Re: [PATCH V4 1/9] PM / OPP: Allow OPP table to be used for power-domains

On 20/03/17 09:32, Viresh Kumar wrote: [...]

+Example 7: domain-Performance-state: +(example: For 1GHz require domain state 1 and for 1.1 & 1.2 GHz require state 2)

+/ {

• domain_opp_table: opp_table0 {

• compatible = "operating-points-v2";
  

• opp@1 {
  

• 	domain-performance-state = <1>;
  

• 	opp-microvolt = <975000 970000 985000>;
  

• };
  

• opp@2 {
  

• 	domain-performance-state = <2>;
  

• 	opp-microvolt = <1075000 1000000 1085000>;
  

• };
  

• };
• foo_domain: power-controller@12340000 {

• compatible = "foo,power-controller";
  

• reg = <0x12340000 0x1000>;
  

• #power-domain-cells = <0>;
  

• operating-points-v2 = <&domain_opp_table>;
  

• }
• cpu0_opp_table: opp_table1 {

• compatible = "operating-points-v2";
  

• opp-shared;
  

• opp@1000000000 {
  

• 	opp-hz = /bits/ 64 <1000000000>;
  

• 	domain-performance-state = <1>;
  

• };
  

• opp@1100000000 {
  

• 	opp-hz = /bits/ 64 <1100000000>;
  

• 	domain-performance-state = <2>;
  

• };
  

• opp@1200000000 {
  

• 	opp-hz = /bits/ 64 <1200000000>;
  

• 	domain-performance-state = <2>;
  

• };
  

• };
• cpus {

• #address-cells = <1>;
  

• #size-cells = <0>;
  

• cpu@0 {
  

• 	compatible = "arm,cortex-a9";
  

• 	reg = <0>;
  

• 	clocks = <&clk_controller 0>;
  

• 	clock-names = "cpu";
  

• 	operating-points-v2 = <&cpu0_opp_table>;
  

• 	power-domains = <&foo_domain>;
  

• };
  

• };

+};

Thinking more about this above example, I think you need more explanation. So in the above case you have cpu with clock controller, power-domain and the OPP table info, I can think of few things that need to be explicit:

1. How does the precedence look like ?

2. Since power-domains with OPP table control the performance state, do we ignore clock and operating-points-v2 in the above case completely?

3. Will the power-domain drive the OPP ?