Info on IO vs. Memory mapped PCI configuration ...

Geert Uytterhoeven geert at
Tue Jan 28 20:41:20 EST 2003

On Mon, 27 Jan 2003, Michel Lanners wrote:
> On  27 Jan, this message from vinai echoed through cyberspace:
> > I am just getting into some driver programming for my work.  I read a
> > bit of the PCI System Architecture book, and it talked about one of the
> > main ways x86 vs the PPC did PCI configuration was through IO vs memory
> > space.
> Configration? That's inherently platform-dependant. The host bridge
> arranges for _some_ way of configuration space access to be available.
> _You_ need to know _how_ you access it from the bridge docs.

It's explained in the PCI System Architecture book for PReP-style PPC host
bridges only. Other host bridges behave different, check out their technical
docs (if you can find them), or look at the arch/ppc/kernel/*pci.c files.



Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds

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