On Wed, 9 May 2001, Jun Sun wrote:
> The PCI IO space essentially extends the ISA bus, which effectively removes
> the 0xffff limits.
Note that while there is usually no problem with using addresses beyond
64kB in the PCI I/O space, certain PCI-to-PCI bridges may not pass such
accesses across. So it's best to avoid assigning and using them. That's
why Linux remaps "high" I/O space resources on Alpha, which get set up for
some systems by the SRM console (firmware), e.g. in the system I was using
a few years ago, SRM used to assign addresses around 0x11000 and 0x12000
for the onboard network and SCSI devices, IIRC.
--
+ Maciej W. Rozycki, Technical University of Gdansk, Poland +
+--------------------------------------------------------------+
+ e-mail: macro@ds2.pg.gda.pl, PGP key available +
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