On Thu, 28 Nov 2019 at 19:31, Lorenzo Pieralisi
<lorenzo.pieralisi@xxxxxxx> wrote:
>
> On Thu, Nov 28, 2019 at 06:21:03PM +0100, Ulf Hansson wrote:
> > On Thu, 28 Nov 2019 at 15:15, Lorenzo Pieralisi
> > <lorenzo.pieralisi@xxxxxxx> wrote:
> > >
> > > On Wed, Nov 27, 2019 at 11:29:09AM +0100, Ulf Hansson wrote:
> > >
> > > [...]
> > >
> > > > +struct device *psci_dt_attach_cpu(int cpu)
> > > > +{
> > > > + struct device *dev;
> > > > +
> > > > + /* Currently limit the hierarchical topology to be used in OSI mode. */
> > > > + if (!psci_has_osi_support())
> > > > + return NULL;
> > > > +
> > > > + dev = dev_pm_domain_attach_by_name(get_cpu_device(cpu), "psci");
> > > > + if (IS_ERR_OR_NULL(dev))
> > > > + return dev;
> > > > +
> > > > + pm_runtime_irq_safe(dev);
> > > > + if (cpu_online(cpu))
> > >
> > > It is unclear to me how we handle (or rather we don't) CPU hotplug
> > > with this series - it does not look OK unless genpd code manages
> > > that automatically.
> >
> > The series doesn't handle CPU hotplug at the moment, simply because I
> > am targeting to get the basic support, upstream first.
>
> Basic support must work and that includes CPU hotplug - I don't want
> to merge code that work with assumptions that aren't valid.
>
> > For a functionality point of view, this isn't a problem in my opinion.
> > Simply because the consequence is only that the idle states for the
> > "cluster" will not be reached if there is a CPU brought offline.
> >
> > As we talked about at LPC and as also told Sudeep for the v2 series,
> > CPU hotplug is going to be implemented by using a CPU HP notifier.
>
> Yes, it should be part of the series.
>
> > That should be fine, right?
>
> Yes, hopefully but it has to be part of the series.
Alright, I send a patch on top, asap.
Please review the rest and if it needs a respin, I can fold it into the series.
Kind regards
Uffe
