boards: arm: add the Adafruit Grand Central M4 Express

The Adafruit Grand Central M4 Express is an ARM development board
with the form factor of an Arduino Mega.
It features 70 GPIO pins, a microSDHC slot and 8MiB of QSPI Flash.

Signed-off-by: Lukas Jung <lukas.jung@mailbox.org>

boards/arm/adafruit_grand_central_m4_express/Kconfig.board

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+# Adafruit Grand Central M4 Express board configuration
+
+# Copyright (c) 2023 Lukas Jung <lukas.jung@mailbox.org>
+# SPDX-License-Identifier: Apache-2.0
+
+config BOARD_ADAFRUIT_GRAND_CENTRAL_M4_EXPRESS
+	bool "Adafruit Grand Central M4 Express"
+	depends on SOC_PART_NUMBER_SAMD51P20A

boards/arm/adafruit_grand_central_m4_express/Kconfig.defconfig

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+# Adafruit Grand Central M4 Express board configuration
+
+# Copyright (c) 2023 Lukas Jung <lukas.jung@mailbox.org>
+# SPDX-License-Identifier: Apache-2.0
+
+config BOARD
+	default "adafruit_grand_central_m4_express"
+	depends on BOARD_ADAFRUIT_GRAND_CENTRAL_M4_EXPRESS

boards/arm/adafruit_grand_central_m4_express/adafruit_grand_central_m4_express-pinctrl.dtsi

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+/*
+ * Copyright (c) 2023 Lukas Jung <lukas.jung@mailbox.org>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <dt-bindings/pinctrl/samd51p-pinctrl.h>
+
+&pinctrl {
+	sercom0_uart_default: sercom0_uart_default {
+		group1 {
+			pinmux = <PB24C_SERCOM0_PAD0>,
+				 <PB25C_SERCOM0_PAD1>;
+		};
+	};
+
+	sercom2_spi_default: sercom2_spi_default {
+		group1 {
+			pinmux = <PB26C_SERCOM2_PAD0>,
+				 <PB27C_SERCOM2_PAD1>,
+				 <PB29C_SERCOM2_PAD3>;
+		};
+	};
+
+	sercom3_i2c_default: sercom3_i2c_default {
+		group1 {
+			pinmux = <PB20C_SERCOM3_PAD0>,
+				 <PB21C_SERCOM3_PAD1>;
+		};
+	};
+
+	sercom7_spi_default: sercom7_spi_default {
+		group1 {
+			pinmux = <PD8C_SERCOM7_PAD0>,
+				 <PD9C_SERCOM7_PAD1>,
+				 <PD11C_SERCOM7_PAD3>;
+		};
+	};
+
+	usb_dc_default: usb_dc_default {
+		group1 {
+			pinmux = <PA25H_USB_DP>,
+				 <PA24H_USB_DM>;
+		};
+	};
+};

boards/arm/adafruit_grand_central_m4_express/adafruit_grand_central_m4_express.dts

