Kontron SMARC-sAMX8 - Rev. 1.2
www.kontron.com
// 65
2. Check the daemon status as active by giving the below command
# systemctl status watchdog
watchdog.service - watchdog daemon
Loaded: loaded (/lib/systemd/system/watchdog.service; enabled; vendor preset>
Active:
active
(running) since Fri 2019-11-08 08:52:49 UTC; 1min 39s ago
3. Active state implies the daemon has acquired the hardware watchdog and hence the test applications will
not be able to acquire this node
4. Stop the watchdog service by giving the below commands
# systemctl stop watchdog
# systemctl status watchdog
Active:
inactive
(dead) since Fri 2019-11-08 08:55:45 UTC; 7s ago
5. Once the watchdog service is stopped the hardware watchdog is released and hence after that you
should be able to perform the user application tests as per point 3 given in scenario 1 section
Here the actual output of a watchdog command:
Watchdog Dual Stage Test
Note: It is important to make sure the watchdog service is inactive before trying to perform watchdog reset test. Please
refer to the precedent section
Watchdog Reset test
and follow either scenario 1 or 2 depending on your situation.
IMX8 Watchdog supports the Dual stage watchdog along with the Linux Kernel configuration to enable pre-timeout
governor
SMARC SAMX8 BSP enables this configuration by default
Check watchdog pretimeout governor on the sAMX8 board by giving the below command:
=> cat /sys/class/watchdog/watchdog0/pretimeout_governor
panic
The sample user space application is located in the file system path given below. The sample application uses the
IOCTL calls to set the Watchdog
pre-timeout using the
WDIOC_SETPRETIMEOUT
parameter
To test watchdog pre timeout issue the following command. After 3 seconds (timeout - pretimeout), it will indicate a
pretimeout message with kernel panic message and then after 2 seconds, it will reset the board.
=> cd /unit_tests/kontron/watchdog/
=> ./wdt_pretimeout_test.out 5 2 6 0
---- Running < ./wdt_pretimeout_test.out > test ----
