Edit: It also appears Nvidia might also have an x86 license: https://www.nvidia.com/en-us/drivers/uli-m6117c/
Also, https://www.tomshardware.com/pc-components/cpus/intel-licens... (Caveat: The startup is acquainted with the Intel CEO, so it's rare for them to grant the x86 license to non-buddies.)
"Intel provided Rosaic access to an unknown Atom-class core, which enables the company to build its own custom processors based on x86 general-purpose cores, according to the report. The renowned chipmaker plans to ship Rosaic register-transfer level (RTL) code for the Atom processor core, which will let the startup build its custom system-on-chip (SoC) both at Intel Foundry and elsewhere."
What's interesting is that a startup with limited funds would most likely seek a 32-bit x86 license if a) they don't need more than 4GB of RAM, and b), if they don't want to pay AMD for the 64 bit license add-on. :)
OpenFirmware came out of OpenSPARC and is also used by POWER too. Parts of it are used in ARM and RISC-V today (mostly DeviceTree, though arguably quite badly).
Nobody actually wants to make good cores for cheap. Nobody wants to make compatible systems unless forced to. That's why ARM and RISC-V are fragmented messes.
I would personally love to see more Power Systems based projects. Everything is out there, just someone has to want to do something with it.
Fedora Linux even fully supports POWER8+ little-endian systems, and Fedora KDE offers a live ISO you can install on something like a Talos Workstation.
https://lists.libre-soc.org/pipermail/libre-soc-dev/2024-Sep...
Technically just looking at the ISA both SPARC and POWER seem fine enough. So why is nobody interested?
(Talos is interesting but not really an answer to the question, as it seems to be focused on building affordable-ish systems around an existing CPU, not developing new CPU's.)
Also Hitachi's SH-2 & SH-4 patents expired in 2016, so J-core picked up where they left off: https://j-core.org/
MIPS also went open source around 2018: https://www.datacenterknowledge.com/data-center-hardware/mip...