[Skiboot] [PATCH 3/3] ipmi/wdt: Add ipmi watchdog timer support

[Benjamin Herrenschmidt]

On Thu, 2015-01-29 at 09:13 +1100, Stewart Smith wrote:
> > I tend to agree, although at the time Jeremy and I couldn't come up with much 
> > of an alternative. The problem is that we would like the wdt to be activated 
> > before skiboot jumps to the payload so that if the payload fails for some 
> > reason we reboot.
> 
> We could always have the payload enable it *really* early on.. if we
> don't get to the point of being able to make an OPAL call to enable it,
> we're probably unlikely to ever actually boot.

But that's more/less pointless, that means we won't catch possible
transcient issues preventing boot in OPAL itself etc...

In the end, it doesn't matter because the payload is going to be
petitboot kernel which we more/less control and can synchronize with
OPAL, it doesn't remove the fact that subsequently booted OSes may not
do the right thing.

For example on Rhesus, there is no HVC, so we don't get a regular
callback, not a problem in this case since we also don't have the IPMI
watchdog but still...

Cheers,
Ben.