[RFC v3 11/25] watchdog: renesas_wdt: Add R-Car Gen2 support

[Fabrizio Castro]

Hello Guenter, Geert

thank you for your feedback!

> >
> > IIRC, the reason we don't have the restart callback on R-Car Gen3 is the
> > arm64 maintainers insisting on using PSCI, and vetoing other means,
> > to restart the system.
> >
>
> You could just give it lower priority than PSCI.

I am looking at the implementation of machine_restart() for both arm and arm64,
and it looks like that if arm_pm_restart gets set, then arm_pm_restart has the
highest priority of all. If arm_pm_restart is not set, then the kernel will go through
the restart_handler_list, and the registered priority for the restart method will matter
at that point.
My understanding is that Gen3 does set arm_pm_restart due to
drivers/firmware/psci.c, and therefore other restart handlers shouldn't matter too
much, but I am not familiar with Gen3 at all.
Shall I just set the restart priority to 128 and leave the callback in place for both Gen2
and Gen3?

Thanks,
Fab

>
> > Which leaves us with a few boards where we have to use the watchdog, and
> > wait until the timeout triggers...
> >
>
> Which means the veto is counter-productive and thus meaningless.
>
> Guenter
>



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