May 4, 2023

RISC-V -- PMS and groupthink

This is somewhat of an "axe grinding" page, so consider yourself warned. I spend a lot of time reading posts on Hackaday, and I enjoy it as a source of information and sometimes inspiration. I have noticed a mentality there that puzzles me, an ongoing advocacy of the RISC-V processor.

Evaluated on its technical merits, it is a perfectly fine RISC processor and a reasonable alternative to the ARM in many applications. I see it as neither better nor worse. It has a clean architecture, but doesn't break any new ground that I am aware of. I don't know about things like power consumptions, gate count for a given implementation, limits to clock speed, and such like.

What irritates me is that it is advocated as superior because it is "open". As near as I can tell, this means that you can build a RISC-V core without paying fees to a designer (in contrast to ARM, where fees including royalities must be paid). Two aspects of this make this irrelevant to me:

This is why I call RISC-V advocacy "PMS" (perceived moral superiority). Somehow the fact that the RISC-V architecture is open is viewed as virtuous. This mindset seems to have elevated itself to an unthinking "groupthink". The chant is: "it is open, it is better".

I recently tried to make some comments along this line after reading the following article on Hackaday:

The project involves putting the 400 BGA Octavo systems OSD3358 chip onto a 4 layer board to allow it to be incorporated as a linux capable engine without having to solder the 400 pin chip. The article ended with the comment: 
Might we suggest a future version using RISC-V?
I took issue with this as follows:
I've never understood the fascination with RISC-V. No, by all means no. Give me the Beagle and the ARM thank you oh so much. I have had wonderful success with the beagle in various forms, documentation is superb, ARM is well understood with fabulous documentation. The price is right. But somehow the word "open" has gotten attached to RISC-V. To my taste, what I just described is about as "open" as I might like.

The RISC-V thing involves what I call "PMS" (perceived moral superiority) that is somehow linked to RISC-V not involving licensing. I don't see the benefit of this unless you are a silicon foundry -- it certainly is of no benefit to the end user hobbyist.

I submitted this twice only to have it rejected both times.
Feedback? Questions? Drop me a line!

Tom's Computer Info / tom@mmto.org