1 # SPDX-License-Identifier: GPL-2.0
4 $id: http://devicetree.org/schemas/power/power-domain.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 title: Generic PM domains
10 - Rafael J. Wysocki <rjw@rjwysocki.net>
11 - Kevin Hilman <khilman@kernel.org>
12 - Ulf Hansson <ulf.hansson@linaro.org>
15 System on chip designs are often divided into multiple PM domains that can be
16 used for power gating of selected IP blocks for power saving by reduced leakage
19 This device tree binding can be used to bind PM domain consumer devices with
20 their PM domains provided by PM domain providers. A PM domain provider can be
21 represented by any node in the device tree and can provide one or more PM
22 domains. A consumer node can refer to the provider by a phandle and a set of
23 phandle arguments (so called PM domain specifiers) of length specified by the
24 \#power-domain-cells property in the PM domain provider node.
28 pattern: "^(power-controller|power-domain)([@-].*)?$"
31 $ref: /schemas/types.yaml#/definitions/phandle-array
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.
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.
46 $ref: /schemas/types.yaml#/definitions/phandle-array
50 Phandles to the OPP tables of power domains provided by a power domain
51 provider. If the provider provides a single power domain only or all
52 the power domains provided by the provider have identical OPP tables,
53 then this shall contain a single phandle. Refer to ../opp/opp-v2-base.yaml
56 "#power-domain-cells":
58 Number of cells in a PM domain specifier. Typically 0 for nodes
59 representing a single PM domain and 1 for nodes providing multiple PM
60 domains (e.g. power controllers), but can be any value as specified
61 by device tree binding documentation of particular provider.
65 A phandle and PM domain specifier as defined by bindings of the power
66 controller specified by phandle. Some power domains might be powered
67 from another power domain (or have other hardware specific
68 dependencies). For representing such dependency a standard PM domain
69 consumer binding is used. When provided, all domains created
70 by the given provider should be subdomains of the domain specified
74 - "#power-domain-cells"
76 additionalProperties: true
80 power: power-controller@12340000 {
81 compatible = "foo,power-controller";
82 reg = <0x12340000 0x1000>;
83 #power-domain-cells = <1>;
86 // The node above defines a power controller that is a PM domain provider and
87 // expects one cell as its phandle argument.
90 parent2: power-controller@12340000 {
91 compatible = "foo,power-controller";
92 reg = <0x12340000 0x1000>;
93 #power-domain-cells = <1>;
96 child2: power-controller@12341000 {
97 compatible = "foo,power-controller";
98 reg = <0x12341000 0x1000>;
99 power-domains = <&parent2 0>;
100 #power-domain-cells = <1>;
103 // The nodes above define two power controllers: 'parent' and 'child'.
104 // Domains created by the 'child' power controller are subdomains of '0' power
105 // domain provided by the 'parent' power controller.
108 parent3: power-controller@12340000 {
109 compatible = "foo,power-controller";
110 reg = <0x12340000 0x1000>;
111 #power-domain-cells = <0>;
112 domain-idle-states = <&DOMAIN_RET>, <&DOMAIN_PWR_DN>;
115 child3: power-controller@12341000 {
116 compatible = "foo,power-controller";
117 reg = <0x12341000 0x1000>;
118 power-domains = <&parent3>;
119 #power-domain-cells = <0>;
120 domain-idle-states = <&DOMAIN_PWR_DN>;
124 DOMAIN_RET: domain-retention {
125 compatible = "domain-idle-state";
126 entry-latency-us = <1000>;
127 exit-latency-us = <2000>;
128 min-residency-us = <10000>;
131 DOMAIN_PWR_DN: domain-pwr-dn {
132 compatible = "domain-idle-state";
133 entry-latency-us = <5000>;
134 exit-latency-us = <8000>;
135 min-residency-us = <7000>;