arm64: dts: add description for solidrun am642 som and evaluation board

Add description for the SolidRun AM642 SoM, and HummingBoard-T
evaluation board.

The SoM features:
- 1x cpsw ethernet with phy
- 2x pru ethernet with phy
- eMMC
- spi flash (assembly option)

Additionally microSD and usb-2.0 otg are included in the SoM
description as they are supported boot sources for the SOC boot-rom.

The Carrier provides:
- 3x RJ45 connector
- 2x M.2 connector
- USB-2.0 Hub
- USB-A Connector
- LEDs
- 2x CAN transceiver
- 1x RS485 transceiver
- sensors

The M.2 connectors support either USB-3.1 or PCI-E depending on status
of a mux. By default the mux is switched off.
Signed-off-by: Josua Mayer <josua@solid-run.com>
Link: https://lore.kernel.org/r/20240219-add-am64-som-v7-3-0e6e95b0a05d@solid-run.comSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>

arch/arm64/boot/dts/ti/Makefile

@@ -40,6 +40,7 @@ dtb-$(CONFIG_ARCH_K3) += k3-am62x-sk-hdmi-audio.dtbo
 # Boards with AM64x SoC
 dtb-$(CONFIG_ARCH_K3) += k3-am642-evm.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am642-evm-icssg1-dualemac.dtbo
+dtb-$(CONFIG_ARCH_K3) += k3-am642-hummingboard-t.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am642-phyboard-electra-rdk.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am642-sk.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am642-tqma64xxl-mbax4xxl.dtb

