zephyr/boards/arm/stm32f412g_disco/stm32f412g_disco_defconfig

CONFIG_ARM=y
CONFIG_BOARD_STM32F412G_DISCO=y
CONFIG_SOC_SERIES_STM32F4X=y
CONFIG_SOC_STM32F412ZG=y
# 100MHz system clock (highest value to get a precise USB clock should be 96MHz)
CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC=100000000
CONFIG_SYS_CLOCK_TICKS_PER_SEC=1000

# Enable MPU
CONFIG_STM32_ARM_MPU_ENABLE=y

# enable USART2 - passthrough to STLINK v2 connector
CONFIG_UART_STM32_PORT_2=y

# enable pinmux
CONFIG_PINMUX=y

# enable GPIO ports A, B, C, D, E
CONFIG_GPIO=y
CONFIG_GPIO_STM32_PORTE=y

# clock configuration
CONFIG_CLOCK_CONTROL=y

# Clock configuration for Cube Clock control driver
CONFIG_CLOCK_STM32_HSE_CLOCK=8000000
CONFIG_CLOCK_STM32_SYSCLK_SRC_PLL=y
# use HSE as PLL input
CONFIG_CLOCK_STM32_PLL_SRC_HSE=y
# however, the board does not have an external oscillator, so just use
# the 8MHz clock signal coming from integrated STLink
CONFIG_CLOCK_STM32_HSE_BYPASS=y
# produce 100MHz clock at PLL output
CONFIG_CLOCK_STM32_PLL_M_DIVISOR=4
CONFIG_CLOCK_STM32_PLL_N_MULTIPLIER=100
CONFIG_CLOCK_STM32_PLL_P_DIVISOR=2
CONFIG_CLOCK_STM32_PLL_Q_DIVISOR=8
CONFIG_CLOCK_STM32_AHB_PRESCALER=1
CONFIG_CLOCK_STM32_APB1_PRESCALER=2
CONFIG_CLOCK_STM32_APB2_PRESCALER=1