Re: [Patch v2] Make PCI extended config space (MMCONFIG) a driver opt-in

Arjan van de Ven
2008-01-13T17:04:19Z

On Sun, 13 Jan 2008 07:43:11 -0500
Tony Camuso <tcamuso@redhat.com> wrote:

> Arjan van de Ven wrote:
> > On Sat, 12 Jan 2008 20:36:59 -0500
> > Tony Camuso <tcamuso@redhat.com> wrote:
> >
> >
> > Just about NOBODY has devices that need the extended config space.
> > At all.
>
> The PCI express spec requires the platform to provide access to this
> space for express-compliance.

PLATFORM not OS :)
Windows isn't using it in the server space, and only in the client space it recently started
considering it.

> More devices will be using this space
> as express becomes the dominant IO bus technology.

sure in like 2009 maybe.

> Which is why Loic's proposal and Ivan's implementation of it is so
> elegant. It solves all these problems in one sweep, and eliminates
> the code rendered cruft by Ivan's patch. A two-fer, by my reckoning.
>
> >> In other words, for x86, I don't think we need to worry about Port
> >> IO config access ever going away at all.
> >
> > You're wrong there. Sad to say, but you're wrong there.
> >
>
> The PCI spec provides for conf1 as an architected solution. It's not
> going away, and especially not in x86 land where Port IO is built-in
> to the CPU.

again sadly you're wrong.

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