arch/arm64/boot/dts/ti/k3-am642-hummingboard-t.dts

+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2023 Josua Mayer <josua@solid-run.com>
+ *
+ * DTS for SolidRun AM642 HummingBoard-T,
+ * running on Cortex A53.
+ *
+ */
+
+/dts-v1/;
+
+#include <dt-bindings/leds/common.h>
+#include <dt-bindings/phy/phy.h>
+
+#include "k3-am642.dtsi"
+#include "k3-am642-sr-som.dtsi"
+
+/ {
+	model = "SolidRun AM642 HummingBoard-T";
+	compatible = "solidrun,am642-hummingboard-t", "solidrun,am642-sr-som", "ti,am642";
+
+	aliases {
+		serial5 = &main_uart3;
+	};
+
+	leds {
+		compatible = "gpio-leds";
+		pinctrl-names = "default";
+		pinctrl-0 = <&leds_default_pins>;
+
+		/* D24 */
+		led1: led-1 {
+			label = "led1";
+			gpios = <&main_gpio0 29 GPIO_ACTIVE_HIGH>;
+			color = <LED_COLOR_ID_GREEN>;
+		};
+
+		/* D25 */
+		led2: led-2 {
+			label = "led2";
+			gpios = <&main_gpio0 30 GPIO_ACTIVE_HIGH>;
+			color = <LED_COLOR_ID_GREEN>;
+		};
+
+		/* D26 */
+		led3: led-3 {
+			label = "led3";
+			gpios = <&main_gpio0 33 GPIO_ACTIVE_HIGH>;
+			color = <LED_COLOR_ID_GREEN>;
+		};
+	};
+
+	regulator-m2-3v3 {
+		compatible = "regulator-fixed";
+		pinctrl-names = "default";
+		pinctrl-0 = <&regulator_pcie_3v3_default_pins>;
+		regulator-name = "m2-3v3";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		gpio = <&main_gpio1 17 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+		regulator-always-on;
+	};
+
+	regulator-vpp-1v8 {
+		compatible = "regulator-fixed";
+		pinctrl-names = "default";
+		pinctrl-0 = <&regulator_vpp_1v8_default_pins>;
+		regulator-name = "vpp-1v8";
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <1800000>;
+		gpio = <&main_gpio1 78 GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+	};
+
+	serdes_mux: mux-controller {
+		compatible = "gpio-mux";
+		pinctrl-names = "default";
+		pinctrl-0 = <&serdes_mux_default_pins>;
+		#mux-control-cells = <0>;
+		/*
+		 * Mux has 2 IOs:
+		 * - select: 0 = USB-3 (M2); 1 = PCIE (M1)
+		 * - shutdown: 0 = active; 1 = disabled (high impedance)
+		 */
+		mux-gpios = <&main_gpio1 40 GPIO_ACTIVE_HIGH>, <&main_gpio1 41 GPIO_ACTIVE_HIGH>;
+		/* default disabled */
+		idle-state = <2>;
+	};
+};
+
+&main_gpio0 {
+	m2-reset-hog {
+		gpio-hog;
+		gpios = <12 GPIO_ACTIVE_LOW>;
+		output-low; /* deasserted */
+		line-name = "m2-reset";
+	};
+
+	m1-m2-w-disable1-hog {
+		gpio-hog;
+		gpios = <32 GPIO_ACTIVE_LOW>;
+		output-low; /* deasserted */
+		line-name = "m1-m2-pcie-w-disable1";
+	};
+
+	m1-m2-w-disable2-hog {
+		gpio-hog;
+		gpios = <34 GPIO_ACTIVE_LOW>;
+		output-low; /* deasserted */
+		line-name = "m1-m2-pcie-w-disable2";
+	};
+};
+
+&main_gpio1 {
+	m1-pcie-clkreq0-hog {
+		gpio-hog;
+		gpios = <11 GPIO_ACTIVE_LOW>;
+		input;
+		line-name = "m1-pcie-clkreq0";
+	};
+
+	m2-pcie-clkreq-hog {
+		gpio-hog;
+		gpios = <35 GPIO_ACTIVE_LOW>;
+		input;
+		line-name = "m2-pcie-clkreq";
+	};
+};
+
+&main_i2c0 {
+	pinctrl-0 = <&main_i2c0_default_pins>, <&main_i2c0_int_default_pins>;
+
+	humidity-sensor@41 {
+		compatible = "ti,hdc2010";
+		reg = <0x41>;
+		interrupt-parent = <&main_gpio0>;
+		interrupts = <37 IRQ_TYPE_EDGE_FALLING>;
+	};
+
+	light-sensor@44 {
+		compatible = "ti,opt3001";
+		reg = <0x44>;
+		interrupt-parent = <&main_gpio0>;
+		interrupts = <37 IRQ_TYPE_EDGE_FALLING>;
+	};
+
+	/* charger@6a */
+};
+
+&main_i2c1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&main_i2c1_default_pins>;
+	status = "okay";
+
+	rtc@69 {
+		compatible = "abracon,abx80x";
+		reg = <0x69>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&rtc_int_default_pins>;
+		abracon,tc-diode = "schottky";
+		abracon,tc-resistor = <3>;
+		interrupt-parent = <&main_gpio0>;
+		interrupts = <44 IRQ_TYPE_EDGE_FALLING>;
