Microsemi announced a “HiFive Unleashed Expansion Board” built on its PolarFire FPGA that adds PCIe and USB expansion for the RISC-V-based, Linux driven HiFive Unleashed SBC.


cc: @vertigo @jjg @LinuxSocist@icosahedron.website

@h @LinuxSocist@icosahedron.website @vertigo is love to have one of those to play with :)

Aside from that, I need to figure out how much FPGA I need to synthesize a Linux-capable RISC-V core.

I want to start making a RISC-V compute module for one way or another 😁

@jjg @LinuxSocist @h Artix 7 series, or Zynq 7 series chips are known to work, iirc.

@vertigo @h @LinuxSocist@icosahedron.website very cool! Where’s the best place to get started? I’m super green on fpga stuff

@jjg @LinuxSocist @h For fpga kits, probably Digilent would be my first choice.

@vertigo @h @LinuxSocist@icosahedron.website my long-term goal is to design a module that is more-or-less pin (doesn’t need to be as compact, just electrically similar ) compatible with the SOPINE modules I’m using now, but with a RISC-V cpu instead of ARM.

@jjg @LinuxSocist @h You'll definitely need to use a compiler for this. I am certain Digilent's kits won't be pin compatible with much of anything.

If Sifive has bitstreams for download, it'll be for a self-standing computer running Linux.

@vertigo @h @LinuxSocist@icosahedron.website Awesome, thank-you for all the info

So if I want to design a custom board around SiFive's chip, but I can't get the chip, could I use a "raw" FPGA loaded with their bitstream instead?

I imagine I'd start with a dev board to learn the ropes, but I'll have to design a custom board eventually anyway so the dev board doesn't have to do everything or work long-term.

@jjg Asking just out of sheer ignorance... Is there any potential for cross-polination and reuse between Raiden and the Kestrel projects? @LinuxSocist@icosahedron.website @vertigo

@h @LinuxSocist @jjg At this point in time, unlikely. Raiden is focused on HPC, while I'm focusing more on personal computing and freedom. As I scale up, I suppose some future Kestrel can meet Raiden requirements, or Raiden can be scaled down, and we can meet in the middle. But, for now, he's advancing on his project so much faster than I am on mine that I don't see much overlap at all.

@vertigo @jjg @LinuxSocist@icosahedron.website I'm asking because some new directions I'm taking with the work I'm doing increasingly suggest that some sort assistance from machine learning will be useful, and possibly integrated in the normal workflow of the future knowledge worker.
The average personal computer will probably be underpowered for that, and the whole point of all these projects is to limit or remove the dependence from the corporate data centre.

@LinuxSocist@icosahedron.website @jjg @vertigo

In that light, personal HPC, together with personal desktop computing makes total sense.

It's obvious that it's only reasonable to keep projects decoupled and reusable, but I would personally suggest to consider the potential for some periodic loose coordination in the future, to alleviate integration problems later.

@h @jjg @LinuxSocist If a future Raiden needs a set of motherboard peripherals (video, ps/2 keyboard and mouse, etc), I can offer that. But, Linux drivers will need to be written for them, which encourages JJG to just use of the shelf RISC-V parts for that anyway.

I hate top sounds like I'm cutting his project off, but it really is not economical to follow Kestrel-3 project anymore.

@vertigo Sorry, I'm not following. You mean that the Kestrel-3 project is in hiatus because the economics of it don't make sense at this time?

@LinuxSocist@icosahedron.website @jjg

@h @jjg @LinuxSocist No. But it may as well be. At the rate JJG is progressing on his project relative to me on mine, he'll have a working RISC-V module running Linux before I even have an integrated processor and I/O chipset. I will still need to write the OS after that. And off have no ecosystem, since I'll be is only user.

I don't anticipate having a working CPU module (with all of 1MB of RAM!) until late next year. Add another year for I/O.


I appreciate your optimism @vertigo, but I might still be soldering LED's by this time next year 😂

@LinuxSocist@icosahedron.website @h

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