diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
index 75ebc9952a99..7487aa6ef849 100644
--- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
+++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.yaml
@@ -55,6 +55,11 @@ properties:
       - const: pclk
       - const: baud
 
+  fifo-size:
+    description: The fifo size supported by the UART channel.
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [64, 128]
+
 required:
   - compatible
   - reg