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Subject: Re: [PATCH 08/18] PCI, powerpc: Register busn_res for root buses
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Bjorn Helgaas <bhelgaas@google.com>
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On Tue, 2012-02-28 at 16:31 -0700, Bjorn Helgaas wrote:
> We may need mechanism to say "don't trust this info from the
> firmware," but we should be able to figure out a way that doesn't
> penalize platforms that do everything correctly.  The current patch
> breaks these scenarios even when the platform firmware is 100%
> correct.

On the other hand, our firmwares tend not to be and the vast majority of
our platforms have separate bus number domains (In fact I'm not sure
whether we have one that actually splits bus numbers or not, maybe some
ancient Apple gear, I need to double check).

We did use to force renumbering on macs to avoid bus number collisions
between domains because of ancient X servers that didn't do domains
properly but I think we dropped that.

Cheers,
Ben.