[spash]

From https://libreboot.org/faq/#amd

# Why is the latest AMD hardware unsupported in libreboot?

It is extremely unlikely that any post-2013 AMD hardware will ever be supported in libreboot, due to severe security and freedom issues; so severe, that the libreboot project recommends avoiding all modern AMD hardware. If you have an AMD based system affected by the problems described below, then you should get rid of it as soon as possible. The main issues are as follows:

# AMD Platform Security Processor (PSP)

This is basically AMD's own version of the Intel Management Engine. It has all of the same basic security and freedom issues, although the implementation is wildly different.

[userbinator]

The PSP is an ARM core with TrustZone technology, built onto the main CPU die.

That sounds even worse than ME:

Intel Management Engine (ME) is a separate computing environment physically located in the (G)MCH chip.

Theoretically, if a third-party can figure out how to make a compatible MCH they can use Intel CPUs without ME, but that is impossible with AMD's design.

Then again, developing a compatible MCH would be nontrivial too --- the last truly "open" x86 bus interface was probably Socket 370 (still in use by VIA and others), and the later bus interfaces are such high speed that they require some very expensive signal analysers to even see the communications properly.