arm64: dts: imx8mp: Add NPU Node

The NPU is based on the Vivante GC8000 and its power-domain
is controlled my pgc_mlmix.  Since the power-domain uses
some of these clocks, setup the clock parent and rates
inside the power-domain, and add the NPU node.

The data sheet states the CLK_ML_AHB should be 300MHz for
nominal, but 800MHz clock will divide down to 266 instead.
Boards which operate in over-drive mode should update the
clocks on their boards accordingly.  When the driver loads,
the NPU numerates as:

 etnaviv-gpu 38500000.npu: model: GC8000, revision: 8002
Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

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

@@ -889,6 +889,15 @@ pgc_mlmix: power-domain@24 {
 						clocks = <&clk IMX8MP_CLK_ML_AXI>,
 							 <&clk IMX8MP_CLK_ML_AHB>,
 							 <&clk IMX8MP_CLK_NPU_ROOT>;
+						assigned-clocks = <&clk IMX8MP_CLK_ML_CORE>,
+								  <&clk IMX8MP_CLK_ML_AXI>,
+								  <&clk IMX8MP_CLK_ML_AHB>;
+						assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_800M>,
+									 <&clk IMX8MP_SYS_PLL1_800M>,
+									 <&clk IMX8MP_SYS_PLL1_800M>;
+						assigned-clock-rates = <800000000>,
+								       <800000000>,
+								       <300000000>;
 					};
 				};
 			};
@@ -2014,6 +2023,18 @@ vpumix_blk_ctrl: blk-ctrl@38330000 {
 			interconnect-names = "g1", "g2", "vc8000e";
 		};
 
+		npu: npu@38500000 {
+			compatible = "vivante,gc";
+			reg = <0x38500000 0x200000>;
+			interrupts = <GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&clk IMX8MP_CLK_NPU_ROOT>,
+				 <&clk IMX8MP_CLK_NPU_ROOT>,
+				 <&clk IMX8MP_CLK_ML_AXI>,
+				 <&clk IMX8MP_CLK_ML_AHB>;
+			clock-names = "core", "shader", "bus", "reg";
+			power-domains = <&pgc_mlmix>;
+		};
+
 		gic: interrupt-controller@38800000 {
 			compatible = "arm,gic-v3";
 			reg = <0x38800000 0x10000>,