On Thu, Apr 24, 2003 at 01:12:11PM -0700, Pete Popov wrote:
>
> > Here's another question:
>
> > What are the goals of the AU1500 PCI auto config? Is it supposed to be a
> > full
> > implementation, or just enough to work with a PCI card? The reason I ask is
> > that the DBAu1500 has only one PCI slot, so a simple implementation would
> > normally suffice.
> >
> > Restated: I don't know if the PCI auto config code was designed to work with
> > all sorts of wacky PCI devices. I don't know if the intention of the code
> > is to
> > support the single PCI slot present on the DbAu1500 development board, or
> > if it
> > is supposed to be more flexible (and complicated).
>
> The MIPS pci auto should work fine with a single PCI bus and it _should_
> be a full implementation. The code was ported from PPC some time ago,
> but sub busses were not tested.
That is not true. pciauto has been working P2P bridges pretty much since day
one.
Usually sub-bus not working is due to type 1 configuration not supported
in pci ops, which is board-dependent code.
I took a brief look of au1x00 pci_ops and it appears it does not support type
1 configuration access. See arch/mips/ddb5xxx/ddb5477/pci_ops.c for one
example on how type 1 configuration being supported.
Jun
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