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+/*
+ * Copyright (c) 2023 Lukas Jung <lukas.jung@mailbox.org>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/dts-v1/;
+#include <atmel/samd5xx20.dtsi>
+#include "adafruit_grand_central_m4_express-pinctrl.dtsi"
+
+/ {
+	model = "Adafruit Grand Central M4 Express";
+	compatible = "adafruit,grand-central-m4-express";
+
+	chosen {
+		zephyr,console = &sercom0;
+		zephyr,shell-uart = &sercom0;
+		zephyr,sram = &sram0;
+		zephyr,flash = &flash0;
+		zephyr,code-partition = &code_partition;
+	};
+
+	/* These aliases are provided for compatibility with samples */
+	aliases {
+		led0 = &led0;
+		sdhc0 = &sdhc0;
+	};
+
+	leds {
+		compatible = "gpio-leds";
+		led0: led_0 {
+			gpios = <&portb 1 0>;
+			label = "LED";
+		};
+	};
+};
+
+&cpu0 {
+	clock-frequency = <120000000>;
+};
+
+&sercom0 {
+	status = "okay";
+	compatible = "atmel,sam0-uart";
+	current-speed = <115200>;
+	rxpo = <1>;
+	txpo = <0>;
+
+	pinctrl-0 = <&sercom0_uart_default>;
+	pinctrl-names = "default";
+};
+
+&sercom2 {
+	status = "okay";
+	compatible = "atmel,sam0-spi";
+	dipo = <3>;
+	dopo = <0>;
+
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	pinctrl-0 = <&sercom2_spi_default>;
+	pinctrl-names = "default";
+
+	cs-gpios = <&portb 28 GPIO_ACTIVE_LOW>;
+
+	/* microSD Card */
+	sdhc0: sdhc@0 {
+		status = "okay";
+		compatible = "zephyr,sdhc-spi-slot";
+		reg = <0>;
+		spi-max-frequency = <20000000>;
+		mmc {
+			status = "okay";
+			compatible = "zephyr,sdmmc-disk";
+		};
+	};
+};
+
+&sercom3 {
+	status = "okay";
+	compatible = "atmel,sam0-i2c";
+	clock-frequency = <I2C_BITRATE_FAST>;
+
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	pinctrl-0 = <&sercom3_i2c_default>;
+	pinctrl-names = "default";
+};
+
+&sercom7 {
+	status = "okay";
+	compatible = "atmel,sam0-spi";
+	dipo = <3>;
+	dopo = <0>;
+
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	pinctrl-0 = <&sercom7_spi_default>;
+	pinctrl-names = "default";
+};
+
+zephyr_udc0: &usb0 {
+	status = "okay";
+
+	pinctrl-0 = <&usb_dc_default>;
+	pinctrl-names = "default";
+};
+
+&dmac {
+	status = "okay";
+};
+
+&flash0 {
+	partitions {
+		compatible = "fixed-partitions";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		boot_partition: partition@0 {
+			label = "uf2";
+			reg = <0x00000000 DT_SIZE_K(16)>;
+			read-only;
+		};
+
+		code_partition: partition@4000 {
+			label = "code";
+			reg = <0x4000 DT_SIZE_K(1024-16)>;
+			read-only;
+		};
+	};
+};

boards/arm/adafruit_grand_central_m4_express/adafruit_grand_central_m4_express.yaml

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+identifier: adafruit_grand_central_m4_express
+name: Adafruit Grand Central M4 Express
+type: mcu
+arch: arm
+ram: 256
+flash: 1024
+toolchain:
+  - zephyr
+  - gnuarmemb
+supported:
+  - dma
+  - gpio
+  - i2c
+  - spi
+  - uart
+  - usb_device
+  - watchdog

boards/arm/adafruit_grand_central_m4_express/adafruit_grand_central_m4_express_defconfig

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+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_SOC_SERIES_SAMD51=y
+CONFIG_SOC_PART_NUMBER_SAMD51P20A=y
+CONFIG_BOARD_ADAFRUIT_GRAND_CENTRAL_M4_EXPRESS=y
+CONFIG_SOC_ATMEL_SAMD5X_XOSC32K=y
+CONFIG_SOC_ATMEL_SAMD5X_XOSC32K_AS_MAIN=y
+CONFIG_ARM_MPU=y
+CONFIG_HW_STACK_PROTECTION=y
+CONFIG_CONSOLE=y
+CONFIG_UART_CONSOLE=y
+CONFIG_UART_INTERRUPT_DRIVEN=y
+CONFIG_SERIAL=y
+CONFIG_GPIO=y
+
+CONFIG_BOOTLOADER_BOSSA=y
+CONFIG_BOOTLOADER_BOSSA_ADAFRUIT_UF2=y
+CONFIG_BUILD_OUTPUT_UF2=y
+CONFIG_BUILD_OUTPUT_HEX=y

boards/arm/adafruit_grand_central_m4_express/board.cmake

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+# Copyright (c) 2023 Lukas Jung <lukas.jung@mailbox.org>
+# SPDX-License-Identifier: Apache-2.0
+
+include(${ZEPHYR_BASE}/boards/common/bossac.board.cmake)
+include(${ZEPHYR_BASE}/boards/common/openocd.board.cmake)