# Copyright (c) 2021, Linaro ltd
# SPDX-License-Identifier: Apache-2.0

description: STM32 HSE Clock

compatible: "st,stm32-hse-clock"

include: [fixed-clock.yaml]

properties:
  hse-bypass:
    type: boolean
    description: |
      HSE crystal oscillator bypass
      Set to the property to by-pass the oscillator with an external clock.

  css-enabled:
    type: boolean
    description: |
      HSE clock security system enabled
      Set the property to enable the clock security system (CSS) for the HSE clock.

      If a failure is detected on the HSE clock, the HSE oscillator is automatically disabled,
      a clock failure event is sent to timers, and a non-maskable interrupt is generated to
      inform the software about the failure, allowing the MCU to perform rescue operations.
      See the MCU reference manual for details.

      The interaction of CSS and low-power modes is unclear from the documentation.
      For at least some devices Zephyr will reconfigure the clocks on resuming from low-power
      modes; this will include re-enabling CSS. However it is important that you verify
      this for your own hardware.