If we don't like "uart8250,io,0x3f8" (which I agree is awfully clunky),
we could easily add something like "console=com1" which encapsulated
the well-defined PC concept.
It would be similar to "earlyprintk=ttyS0",
and if it could be made *enough* like it, maybe "earlyprintk=ttyS0"
could be dropped.
I also see the recent "earlyprintk=hsu" patch from Feng Tang, and I
wonder whether that could be recast in the "console=hsu" style. Like
"com1", "hsu" is apparently enough to specifically identify a device.
I think it's nicer to extend "console=" in ways that allow early
devices, because then users don't have to mess with both "console="
and "earlyprintk=". The 8250_early driver has a reasonable model
of switching from the early device to the real one automatically,
so maybe something like this is all we would need: