They’re described in paragraph 6.6 of the PRM itself.
On Toradex KB I find this article that doesn’t refer to the Plus (i.MX 8M Mini is there).
And so I suppose one of the watchdog timers is (can be) used by Linux that runs on Cortex-A (A53).
is this watchdog timer used by TorizonOS?
which is the timer used for Linux (WDOG1, WDOG2 or WDOG3)?
in PRM I see that pin B6 (GPIO1_IO02) can be configured to be triggered for WDOG1_WDOG_ANY or WDOG1_WDOG_B. Is this pin available on Verdin X1 connector? It doesn’t seem so from the datasheet, but I need a confirmation.
In my project I use Cortex-M too and so I need to use a dedicated watchdog for it.
The wdog example from NXP SDK uses WDOG3 for Cortex-M.
Can I use it on Verdin SoM too?
Does this resets Cortex-M only?
Is the Cortex-M firmware preserved? Or should the Cortex-A take care of reloading it?
I would assume yes, the standard device-trees remain the same in Torizon
in PRM I see that pin B6 (GPIO1_IO02) can be configured to be triggered for WDOG1_WDOG_ANY or WDOG1_WDOG_B. Is this pin available on Verdin X1 connector? It doesn’t seem so from the datasheet, but I need a confirmation.
The extra flag fsl,ext-reset-output; on the watchdog device-tree node means that the watchdog will not generate a software reset, but will instead assert the WDOG_B pin. This pin is not available on the edge connector, it’s connected to the PMIC.
Can I use it on Verdin SoM too?
Does this resets Cortex-M only?
As you can see on the RM, there are options to configure WDOG3 to either reset only the M7 or the full system:
Is the Cortex-M firmware preserved? Or should the Cortex-A take care of reloading it?
I think this would need to be tested and I imagine it could also depend on which memory you’re linking your M7 code to. If resetting only the M7 core, I would think the memories (like TCM) should not be reset with it because the entire chip is not going through a reset. So it could be that the M7 would just start running as if the firmware was on flash. The NXP WDOG example you pointed seems to also point in this direction.
