Messages in this thread | | | Subject | Re: [RFC/PATCH 0/5] DVFS in the OPP core | From | Rajendra Nayak <> | Date | Fri, 8 Feb 2019 10:09:26 +0530 |
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On 2/8/2019 1:17 AM, Stephen Boyd wrote: > Quoting Rajendra Nayak (2019-02-06 22:57:12) >> >>> 3) How do we handle devices that already have power-domains specified in >>> DT? The opp binding for required-opps doesn't let us specify the power >>> domain to target, instead it assumes that whatever power domain is >>> attached to a device is the one that OPP needs to use to change the >>> genpd performance state. Do we need a >>> dev_pm_opp_set_required_opps_name() or something to be explicit about >>> this? Can we have some way for the power domain that required-opps >>> correspond to be expressed in the OPP tables themselves? >> >> I was converting a few more drivers to use the proposed approach in this >> RFC, in order to identify all outstanding issues we need to deal with, >> and specifically for UFS, I end up with this exact scenario where UFS already >> has an existing power domain (gdsc) and I need to add another one (rpmhpd) for >> setting the performance state. >> >> If I use dev_pm_opp_of_add_table() to add the opp table from DT, the opp >> layer assumes its the same device on which it can do a dev_pm_genpd_set_performance_state() >> with, however the device that's actually associated with the pm_domain when we >> have multiple power domains is infact the one (dummy) that we create when >> the driver makes a call to dev_pm_domain_attach_by_name/id(). >> >> Any thoughts on whats a good way to handle this? >> > > Ulf mentioned that we can use dev_pm_opp_set_genpd_virt_dev() for this. > Does that API work here?
Ah, yes, that should work, I hadn't noticed this API existed.
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