Re: Cardbus

Linus Torvalds
2002-06-15T21:58:36Z

On Sat, 15 Jun 2002, Paul Mackerras wrote:
>
> IIRC someone told me that we had to do the "assuming transparent" bit
> because of buggy PCI-PCI bridges used on some PCs. Can anyone
> enlighten me on the details of that?

It has nothing to do with "buggy" PCI-PCI bridges, and everything to do
with the fact that a lot of bridges seem to extend on the official PCI
bridge interface in various ways. In particular, it seems to be fairly
common to have the _real_ bridging information in the chip-specific range
(PCI config area 0x40+) instead of in the official "2 mem resources, 2 IO
resources" place.

I think even some bog-standard Intel PCI bridge did exactly this. But all
my pdf files are at work right now.

Linus