Hi, On 07/10/2018 03:55 PM, Doug Anderson wrote: > On Tue, Jul 10, 2018 at 3:32 PM, David Collins <collinsd@xxxxxxxxxxxxxx> wrote: >> On 07/10/2018 03:02 PM, Douglas Anderson wrote: >> ... >>> + vdd-s1-supply = <&vph_pwr>; >>> + vdd-s2-supply = <&vph_pwr>; >>> + vdd-s3-supply = <&vph_pwr>; >>> + vdd-s4-supply = <&vph_pwr>; >>> + vdd-s5-supply = <&vph_pwr>; >>> + vdd-s6-supply = <&vph_pwr>; >>> + vdd-s7-supply = <&vph_pwr>; >>> + vdd-s8-supply = <&vph_pwr>; >>> + vdd-s9-supply = <&vph_pwr>; >>> + vdd-s10-supply = <&vph_pwr>; >>> + vdd-s11-supply = <&vph_pwr>; >>> + vdd-s12-supply = <&vph_pwr>; >>> + vdd-s13-supply = <&vph_pwr>; >>> + vdd-l1-l27-supply = <&vreg_s7a_1p025>; >>> + vdd-l2-l8-l17-supply = <&vreg_s3a_1p35>; >>> + vdd-l3-l11-supply = <&vreg_s7a_1p025>; >>> + vdd-l4-l5-supply = <&vreg_s7a_1p025>; >>> + vdd-l6-supply = <&vph_pwr>; >>> + vdd-l7-l12-l14-l15-supply = <&vreg_s5a_2p04>; >>> + vdd-l9-supply = <&vreg_bob>; >>> + vdd-l10-l23-l25-supply = <&vreg_bob>; >>> + vdd-l13-l19-l21-supply = <&vreg_bob>; >>> + vdd-l16-l28-supply = <&vreg_bob>; >>> + vdd-l18-l22-supply = <&vreg_bob>; >>> + vdd-l20-l24-supply = <&vreg_bob>; >>> + vdd-l26-supply = <&vreg_s3a_1p35>; >>> + vin-lvs-1-2-supply = <&vreg_s4a_1p8>; >> >> I would suggest not specifying any of these regulator parent supplies in >> device tree. RPMh will be enforcing all regulator parent-child >> dependencies. Therefore, handling the dependencies in Linux is redundant. >> It will result in additional RPMh requests as well as more time spent in >> regulator framework calls. Overall, it will lead to slightly lower >> performance. Note that while specifying the parent supplies results in >> less efficient runtime behavior, it is not technically wrong so you could >> keep them in place if you prefer. > > Interesting. ...so RPMh will automatically turn on parent regulators > when their children are enabled (assuming that the parent regulator is > also RPMh controlled)? Yes, exactly. RPMh also ensures that the voltage of a parent regulator is sufficient to meet minimum headroom voltage requirements of all subregulated child regulators. > Personally I'd still prefer to see Linux managing its own state and > relying less on RPMh-automatic stuff, but I'd defer to Bjorn / Andy > (or others) to override me. Ok Take care, David -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
