of/pci: Add pci_register_io_range() and pci_pio_to_address()

Some architectures do not have a simple view of the PCI I/O space and
instead use a range of CPU addresses that map to bus addresses.  For some
architectures these ranges will be expressed by OF bindings in a device
tree file.

This patch introduces a pci_register_io_range() helper function with a
generic implementation that can be used by such architectures to keep track
of the I/O ranges described by the PCI bindings.  If the PCI_IOBASE macro
is not defined, that signals lack of support for PCI and we return an
error.

In order to retrieve the CPU address associated with an I/O port, a new
helper function pci_pio_to_address() is introduced.  This will search in
the list of ranges registered with pci_register_io_range() and return the
CPU address that corresponds to the given port.

[arnd: add dummy !CONFIG_OF pci_pio_to_address() to fix build errors]
Signed-off-by: Liviu Dudau <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Acked-by: Rob Herring <[email protected]>
CC: Grant Likely <[email protected]>

0 files changed, 0 insertions, 0 deletions