Hi Heinrich, Le jeu. 4 nov. 2021 à 12:45, Heinrich Schuchardt < heinrich.schucha...@canonical.com> a écrit :
> On 11/4/21 10:55, François Ozog wrote: > > Hi Heinrich, > > > > On Thu, 4 Nov 2021 at 10:31, Heinrich Schuchardt > > <heinrich.schucha...@canonical.com > > <mailto:heinrich.schucha...@canonical.com>> wrote: > > > > The watchdog system reset driver can reboot the device but it cannot > > power > > it off. If power off is requested, the driver should not reset the > > system > > but leave powering off to one of the other system reset drivers. > > > > As power cycling is typically not a feature of a watchdog driver the > > reset > > types SYSRESET_POWER and SYSRESET_POWER_OFF shall both be excluded. > > > > A candid question here. I know that IPMI can powercycle a platform. > > How would we handle that should there be a way to make the power cycle > > happen? > > (for instance we could define a PSCI extension of SYSTEM_RESET2 to have > > a power cycle effect) > > Your comment seems not to relate to the validity of the current patch. > yes. It was a related question to understand more about the topic. > > For PSCI we have a separate sysreset driver > drivers/sysreset/sysreset_psci.c. That driver currently does not support > SYSRESET_POWER. > > Once such an extension is offered by PSCI you should define a > device-tree node property for it in Linux' > Documentation/devicetree/bindings/arm/psci.yaml. Next implement a probe > function in the driver code to detect that property. In > psci_sysreset_request(), if type=SYSRESET_POWER, call the appropriate > PSCI method if the extension is enabled or return -ENOSYS if the > extension is not available. > > Currently in U-Boot I see no code invoking a reset with SYSRESET_POWER. > You would have to change function do_reset() in > drivers/sysreset/sysreset-uclass.c to accept a new argument to select > this reset type. > > Best regards > > Heinrich > -- François-Frédéric Ozog | *Director Business Development* T: +33.67221.6485 francois.o...@linaro.org | Skype: ffozog
