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 items: 33 maxItems: 1 34 description: | 35 Phandles of idle states that defines the available states for the 36 power-domain provider. The idle state definitions are compatible with the 37 domain-idle-state bindings, specified in ./domain-idle-state.yaml. 38 39 Note that, the domain-idle-state property reflects the idle states of this 40 PM domain and not the idle states of the devices or sub-domains in the PM 41 domain. Devices and sub-domains have their own idle states independent of 42 the parent domain's idle states. In the absence of this property, the 43 domain would be considered as capable of being powered-on or powered-off. 44 45 operating-points-v2: 46 description: 47 Phandles to the OPP tables of power domains provided by a power domain 48 provider. If the provider provides a single power domain only or all 49 the power domains provided by the provider have identical OPP tables, 50 then this shall contain a single phandle. Refer to ../opp/opp-v2-base.yaml 51 for more information. 52 53 "#power-domain-cells": 54 description: 55 Number of cells in a PM domain specifier. Typically 0 for nodes 56 representing a single PM domain and 1 for nodes providing multiple PM 57 domains (e.g. power controllers), but can be any value as specified 58 by device tree binding documentation of particular provider. 59 60 power-domains: 61 description: 62 A phandle and PM domain specifier as defined by bindings of the power 63 controller specified by phandle. Some power domains might be powered 64 from another power domain (or have other hardware specific 65 dependencies). For representing such dependency a standard PM domain 66 consumer binding is used. When provided, all domains created 67 by the given provider should be subdomains of the domain specified 68 by this binding. 69 70required: 71 - "#power-domain-cells" 72 73additionalProperties: true 74 75examples: 76 - | 77 power: power-controller@12340000 { 78 compatible = "foo,power-controller"; 79 reg = <0x12340000 0x1000>; 80 #power-domain-cells = <1>; 81 }; 82 83 // The node above defines a power controller that is a PM domain provider and 84 // expects one cell as its phandle argument. 85 86 - | 87 parent2: power-controller@12340000 { 88 compatible = "foo,power-controller"; 89 reg = <0x12340000 0x1000>; 90 #power-domain-cells = <1>; 91 }; 92 93 child2: power-controller@12341000 { 94 compatible = "foo,power-controller"; 95 reg = <0x12341000 0x1000>; 96 power-domains = <&parent2 0>; 97 #power-domain-cells = <1>; 98 }; 99 100 // The nodes above define two power controllers: 'parent' and 'child'. 101 // Domains created by the 'child' power controller are subdomains of '0' power 102 // domain provided by the 'parent' power controller. 103 104 - | 105 parent3: power-controller@12340000 { 106 compatible = "foo,power-controller"; 107 reg = <0x12340000 0x1000>; 108 #power-domain-cells = <0>; 109 domain-idle-states = <&DOMAIN_RET>, <&DOMAIN_PWR_DN>; 110 }; 111 112 child3: power-controller@12341000 { 113 compatible = "foo,power-controller"; 114 reg = <0x12341000 0x1000>; 115 power-domains = <&parent3>; 116 #power-domain-cells = <0>; 117 domain-idle-states = <&DOMAIN_PWR_DN>; 118 }; 119 120 domain-idle-states { 121 DOMAIN_RET: domain-retention { 122 compatible = "domain-idle-state"; 123 entry-latency-us = <1000>; 124 exit-latency-us = <2000>; 125 min-residency-us = <10000>; 126 }; 127 128 DOMAIN_PWR_DN: domain-pwr-dn { 129 compatible = "domain-idle-state"; 130 entry-latency-us = <5000>; 131 exit-latency-us = <8000>; 132 min-residency-us = <7000>; 133 }; 134 }; 135