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AMD Patent Shows Off Potential CPU With Integrated FPGA

Ryzen 7 5800X
(Image credit: Tom's Hardware)

AMD has been doing wonders in the CPU industry, with its well-received and high performing Zen 2 and Zen 3 based processors, but now it seems AMD wants to improve performance not just through faster cores, but through the use of FPGAs. Just a few days ago, AMD filed a patent for integrating FPGAs into a CPU, which would allow the processor to run custom instruction sets to extend the its capabilities. As a side note, this patent was made just a few months after AMD's acquisition of Xilinx, a company dedicated to making FPGAs.

FPGAs, or Field Programmable Gate Arrays, are simple yet powerful devices that can run specific instruction sets very quickly. This is different from a standard x86 CPU core that's designed to run a near-infinite variety of instruction sequences, albeit sometimes slowly. If there's a specific task (graphics, physics, encryption, etc.) that's used regularly, it might be beneficial to create a custom instruction on an FPGA that will process the code much more quickly. Plus, FPGAs aren't limited to a single instruction set; they can be re-programmed to run another instruction set if necessary.

This seems to be what AMD is going for, and AMD's implementation would allow the FPGA unit to share registers with the CPU itself. Simply put, this allows the CPU to very quickly offload instructions to the FPGA unit when necessary. We don't know what specific tasks AMD is looking at, but presumably anything currently using dedicated FPGAs could see support. We also don't know where this FPGA (or FPGAs) would be located. If we're talking about a Zen 2 or Zen 3 based design, the FPGA could be installed on its own separate die (chiplet) connected via the infinity fabric. Alternatively, it could be integrated directly onto the CPU chiplet, sharing a die with the cores. This would be the most optimal setup as far as performance goes, but it would require new compute chiplets.

AMD has yet to announce any new processors that take advantage of an FPGA unit. Still, this technology could be very beneficial in the future for improving processor performance as CPU architectures continue to become more difficult to shrink.

  • tommo1982
    FPGA's are used in chip design, are they not? I don't recall them being fast. Reprogrammed to see how a chip might behave, but it's not fast.
    Reply
  • everettfsargent
    tommo1982 said:
    FPGA's are used in chip design, are they not? I don't recall them being fast. Reprogrammed to see how a chip might behave, but it's not fast.
    https://en.wikipedia.org/wiki/Field-programmable_gate_array
    If you CISC/RISC complex algorithm runs slower than on an FPGA or uses more energy for the same task you just might want to use the FPGA. I don't have any first hand knowledge of FPGA's but I assume AMD does, especially since their acquisition of Xilinx . I did reputedly run into FPGA's as used for generating PRNG's. Having said that, as the article states, this is only a patent and may never see the light of day in a desktop CPU.
    Reply
  • jimmysmitty
    tommo1982 said:
    FPGA's are used in chip design, are they not? I don't recall them being fast. Reprogrammed to see how a chip might behave, but it's not fast.

    FPGAs are much faster at tasks like hashing, hence why they took over in Bitcoin vs GPUS.

    I don't see this as useful for the every day user as it requires programming made specificaly for said FPGA. But in HPC enviroments where raw throughput is key it can be. They might be looking to integrate it into their higher end server and HPC CPUs to make a more all in one platform. I doubt we will see this in the consumer market.
    Reply
  • JayNor
    Microsoft runs Bing with help from Intel FPGAs. They're apparently good for that.

    https://www.intel.com/content/www/us/en/analytics/artificial-intelligence/accelerating-ai-with-microsoft-project-brainwave.html
    Reply
  • plateLunch
    I smelled this coming as soon as AMD acquired Xilinx. This will fit nicely into the chiplet architecture that AMD has.

    FPGAs are fast. And they don't run instruction sets like a computer. They are "gate arrays", like raw AND and OR gate hardware. The programming of bits tells the chips how to connect the gates on the chip. And from the gates, you can build all kinds of things including regular processors like an ARM core.

    One of the neat things about FPGAs are "cell libraries".
    Cell libraries are complete functions that are designed and sold by somebody else that you plop into your FPGA. And ARM core would be an example. The logic is all programmable so you could alter the instruction set if you wanted to. There are cells you can buy for all kinds of things. One I could see paired up with a Ryzen processor is an encryption cell. Maybe high speed decrypting of data on chip with a custom algorithm that can be easily changed. Or maybe a cell that could decrypt instructions as they are read from memory before they are executed by the CPU. NSA would love that.

    Use your imagination. Anything you can implement in hardware can probably be put into an FPGA and paired up with a Ryzen core.
    Reply
  • TerryLaze
    ARM cores + FPGA, been around for years and is the base for the very popular
    MiSTer project that recreates every old console/home micro/arcade etc.
    https://software.intel.com/content/www/us/en/develop/topics/iot/hardware/fpga-de10-nano.html
    plateLunch said:
    Use your imagination. Anything you can implement in hardware can probably be put into an FPGA and paired up with a Ryzen core.
    Just because it can doesn't mean it's worth it, just like with the mister any half way recent PC core will run things faster.
    But it is a great way to give a CPU abilities it didn't came with, you can encode it with hardware protection/negation for spectre/meltdown or anything that might come up in the future without having to design a whole new CPU.
    Reply
  • overlord
    tommo1982 said:
    FPGA's are used in chip design, are they not? I don't recall them being fast. Reprogrammed to see how a chip might behave, but it's not fast.
    Imagination Technology of PowerVR fame bought a Ray tracing company called Caustic a few years ago, which was FPGA based. It was more power efficient and faster back then!
    https://arstechnica.com/gaming/2009/04/caustic-graphics-launches-real-time-ray-tracing-platform/Fast forward to now, Imagination announced they're targeting Desktop High performance computing.
    https://www.imaginationtech.com/blog/back-in-the-high-performance-game/
    Reply
  • digitalgriffin
    I'm almost certain this will be for Epyc.

    For years Intel made custom CPU extensions for each big client in server space. It made them a lot of money and is their bread and butter.

    This FPGA arrangement would allow these custom extensions to be put into place at a much lower development cost. It will also cause less bloat.

    If they stick them on consumer CPU's we will see another mining boom for algs like etherium and monero. AMD would be shooting themselves in the foot if they did that. While they would make a killing, their traditional markets would die. (Oem desktop/diy/laptop)
    Reply
  • Chung Leong
    jimmysmitty said:
    I don't see this as useful for the every day user as it requires programming made specificaly for said FPGA. But in HPC enviroments where raw throughput is key it can be. They might be looking to integrate it into their higher end server and HPC CPUs to make a more all in one platform. I doubt we will see this in the consumer market.

    If it doesn't take up too much silicon, I can see AMD putting it in all their CPUs simply for marketing purpose.
    Reply
  • TerryLaze
    digitalgriffin said:
    This FPGA arrangement would allow these custom extensions to be put into place at a much lower development cost. It will also cause less bloat.
    And it would be a lot less involvement from AMD which means they would get a lot less money which is not what AMD should be doing right now.
    Intel is making the money because they have to make them custom.
    digitalgriffin said:
    While they would make a killing, their traditional markets would die. (Oem desktop/diy/laptop)
    Don't they have any control where to send their CPUs? This would only be a problem if they would sell all of their CPUs straight trough their webpage without first suppling all of their big customers.
    Reply