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10 billion RISC-V cores were shipped last year - mostly you wont see them because they're heavily embedded - in disk drives/etc - used to be every flash drive had an ARM core in it and paid a few pennies to ARM, that's likely to change quickly
Shipped last year or shipped in total?
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RV32 will turn out to be the 8051 of the present. The 8051 was the Doge Dart of embedded automation. I bought a book in Vietnamese in Vietnam in 2005 on embedded development hardware and software for the 8051. If the diagrams were any indication of the quality, the writing was excellent.
I highly doubt it. As "reduced" as RISC-V is, 8051 is still tiny in comparison. 8051s are used in applications where a 4-bit MCU (yes, they do exist and are still in widespread use) is not quite enough, or they'd have chosen one of those instead.
A basic RV32 CPU is down to 500-700 LUT.
https://github.com/YosysHQ/picorv32
https://github.com/olofk/serv
https://github.com/MicroCoreLabs/Projects/tree/master/MCL51
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There's lots of open source RISC-V cores - but can't be any fully OS ARM ones (even if someone's made a n OS ARM core you still have to pay ARM a royalty) The big advantage to rolling your own private ISA is that there's already a rich compiler and O/S ecosystem for RISC-V while if you do use RISC-V it's all already there for you. It really does feel like a second generation 'barn raising'
> but can't be any fully OS ARM ones (even if someone's made an OS ARM core you still have to pay ARM a royalty) Wait long enough and you can. Even if you can’t work around them, patents expire, and you can copy the instruction set for reasons of compatibility. Trademarks don’t automatically expire, though, so unless the trademark gets genericized ( https://en.wikipedia.org/wiki/Generic_trademark ) what you can’t do…
And being blacklisted by ARM might hurt your business when you do actually need to buy something from them.
Jim Keller's slide [1] on RISC-V. Simple words. Grug like. [1] https://www.techgoing.com/jim-keller-innovation-is-happening...
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What benefits does Linux/BSD have over Windows, as a highly productive development environment outside of all the possibilities it had opened by being open/free ?
IMO the comparison is similar but it's just not quite the same thing. Don't get me wrong - it's a big deal to have this popular open ISA. But I just don't think it's anywhere near as big a deal as Linux is/was.
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I highly doubt it. As "reduced" as RISC-V is, 8051 is still tiny in comparison. 8051s are used in applications where a 4-bit MCU (yes, they do exist and are still in widespread use) is not quite enough, or they'd have chosen one of those instead.
There's a community doing "fpga golf". That is, reducing the number of LUT required to implement a CPU of a given ISA. A basic RV32 CPU is down to 500-700 LUT. https://github.com/YosysHQ/picorv32 https://github.com/olofk/serv A minimal 8051 requires about 300 LUT. https://github.com/MicroCoreLabs/Projects/tree/master/MCL51 Not sure how this translates from an FPGA to a transistor count. But RV32 and 8051 should be wi…
(oh and 8051 are a pain to work with, they've taken far too much of my lifetime, they need the stake thru the heart thing)
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There's a community doing "fpga golf". That is, reducing the number of LUT required to implement a CPU of a given ISA. A basic RV32 CPU is down to 500-700 LUT. https://github.com/YosysHQ/picorv32 https://github.com/olofk/serv A minimal 8051 requires about 300 LUT. https://github.com/MicroCoreLabs/Projects/tree/master/MCL51 Not sure how this translates from an FPGA to a transistor count. But RV32 and 8051 should be wi…
If all you're doing is making a core with a little ROM, a USB interface and a flash interface chances are your design is pad limited - it probably doesn't matter which CPU you use provided it's tinyish (oh and 8051 are a pain to work with, they've taken far too much of my lifetime, they need the stake thru the heart thing)
An interesting observation is that RV32 has excellent code density. Meaning, in this sort of scenario, the ROM could be much smaller, or fit way more code at the same size.
What benefits does RISC-V have over ARM besides it being open/free?
smaller instruction set, Arm has grown, reference manual is over 6k pages smaller easier to read specs easier to get new features ratified, org is a steward, isn't seeking rents easy to add custom instructions lots of OSH implementations to choose from large 3rd party ecosystem, IP, compilers, OS, etc.
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smaller instruction set, Arm has grown, reference manual is over 6k pages smaller easier to read specs easier to get new features ratified, org is a steward, isn't seeking rents easy to add custom instructions lots of OSH implementations to choose from large 3rd party ecosystem, IP, compilers, OS, etc.
Smaller instruction set and shorter reference manual aren’t necessarily good attributes. The risc-v reference manual is short because in part because it is has terse-to-vague descriptions of things (not great for a specification) and because the ARM ARM specifies a bunch of things which are omitted from the RISC-V architecture spec, which either implementors will have to design themselves or the RISC-V org will event…
10 billion RISC-V cores were shipped last year - mostly you wont see them because they're heavily embedded - in disk drives/etc - used to be every flash drive had an ARM core in it and paid a few pennies to ARM, that's likely to change quickly
It's more likely that RISC-V replaces MIPS than ARM, although it's certainly competing for the latter too. ...and USB flash drives are more likely to be based on 8051s than ARM in volume.
The company that owns MIPS, Imagination Technologies, has entirely dropped the MIPS ISA to instead focus in designing RISC-V cores.