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> I'm still a little unclear on RISC-V's goals Maybe a bit cynic, but given their churn in the lower level specifications (supervisor mode and up) my guess is:

> I'm still a little unclear on RISC-V's goals Maybe a bit cynic, but given their churn in the lower level specifications (supervisor mode and up) my guess is: Main goal: write lots of theses and papers and obtain degrees. Secondary goal: have an unencumbered ISA to help with the main goal. Everything else depends on those who adopt the ISA. If some org is willing to spend the multi-million $$$ necessary to design a high-performance desktop class CPU (and more to make it a reality), it will happen. Those low-end chips are easier to do, and an easier market to serve: The ISA's license fees are a bigger chunk of the chip's price, so RISC-V dropping that to 0 helps more. You also don't need to build a high-end chip that blasts everything else out of the water before your newcomer is even considered, since in the microcontroller market there are several pockets of "good enough". If that works out, there might be attempts to scale up later (when they have experience and financial resources to work with).

microcolonel 9y ago
> Everything else depends on those who adopt the ISA. If some org is willing to spend the multi-million $$$ necessary to design a high-performance desktop class CPU (and more to make it a reality), it will happen. It's a good sign that NVIDIA and Qualcomm are both integrating RISC-V for embedded controllers on their chipsets. This means that there will be experience and maybe R&D going into RISC-V cores at these two massive vendors of embedded and mobile CPUs. It is not inconceivable that RISC-V could... cross-contaminate to their high-performance application processor business.
- pjmlp 9y ago
  Yeah, but will they give it back in some form? The examples of contributions from big players using BSD like licenses, specially in the embedded space, proves otherwise.
  - imtringued 9y ago
    Why does that matter? The only thing they need to do is correctly implement the RISC-V ISA instead of a proprietary ISA.
    - pjmlp 9y ago
      Because you will get into the scenario of commercial vendors basing their ISAs on RISC-V ISA with extensions not made available to the community. Thus making the base RISC-V ISA kind of useless for software that one might actually care about.
      - microcolonel 9y ago
        Vendors benefit from standardization when it comes to the ISA, especially in the commodity/interchangeable market. Qualcomm is currently competing with other vendors to run the same software (Android or Windows). If they make ISA extensions which are not likely to be used by that software, then they're probably wasting their time, or those extensions were not that useful for the general community to begin with. Useful ISA extensions are likely to remain royalty free at least, if not standardized at the level of the foundation; but if they don't, it's not the end of the world.
        pjmlp 9y ago
        Except that is exactly what happens on ARM, for example.
        microcolonel 9y ago
        What proprietary ARM extension are you just dying to have?
        pjmlp 9y ago
        Personally I don't care about RISC V's future, was just making the point things might not turn out as the comunity hopes for. To reply to your question, as a developer I don't care about ARM vendor specific features, because Android hides them for me. However as a consumer, they do impact updates.
tyingq 9y ago
Lowrisc.org is worth checking out if you're hoping for something that could run Linux. I like their concept of minion cores, as it makes them more competing in the Beaglebone space, versus the Raspberry PI space. The ability to do real-time-ish IO via offloaded processors is a win. And it doesn't need to end up in a $5 board to succeed.
Someone 9y ago
”The ISA's license fees are a bigger chunk of the chip's price” I don’t know much of CPU IP licensing, but I would think one pays more for the design of the CPU than for the ISA. And that’s probably for the better, because, if one pays for the ISA, but the RISC-V ISA is free, how are ‘they’ going to get ”financial resources to work with”.?
- pgeorgi 9y ago
  > I don’t know much of CPU IP licensing, but I would think one pays more for the design of the CPU than for the ISA. You have a couple of options: - Use a ready made CPU design (eg. Cortex-M) and pay license $$ for each chip sold. - Use an existing ISA (eg. ARMv4), build your own CPU around it and pay license $ for each chip sold. - Use RISC-V, build your own CPU around it and pocket those $ you'd otherwise pay for the ISA license (or reduce your price to become more competitive, or something inbetween) (And then there #4: Design your own ISA. Now you also have to deal with standard software: compilers, kernels, some libraries. Still may make sense in some cases, but why go through the trouble if all you want is to save some pennies per chip on the ISA?) In all but the first case, your CPU design is a one-time cost that becomes marginal over the (hopefully many) chips you sell. Especially microcontrollers can be _very_ high volume where this makes sense (more so with the IoT hype that's going on). Which is why I think it's a wise idea for them to aim for that market first and build up experience and a war chest.
noir_lord 9y ago
Something I was thinking about the other day was what will happen when we hit mass market process limits, Intel has always stayed ahead of it's competitors outside of x86 land even when their architectures where not competitive by having the best process but when the rest of the world catches up and suddenly I can order a 20bn transistor 3nm (or whatever) chip with RISC-V cores then things start to look a lot different. Throw in that we already have a mainstream (if you squint) desktop OS that is a compile away (and has driver support for a lot of hardware) and if I where Intel I'd be worried in the mid-term. Hell for the first time since the first AMD64's came out Chipzilla is looking vulnerable from the AMD direction, a surprise to a lot of people (including myself, I bought a Ryzen 1700 for work back in late May and I've been astounded by the performance per £ on my workloads).
- subwayclub 9y ago
  Intel has a lot of threats lately. Things seem to be moving towards a small die and MCM strategy to get better yields and move investment towards the package and FSB. AMD made a huge investment in that direction with Zen arch and Infinity Fabric - Threadripper's big package and high core count has opened a new tier of enthusiast desktops - and they may have plans for furthering that on the GPU side of things(Vega is positioned for efficiency at lower wattage, which is poorly reflected in the "hot-and-loud" flagship releases. It's expected to pair well with Zen in the forthcoming Raven Ridge APUs though.) Intel shares with Nvidia(also currently using large dies) a limited form of performance leadership at the high end that may be eroded in the face of these shifts. Most of the market is going to see more benefit from more cores instead of faster cores with the current conditions. That might be less true once we're talking about a baseline of 16 or 32 cores, but 2 is proving to be too few for current workloads. And that's just their nearest competitor. ARM SOCs have consumed the mobile market and are creeping upwards. My ARM Chromebook makes a pretty good Linux desktop too, and you can practically trip over RaspPi devices.
  - noir_lord 9y ago
    I'm nothing but happy with my Ryzen 1700, I nearly held off a year buying my new laptop because I wanted to see what their mobile chips where like. In the end I went with an i7-7700HQ because I simply couldn't make my old laptop last any longer, 8GB ram just wasn't enough for my workflow. If the mobile Ryzens are amazing I'm going to regret that maybe.

