Any ideas about why the cores have been included? The best I can come up with is de-risking shipping RISC-V by doing a trial run.
What are the rational use-cases for these cores, do they use less power?
What are the rational use-cases for these cores, do they use less power?
1. Build out a RISC-V ecosystem for almost zero cost. The value-add is quite large for a segment of potential buyers as they get the same excellent ecosystem, but can target RISC-V as the uArch.
2. De-risk dealing with ARM in the future as their moves in licensing changes foretell a bleak future for licensees
3. Eventually a bargaining chip with ARM on licensing. "Give us favorable terms, or we drop ARM from this design"
Which is nice for a chip they plan to make up to the 2040’s.
Over 10 billion RISC-V devices have shipped, including microcontrollers in millions of Western Digital storage devices, nVidia GPUs, etc. They have no reason to go back to ARM; in many cases it's not even possible as ARM is very restrictive about extensions to the ISA. RISC-V is here to stay.
What remains to be seen is if RISC-V makes it to the CPU big leagues and ends up powering smartphones and such.
1. Arm can increase royalty rates on existing already shipping designs.
2. That increases in royalty rates would be material to the price paid by the end user - making the device ‘expensive’ for the end user.
Neither of these reflect the actual nature of licenses in practice.
The comment I replied to was unduly alarmist though in suggesting Arm could make the Pico ‘expensive’ vs ‘cheap’ now with a royalty increase on an existing license.
This includes myself. I'll always pick a RISC-V option over an ARM one, if I can do so for the purpose.
On that note, I have already ordered some rp2350-based development boards.