How to activate HSE monitoring

Applicable for STM32MP13x lines

1 Article purpose[edit]

The purpose of this article is to explain how to monitor HSE oscillator.

If HSE oscillator is used in your clock tree, it is possible to enable a monitoring to detect and avoid over frequency. The LPTIM mechanism will detect an over frequency and trig a tamper event which runs some custom actions.

2 How to activate the monitoring[edit]

By default, the HSE monitor is disabled in dtsi "SoC" files.

To activate HSE monitor, add this node in your board OP-TEE device tree

	&hse_monitor {
		status = "okay";