Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

// SPDX-License-Identifier: GPL-2.0
/dts-v1/;
#include "bcm2711.dtsi"
#include "bcm2835-rpi.dtsi"
#include "bcm283x-rpi-usb-peripheral.dtsi"

/ {
	compatible = "raspberrypi,4-model-b", "brcm,bcm2711";
	model = "Raspberry Pi 4 Model B";

	chosen {
		/* 8250 auxiliary UART instead of pl011 */
		stdout-path = "serial1:115200n8";
	};

	/* Will be filled by the bootloader */
	memory@0 {
		device_type = "memory";
		reg = <0 0 0>;
	};

	aliases {
		emmc2bus = &emmc2bus;
		ethernet0 = &genet;
		pcie0 = &pcie0;
	};

	leds {
		act {
			gpios = <&gpio 42 GPIO_ACTIVE_HIGH>;
		};

		pwr {
			label = "PWR";
			gpios = <&expgpio 2 GPIO_ACTIVE_LOW>;
			default-state = "keep";
			linux,default-trigger = "default-on";
		};
	};

	wifi_pwrseq: wifi-pwrseq {
		compatible = "mmc-pwrseq-simple";
		reset-gpios = <&expgpio 1 GPIO_ACTIVE_LOW>;
	};

	sd_io_1v8_reg: sd_io_1v8_reg {
		compatible = "regulator-gpio";
		regulator-name = "vdd-sd-io";
		regulator-min-microvolt = <1800000>;
		regulator-max-microvolt = <3300000>;
		regulator-boot-on;
		regulator-always-on;
		regulator-settling-time-us = <5000>;
		gpios = <&expgpio 4 GPIO_ACTIVE_HIGH>;
		states = <1800000 0x1
			  3300000 0x0>;
		status = "okay";
	};

	sd_vcc_reg: sd_vcc_reg {
		compatible = "regulator-fixed";
		regulator-name = "vcc-sd";
		regulator-min-microvolt = <3300000>;
		regulator-max-microvolt = <3300000>;
		regulator-boot-on;
		enable-active-high;
		gpio = <&expgpio 6 GPIO_ACTIVE_HIGH>;
	};
};

&firmware {
	expgpio: gpio {
		compatible = "raspberrypi,firmware-gpio";
		gpio-controller;
		#gpio-cells = <2>;
		gpio-line-names = "BT_ON",
				  "WL_ON",
				  "PWR_LED_OFF",
				  "GLOBAL_RESET",
				  "VDD_SD_IO_SEL",
				  "CAM_GPIO",
				  "SD_PWR_ON",
				  "";
		status = "okay";
	};
};

&gpio {
	/*
	 * Parts taken from rpi_SCH_4b_4p0_reduced.pdf and
	 * the official GPU firmware DT blob.
	 *
	 * Legend:
	 * "FOO" = GPIO line named "FOO" on the schematic
	 * "FOO_N" = GPIO line named "FOO" on schematic, active low
	 */
	gpio-line-names = "ID_SDA",
			  "ID_SCL",
			  "SDA1",
			  "SCL1",
			  "GPIO_GCLK",
			  "GPIO5",
			  "GPIO6",
			  "SPI_CE1_N",
			  "SPI_CE0_N",
			  "SPI_MISO",
			  "SPI_MOSI",
			  "SPI_SCLK",
			  "GPIO12",
			  "GPIO13",
			  /* Serial port */
			  "TXD1",
			  "RXD1",
			  "GPIO16",
			  "GPIO17",
			  "GPIO18",
			  "GPIO19",
			  "GPIO20",
			  "GPIO21",
			  "GPIO22",
			  "GPIO23",
			  "GPIO24",
			  "GPIO25",
			  "GPIO26",
			  "GPIO27",
			  "RGMII_MDIO",
			  "RGMIO_MDC",
			  /* Used by BT module */
			  "CTS0",
			  "RTS0",
			  "TXD0",
			  "RXD0",
			  /* Used by Wifi */
			  "SD1_CLK",
			  "SD1_CMD",
			  "SD1_DATA0",
			  "SD1_DATA1",
			  "SD1_DATA2",
			  "SD1_DATA3",
			  /* Shared with SPI flash */
			  "PWM0_MISO",
			  "PWM1_MOSI",
			  "STATUS_LED_G_CLK",
			  "SPIFLASH_CE_N",
			  "SDA0",
			  "SCL0",
			  "RGMII_RXCLK",
			  "RGMII_RXCTL",
			  "RGMII_RXD0",
			  "RGMII_RXD1",
			  "RGMII_RXD2",
			  "RGMII_RXD3",
			  "RGMII_TXCLK",
			  "RGMII_TXCTL",
			  "RGMII_TXD0",
			  "RGMII_TXD1",
			  "RGMII_TXD2",
			  "RGMII_TXD3";
};

&pwm1 {
	pinctrl-names = "default";
	pinctrl-0 = <&pwm1_0_gpio40 &pwm1_1_gpio41>;
	status = "okay";
};

/* SDHCI is used to control the SDIO for wireless */
&sdhci {
	#address-cells = <1>;
	#size-cells = <0>;
	pinctrl-names = "default";
	pinctrl-0 = <&emmc_gpio34>;
	bus-width = <4>;
	non-removable;
	mmc-pwrseq = <&wifi_pwrseq>;
	status = "okay";

	brcmf: wifi@1 {
		reg = <1>;
		compatible = "brcm,bcm4329-fmac";
	};
};

/* EMMC2 is used to drive the SD card */
&emmc2 {
	vqmmc-supply = <&sd_io_1v8_reg>;
	vmmc-supply = <&sd_vcc_reg>;
	broken-cd;
	status = "okay";
};

&genet {
	phy-handle = <&phy1>;
	phy-mode = "rgmii-rxid";
	status = "okay";
};

&genet_mdio {
	phy1: ethernet-phy@1 {
		/* No PHY interrupt */
		reg = <0x1>;
	};
};

/* uart0 communicates with the BT module */
&uart0 {
	pinctrl-names = "default";
	pinctrl-0 = <&uart0_ctsrts_gpio30 &uart0_gpio32>;
	uart-has-rtscts;
	status = "okay";

	bluetooth {
		compatible = "brcm,bcm43438-bt";
		max-speed = <2000000>;
		shutdown-gpios = <&expgpio 0 GPIO_ACTIVE_HIGH>;
	};
};

/* uart1 is mapped to the pin header */
&uart1 {
	pinctrl-names = "default";
	pinctrl-0 = <&uart1_gpio14>;
	status = "okay";
};

&vchiq {
	interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
};