Re: [PATCH] [3/3] PCI segment support

Matthew Wilcox
2003-04-08T16:38:51Z

On Tue, Apr 08, 2003 at 08:38:24PM +0400, Ivan Kokshaysky wrote:
> On Tue, Apr 08, 2003 at 12:44:11AM +0100, Matthew Wilcox wrote:
> > - Add segment to pci_bus.
> > - Change the sysfs name of each device to include a 16-bit segment ID.
>
> First of all, the "segment" name is extremely misleading. PCI spec
> assumes everywhere that "segment" is a group of devices sitting
> on the same wires (ie primary and secondary buses of the PCI-to-PCI
> bridge are *different* segments).

I don't mind changing it to `domain', I prefer the term myself.
ACPI calls it `_SEG' so I went with segment.

> Second, why not
>
> - strcpy(dev->dev.bus_id,dev->slot_name);
> + sprintf(dev->dev.bus_id, "%04x:%s", pci_controller_num(dev),
> + dev->slot_name);
>
> ?

Because it's possible to have multiple pci root bridges in the same
pci domain. This is true on at least HP's ia64 & parisc boxes.

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