Imagination Tech Announces MIPS-based 'Warrior P-Class' CPU Core

MojoKid writes "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, a 128-bit SIMD engine (Single Instruction, Multiple Data), and Hardware virtualization (MIPS R5 can virtualize other machines in hardware). 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. 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."

Comments

MIPS never went away, but why?

[Anonymous Coward]

You can still find plenty of MIPS based embedded cpus but they're getting more and more obscure.

One of my very favorite things about the "smartphone revolution" is the proliferation of cheap ARM based SoCs. For a couple of bucks you can get a complete system in a package that runs on a couple of watts and runs circles around a high end workstation from a decade ago. (It's hard to belive 2003 was a decade ago.) And these aren't crippled micros. They're complete systems that run a real full fat operating system. Just look at the raspberry pi. Memory management On package DDR memory. Frame buffer with openGL aclleration and hardware video decoding. Amazing stuff.

Point is, arm is everywher, easy, and cheap. What's the benefit of going MIPS? (Or SH3, or PPC..)

Re:MIPS never went away, but why?

[Anonymous Coward]

It is not the problem of architecture but rather of MIPS company. I have worked on MIPS for many years and still do. MIPS architecture is not worse than ARM in any respect but MIPS company does not promote the architecture and therefore there are no inexpensive boards available. PIC32 is MIPS architecture but without the MMU. I found that when implemented correctly performance of MIPS is on par with ARM per MHz but ARM can clock higher in most common implementations. There is a perception of MIPS being slower or more power hungry. In my experience this is not the case. I also like architecture itself. It is very clean and with modern additions it has all of the tricks that ARM has.
If MIPS company would promote its chips the same way as ARM does it would be just as popular with the hobby crowd. MIPS is used in many devices - cars, settop boxes, routers, etc. It is just not popular in the DYI community due to absence of cheap hardware.

And thusly PowerVR admits defeat (again)

[Anonymous Coward]

We've seen this before. Imagination blown to bits in the PC 3D-accelerator marketplace, and forced to withdraw with its tail between its legs. Now Imagination seems on the edge of admitting defeat in the hight-end ARM GPU market, and vanishing into this fantasy market of competing with ARM using its MIPS core.

The problem Imagination has is that there are too many players in the ARM GPU space. ARM itself provides MALI cores, both cheap and nasty ones for all bottom end ARM SoC devices, and high-end ones for GPGPU applications. Qualcomm, of course, has the Adreno (via a long ago purchase of ATI's mobile GPU division), and Qualcomm is the current 'Intel' of the ARM market. Nvidia and AMD are both providing their AAA gaming/GPGPU cores to 2014 ARM parts, moving the ARM high-end beyond anything Imagination can dream of matching.

At the moment, PowerVR is 3DFX (at the height of its success) strong in the ARM market, but faces the same problems that brought 3DFX's fortunes crashing down. PowerVR is currently used by Apple in all its non-x86 products. The important Chinese ARM chip companies are also starting to use PowerVR as well. PowerVR is in a golden age, but struggles to see a sunny future.

Soon, basic OpenGL ES2.0 functionality on ARM SoC parts will return almost worthless to the GPU IP companies. Good enough acceleration for everything but proper games (which have yet to have an important impact on ARM devices) is in a hardware race-to-the-bottom, with too many excellent competing designs. This mirrors the end of value in the PC 2D video space, after years of excellent profit for companies like Hercules, S3 and Number-nine.

No-one survived against AMD/ATI and Nvidia in the AAA-gaming GPU space. AMD won the Wii U, PS4 and Xbone. The existing handhelds are the last bastion of non-Nvidia, non-AMD GPU designs for proper gaming. AMD and Nvidia have worked hard recently to scale their desktop solutions into the high-end of the ARM mobile space, and intend to provide no-compromise gaming GPUs for this market.

The last time Imagination went up against Nvidia and AMD, it was a bloodbath, and both companies are far better and far more ruthless today.

So, now Imagination is biting the hand that feeds it- namely ARM. You can imagine how this will end. And Imagination is throwing their hat into a ring where Intel fights (with ZERO success). If Intel cannot beat ARM (and it most certainly cannot), Intel can take some pointless satisfaction in pummelling Imagination's MIPS ambition into non-existence. Wherever Imagination takes MIPS, it will find Intel there first with 'Quark' and other assorted Intel rubbish that Intel has the money to persuade companies to use ahead of anything but ARM.

MIPS is a better choice anyway

[AaronW]

MIPS provides a much cleaner upgrade path going forward than ARM. MIPS64 is a very clean extension to MIPS32. All of the MIPS32 instructions behave the same except that they are sign extended to 64-bit. 64-bit ARM on the other hand has almost nothing in common with ARM32. The instruction encoding is totally different. The register definitions are also completely different. A lot of the things that made ARM ARM are gone such as conditional execution.

I have spent many years working with MIPS and the last three working for a 64-bit multi-core MIPS manufacturer. MIPS also allows for clean extensions to the instruction set by various vendors, something ARM does not allow. For example, my employer has added a lot of instructions using coprocessor 2 (COP2) to add encryption, hashing, CRCs and more without breaking standard MIPS compatibility since COP2 is typically reserved for vendor extensions.

MIPS page tables are also interesting. They are entirely managed by software, allowing the operating system to use whatever format they want for them. While some vendors have added hardware walkers they typically don't make much difference in performance.

MIPS32 is fairly old and many implementations don't provide cache coherency which is a pain in the butt and impacts performance but the ones I deal with (Cavium's OCTEON processors) are fully cache coherent.

As for doing encryption in the instruction set it allows full acceleration in user space without needing to deal with descriptors or DMA or userkernel transitions.

Perhaps the only thing I would get rid of is the branch delay slot. It no longer really buys anything. The MIPS tools are much more mature than ARM, especially for 64-bit support. There are 32 general purpose registers with register 0 always being 0.

With ARM64 most of the interesting ARM features are gone and in fact it looks a lot more like MIPS except that the instruction decoding is a lot more complicated. MIPS hasn't been standing still either. Extensions have been added for things like virtualization, 16-bit instructions (like Thumb) which usually don't buy you much and some multimedia extensions.

I periodically work on MIPS assembly language with some of the bootloader stuff I do. All I can say is it's a joy to work with compared to X86 and is quite elegant. It's nice when I can have just a couple dozen lines of assembly language put a stack in cache memory and go straight to 64-bit C code. At this point it's quite hard for me to beat recent versions of GCC when it comes to optimizing code.

I don't know why they're limiting their Warrior P-Class CPU core to 32-bits though. Moving to 64-bit MIPS is not very difficult. Personally I'd love to see 32-bit MIPS go away and just do 64-bit MIPS and use either the N32 or N64 ABI. N32 runs in 64-bit mode but with 32-bit addressing so you get all the advantages of 32-bit pointers and 64-bit registers.

My employer makes MIPS processors with up to 32 cores and soon will have 48 cores and fully support Linux.