+	};
+};
+
+&main_mcan0 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&main_mcan0_default_pins>;
+	status = "okay";
+
+	can-transceiver {
+		max-bitrate = <8000000>;
+	};
+};
+
+&main_mcan1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&main_mcan1_default_pins>;
+	status = "okay";
+
+	can-transceiver {
+		max-bitrate = <8000000>;
+	};
+};
+
+&main_pmx0 {
+	leds_default_pins: leds-default-pins {
+		pinctrl-single,pins = <
+			AM64X_IOPAD(0x0074, PIN_OUTPUT, 7) /* GPMC0_AD14.GPIO0_29 */
+			AM64X_IOPAD(0x0078, PIN_OUTPUT, 7) /* GPMC0_AD15.GPIO0_30 */
+			AM64X_IOPAD(0x0088, PIN_OUTPUT, 7) /* GPMC0_OEn_REn.GPIO0_33 */
+		>;
+	};
+
+	main_i2c0_int_default_pins: main-i2c0-int-default-pins {
+		pinctrl-single,pins = <
+			/* external pull-up on Carrier */
+			AM64X_IOPAD(0x0098, PIN_INPUT, 7) /* GPMC0_WAIT0.GPIO0_37 */
+		>;
+	};
+
+	main_i2c1_default_pins: main-i2c1-default-pins {
+		pinctrl-single,pins = <
+			/* external pull-up on SoM */
+			AM64X_IOPAD(0x0268, PIN_INPUT, 0) /* I2C1_SCL.I2C1_SCL */
+			AM64X_IOPAD(0x026c, PIN_INPUT, 0) /* I2C1_SDA.I2C1_SDA */
+		>;
+	};
+
+	main_mcan0_default_pins: main-mcan0-default-pins {
+		pinctrl-single,pins = <
+			AM64X_IOPAD(0x0254, PIN_INPUT, 0) /* MCAN0_RX.MCAN0_RX */
+			AM64X_IOPAD(0x0250, PIN_OUTPUT, 0) /* MCAN0_TX.MCAN0_TX */
+		>;
+	};
+
+	main_mcan1_default_pins: main-mcan1-default-pins {
+		pinctrl-single,pins = <
+			AM64X_IOPAD(0x025c, PIN_INPUT, 0) /* MCAN1_RX.MCAN1_RX */
+			AM64X_IOPAD(0x0258, PIN_OUTPUT, 0) /* MCAN1_TX.MCAN1_TX */
+		>;
+	};
+
+	main_uart3_default_pins: main-uart3-default-pins {
+		pinctrl-single,pins = <
+			AM64X_IOPAD(0x016c, PIN_INPUT, 10) /* PRG0_PRU0_GPO3.UART3_CTSn */
+			AM64X_IOPAD(0x0170, PIN_OUTPUT, 10) /* PRG0_PRU0_GPO4.UART3_TXD */
+			AM64X_IOPAD(0x0174, PIN_OUTPUT, 10) /* PRG0_PRU0_GPO5.UART3_RTSn */
+			AM64X_IOPAD(0x01ac, PIN_INPUT, 10) /* PRG0_PRU0_GPO19.UART3_RXD */
+		>;
+	};
+
+	pcie0_default_pins: pcie0-default-pins {
+		pinctrl-single,pins = <
+			/* connector M2 RESET */
+			AM64X_IOPAD(0x0030, PIN_OUTPUT, 7) /* OSPI0_CSn1.GPIO0_12 */
+			/* connectors M1 & M2 W_DISABLE1 */
+			AM64X_IOPAD(0x0084, PIN_OUTPUT, 7) /* GPMC0_ADVN_ALE.GPIO0_32 */
+			/* connectors M1 & M2 W_DISABLE2 */
+			AM64X_IOPAD(0x008c, PIN_OUTPUT, 7) /* GPMC0_WEN.GPIO0_34 */
+			/* connectors M1 & M2 PERST0 (PCI Reset) */
+			AM64X_IOPAD(0x019c, PIN_OUTPUT, 7) /* PRG0_PRU0_GPO15.GPIO1_15 */
+			/* connector M1 CLKREQ0 */
+			AM64X_IOPAD(0x018c, PIN_INPUT, 7) /* PRG0_PRU0_GPO11.GPIO1_11 */
+			/* connector M2 CLKREQ0 */
+			AM64X_IOPAD(0x01ec, PIN_INPUT, 7) /* PRG0_PRU1_GPO15.GPIO1_35 */
+		>;
+	};
+
+	regulator_pcie_3v3_default_pins: regulator-pcie-3v3-default-pins {
+		pinctrl-single,pins = <
+			AM64X_IOPAD(0x01a4, PIN_OUTPUT, 7) /* PRG0_PRU0_GPO17.GPIO1_17 */
+		>;
+	};
+
+	regulator_vpp_1v8_default_pins: regulator-vpp-1v8-default-pins {
+		pinctrl-single,pins = <
+			AM64X_IOPAD(0x029c, PIN_OUTPUT, 7) /* MMC1_SDWP.GPIO1_78 */
+		>;
+	};
+
+	rtc_int_default_pins: rtc-int-default-pins {
+		pinctrl-single,pins = <
+			/* external pull-up on Carrier */
+			AM64X_IOPAD(0x00b4, PIN_INPUT, 7) /* GPMC0_CSn3.GPIO0_44 */
+		>;
+	};
+
+	serdes_mux_default_pins: serdes-mux-default-pins {
+		pinctrl-single,pins = <
+			/* SEL, 10k pull-down on carrier, 2.2k pullup on SoM */
+			AM64X_IOPAD(0x0200, PIN_OUTPUT, 7) /* PRG0_MDIO0_MDIO.GPIO1_40 */
+			/* EN */
+			AM64X_IOPAD(0x0204, PIN_OUTPUT, 7) /* PRG0_MDIO0_MDC.GPIO1_41 */
+		>;
+	};
+};
+
+&main_uart3 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&main_uart3_default_pins>;
+	uart-has-rtscts;
+	rs485-rts-active-low;
+	linux,rs485-enabled-at-boot-time;
+	status = "okay";
+};
+
+&usb0 {
+	dr_mode = "host";
+};