Re: [PATCH 1/6] clk: renesas: r9a06g032: Enable the watchdog reset sources

[Jean-Jacques Hiblot]

Hi Geert,

On 08/02/2022 11:35, Geert Uytterhoeven wrote:
> Hi Jean-Jacques,
>
> On Tue, Feb 8, 2022 at 11:25 AM Jean-Jacques Hiblot
> <jjhiblot@xxxxxxxxxxxxxxx> wrote:
> > On 07/02/2022 16:34, Geert Uytterhoeven wrote:
> > > On Fri, Feb 4, 2022 at 5:18 PM Jean-Jacques Hiblot
> > > <jjhiblot@xxxxxxxxxxxxxxx> wrote:
> > > > The watchdog reset sources are not enabled by default.
> > > > Enabling them here to make sure that the system resets when the watchdog
> > > > timers expire.
> > > >
> > > > Signed-off-by: Jean-Jacques Hiblot <jjhiblot@xxxxxxxxxxxxxxx>
> > > Thanks for your patch!
> > >
> > > R-Car Gen3 and RZ/G2 SoCs have a similar mechanism.
> > > On these SoCs, the boot loader takes care of the configuration, as this
> > > is a system policy that goes beyond the Linux realm.
> > > Perhaps the RZ/N1 boot loader can do the same?
> > >
> > > Gr{oetje,eeting}s,
> > Thanks for you reviews and comments.
> >
> > I'm not conformable with the idea that the safety induced by the
> > watchdog is removed because the bootloader didn't set the register.
> What if the CM33 is the master, and the CM33 just wants to receive an
> interrupt when one of the CA7 watchdog timers times out?

In the next version of the patch I removed the part that enables the 
reset source.

However I kept the part that disables the reset source when the system 
is halted

because the system would otherwise reboot when a watchdog expires. Do you

see a scenario where this could be a problem ?

JJ

> > I'd rather that the kernel is able to enable the watchdog reset source.
> > If it is acceptable, we could use a new DTS entry to force the policy.
> DT describes hardware. not software policy.
> Although I agree e.g. the watchdog timeout value is software policy.

> Gr{oetje,eeting}s,
>
>                          Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                  -- Linus Torvalds