Re: [PATCH v2 2/4] dt-bindings: arm: Document reboot mode magic

Dmitry Baryshkov
2024-04-16T12:32:14Z

On Tue, 16 Apr 2024 at 12:30, Sudeep Holla <sudeep.holla@arm.com> wrote:
>
> On Sun, Apr 14, 2024 at 12:30:25PM -0700, Elliot Berman wrote:
> > Add bindings to describe vendor-specific reboot modes. Values here
> > correspond to valid parameters to vendor-specific reset types in PSCI
> > SYSTEM_RESET2 call.
> >
>
> IIUC, PSCI SYSTEM_RESET will be always supported, so the choice of using
> SYSTEM_RESET2 sounds like a system policy and must not have any information
> in the device tree. All required support from PSCI is discoverable and
> the policy choice must be userspace driven. That's my opinion.

Well, we are talking about the vendor-specific resets, which are not
discoverable. The spec defines them as "implementation defined".
For example, PCSI spec doesn't define a way to add "reset to
bootloader" or "reset to recovery" kinds of resets.

I think the bindings at least should make it clear that the vendor bit
it being set automatically. I won't comment whether this is a good
decision or not.

--
With best wishes
Dmitry