Viresh Kumar <viresh.ku...@linaro.org> writes: > Some platforms have the capability to configure the performance state of > PM domains. This patch enhances the genpd core to support such > platforms. > > The performance levels (within the genpd core) are identified by > positive integer values, a lower value represents lower performance > state. > > This patch adds a new genpd API, which is called by user drivers (like > OPP framework): > > - int dev_pm_genpd_set_performance_state(struct device *dev, > unsigned int state); > > This updates the performance state constraint of the device on its PM > domain. On success, the genpd will have its performance state set to a > value which is >= "state" passed to this routine. The genpd core calls > the genpd->set_performance_state() callback, if implemented, > else -ENODEV is returned to the caller. > > The PM domain drivers need to implement the following callback if they > want to support performance states. > > - int (*set_performance_state)(struct generic_pm_domain *genpd, > unsigned int state); > > This is called internally by the genpd core on several occasions. The > genpd core passes the genpd pointer and the aggregate of the > performance states of the devices supported by that genpd to this > callback. This callback must update the performance state of the genpd > (in a platform dependent way). > > The power domains can avoid supplying above callback, if they don't > support setting performance-states. > > Currently we aren't propagating performance state changes of a subdomain > to its masters as we don't have hardware that needs it right now. Over > that, the performance states of subdomain and its masters may not have > one-to-one mapping and would require additional information. We can get > back to this once we have hardware that needs it. > > Tested-by: Rajendra Nayak <rna...@codeaurora.org> > Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
OK, I really like the OPP-related changes suggested by Ulf, and you've removed a lot of the complexity that made it a bit confusing to follow. It's definitley cleaned up and much easier to follow. Thanks for your persistence. This is definitely a needed feature. I have some usecases in mind where the performance state might need to be selected based on OPP voltage, but that's now a change that can be added later when that feature is needed. Reviewed-by: Kevin Hilman <khil...@baylibre.com>
