Re: [PATCH] fix ppc ioremap prototype

Matt Porter
2003-09-04T14:15:38Z

On Thu, Sep 04, 2003 at 06:01:39AM -0700, David S. Miller wrote:
> On Thu, 4 Sep 2003 22:59:33 +1000 (EST)
> Paul Mackerras <paulus@samba.org> wrote:
>
> > Perhaps the sensible thing is to have a separate resource tree for
> > each PCI domain (actually two trees, for I/O and memory space),
> > and have them contain bus addresses rather than physical addresses.
>
> I disagree, I think the current model where all resources are
> in a global space makes more sense.

The global space method doesn't allow for proper resource management
in systems with a small floating physical address window but a huge
bus address space to be accessed. MPC8245's DAC scheme is a good
example of this as well as numerous Xscale PCI implementations.
Paul's suggestion would allow the removal of lots of ugly hacks.

-Matt