arm64: dts: ti: k3-am654-baseboard: Describe OSPI flash partition info

Describe OSPI flash partition information through device tree, this
helps to remove passing partition information through the mtdparts
commandline parameter which requires maintaining the partition
information in a string format. AM654 baseboard has a MT35XU512ABA
64 MiB OSPI flash with sector size of 128 KiB thus the size of the
smallest partition is chosen as 128 KiB, the partition names and
offsets are chosen according to the corresponding name and offsets
in bootloader.
Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com>
Link: https://lore.kernel.org/r/20230513141712.27346-5-vaishnav.a@ti.comSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>

arch/arm64/boot/dts/ti/k3-am654-base-board.dts

@@ -544,6 +544,52 @@ flash@0 {
 		cdns,tchsh-ns = <60>;
 		cdns,tslch-ns = <60>;
 		cdns,read-delay = <0>;
+
+		partitions {
+			compatible = "fixed-partitions";
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			partition@0 {
+				label = "ospi.tiboot3";
+				reg = <0x0 0x80000>;
+			};
+
+			partition@80000 {
+				label = "ospi.tispl";
+				reg = <0x80000 0x200000>;
+			};
+
+			partition@280000 {
+				label = "ospi.u-boot";
+				reg = <0x280000 0x400000>;
+			};
+
+			partition@680000 {
+				label = "ospi.env";
+				reg = <0x680000 0x20000>;
+			};
+
+			partition@6a0000 {
+				label = "ospi.env.backup";
+				reg = <0x6a0000 0x20000>;
+			};
+
+			partition@6c0000 {
+				label = "ospi.sysfw";
+				reg = <0x6c0000 0x100000>;
+			};
+
+			partition@800000 {
+				label = "ospi.rootfs";
+				reg = <0x800000 0x37c0000>;
+			};
+
+			partition@3fe0000 {
+				label = "ospi.phypattern";
+				reg = <0x3fe0000 0x20000>;
+			};
+		};
 	};
 };