diff --git a/arch/arm/dts/uniphier-ph1-ld20-ref.dts b/arch/arm/dts/uniphier-ph1-ld20-ref.dts
index 108adeb..1af2ebe 100644
--- a/arch/arm/dts/uniphier-ph1-ld20-ref.dts
+++ b/arch/arm/dts/uniphier-ph1-ld20-ref.dts
@@ -8,6 +8,7 @@
 
 /dts-v1/;
 /include/ "uniphier-ph1-ld20.dtsi"
+/include/ "uniphier-ref-daughter.dtsi"
 /include/ "uniphier-support-card.dtsi"
 
 / {