On Thu, Oct 27, 2016 at 5:46 AM, Viresh Kumar viresh.kumar@linaro.org wrote:
On 26-10-16, 12:00, Kevin Hilman wrote:
Yes. As I've suggested to qcom/linaro folks (off-list discussions), I
No one told me this story :)
think extending genpd to handle performance states is a logical extension. Otherwise, you will be (re)inventing something that looks an awful lot like genpd anyways.
I completely agree. Runtime PM and genpd look to be the perfect placeholder for such stuff. I actually tried to convince Ulf yesterday on this and he wasn't sure if it will ever get accepted upstream and that's when I started this thread :)
The other related framework is per-device PM QoS which could be used to set constraints on specific devices, and the genpd governors would then be responsible for looking at the constraints and changing states as needed.
I am not sure if genpd governors are also background governors like cpufreq, but we need to make sure that the voltage is raised after the function requesting a change returns, so that the clk rate can be increased then.
Well, as I've just written in a message to Kevin, there are reasons why genpd may not be the best place for that.
Thanks, Rafael