I want to buy RISC-V, both to play with and to support the cause. What are my options like and should I buy something now or wait for the next generation?
https://dev.sifive.com/freedom-soc/evaluate/fpga/
The FPGA board can be used for other things too. If you are really adventurous, I'd suggest buying a FPGA board with better chip so you can fit in larger IP blocks in the future. It will work perfectly fine as a replacement for the above FPGA kit I've linked to.
My suggestion would be this[1]. It has a pretty large LUT count so you can go nuts. The RAM and Ethernet will be pretty useful if you want to run linux[2] and test out stuff. It'll be a bit hard to run linux on it right now.
On the other hand, you can choose a Parallela board[3] which comes with a FPGA chip along with a new (soon to be retired) arch called epiphany. Here[4] is a GSoC project which runs linux on that board using the FPGA.
[1]: http://store.digilentinc.com/nexys-4-ddr-artix-7-fpga-traine... [2]: https://github.com/riscv/riscv-linux [3]: https://www.parallella.org/ [4]: https://github.com/eliaskousk/parallella-riscv
https://www.sifive.com/products/freedom/
today, is a dev board
https://dev.sifive.com/freedom-soc/evaluate/fpga/
that costs around 3500 USD:
https://www.avnet.com/shop/us/p/kits-and-tools/development-k...
Do anyone here know what kind of "classic pc" performance one is likely to get out of a board like that? Could you get on the order of low-end pc (~500 dollar soc / netbook with real gigabit ethernet, sata6 and usb3) from something like that, if paired up with a reasonable cpu design?
Even in a best-case scenario, this is nowhere near a low end consumer PC.
edit: For reference, my 5 years old Thinkpad x230 does around 7400 DMIPs per core.
[1] - https://www.xilinx.com/products/design-tools/microblaze.html
Both the $99 and $3500 FPGA boards run a Rocket CPU at 65 MHz, which is pretty slow, though faster than you get with a software cycle-accurate simulator on a workstation.
It looks like the first dev board that would be capable of running linux will likely be the lowRISC project.
"We are expecting to crowdfund an initial instantiation of the lowRISC platform during the course of 2017" http://www.lowrisc.org/
Ideally, they'll both succeed.
The Freedom Unleashed platform is coming down the pipe, and you can pre-evaluate it on an FPGA board (albeit at lower frequency, and fairly pricy since it's a complex design and requires a fairly large FPGA to prototype). I won't pretend to know when they'll have a standard Freedom U500 SoC dev board, but it will have multiple cores, PCIe 3.0, USB 3, Gigabit ethernet, and DDR4 compatibility according to their website[1].
Others have the SiFive chip, but if you want to boot Linux then your best option currently is running Rocket on an FPGA kit. I expect that we'll soon have more options. If you just want to play around, then I'd recommend Spike or Fabrice's https://bellard.org/riscvemu/