[PATCH] mark PCI resource with start 0 as unassigned

[Alan Cox]

On Wed, 01 Aug 2007 18:22:36 +0400
Sergei Shtylyov <sshtylyov at ru.mvista.com> wrote:

> Segher Boessenkool wrote:
> 
> >> setup-pci is for SFF8038i devices. It therefore knows that for  assigned
> >> resources they must be I/O. It also assumes that zero is not a  valid I/O
> >> port just like zero is not a valid IRQ. Stick a real IDE resource  at 
> >> zero and drivers/ide can't cope.
> 
> > But 0 _is_ a valid PCI I/O address.  Do we now have to start
> 
>     I wasn't in PCI 2.1 (later the corresponding passage have disppeared).

SFF controllers often use 0 to indicate a channel isn't configured and
present. Libata and old IDE both assume these semantics for an SFF
IDE device reporting address zero. It matches the hardware behaviour.

I would suggest you don't map one at I/O zero on your PCI.

Alan