I know about OpenCores, but it consists of, well, cores. I’m looking for fully realized projects, with controller, glue logic, external interfaces, test benches, multiple hardware realizations, all the tedious stuff you have to do to make a working version>1 device. That is, what do you do with the cores? To me it seems analogous to the difference between a B-tree library and PostgreSQL. White Rabbit looks great, thanks for the pointer!

Ah, I see. I'm coming from a background where nearly everything is a bespoke one-off design. (After all, if you're making a million of something, why use an FPGA?) My colleagues are usually looking for flexible, multipurpose building blocks that they can assemble into something unusual. That's the main intent for SatCat5, though we do include fully-realized example designs that may be closer to what you're looking for.

As the OP says, FPGAs are kind of niche and devoted to specialized applications. For example there's Corundum[0] for in-network compute, kind of exotic and maybe too pricey for a hobbyist. The biggest open-source thing out there is of course MiSTer, but it is tied to a particular old dev board and toolchain last I checked.

>what do you _do_ with the cores?

I mean, this is kind of the problem, but in a way it's a funny problem. The strength and the curse of FPGAs is that they can become almost anything you want. However getting that sea of logic into the desired form requires knowledge of the FPGA family, the tools, the hardware, and digital design in general. The "tedious stuff" unfortunately makes up a great deal of FPGA work! Many days I feel like a glorified plumber...

As far as cores go, in FPGA land, the vendor would probably already provide a core (IP, in hardware parlance) for say fooing bars, that is easier to use and probably a far sight more reliable than the project on OpenCores. (Which probably hasn't been touched in a decade, is written in VHDL-87, is using Wishbone when you want AXI, and lacks a test suite.)

As a hobbyist, you might search and find the project on OpenCores, but be scared away by the cruftiness. You then write your own foo_bars module, thereby learning a great deal, but contributing to the fragmentation problem. Plus seeding the internet with weird code with corner-case bugs for LLMs to trip over.

[0]: https://github.com/corundum/corundum

In software world, I can point someone to PostgreSQL (I’ll keep using that example, though my point is there are lots of examples!) to see a fully-realized product including all the tedious stuff. And it’s nothing to do with hobbyists, this exact codebase is the same one that keeps billion-dollar businesses running.

What are the equivalent projects of equal professionalism and completeness in open hardware world? Maybe Open Compute Project?

Or does the jump to “hobbyists” indicate there is very little like that, in other words virtually all serious hardware is not open?

Most serious hardware is not going to be open. I think this is mainly because hardware companies need higher margins, because working with physical things costs money. For most companies that use FPGAs, the custom stuff is the secret sauce, kept under lock and key. Most open source stuff out there is either hobby, or effectively serves as an advertisement for design services.

I'm not that familiar with OCP but certainly driving commodity hardware costs down is a valid object. My interest is more in specialized hardware at the board level. I believe CERN and other high-energy physics labs collaborate on designs, but I've been out of the field for a long time. Much of that sort of hardware doesn't have use in the industry at large; historically speaking, if there is demand, the model has been to spin out a small company to sell equipment to other labs.

The only category of core with what I'd call a big open-source impact is RISC-V processors, as you mentioned above. This is because a small processor is often useful on a non-SoC FPGA. But there were already free-as-in-beer microprocessors available from the FPGA vendors, so RISC-V adoption is really more of a political/philosophical choice.

When people talk about someday having an OSHW scene approaching the vibrancy of the FOSS scene, I'm not so sure there are parallels. People talk about having open tooling, but the existing tooling is already free-as-in-beer (for the device types most people could afford, anyway). The cost of the vendor IPs is already baked into the cost of the device, so you'd still be paying for it. The argument is that open source tools will be easier to use, but I haven't found that to be the case at this point in time.

I think that hardware is just a fundamentally different medium from software, and attracts different kinds of people. It's a comparatively smaller crowd, who tend to be lone wolves. Maybe someday there'll be a critical mass.