Re: xsrc/50429: Xserver fails to start on Ultra-5 andNetBSD/sparc647.0

[Michael <macallan%netbsd.org@localhost>]

> FWIW, i built kernels from 20141201, 20131201 and 20121201 and
> they all fail with a netbsd-6 userland.  so what ever broke was
> pretty soon after netbsd-6 branched.  i've also confirmed it is
> *not* this change, at least it doesn't help netbsd-7:
> 
> revision 1.75
> date: 2012-05-07 19:25:25 -0700;  author: macallan;  state: Exp;  lines: +3 -3;
> don't enable IO access - we don't use it and at least on some macppc machines
> the IO BAR contains garbage
> should probably be pulled into 6.0

This has nothing to do with the MMIO BAR, and shouldn't have any
influence on mmap()ing the PCI IO space. The mach64 driver doesn't use
PIO access. All this change was intended to do is to not explicitly
enable IO access because some Apple firmware ( Beige G3 is the main
offender IIRC ) doesn't configure it at all so it would overlap with
other devices' IO BARs. Symptoms would be several chips with IO BARs at
0, one legitimately, mach64 because the firmware didn't bother.