Watchdogs in suspend

Autonomous Machines Jetson & Embedded Systems Jetson TX2
1

Hi all,

Just wanted to ask can anyone clarify if it’s possible to have either the tegra watchdog or the PMIC watchdog expire & cause a reset while the TX2 is in suspend?

Thanks

3

Yes, PMIC is alive during SC7 and PMIC Watchdog is able to recover system if system hangs during SC7 entry or exit.

4

Thanks that’s great news!

I’m having difficultly proving it though. When I open the PMIC watchdog; set it’s timeout to 64; set the system to suspend for 5mins (using the rtcwake feature); the system will suspend for the full five minutes; then a watchdog reset will occur about 60seconds after the system wakes up.

Seems to me like the PMIC’s watchdog isn’t clocking or whatever during suspend - how can I prove it does?

5

hi hannabarbera,
If your system is able to wake up means it was not hang during suspend. so pmic watchdog timeout did not happen. How are you making system hang in suspend state?

6

I just put the system into suspend & have the rtc set up to wake it.

I’d have thought the only way to avoid a watchdog reset after you’ve opened the watchdog is to regulator send the KEEPALIVE signal to the watchdog before it times out. As I’ve no written my test code to do that, and I presume no code was running anywhere in suspend, I’d have thought that was enough to produce a hand & followup reboot. Am I missing something?