Rediscovering RISC-V: Apple M1 Sparks Renewed Interest in Non-x86 Architecture

"With the runaway success of the new ARM-based M1 Macs, non-x86 architectures are getting their closeup," explains a new article at ZDNet.

"RISC-V is getting the most attention from system designers looking to horn-in on Apple's recipe for high performance. Here's why..."RISC-V is, like x86 and ARM, an instruction set architecture (ISA). Unlike x86 and ARM, it is a free and open standard that anyone can use without getting locked into someone else's processor designs or paying costly license fees...

Reaching the end of Moore's Law, we can't just cram more transistors on a chip. Instead, as Apple's A and M series processors show, adding specialized co-processors — for codecs, encryption, AI — to fast general-purpose RISC CPUs can offer stunning application performance and power efficiency. But a proprietary ISA, like ARM, is expensive. Worse, they typically only allow you to use that ISA's hardware designs, unless, of course, you're one of the large companies — like Apple — that can afford a top-tier license and a design team to exploit it. A canned design means architects can't specify tweaks that cut costs and improve performance. An open and free ISA, like RISC-V, eliminates a lot of this cost, giving small companies the ability to optimize their hardware for their applications. As we move intelligence into ever more cost-sensitive applications, using processors that cost a dollar or less, the need for application and cost-optimized processors is greater than ever...

While open operating systems, like Linux, get a lot of attention, ISAs are an even longer-lived foundational technology. The x86 ISA dates back 50 years and today exists as a layer that gets translated to a simpler — and faster — underlying hardware architecture. (I suspect this fact is key to the success of the macOS Rosetta 2 translation from x86 code to Apple's M1 code.)

Of course, an open ISA is only part of the solution. Free standard hardware designs — with tools to design more — and smart compilers to generate optimized code are vital. That larger project is what Berkeley's Adept Lab is working on. As computing continues to permeate civilization, the cost of sub-optimal infrastructure will continue to rise.

Optimizing for efficiency, long-life, and broad application is vital for humanity's progress in a cyber-enabled world.
One RISC-V feature highlighted by the article: 128-bit addressing (in addition to 32 and 64 bit).

https://hardware.slashdot.org/story/21/01/10/2020208/rediscovering-risc-v-apple-m1-sparks-renewed-interest-in-non-x86-architecture