How to reset the uptime after a reboot?

[vesrup]

Hi,

Is there a way to reset the uptime after doing a reboot? Rebooting the device by resetting the power does reset the uptime, however we need a way to initiate the reboot using firmware.

What we have tried so far:
Using sys_reboot();

Putting in either SYS_REBOOT_COLD or SYS_REBOOT_WARM as arguments in sys_reboot();

NVIC_SystemReset().

Implenenting SYSTEM_TIMER_HAS_DISABLE_SUPPORT in Kconfig, to enable sys_clock_disable();, but then the compiler spits out that sys_clock_disable(); is an undefined reference.

We are using a custom board, with MCU nrf54l15 and NRF Connect SDK 2.9.0.

[vesrup]

Would like to add, that doing the "button" sample and initiating the reboot on the button press, uptime does not in fact reset on the 54l15 DK. It is probably a problem with the 54l15 chip, which we are using on our custom board. Hopefully it will be fixed on the next SDK update.

[Nick Ewalt]

You need to set NRFX_GRTC_CONFIG_CLEAR_AT_INIT. See:

devzone.nordicsemi.com/.../grtc-is-not-cleared-on-reset-causes-zephyr-sys_clock-to-break-when-uptime-20-hours