Re: __ioremap_at() in 2.4.0-test9-pre2

Hi Paul,

On  19 Sep, this message from Paul Mackerras echoed through cyberspace:

What I am intending to do is to map the I/O space of all the PCI host
bridges in consecutive areas beginning at some address such as
0xff000000, with some amount of space such as 64kB or 1MB per bridge,
whatever is appropriate.  Then we adjust the I/O port numbers in the
pci_dev structures by adding on host_bridge_nr * space_per_bridge.  As
a side effect, isa_io_base (which is really pci_io_base) becomes a
constant.

Good idea. Keep in mind however, that not all bridges reserve the same
amount of space for IO. So you either need to cope with that, or chose
smaller, fixed-size regions, and be prepared to squeeze all devices into
that space. Which shouldn't be a problem, since I can't see why someone
would want to access something larger than a few bytes via IO...

Michel

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