On Sat, 2013-06-01 at 18:59 +0800, Kevin Hao wrote:

The effect of this change is that the isa_io_base will be 0 and the IO
resource are equal to the virtual address of the IO space. But the IO
functions such as outx/inx should work as well. This is why I ask the
above question. What do you think about this? Are there any subtle bugs
that will be triggered by this?

I don't see any obvious reason why that wouldn't work but like anything
in that area, it needs a bit of testing & hammering to be sure ;-)

In fact it would work on pmac32 as well since those generally don't have
legacy crap either.

So I have no fundamental objection, it just needs testing. My worry is
that we need to make sure we don't break old chrp and I don't have any
to test with. I'm happy to drop support for stuff nobody uses anymore
(we did drop PReP after all and I'm *that* close to drop power3) but as
long as somebody is still using a CHRP RS6K or a Pegasos I can't quite
drop those... And they do have legacy ISA crap to deal with.

Cheers,
Ben.