diff --git a/Documentation/devicetree/bindings/mailbox/fsl,mu.yaml b/Documentation/devicetree/bindings/mailbox/fsl,mu.yaml
index 1a3dff277e2b..675ad9de15bb 100644
--- a/Documentation/devicetree/bindings/mailbox/fsl,mu.yaml
+++ b/Documentation/devicetree/bindings/mailbox/fsl,mu.yaml
@@ -26,6 +26,7 @@ properties:
     oneOf:
       - const: fsl,imx6sx-mu
       - const: fsl,imx7ulp-mu
+      - const: fsl,imx8ulp-mu
       - const: fsl,imx8-mu-scu
       - items:
           - enum: