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

On 3/11/2013 8:23 AM, Jason Gunthorpe wrote:

quoted

(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...

Agreed.  But I was considering that detail to be outside the scope of
this discussion because the same thing must happen for any physical
address at this level of the tree.

Cheers,
Jason