arm: dts: am642-sk: Add initial sk dts

AM642 StarterKit (SK) board is a low cost, small form factor board
designed for TI’s AM642 SoC. It supports the following interfaces:
* 2 GB LPDDR4 RAM
* x2 Gigabit Ethernet interfaces capable of working in switch and MAC mode
* x1 USB 3.0 Type-A port
* x1 UHS-1 capable µSD card slot
* 2.4/5 GHz WLAN + Bluetooth 4.2 through WL1837
* 512 Mbit OSPI flash
* x2 UART through UART-USB bridge
* XDS110 for onboard JTAG debug using USB
* Temperature sensors, user push buttons and LEDs
* 40-pin Raspberry Pi compatible GPIO header
* 24-pin header for peripherals in MCU island (I2C, UART, SPI, IO)
* 54-pin header for Programmable Realtime Unit (PRU) IO pins
* Interface for remote automation. Includes:
	* power measurement and reset control
	* boot mode change

Add basic support for AM642 SK.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/arch/arm/dts/k3-am642-sk-u-boot.dtsi b/arch/arm/dts/k3-am642-sk-u-boot.dtsi
new file mode 100644
index 0000000..9e170e5
--- /dev/null
+++ b/arch/arm/dts/k3-am642-sk-u-boot.dtsi
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+/ {
+	chosen {
+		stdout-path = "serial2:115200n8";
+		tick-timer = &timer1;
+	};
+};
+
+&cbass_main{
+	u-boot,dm-spl;
+	timer1: timer@2400000 {
+		compatible = "ti,omap5430-timer";
+		reg = <0x0 0x2400000 0x0 0x80>;
+		ti,timer-alwon;
+		clock-frequency = <250000000>;
+		u-boot,dm-spl;
+	};
+};
+
+&main_conf {
+	u-boot,dm-spl;
+	chipid@14 {
+		u-boot,dm-spl;
+	};
+};
+
+&main_pmx0 {
+	u-boot,dm-spl;
+	main_i2c0_pins_default: main-i2c0-pins-default {
+		u-boot,dm-spl;
+		pinctrl-single,pins = <
+			AM64X_IOPAD(0x0260, PIN_INPUT_PULLUP, 0) /* (A18) I2C0_SCL */
+			AM64X_IOPAD(0x0264, PIN_INPUT_PULLUP, 0) /* (B18) I2C0_SDA */
+		>;
+	};
+};
+
+&main_i2c0 {
+	u-boot,dm-spl;
+	pinctrl-names = "default";
+	pinctrl-0 = <&main_i2c0_pins_default>;
+	clock-frequency = <400000>;
+};
+
+&main_uart0 {
+	u-boot,dm-spl;
+};
+
+&dmss {
+	u-boot,dm-spl;
+};
+
+&secure_proxy_main {
+	u-boot,dm-spl;
+};
+
+&dmsc {
+	u-boot,dm-spl;
+};
+
+&k3_pds {
+	u-boot,dm-spl;
+};
+
+&k3_clks {
+	u-boot,dm-spl;
+};
+
+&k3_reset {
+	u-boot,dm-spl;
+};
+
+&sdhci0 {
+	u-boot,dm-spl;
+};
+
+&sdhci1 {
+	u-boot,dm-spl;
+};
+
+&main_mmc1_pins_default {
+	u-boot,dm-spl;
+};