dt-bindings: net: cdns,macb: Add rx-watermark property

watermark value is the minimum amount of packet data
required to activate the forwarding process. The watermark
implementation and maximum size is dependent on the device
where Cadence MACB/GEM is used.
Signed-off-by: Pranavi Somisetty <pranavi.somisetty@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/cdns,macb.yaml

@@ -109,6 +109,16 @@ properties:
   power-domains:
     maxItems: 1
 
+  cdns,rx-watermark:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      When the receive partial store and forward mode is activated,
+      the receiver will only begin to forward the packet to the external
+      AHB or AXI slave when enough packet data is stored in the SRAM packet buffer.
+      rx-watermark corresponds to the number of SRAM buffer locations,
+      that need to be filled, before the forwarding process is activated.
+      Width of the SRAM is platform dependent, and can be 4, 8 or 16 bytes.
+
   '#address-cells':
     const: 1
 
@@ -166,6 +176,7 @@ examples:
             compatible = "cdns,macb";
             reg = <0xfffc4000 0x4000>;
             interrupts = <21>;
+            cdns,rx-watermark = <0x44>;
             phy-mode = "rmii";
             local-mac-address = [3a 0e 03 04 05 06];
             clock-names = "pclk", "hclk", "tx_clk";