microcolonel 9y ago

> Everything else depends on those who adopt the ISA. If some org is willing to spend the multi-million $$$ necessary to design a high-performance desktop class CPU (and more to make it a reality), it will happen. It's a good sign that NVIDIA and Qualcomm are both integrating RISC-V for embedded controllers on their chipsets. This means that there will be experience and maybe R&D going into RISC-V cores at these two massive vendors of embedded and mobile CPUs. It is not inconceivable that RISC-V could... cross-contaminate to their high-performance application processor business.

pjmlp 9y ago
Yeah, but will they give it back in some form? The examples of contributions from big players using BSD like licenses, specially in the embedded space, proves otherwise.
- imtringued 9y ago
  Why does that matter? The only thing they need to do is correctly implement the RISC-V ISA instead of a proprietary ISA.
  - pjmlp 9y ago
    Because you will get into the scenario of commercial vendors basing their ISAs on RISC-V ISA with extensions not made available to the community. Thus making the base RISC-V ISA kind of useless for software that one might actually care about.
    - microcolonel 9y ago
      Vendors benefit from standardization when it comes to the ISA, especially in the commodity/interchangeable market. Qualcomm is currently competing with other vendors to run the same software (Android or Windows). If they make ISA extensions which are not likely to be used by that software, then they're probably wasting their time, or those extensions were not that useful for the general community to begin with. Useful ISA extensions are likely to remain royalty free at least, if not standardized at the level of the foundation; but if they don't, it's not the end of the world.
      - pjmlp 9y ago
        Except that is exactly what happens on ARM, for example.
        microcolonel 9y ago
        What proprietary ARM extension are you just dying to have?
        pjmlp 9y ago
        Personally I don't care about RISC V's future, was just making the point things might not turn out as the comunity hopes for. To reply to your question, as a developer I don't care about ARM vendor specific features, because Android hides them for me. However as a consumer, they do impact updates.

