Help me understand this better.

From what I have read online, since arm just licenses their ISA and each vendor’s CPU design can differ vastly from one another unlike x86 which is standard and only between amd and Intel. So the Linux support is hit or miss for arm CPUs and is dependent on vendor.

How is RISC-V better at this?. Now since it is open source, there may not be even some standard ISA like arm-v8. Isn’t it even fragmented and harder to support all different type CPUs?

  • @pivot_root
    33•1 month ago

    TL;DR: While Intel had their heads shoved up their ass making the Itanium architecture, AMD made a 64-bit variant of x86 that was backward compatible with the older x86 ISA. Technology moved on, and amd64 was adopted while Intel kept trying and failing to push their binary-incompatible architecture.

    Eventually, Intel had to give up and adopt AMD’s amd64 ISA. In exchange for letting them use it, Intel lets AMD use the older x86 ISA.

    • @[email protected]
      42•1 month ago

      AMD were already using the x86 ISA long before amd64.

      https://en.m.wikipedia.org/wiki/AMD

      Intel had introduced the first x86 microprocessors in 1978.[51] In 1981, IBM created its PC, and wanted Intel’s x86 processors, but only under the condition that Intel also provide a second-source manufacturer for its patented x86 microprocessors.[12] Intel and AMD entered into a 10-year technology exchange agreement

      AMD were also second source for some other Intel logic chips before that deal.

      • @pivot_root
        14•1 month ago

        I was only going for explaining why AMD still continues to have the license to the x86 instruction set in modern times, but I appreciate the added historical context to explain to others how they originally had the rights to use it.

    • @[email protected]
      4•1 month ago

      Itanium also failed miserably in performance and everything else it set out to deliver. While being ridiculously expensive.