What does HackerNews think of microwatt?
A tiny Open POWER ISA softcore written in VHDL 2008
If you want an OpenPOWER design to play with, look at Microwatt ( https://github.com/antonblanchard/microwatt ) which is complete enough to boot Linux.
There are at least three open cores, all IBM funded or designed:
https://github.com/antonblanchard/microwatt https://github.com/openpower-cores/a2o https://github.com/openpower-cores/a2i
The last two are older but they work. Microwatt is developing by leaps and bounds.
It's capable of running Linux, some example docs are https://shenki.github.io/boot-linux-on-microwatt/ The toolchain consists of "apt install gcc-powerpc64le-linux-gnu" on Debian, no funny downloads. And if you want to target a Lattice ECP5 board even the FPGA tools are also all open, thanks to Yosys and friends.
All the openpower ISA spec PDFs are available for perusing on the openpower site.
Would microWatts [1] fit that purpose? Not only do you have an Open ISA as in OpenPower, you also have an Open implementation of that ISA. AFAIK RISC-V doesn't have anything similar, only open source design in embedded usage.
Otherwise a low cost POWER10 ( or now Power10 without the capital... and I hate it ) wont make much sense. You are talking about ~30mm2+ per core design. It is huge.
* ppc -> risc-v binary translator, much more tractable with fixed width 32 bit instructions
* running this on an FPGA that already includes a RISC-V core like PolarFire and then instantiate a softcore PPC. hack Haiku to run the PPC processes on that core. Extra bonus points to dynamically instantiate PPC cores to meet load, make fast ones, wide ones, slow ones.
What a time to be alive!
https://github.com/antonblanchard/microwatt
(Disclaimer: minor contributor)
I really liked PA-RISC. I thought it was a clean ISA with good performance at the time and avoided many of the pitfalls of other implementations. I think HP didn't want to pour lots of money into it to keep it competitive, though, and was happy to bail out for Itanium when it was viable. My big C8000 is a power hungry titan, makes the Quad G5 seem thrifty.
https://github.com/antonblanchard/microwatt
https://github.com/antonblanchard/chiselwatt
https://www.efabless.com/projects/29
https://gitlab.raptorengineering.com/kestrel-collaboration/k...
https://openpowerfoundation.org
https://github.com/antonblanchard/microwatt
Unfortunately it isn't gaining any traction. From a Long term Cost perspective it is actually cheaper choosing ARM even if OpenPOWER is free. And ARM is already inexpensive.
And yet the article got interest, since it align with the general public and main stream media view of RSIC-V being the rising star. It is free. It must be better. etc.
I could have repeat most of his point with OpenPOWER. ( microWatts [1] ) And for many application there are lot of reason why OpenPOWER are much better than RISC-V. ( Rather unfortunate IBM is loathed by lots of people in the industry )
Thoughts on OpenPOWER vs ARM v8.2 in terms of ISA?
And for those who may be interested in OpenPOWER, https://github.com/antonblanchard/microwatt
If not, there's at least https://github.com/antonblanchard/microwatt
And the most powerful POWER system you can buy would be something based on the POWER9 processor.
Although I guess it is less relevant now Western Digital has open sourced their RISC-V design as well.
https://github.com/antonblanchard/microwatt
It's also structured very well, quite clean for learning purposes etc. The current goal so far as I know is to perfect this core, and fork for a more complex / powerful variant. Maybe by the time that's done, the open FPGA tooling will have caught up enough to be able to run a usefully fast (~200MHz) POWER soft core, all in FPGA logic...
I'd strongly prefer a ppc64 core over a RISC-V core for one simple reason: we have a wide deployed base of very powerful ppc64 machines, and not having to keep cross compilers and related environments around is a massive streamlining step that we don't even know the full effects of yet (it hasn't been legal until now to have the SoC under development running the same architecture as the high end workstations and servers used to develop [for] it). The demo of using mainline GCC on a POWER box to build a binary for the Microwatt (that would also run on the host with KVM, if desired, for fast trace and debug) was most impressive.
Written initially by a Distinguished Engineer at IBM and sponsored by IBM, this was released when the announcement was made at the OpenPOWER Summit.
You can't fab the same POWER9 that ships from IBM, but like you implied, someone could (eventually) fab a POWER9 CPU built on an open-source core.
The microwatt project [0] was demoed at the OpenPOWER Summit and is an open-source softcore. I'm very interested in watching to see what happens with this project and how much of the ISA they end up implementing. They've run a subset of micropython [1] on it and apparently gotten a few FPGAs working. The Summit talk [2] mentioned DRAM support and Linux support potentially being on the roadmap.
[0]: https://github.com/antonblanchard/microwatt