tyingq 9y ago

Lowrisc.org is worth checking out if you're hoping for something that could run Linux. I like their concept of minion cores, as it makes them more competing in the Beaglebone space, versus the Raspberry PI space. The ability to do real-time-ish IO via offloaded processors is a win. And it doesn't need to end up in a $5 board to succeed.

Someone 9y ago

”The ISA's license fees are a bigger chunk of the chip's price” I don’t know much of CPU IP licensing, but I would think one pays more for the design of the CPU than for the ISA. And that’s probably for the better, because, if one pays for the ISA, but the RISC-V ISA is free, how are ‘they’ going to get ”financial resources to work with”.?

pgeorgi 9y ago
> I don’t know much of CPU IP licensing, but I would think one pays more for the design of the CPU than for the ISA. You have a couple of options: - Use a ready made CPU design (eg. Cortex-M) and pay license $$ for each chip sold. - Use an existing ISA (eg. ARMv4), build your own CPU around it and pay license $ for each chip sold. - Use RISC-V, build your own CPU around it and pocket those $ you'd otherwise pay for the ISA license (or reduce your price to become more competitive, or something inbetween) (And then there #4: Design your own ISA. Now you also have to deal with standard software: compilers, kernels, some libraries. Still may make sense in some cases, but why go through the trouble if all you want is to save some pennies per chip on the ISA?) In all but the first case, your CPU design is a one-time cost that becomes marginal over the (hopefully many) chips you sell. Especially microcontrollers can be _very_ high volume where this makes sense (more so with the IoT hype that's going on). Which is why I think it's a wise idea for them to aim for that market first and build up experience and a war chest.

noir_lord 9y ago

Something I was thinking about the other day was what will happen when we hit mass market process limits, Intel has always stayed ahead of it's competitors outside of x86 land even when their architectures where not competitive by having the best process but when the rest of the world catches up and suddenly I can order a 20bn transistor 3nm (or whatever) chip with RISC-V cores then things start to look a lot different. Throw in that we already have a mainstream (if you squint) desktop OS that is a compile away (and has driver support for a lot of hardware) and if I where Intel I'd be worried in the mid-term. Hell for the first time since the first AMD64's came out Chipzilla is looking vulnerable from the AMD direction, a surprise to a lot of people (including myself, I bought a Ryzen 1700 for work back in late May and I've been astounded by the performance per £ on my workloads).

subwayclub 9y ago
Intel has a lot of threats lately. Things seem to be moving towards a small die and MCM strategy to get better yields and move investment towards the package and FSB. AMD made a huge investment in that direction with Zen arch and Infinity Fabric - Threadripper's big package and high core count has opened a new tier of enthusiast desktops - and they may have plans for furthering that on the GPU side of things(Vega is positioned for efficiency at lower wattage, which is poorly reflected in the "hot-and-loud" flagship releases. It's expected to pair well with Zen in the forthcoming Raven Ridge APUs though.) Intel shares with Nvidia(also currently using large dies) a limited form of performance leadership at the high end that may be eroded in the face of these shifts. Most of the market is going to see more benefit from more cores instead of faster cores with the current conditions. That might be less true once we're talking about a baseline of 16 or 32 cores, but 2 is proving to be too few for current workloads. And that's just their nearest competitor. ARM SOCs have consumed the mobile market and are creeping upwards. My ARM Chromebook makes a pretty good Linux desktop too, and you can practically trip over RaspPi devices.
- noir_lord 9y ago
  I'm nothing but happy with my Ryzen 1700, I nearly held off a year buying my new laptop because I wanted to see what their mobile chips where like. In the end I went with an i7-7700HQ because I simply couldn't make my old laptop last any longer, 8GB ram just wasn't enough for my workflow. If the mobile Ryzens are amazing I'm going to regret that maybe.