Adding an ops to struct pci_host_bridge?

Adding an ops to struct pci_host_bridge?

[Rusty Russell]

Hi,

        On powerpc, we have a possibly-programmable device (CXL) which
we're making look a lot like a PCI bus containing devices.  Rather than
hacking "if (is_really_cxl(dev))" into every powerpc pcibios_* routine,
Ben Herrenschmidt suggested moving from pcibios_* to an ops structure
inside pci_host_bridge.

        In transition, it'd be up to the arch (ie. powerpc) to call
find_pci_host_bridge(dev->bus)->ops->xxx from their pcibios_ functions,
but if there's general interest other archs could start doing it too.

If this seems like a nice idea, we can discuss which pcibios_ functions
make sense to place into ops.

Thanks,
Rusty.