I actually spent all night debugging call traces caused by the current
stmmac PCS lifetime management, and it was not a pleasant experience.
The code feels like accumulated technical debt that should be cleaned
up.

Russell King will strongly agree with you, if he was around. The
phylink integration into stmmac causes a lot of pain, and he wanted to
rip it all out and start again. But doing that without breaking stuff
is going to be interesting.

If you feel up to it, have a go. But take a good look around first,
make sure you understand the different variant, internal vs external
PCS.

	Andrew