of/pci: Provide common support for PCI DT parsing

This patchset factors out duplicated code associated with parsing PCI DT "ranges" properties across the architectures and introduces a "ranges" parser. This parser "of_pci_range_parser" can be used directly by ARM host bridge drivers enabling them to obtain ranges from device trees.

I've included the Reviewed-by, Tested-by and Acked-by's received from v5/v6/v7/v8 in this patchset, earlier versions of this patchset (v3) have been tested-by:

Thierry Reding <[email protected]>
Jingoo Han <[email protected]>

I've tested that this patchset builds and runs on ARM and that it builds on PowerPC, x86_64, MIPS and Microblaze.

Compared to the v8 sent by Andrew Murray, the following changes have been made (please note that the MIPS patch is unchanged from v8):

* Remove the unification of pci_process_bridge_OF_ranges between PowerPC and Microblaze. Feedback from Bjorn and Benjamin (along with a NAK) suggested that this goes against their future direction (using more of struct pci_host_bridge and less of arch specific struct pci_controller).

Compared to the v7 sent by Andrew Murray, the following changes have been made (please note that the first patch is unchanged from v7):

* Rename of_pci_range_parser to of_pci_range_parser_init and of_pci_process_ranges to of_pci_range_parser_one as suggested by Grant Likely.

* Reverted back to using a switch statement instead of if/else in pci_process_bridge_OF_ranges. Grant Likely highlighted this change from the original code which was unnecessary.

* Squashed in a patch provided by Gabor Juhos which fixes build errors on MIPS found in the last patchset.

Compared to the v6 sent by Andrew Murray, the following changes have been made in response to build errors/warnings:

* Inclusion of linux/of_address.h in of_pci.c as suggested by Michal Simek to prevent compilation failures on Microblaze (and others) and his ack.

* Use of externs, static inlines and a typo in linux/of_address.h in response to linker errors (multiple defination) on x86_64 as spotted by a kbuild test robot on (jcooper/linux.git mvebu/drivers)

* Add EXPORT_SYMBOL_GPL to of_pci_range_parser function to be consistent with of_pci_process_ranges function

Compared to the v5 sent by Andrew Murray, the following changes have been made:

* Use of CONFIG_64BIT instead of CONFIG_[a32bitarch] as suggested by Rob Herring in drivers/of/of_pci.c

* Added forward declaration of struct pci_controller in linux/of_pci.h to prevent compiler warning as suggested by Thomas Petazzoni

* Improved error checking (!range check), removal of unnecessary be32_to_cpup call, improved formatting of struct of_pci_range_parser layout and replacement of macro with a static inline. All suggested by Rob Herring.

Compared to the v4 (incorrectly labelled v3) sent by Andrew Murray, the following changes have been made:

* Split the patch as suggested by Rob Herring

Compared to the v3 sent by Andrew Murray, the following changes have been made:

* Unify and move duplicate pci_process_bridge_OF_ranges functions to drivers/of/of_pci.c as suggested by Rob Herring

* Fix potential build errors with Microblaze/MIPS

Compared to "[PATCH v5 01/17] of/pci: Provide support for parsing PCI DT ranges property", the following changes have been made:

* Correct use of IORESOURCE_* as suggested by Russell King

* Improved interface and naming as suggested by Thierry Reding

Compared to the v2 sent by Andrew Murray, Thomas Petazzoni did:

* Add a memset() on the struct of_pci_range_iter when starting the for loop in for_each_pci_range(). Otherwise, with an uninitialized of_pci_range_iter, of_pci_process_ranges() may crash.

* Add parenthesis around 'res', 'np' and 'iter' in the for_each_of_pci_range macro definitions. Otherwise, passing something like &foobar as 'res' didn't work.

* Rebased on top of 3.9-rc2, which required fixing a few conflicts in the Microblaze code.

v2:
This follows on from suggestions made by Grant Likely (marc.info/?l=linux-kernel&m=136079602806328)

Andrew Murray (3):
of/pci: Provide support for parsing PCI DT ranges property of/pci: mips: convert to common of_pci_range_parser of/pci: microblaze: convert to common of_pci_range_parser

 arch/microblaze/pci/pci-common.c |  106 ++++++++++++++------------------------
 arch/mips/pci/pci.c              |   50 ++++++-----------
 drivers/of/address.c             |   67 ++++++++++++++++++++++++
 include/linux/of_address.h       |   48 +++++++++++++++++
 4 files changed, 171 insertions(+), 100 deletions(-)