Linux runs on everything that upstreamed it's drivers, and then almost everything that didn't. By just reverse engineering and guessing.

And, a lot of this firmware is extremely buggy too. Have you see ACPI tables in laptops? But, they work under Linux. They shouldn't, but they do.

What doesn't work is the intersection of closed-source firmware and extremely eccentric or evil firmware. I think a lot of Android parts manufactures don't want to upstream their stuff because it's extremely bad and probably filled to the brim to vulnerabilities.

But, Intel upstreams everything, and so does AMD - and it's only improved their firmware quality.