dt-bindings: net: ethernet-controller: Add internal delay properties

Internal Receive and Transmit Clock Delays are a common setting for
RGMII capable devices.

While these delays are typically applied by the PHY, some MACs support
configuring internal clock delay settings, too.  Hence add standardized
properties to configure this.

This is the MAC counterpart of commit 9150069bf5 ("dt-bindings:
net: Add tx and rx internal delays"), which applies to the PHY.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/ethernet-controller.yaml

@@ -120,6 +120,13 @@ properties:
       and is useful for determining certain configuration settings
       such as flow control thresholds.
 
+  rx-internal-delay-ps:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: |
+      RGMII Receive Clock Delay defined in pico seconds.
+      This is used for controllers that have configurable RX internal delays.
+      If this property is present then the MAC applies the RX delay.
+
   sfp:
     $ref: /schemas/types.yaml#definitions/phandle
     description:
@@ -131,6 +138,13 @@ properties:
       The size of the controller\'s transmit fifo in bytes. This
       is used for components that can have configurable fifo sizes.
 
+  tx-internal-delay-ps:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: |
+      RGMII Transmit Clock Delay defined in pico seconds.
+      This is used for controllers that have configurable TX internal delays.
+      If this property is present then the MAC applies the TX delay.
+
   managed:
     description:
       Specifies the PHY management type. If auto is set and fixed-link