Configuring WDT causes reboot during FOTA

RE: Configuring WDT causes reboot during FOTA

David — Thu, 16 Feb 2023 00:41:38 GMT

I am using the latest SDK2.2.0 now and still experiencing this same issue where if i use the Hardware WDT and try and perform a FOTA

if i initialize the wdt with no hardware backup

task_wdt_init(NULL);

it works fine but if i add the hardware wdt then as soon as i perform FOTA it crashes as XavierN says.. this quite a big issue, as i have noticed there are certain scenarios where the device can lockup and the task WDTs do not help.. so kind of need to use the hardware WDT and i also need the ability to perform FOTA.. is this in the timeline to get fixed anytime soon?

RE: Configuring WDT causes reboot during FOTA

Susheel Nuguru — Thu, 04 Aug 2022 05:55:20 GMT

[quote user="XavierN"]When you say "toggle a gpio in the watchdog feed function" you mean to modify the "task_wdt_feed" function in task_wdt.c?[/quote]

or pull high a gpio before and low after your application calls task_wdt_feed. Just want to know the timings of this being called before the reset happens.

[quote user="XavierN"]I also observed that the watchdog callback function (which right now it's just a printk) is not bing called while if i just configure the timeout in the wdt short enough for it to trigger it does get called.[/quote]

Dealing with printks on a serial output might be a tricky thing when you are dealing with logs before system would reset. I recommend you to use RTT logging just for testing.

RE: Configuring WDT causes reboot during FOTA

XavierN — Wed, 03 Aug 2022 14:37:38 GMT

When you say "toggle a gpio in the watchdog feed function" you mean to modify the "task_wdt_feed" function in task_wdt.c?

I also observed that the watchdog callback function (which right now it's just a printk) is not bing called while if i just configure the timeout in the wdt short enough for it to trigger it does get called.

Xavier

RE: Configuring WDT causes reboot during FOTA

Susheel Nuguru — Wed, 03 Aug 2022 13:04:01 GMT

I would suggest you to toggle a gpio in the watchdog feed function to see if the feed is happening correctly or if there is a race condition in context switching. Otherwise I do not see why a watchdog that is fed in time should restart.

RE: Configuring WDT causes reboot during FOTA

XavierN — Wed, 03 Aug 2022 12:21:06 GMT

No, it happens always at about 5 seconds regardless of what i set in the watchdog (i have tried from 100ms to 1000000ms)

RE: Configuring WDT causes reboot during FOTA

Susheel Nuguru — Wed, 03 Aug 2022 12:16:47 GMT

[quote user=""]The application works fine but as soon as I try a FOTA update the application reboots after a few seconds, [/quote]

After how many seconds of starting FOTA process is the application rebooting? Is it 100 seconds?

Is it possible that the watchdog feeding thread is starving once the FOTA update process has started?

RE: Configuring WDT causes reboot during FOTA

XavierN — Wed, 03 Aug 2022 10:31:12 GMT

Adding link to this relevant thread: devzone.nordicsemi.com/.../nrf9160-reboot-during-fota-image-download-without-any-crash-information