50 lines
1.7 KiB
Plaintext
50 lines
1.7 KiB
Plaintext
|
* Generic PM domains
|
||
|
|
|
||
|
|
System on chip designs are often divided into multiple PM domains that can be
|
||
|
|
used for power gating of selected IP blocks for power saving by reduced leakage
|
||
|
|
current.
|
||
|
|
|
||
|
|
This device tree binding can be used to bind PM domain consumer devices with
|
||
|
|
their PM domains provided by PM domain providers. A PM domain provider can be
|
||
|
|
represented by any node in the device tree and can provide one or more PM
|
||
|
|
domains. A consumer node can refer to the provider by a phandle and a set of
|
||
|
|
phandle arguments (so called PM domain specifiers) of length specified by the
|
||
|
|
#power-domain-cells property in the PM domain provider node.
|
||
|
|
|
||
|
|
==PM domain providers==
|
||
|
|
|
||
|
|
Required properties:
|
||
|
|
- #power-domain-cells : Number of cells in a PM domain specifier;
|
||
|
|
Typically 0 for nodes representing a single PM domain and 1 for nodes
|
||
|
|
providing multiple PM domains (e.g. power controllers), but can be any value
|
||
|
|
as specified by device tree binding documentation of particular provider.
|
||
|
|
|
||
|
|
Example:
|
||
|
|
|
||
|
|
power: power-controller@12340000 {
|
||
|
|
compatible = "foo,power-controller";
|
||
|
|
reg = <0x12340000 0x1000>;
|
||
|
|
#power-domain-cells = <1>;
|
||
|
|
};
|
||
|
|
|
||
|
|
The node above defines a power controller that is a PM domain provider and
|
||
|
|
expects one cell as its phandle argument.
|
||
|
|
|
||
|
|
==PM domain consumers==
|
||
|
|
|
||
|
|
Required properties:
|
||
|
|
- power-domains : A phandle and PM domain specifier as defined by bindings of
|
||
|
|
the power controller specified by phandle.
|
||
|
|
|
||
|
|
Example:
|
||
|
|
|
||
|
|
leaky-device@12350000 {
|
||
|
|
compatible = "foo,i-leak-current";
|
||
|
|
reg = <0x12350000 0x1000>;
|
||
|
|
power-domains = <&power 0>;
|
||
|
|
};
|
||
|
|
|
||
|
|
The node above defines a typical PM domain consumer device, which is located
|
||
|
|
inside a PM domain with index 0 of a power controller represented by a node
|
||
|
|
with the label "power".
|