If the consumers don't need the capability of switching to different
domain performance states at runtime, then they can simply define their
required domain performance state in their nodes directly.
But if the device needs the capability of switching to different domain
performance states, as they may need to support different clock rates,
then the per OPP node can be used to contain that information.
This patch introduces the domain-performance-state (already defined by
Power Domain bindings) to the per OPP node.
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Tested-by: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx>
---
Documentation/devicetree/bindings/opp/opp.txt | 64 +++++++++++++++++++++++++++
1 file changed, 64 insertions(+)
diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index 9f5ca4457b5f..7f6bb52521b6 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt
@@ -154,6 +154,15 @@ properties.
- status: Marks the node enabled/disabled.
+- domain-performance-state: A positive integer value representing the minimum
+ performance level (of the parent domain) required by the consumer as defined
+ by ../power/power_domain.txt binding document. The OPP nodes can contain the
+ "domain-performance-state" property, only if the device node contains a
+ "power-domains" property. The OPP nodes aren't allowed to contain the
+ "domain-performance-state" property partially, i.e. Either all OPP nodes in
+ the OPP table have the "domain-performance-state" property or none of them
+ have it.
+
Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together.
/ {
@@ -528,3 +537,58 @@ Example 5: opp-supported-hw
};
};
};
+
+Example 7: domain-Performance-state:
+(example: For 1GHz require domain state 1 and for 1.1 & 1.2 GHz require state 2)
+
+/ {
+ cpu0_opp_table: opp_table0 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp@1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ domain-performance-state = <1>;
+ };
+ opp@1100000000 {
+ opp-hz = /bits/ 64 <1100000000>;
+ domain-performance-state = <2>;
+ };
+ opp@1200000000 {
+ opp-hz = /bits/ 64 <1200000000>;
+ domain-performance-state = <2>;
+ };
+ };
+
+ foo_domain: power-controller@12340000 {
+ compatible = "foo,power-controller";
+ reg = <0x12340000 0x1000>;
+ #power-domain-cells = <0>;
+
+ performance-states {
+ compatible = "domain-performance-state";
+ pstate@1 {
+ reg = <1>;
+ domain-microvolt = <970000 975000 985000>;
+ };
+ pstate@2 {
+ reg = <2>;
+ domain-microvolt = <1000000 1075000 1085000>;
+ };
+ };
+ }
+
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ compatible = "arm,cortex-a9";
+ reg = <0>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ operating-points-v2 = <&cpu0_opp_table>;
+ power-domains = <&foo_domain>;
+ };
+ };
+};
--
2.7.1.410.g6faf27b
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
