Hi Tomas,
Hi guys, so far it's only an experiment, but I've started porting RIOT OS to the icoBoard Lattice FPGA / icoSoC / picorv32 RISC-V softcore CPU platform.
The Lattice chip used on the icoBoard is probably the only FPGA device supported by open source tools. And it will be the first FPGA device supported by RIOT OS (AFAIK)
I think you're right with this. I haven't heard of anybody running RIOT
on an FPGA softcore before. Doesn't mean that they don't exist of course 
RIOT OS already supports the HiFive E310 RISC-V MCU, but that is a very different piece of hardware with RISC-V Privileged Architecture support. Still I've been able to reuse some code chunks.
I happen to be working on refactoring the fe310 code to split out the common RISC-V code bits. Mainly to support the gd32vf103 devices from Gigadevice, but any RISC-V MCU should benefit from this. It should at least simplify your porting work in the future.
So far It's only an experiment (and I'm a newbie at this!), but all the important features already work, including shell over UART. It is really fascinating to be able to use a tiny FPGA board this way.
(Personally) I think this makes for a great addition to RIOT. Support for a softcore really opens a lot of options for designers.
If you are interested, you can find the (alpha, experimental!) code at:
GitHub - tstyblo/RIOT-icoboard: RIOT OS for icoBoard FPGA with picorv32 RISC-V core
It would make no sense trying to merge it into the mainline now, as the code needs a lot of testing, comments and improvements. But I'd like to use this opportunity to invite anyone interested in FPGA devices or in the RISC-V platform to check it out.
Looks awesome, thanks for sharing. Is there also a repository with the verilog for the FPGA configuration? Any estimation how many LUT's and other resources it requires from the FPGA?
Best regards,
Koen Zandberg