Okay, so is there actual documentation for the SoC used on this critter? I mean a full Databook / Technical Reference Manual, not maybe 30 pages of overview, maybe a list of register base addresses (if you're lucky), and a pile of Linux kernel patches (upstream if you're lucky, but still of less value to someone wanting to actually write code for / port something to the SoC) or an "SDK" containing a bunch of low quality vendor code for the peripherals.

I'd love to see a RISC-V SoC (not just a dinky little MCU) that has real / complete documentation. So far I have yet to find any for any of the various RISC-V based SBCs that have shipped.

This is a Wujian 600 from Alibaba (!). To my knowledge there is currently no publicly available documentation from the chip manufacturer.

Was the idea of an open ISA leading to an open SoC was just wishful thinking?

Not entirely, but the process is very slow.

RISC-V (and SiFive) caught a moment where it could be used is a way to squeeze ARM on pricing. It doesn't really meaningfully create openness on the interesting parts of the stack (core architecture, SoC architecture, etc.) on its own. In that sense, the hype is overblown.

It does _enable_ open-source cores to some degree, but that's it, someone has to take the leap to make a production-ready one. A few companies are trying, but an open-source SoC is even further down the road.

The source RTL for the roughly Arm A72-equivalent cores used in this were open-sourced several years ago.

https://github.com/T-head-Semi/openc910

The same cores are used in the 64 core SG2042 workstation/server SoC.