arm64: dts: ti: k3-am64-main: Add OSPI node

AM64 SoC has a single Octal SPI (OSPI) instance under Flash SubSystem
(FSS).  Add DT entry for the same.
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20210318113757.21012-1-vigneshr@ti.com

arch/arm64/boot/dts/ti/k3-am64-main.dtsi

@@ -538,4 +538,29 @@ adc {
 			compatible = "ti,am654-adc", "ti,am3359-adc";
 		};
 	};
+
+	fss: bus@fc00000 {
+		compatible = "simple-bus";
+		reg = <0x00 0x0fc00000 0x00 0x70000>;
+		#address-cells = <2>;
+		#size-cells = <2>;
+		ranges;
+
+		ospi0: spi@fc40000 {
+			compatible = "ti,am654-ospi";
+			reg = <0x00 0x0fc40000 0x00 0x100>,
+			      <0x05 0x00000000 0x01 0x00000000>;
+			interrupts = <GIC_SPI 139 IRQ_TYPE_LEVEL_HIGH>;
+			cdns,fifo-depth = <256>;
+			cdns,fifo-width = <4>;
+			cdns,trigger-address = <0x0>;
+			#address-cells = <0x1>;
+			#size-cells = <0x0>;
+			clocks = <&k3_clks 75 6>;
+			assigned-clocks = <&k3_clks 75 6>;
+			assigned-clock-parents = <&k3_clks 75 7>;
+			assigned-clock-rates = <166666666>;
+			power-domains = <&k3_pds 75 TI_SCI_PD_EXCLUSIVE>;
+		};
+	};
 };