board: phytec: phycore-imx93: Add phyBOARD-Segin-i.MX93 support

Add initial support for the PHYTEC phyBOARD-Segin-i.MX93 board based on
the PHYTEC phyCORE-i.MX93 SoM.

Supported features:
- 1GB LPDDR4 RAM
- eMMC
- external SD
- FEC Ethernet
- debug UART
- watchdog

Signed-off-by: Mathieu Othacehe <othacehe@gnu.org>
Tested-by: Primoz Fiser <primoz.fiser@norik.com>
Reviewed-by: Yannic Moog <y.moog@phytec.de>
diff --git a/arch/arm/dts/imx93-phyboard-segin-u-boot.dtsi b/arch/arm/dts/imx93-phyboard-segin-u-boot.dtsi
new file mode 100644
index 0000000..8bf28c2
--- /dev/null
+++ b/arch/arm/dts/imx93-phyboard-segin-u-boot.dtsi
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (C) 2023 PHYTEC Messtechnik GmbH
+ * Christoph Stoidner <c.stoidner@phytec.de>
+ *
+ * Product homepage:
+ * phyBOARD-Segin carrier board is reused for the i.MX93 design.
+ * https://www.phytec.eu/en/produkte/single-board-computer/phyboard-segin-imx6ul/
+ */
+
+#include "imx93-u-boot.dtsi"
+
+/ {
+	wdt-reboot {
+		compatible = "wdt-reboot";
+		wdt = <&wdog3>;
+		bootph-pre-ram;
+		bootph-some-ram;
+	};
+
+	aliases {
+		ethernet0 = &fec;
+		ethernet1 = &eqos;
+	};
+
+	firmware {
+		optee {
+			compatible = "linaro,optee-tz";
+			method = "smc";
+		};
+	};
+};
+
+&{/soc@0} {
+	bootph-all;
+	bootph-pre-ram;
+};
+
+&aips1 {
+	bootph-pre-ram;
+	bootph-all;
+};
+
+&aips2 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&aips3 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&iomuxc {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&reg_usdhc2_vmmc {
+	u-boot,off-on-delay-us = <20000>;
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&pinctrl_reg_usdhc2_vmmc {
+	bootph-pre-ram;
+};
+
+&pinctrl_uart1 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&pinctrl_usdhc1 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&pinctrl_usdhc2_cd {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&pinctrl_usdhc2_default {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&pinctrl_usdhc2_100mhz {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&pinctrl_usdhc2_200mhz {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&gpio1 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&gpio2 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&gpio3 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&gpio4 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&lpuart1 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&usdhc1 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&usdhc2 {
+	bootph-pre-ram;
+	bootph-some-ram;
+	fsl,signal-voltage-switch-extra-delay-ms = <8>;
+};
+
+&lpi2c1 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&lpi2c2 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&lpi2c3 {
+	bootph-pre-ram;
+	bootph-some-ram;
+};
+
+&s4muap {
+	bootph-pre-ram;
+	bootph-some-ram;
+	status = "okay";
+};
+
+&clk {
+	bootph-all;
+	bootph-pre-ram;
+	/delete-property/ assigned-clocks;
+	/delete-property/ assigned-clock-rates;
+	/delete-property/ assigned-clock-parents;
+};
+
+&osc_32k {
+	bootph-all;
+	bootph-pre-ram;
+};
+
+&osc_24m {
+	bootph-all;
+	bootph-pre-ram;
+};
+
+&clk_ext1 {
+	bootph-all;
+	bootph-pre-ram;
+};
+
+&wdog3 {
+	bootph-all;
+	bootph-pre-ram;
+};
+
+/*
+ * The two nodes below won't be needed once nxp,pca9451a
+ * support is added to the Linux kernel.
+ */
+&iomuxc {
+	pinctrl_lpi2c3: lpi2c3grp {
+		bootph-pre-ram;
+		fsl,pins = <
+			MX93_PAD_GPIO_IO28__LPI2C3_SDA		0x40000b9e
+			MX93_PAD_GPIO_IO29__LPI2C3_SCL		0x40000b9e
+		>;
+	};
+
+	pinctrl_pmic: pmicgrp {
+		bootph-pre-ram;
+		fsl,pins = <
+			MX93_PAD_ENET2_RD3__GPIO4_IO27			0x31e
+		>;
+	};
+};
+
+&lpi2c3 {
+	bootph-pre-ram;
+	bootph-some-ram;
+	clock-frequency = <400000>;
+	pinctrl-names = "default", "sleep";
+	pinctrl-0 = <&pinctrl_lpi2c3>;
+	pinctrl-1 = <&pinctrl_lpi2c3>;
+	status = "okay";
+
+	pmic@25 {
+		bootph-pre-ram;
+		bootph-some-ram;
+		compatible = "nxp,pca9451a";
+		reg = <0x25>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&pinctrl_pmic>;
+		interrupt-parent = <&gpio4>;
+		interrupts = <27 IRQ_TYPE_LEVEL_LOW>;
+
+		regulators {
+			bootph-pre-ram;
+			bootph-some-ram;
+			buck1: BUCK1 {
+				regulator-name = "VDD_SOC";
+				regulator-min-microvolt = <610000>;
+				regulator-max-microvolt = <950000>;
+				regulator-boot-on;
+				regulator-always-on;
+				regulator-ramp-delay = <3125>;
+			};
+
+			buck2: BUCK2 {
+				regulator-name = "VDDQ_0V6";
+				regulator-min-microvolt = <600000>;
+				regulator-max-microvolt = <600000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			buck4: BUCK4 {
+				regulator-name = "VDD_3V3_BUCK";
+				regulator-min-microvolt = <3300000>;
+				regulator-max-microvolt = <3300000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			buck5: BUCK5 {
+				regulator-name = "VDD_1V8";
+				regulator-min-microvolt = <1800000>;
+				regulator-max-microvolt = <1800000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			buck6: BUCK6 {
+				regulator-name = "VDD_1V1";
+				regulator-min-microvolt = <1100000>;
+				regulator-max-microvolt = <1100000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			ldo1: LDO1 {
+				regulator-name = "PMIC_SNVS_1V8";
+				regulator-min-microvolt = <1800000>;
+				regulator-max-microvolt = <1800000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			ldo4: LDO4 {
+				regulator-name = "VDD_0V8";
+				regulator-min-microvolt = <800000>;
+				regulator-max-microvolt = <800000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			ldo5: LDO5 {
+				regulator-name = "NVCC_SD2";
+				regulator-min-microvolt = <1800000>;
+				regulator-max-microvolt = <3300000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+		};
+	};
+};