, which is also rated at 3.5DMIPS/MHz. Whether this is actually true in real-world code is something we can't confirm at this point in time.
Imagination Technologies is claiming a wide range of clock speeds (1GHz - 2GHz) and states that the MIPS core is up to 30% smaller than "competing silicon." This is the kind of statement that tends to make us leery of leaning too hard on the DMIPS rating as a measure of performance. One of the fundamental truths of semiconductor technology is that performance costs die size. The Cortex-A15, for example, is far more powerful than the Cortex-A9 -- and significantly larger.
This new core is the first of a family, with later 64-bit chips to follow. The 64-bit warrior chips, when they do launch, will be fully backwards compatible with 32-bit software, much like the 64-bit implementations of ARM and Intel/AMD.
New Life For MIPS?
Will this new core kick off a new chapter in MIPS' long history? It's difficult to say. Once upon a time (read: the early 1990s), MIPS was actually the high performance graphics workstation architecture of choice. Both the PlayStation and PS2 used MIPS-based technology as well, but little by little, the CPU faded into the background. Today, the architecture is typically used in routers, cable modems, and smartcards. It's also the basis for China's Loongson
microprocessor family and will be integrated into the Dawning 6000, a Chinese supercomputer under development.
The P5600's high performance target and the decision to integrate an SIMD engine with hardware virtualization capabilities suggests that Imagination Technologies is hungry to take on ARM in its own backyard. This may partly be a defensive play -- for years, IT and ARM have been close partners, with ARM cores typically launching alongside PowerVR GPUs. While the two companies remain close partners, the fact that ARM has ramped up its own Mali GPU family is a threat to Imagination Technologies' own dominance in the mobile graphics space. Then, too, there's the fact that an increasing number of SoC vendors incorporate their own native GPU technology -- ARM has Mali, Nvidia's Tegra is built on GeForce, and Qualcomm
. Even Intel's upcoming phone processors will use an iteration of its own graphics tech.
Rather than see its products marginalized or confined to Exynos
products (Samsung, to date, has not launched its own GPU), Imagination is making a play for an independent CPU. Whether it can scale the MIPS chip and win sufficient designs to catch the eyes of phone manufacturers remains to be seen, but this is an important launch for the company.