Add the RPMSG bus node along with its GPIO subnodes to the device
tree.

Enable remote device communication and GPIO control via RPMSG on
the i.MX platform.

Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com>
---
 arch/arm64/boot/dts/freescale/imx8ulp.dtsi | 27 ++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx8ulp.dtsi b/arch/arm64/boot/dts/freescale/imx8ulp.dtsi
index 13b01f3aa2a4..93846435c6c1 100644
--- a/arch/arm64/boot/dts/freescale/imx8ulp.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8ulp.dtsi
@@ -191,6 +191,33 @@ scmi_sensor: protocol@15 {
 	cm33: remoteproc-cm33 {
 		compatible = "fsl,imx8ulp-cm33";
 		status = "disabled";
+
+		rpmsg {
+			rpmsg-io-channel {
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				rpmsg_gpioa: gpio@0 {
+					compatible = "rpmsg-gpio";
+					reg = <0>;
+					gpio-controller;
+					#gpio-cells = <2>;
+					#interrupt-cells = <2>;
+					interrupt-controller;
+					interrupt-parent = <&rpmsg_gpioa>;
+				};
+
+				rpmsg_gpiob: gpio@1 {
+					compatible = "rpmsg-gpio";
+					reg = <1>;
+					gpio-controller;
+					#gpio-cells = <2>;
+					#interrupt-cells = <2>;
+					interrupt-controller;
+					interrupt-parent = <&rpmsg_gpiob>;
+				};
+			};
+		};
 	};
 
 	soc: soc@0 {
-- 
2.43.0