arm64: dts: imx8mp: add GPC node with GPU power domains

Add the power domains for the GPUs, which do not require any interaction with
a blk-ctrl, but are simply two PU domains nested inside a MIX domain.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mp.dtsi

@@ -4,6 +4,7 @@
  */
 
 #include <dt-bindings/clock/imx8mp-clock.h>
+#include <dt-bindings/power/imx8mp-power.h>
 #include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/input/input.h>
 #include <dt-bindings/interrupt-controller/arm-gic.h>
@@ -475,6 +476,46 @@ src: reset-controller@30390000 {
 				interrupts = <GIC_SPI 89 IRQ_TYPE_LEVEL_HIGH>;
 				#reset-cells = <1>;
 			};
+
+			gpc: gpc@303a0000 {
+				compatible = "fsl,imx8mp-gpc";
+				reg = <0x303a0000 0x1000>;
+				interrupt-parent = <&gic>;
+				interrupt-controller;
+				#interrupt-cells = <3>;
+
+				pgc {
+					#address-cells = <1>;
+					#size-cells = <0>;
+
+					pgc_gpu2d: power-domain@6 {
+						#power-domain-cells = <0>;
+						reg = <IMX8MP_POWER_DOMAIN_GPU2D>;
+						clocks = <&clk IMX8MP_CLK_GPU2D_ROOT>;
+						power-domains = <&pgc_gpumix>;
+					};
+
+					pgc_gpumix: power-domain@7 {
+						#power-domain-cells = <0>;
+						reg = <IMX8MP_POWER_DOMAIN_GPUMIX>;
+						clocks = <&clk IMX8MP_CLK_GPU_ROOT>,
+							 <&clk IMX8MP_CLK_GPU_AHB>;
+						assigned-clocks = <&clk IMX8MP_CLK_GPU_AXI>,
+								  <&clk IMX8MP_CLK_GPU_AHB>;
+						assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_800M>,
+									 <&clk IMX8MP_SYS_PLL1_800M>;
+						assigned-clock-rates = <800000000>, <400000000>;
+					};
+
+					pgc_gpu3d: power-domain@9 {
+						#power-domain-cells = <0>;
+						reg = <IMX8MP_POWER_DOMAIN_GPU3D>;
+						clocks = <&clk IMX8MP_CLK_GPU3D_ROOT>,
+							 <&clk IMX8MP_CLK_GPU3D_SHADER_CORE>;
+						power-domains = <&pgc_gpumix>;
+					};
+				};
+			};
 		};
 
 		aips2: bus@30400000 {