boards/google/dragonclaw/google_dragonclaw.dts

/*
 * Copyright (c) 2022 Google LLC
 *
 * SPDX-License-Identifier: Apache-2.0
 */

/dts-v1/;

#include <st/f4/stm32f412Xg.dtsi>
#include <st/f4/stm32f412c(e-g)ux-pinctrl.dtsi>

/ {
	model = "Google Dragonclaw development board";
	compatible = "google,dragonclaw-fpmcu";

	chosen {
		zephyr,console = &usart2;
		zephyr,shell-uart = &usart2;
		zephyr,sram = &sram0;
		zephyr,flash = &flash0;
		zephyr,flash-controller = &flash;
	};
};

&clk_hsi {
	/* HSI clock frequency is 16MHz */
	status = "okay";
};

&clk_lsi {
	/* LSI clock frequency is 32768kHz */
	status = "okay";
};

&pll {
	div-m = <8>;
	mul-n = <192>; /* 16MHz * 192/8 = 384MHz VCO clock */
	div-p = <4>; /* 96MHz PLL general clock output */
	div-q = <8>; /* 48MHz PLL output for USB, SDIO, RNG */
	div-r = <7>; /* I2S - lowest possible frequency to save power */
	clocks = <&clk_hsi>;
	status = "okay";
};

&rcc {
	clocks = <&pll>; /* Select PLL as SYSCLK source (96MHz) */
	ahb-prescaler = <1>; /* SYSCLK not divided */
	clock-frequency = <DT_FREQ_M(96)>; /* AHB frequency */
	apb1-prescaler = <2>; /* AHB clock divided by 2 */
	apb2-prescaler = <2>; /* AHB clock divided by 2 */
};

/* USART1: AP UART (Host Commands and MKBP) */
&usart1 {
	pinctrl-0 = <&usart1_tx_pa9 &usart1_rx_pa10>;
	pinctrl-names = "default";
	current-speed = <115200>;
	status = "okay";
};

/* USART2: Servo UART (console) */
&usart2 {
	pinctrl-0 = <&usart2_tx_pa2 &usart2_rx_pa3>;
	pinctrl-names = "default";
	current-speed = <115200>;
	status = "okay";
};

/* SPI1: communication with the AP */
&spi1 {
	pinctrl-0 = <&spi1_nss_pa4 &spi1_sck_pa5
		     &spi1_miso_pa6 &spi1_mosi_pa7>;
	pinctrl-names = "default";
	status = "okay";
};

/* SPI2: communication with the fingerprint sensor */
&spi2 {
	pinctrl-0 = <&spi2_nss_pb12 &spi2_sck_pb13
		     &spi2_miso_pb14 &spi2_mosi_pb15>;
	pinctrl-names = "default";
	status = "okay";
};

&rtc {
	clocks = <&rcc STM32_CLOCK_BUS_APB1 0x10000000>,
		 <&rcc STM32_SRC_LSI RTC_SEL(2)>;
	status = "okay";

	backup_regs {
		status = "okay";
	};
};

/*
 * Set flags of unused pins as GPIO_ACTIVE_HIGH (0 << 0), which will be
 * interpreted by GPIO driver as GPIO_DISCONNECTED, without setting the gpio as
 * either input or output. The STM32 GPIO driver will set these pins as analog
 * to reduce power consumption.
 */
&gpiob {
	unused {
		gpio-hog;
		gpios = <2 GPIO_ACTIVE_HIGH>, <5 GPIO_ACTIVE_HIGH>;
	};
};

&gpioc {
	unused {
		gpio-hog;
		gpios = <13 GPIO_ACTIVE_HIGH>, <14 GPIO_ACTIVE_HIGH>,
			<15 GPIO_ACTIVE_HIGH>;
	};
};

&gpioh {
	unused {
		gpio-hog;
		gpios = <0 GPIO_ACTIVE_HIGH>, <1 GPIO_ACTIVE_HIGH>;
	};
};

/*
 * The board uses STM32F412CG in UFQFPN48 package in which gpio[d-g] is not
 * exposed, so disable it.
 */
&gpiod {status = "disabled";};
&gpioe {status = "disabled";};
&gpiof {status = "disabled";};
&gpiog {status = "disabled";};