Add binding to represent refclk to the PCIe connector.

Signed-off-by: Kishon Vijay Abraham I <redacted>
---
 .../bindings/pci/ti,j721e-pci-host.yaml         | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/ti,j721e-pci-host.yaml b/Documentation/devicetree/bindings/pci/ti,j721e-pci-host.yaml
index 0880a613ece6..7607018a115b 100644
--- a/Documentation/devicetree/bindings/pci/ti,j721e-pci-host.yaml
+++ b/Documentation/devicetree/bindings/pci/ti,j721e-pci-host.yaml

@@ -46,12 +46,21 @@ properties:
     maxItems: 1
 
   clocks:
-    maxItems: 1
-    description: clock-specifier to represent input to the PCIe
+    minItems: 1
+    maxItems: 2
+    description: clock-specifier to represent input to the PCIe for 1 item.
+      2nd item if present represents reference clock to the connector.
 
   clock-names:
-    items:
-      - const: fck
+    oneOf:
+      - description: Represent input clock to the PCIe
+        items:
+          - const: fck
+      - description: Represent input clock to the PCIe and reference clock to
+          the connector.
+        items:
+          - const: fck
+          - const: pcie_refclk