Re:RISC-V is succeeding
by admax88qqq on Tuesday March 01, 2022 @02:37PM
(#30518940)
Totally, all the more reason that the specific ISA is less important than the implementation/micro-arch.
Why pay for ARM if you can retarget to RISC-V and still retain most of the benefits of your designs.
Re:RISC-V is succeeding
by YorkshireSeason on Tuesday March 01, 2022 @03:41PM
(#30519695)
As "baq" also says: you pay Arm (or Apple, or Qualcomm or ...) for the micro-architecture. I expect Arm to drop licensing costs for their ISA to zero to compete with RISC-V at the low end.
Right now, the Arm ISA has much better micro-architectures than RISC-V, why bother with RISC-V? I think this will change over the next 5 years. One of the ways to change this could be Arm selling RISC-V implementations.
Of course there are also dangers in RISC-V: one is that we will get too many RISC-V versions, so no stable software ecosystem emerges for any single one of them. Adapting Linux, GCC and so on to your specific version of RISC-V (or any processor really) is rather expensive.
It is not that difficult to re-target a micro-architecture (what you call implementation) to a new ISA, especially if the ISAs relatively close, as most modern ISAs are. RISC-V and Arm ISAs are an example where that should be especially easy.