support mapping PCI device ids to stream ids for MSIs

From: Stuart Yoder <[email protected]>

A binding for PCI nodes has been finalized specifying how PCI device IDs can be mapped to MSI specifiers. See Documentation/devicetree/bindings/pci/pci-msi.txt in the kernel.

For ls2080a and similar Layerscape SoCs, the MSI specifier is the stream id. A programmable table (LUT) in the PCI controller defines the hardware mapping of PCI requester IDs to stream IDs.

This patch series implements support for this mapping.

Version 6 of the series squashes patches 4-7 together to avoid static functions defined but not used. This results in 5 patches:

Patch 1 removes the obsolete available-stream-id support. Patch 2 updates stream ID partitioning info to be current Patch 3 updates pci.h so pci_get_hose_head() is available Patch 4 defines LUT register offsets
Patch 5 implements a function to iterate over all PCI buses
and set up a LUT entry and msi-map for all discovered devices. Helper functions allocate LUT entries, streamIDs, and append msi-map entries.

This patch series enables MSIs on ls2080a on v4.5-rc5 and later kernels. The obsolete support removed was unused in any upstream kernels.

-v2 changes
-in patch 7 removed skip of the host bridge when scanning the
bus
-v3 changes
-patch 4: moved LUT #defines to immap_lsch3.h, made index
allocator return an int
-patch 5: return 0xffffffff on error
-patch 7: fixed return value checks
-v4 changes
-put all device ID to stream ID mapping under LS2 #ifdefs
-v5 changes
-check CONFIG_FSL_LSCH3 instead of SoC specific defines
-v6 changes
-squashed patches 4-7 together, split out LUT #defines
into separate patch, replaced a remaining SoC define with CONFIG_FSL_LSCH3

Stuart Yoder (5):
armv8: ls2080a: remove obsolete stream ID partitioning support
armv8: ls2080a: update stream ID partitioning info
pci: make pci_get_hose_head() available to external users pci/layerscape: add defines for LUT
pci/layerscape: set LUT and msi-map for discovered PCI devices

 arch/arm/cpu/armv8/fsl-layerscape/fdt.c            |  113 ----------
 .../include/asm/arch-fsl-layerscape/immap_lsch3.h  |    4 +
 .../asm/arch-fsl-layerscape/ls2080a_stream_id.h    |   55 +++--
 drivers/pci/pcie_layerscape.c                      |  217 +++++++++++++-------
 include/pci.h                                      |    1 +
 5 files changed, 186 insertions(+), 204 deletions(-)

1.7.9.5