1# SPDX-License-Identifier: GPL-2.0 2%YAML 1.2 3--- 4$id: http://devicetree.org/schemas/power/power-domain.yaml# 5$schema: http://devicetree.org/meta-schemas/core.yaml# 6 7title: Generic PM domains 8 9maintainers: 10 - Rafael J. Wysocki <rjw@rjwysocki.net> 11 - Kevin Hilman <khilman@kernel.org> 12 - Ulf Hansson <ulf.hansson@linaro.org> 13 14description: |+ 15 System on chip designs are often divided into multiple PM domains that can be 16 used for power gating of selected IP blocks for power saving by reduced leakage 17 current. 18 19 This device tree binding can be used to bind PM domain consumer devices with 20 their PM domains provided by PM domain providers. A PM domain provider can be 21 represented by any node in the device tree and can provide one or more PM 22 domains. A consumer node can refer to the provider by a phandle and a set of 23 phandle arguments (so called PM domain specifiers) of length specified by the 24 \#power-domain-cells property in the PM domain provider node. 25 26properties: 27 $nodename: 28 pattern: "^(power-controller|power-domain)([@-].*)?$" 29 30 domain-idle-states: 31 $ref: /schemas/types.yaml#/definitions/phandle-array 32 description: | 33 Phandles of idle states that defines the available states for the 34 power-domain provider. The idle state definitions are compatible with the 35 domain-idle-state bindings, specified in ./domain-idle-state.yaml. 36 37 Note that, the domain-idle-state property reflects the idle states of this 38 PM domain and not the idle states of the devices or sub-domains in the PM 39 domain. Devices and sub-domains have their own idle states independent of 40 the parent domain's idle states. In the absence of this property, the 41 domain would be considered as capable of being powered-on or powered-off. 42 43 operating-points-v2: 44 $ref: /schemas/types.yaml#/definitions/phandle-array 45 description: 46 Phandles to the OPP tables of power domains provided by a power domain 47 provider. If the provider provides a single power domain only or all 48 the power domains provided by the provider have identical OPP tables, 49 then this shall contain a single phandle. Refer to ../opp/opp.txt 50 for more information. 51 52 "#power-domain-cells": 53 description: 54 Number of cells in a PM domain specifier. Typically 0 for nodes 55 representing a single PM domain and 1 for nodes providing multiple PM 56 domains (e.g. power controllers), but can be any value as specified 57 by device tree binding documentation of particular provider. 58 59 power-domains: 60 description: 61 A phandle and PM domain specifier as defined by bindings of the power 62 controller specified by phandle. Some power domains might be powered 63 from another power domain (or have other hardware specific 64 dependencies). For representing such dependency a standard PM domain 65 consumer binding is used. When provided, all domains created 66 by the given provider should be subdomains of the domain specified 67 by this binding. 68 69required: 70 - "#power-domain-cells" 71 72examples: 73 - | 74 power: power-controller@12340000 { 75 compatible = "foo,power-controller"; 76 reg = <0x12340000 0x1000>; 77 #power-domain-cells = <1>; 78 }; 79 80 // The node above defines a power controller that is a PM domain provider and 81 // expects one cell as its phandle argument. 82 83 - | 84 parent2: power-controller@12340000 { 85 compatible = "foo,power-controller"; 86 reg = <0x12340000 0x1000>; 87 #power-domain-cells = <1>; 88 }; 89 90 child2: power-controller@12341000 { 91 compatible = "foo,power-controller"; 92 reg = <0x12341000 0x1000>; 93 power-domains = <&parent2 0>; 94 #power-domain-cells = <1>; 95 }; 96 97 // The nodes above define two power controllers: 'parent' and 'child'. 98 // Domains created by the 'child' power controller are subdomains of '0' power 99 // domain provided by the 'parent' power controller. 100 101 - | 102 parent3: power-controller@12340000 { 103 compatible = "foo,power-controller"; 104 reg = <0x12340000 0x1000>; 105 #power-domain-cells = <0>; 106 domain-idle-states = <&DOMAIN_RET>, <&DOMAIN_PWR_DN>; 107 }; 108 109 child3: power-controller@12341000 { 110 compatible = "foo,power-controller"; 111 reg = <0x12341000 0x1000>; 112 power-domains = <&parent3>; 113 #power-domain-cells = <0>; 114 domain-idle-states = <&DOMAIN_PWR_DN>; 115 }; 116 117 domain-idle-states { 118 DOMAIN_RET: domain-retention { 119 compatible = "domain-idle-state"; 120 entry-latency-us = <1000>; 121 exit-latency-us = <2000>; 122 min-residency-us = <10000>; 123 }; 124 125 DOMAIN_PWR_DN: domain-pwr-dn { 126 compatible = "domain-idle-state"; 127 entry-latency-us = <5000>; 128 exit-latency-us = <8000>; 129 min-residency-us = <7000>; 130 }; 131 }; 132