[PATCH 24/32] pci: PCIe driver for Marvell Armada 370/XP systems

[Jason Gunthorpe]

> (b) The discovery/enumeration code needs to access config space via
> pci_ops.  The root complex driver implements pci_ops based on a trivial
> parsing of ranges (omitting irrelevant details):
> 
> pci_op_read(devfn, pos) {
>    loop_over_ranges_entries {
>       if (to_devfn(ranges_entry.child) == devfn) {
>          return mmio_read(ranges_entry.parent + pos);
                            ^^^^^^^^^^^^^^^^^^^

This has to be converted through all enclosing node's ranges prior to
being used as a CPU address - the OF core has all the code to do this,
but a new entry point would be needed for this specific application...

Cheers,
Jason