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From: Bjorn Helgaas <bhelgaas@google.com>
Date: Mon, 4 Apr 2011 09:25:20 -0600
Message-ID: <BANLkTimBD=NfFKGpy0ZTnT9Dcu=dkTHxZg@mail.gmail.com>
Subject: Re: [RFC/PATCH] of: Match PCI devices to OF nodes generically
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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On Mon, Apr 4, 2011 at 1:37 AM, Benjamin Herrenschmidt
<benh@kernel.crashing.org> wrote:

> powerpc has two different ways of matching PCI devices to their
> corresponding OF node (if any) for historical reasons. The ppc64 one
> does a scan looking for matching bus/dev/fn, while the ppc32 one does a
> scan looking only for matching dev/fn on each level in order to be
> agnostic to busses being renumbered (which Linux does on some
> platforms).
>
> This removes both and instead moves the matching code to the PCI core
> itself. It's the most logical place to do it: when a pci_dev is created,
> we know the parent and thus can do a single level scan for the matching
> device_node (if any).

Some of this is reminiscent of the ACPI/PCI binding we do on x86/ia64,
e.g., acpi_get_pci_dev() and the stuff in drivers/acpi/glue.c.  Have
you looked at that to see if there's any hope of covering both OF and
ACPI with something more generic?

Bjorn