Devices have inter-dependencies some times. For example a device that
needs to run at 800 MHz, needs another device (e.g. Its power domain) to
be configured at a particular operating performance point.
This patch introduces a new property "required-opp" which can be present
directly in a device's node (if it doesn't need to change its OPPs), or
in device's OPP nodes. More details on the property can be seen in the
binding itself.
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
Documentation/devicetree/bindings/opp/opp.txt | 8 +++
.../devicetree/bindings/power/power_domain.txt | 59 ++++++++++++++++++++++
2 files changed, 67 insertions(+)
diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index a3953a1bb1a1..4e4f30288c8b 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt
@@ -159,6 +159,14 @@ properties.
- status: Marks the node enabled/disabled.
+- required-opp: This contains phandle to an OPP node in another device's OPP
+ table. It may contain an array of phandles, where each phandle points to an
+ OPP of a different device. It should not contain multiple phandles to the OPP
+ nodes in the same OPP table. This specifies the minimum required OPP of the
+ device(s), whose OPP's phandle is present in this property, for the
+ functioning of the current device at the current OPP (where this property is
+ present).
+
Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together.
/ {
diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt
index 61549840ab3b..f824763b202e 100644
--- a/Documentation/devicetree/bindings/power/power_domain.txt
+++ b/Documentation/devicetree/bindings/power/power_domain.txt
@@ -126,4 +126,63 @@ 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".
+Optional properties:
+- required-opp: This contains phandle to an OPP node in another device's OPP
+ table. It may contain an array of phandles, where each phandle points to an
+ OPP of a different device. It should not contain multiple phandles to the OPP
+ nodes in the same OPP table. This specifies the minimum required OPP of the
+ device(s), whose OPP's phandle is present in this property, for the
+ functioning of the current device at the current OPP (where this property is
+ present).
+
+Example:
+- OPP table for domain provider that provides two domains.
+
+ domain0_opp_table: opp_table0 {
+ compatible = "operating-points-v2";
+
+ domain0_opp_0: opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ opp-microvolt = <975000 970000 985000>;
+ };
+ domain0_opp_1: opp-1100000000 {
+ opp-hz = /bits/ 64 <1100000000>;
+ opp-microvolt = <1000000 980000 1010000>;
+ };
+ };
+
+ domain1_opp_table: opp_table1 {
+ compatible = "operating-points-v2";
+
+ domain1_opp_0: opp-1200000000 {
+ opp-hz = /bits/ 64 <1200000000>;
+ opp-microvolt = <975000 970000 985000>;
+ };
+ domain1_opp_1: opp-1300000000 {
+ opp-hz = /bits/ 64 <1300000000>;
+ opp-microvolt = <1000000 980000 1010000>;
+ };
+ };
+
+ parent: power-controller@12340000 {
+ compatible = "foo,power-controller";
+ reg = <0x12340000 0x1000>;
+ #power-domain-cells = <1>;
+ operating-points-v2 = <&domain0_opp_table>, <&domain1_opp_table>;
+ };
+
+ leaky-device0@12350000 {
+ compatible = "foo,i-leak-current";
+ reg = <0x12350000 0x1000>;
+ power-domains = <&parent 0>;
+ required-opp = <&domain0_opp_0>;
+ };
+
+ leaky-device1@12350000 {
+ compatible = "foo,i-leak-current";
+ reg = <0x12350000 0x1000>;
+ power-domains = <&parent 1>;
+ required-opp = <&domain1_opp_1>;
+ };
+
[1]. Documentation/devicetree/bindings/power/domain-idle-state.txt
--
2.15.0.194.g9af6a3dea062
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