[PATCH v4 4/8] dt-bindings: PCI: dwc: Add dma-ranges, region mask

[Elad Nachman <enachman@marvell.com>]

From: Elad Nachman <enachman@marvell.com>

Add properties to support configurable DMA mask bits and region mask bits:

 1. configurable dma-ranges is needed for Marvell AC5/AC5X SOCs which
    have their physical DDR memory start at address 0x2_0000_0000.

 2. Configurable region mask bits is needed for the Marvell Armada
    7020/7040/8040 SOCs when the DT file places the PCIe window above the 4GB region.
    The Synopsis Designware PCIe IP in these SOCs is too old to specify the
    highest memory location supported by the PCIe, but practically supports
    such locations. Allow these locations to be specified in the DT file.

Signed-off-by: Elad Nachman <enachman@marvell.com>
---
v4:
   1) Fix commit message and its formatting

   2) Replace num-dmamask with dma-ranges

 .../devicetree/bindings/pci/snps,dw-pcie-common.yaml        | 5 +++++
 Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml     | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml b/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml
index d87e13496834..3cb9af1aefeb 100644
--- a/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml
+++ b/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml
@@ -261,6 +261,11 @@ properties:
 
   dma-coherent: true
 
+  num-regionmask:
+    description: |
+      number of region limit mask bits to use, if different than default 32
+    maximum: 64
+
 additionalProperties: true
 
 ...
diff --git a/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml b/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml
index 1a83f0f65f19..ed7ae2a14804 100644
--- a/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml
+++ b/Documentation/devicetree/bindings/pci/snps,dw-pcie.yaml
@@ -197,6 +197,12 @@ properties:
       - contains:
           const: msi
 
+  dma-ranges:
+    description:
+      Defines the DMA mask for devices which due to non-standard HW address
+      assignment have their RAM starting address above the lower 32-bit region.
+      Since this is a mask, only the size attribute of the dma-ranges is used.
+
 additionalProperties: true
 
 required:
-- 
2.17.1