phandle to a OPP table in their DT node. The OPP core will use this phandle to
find the operating points for the device.
-Devices may want to choose OPP tables at runtime and so can provide a list of
-phandles here. But only *one* of them should be chosen at runtime. This must be
-accompanied by a corresponding "operating-points-names" property, to uniquely
-identify the OPP tables.
-
If required, this can be extended for SoC vendor specfic bindings. Such bindings
should be documented as Documentation/devicetree/bindings/power/<vendor>-opp.txt
and should have a compatible description like: "operating-points-v2-<vendor>".
-Optional properties:
-- operating-points-names: Names of OPP tables (required if multiple OPP
- tables are present), to uniquely identify them. The same list must be present
- for all the CPUs which are sharing clock/voltage rails and hence the OPP
- tables.
-
* OPP Table Node
This describes the OPPs belonging to a device. This node can have following
Entries for multiple regulators must be present in the same order as
regulators are specified in device's DT node.
+- opp-microvolt-<name>: Named opp-microvolt property. This is exactly similar to
+ the above opp-microvolt property, but allows multiple voltage ranges to be
+ provided for the same OPP. At runtime, the platform can pick a <name> and
+ matching opp-microvolt-<name> property will be enabled for all OPPs. If the
+ platform doesn't pick a specific <name> or the <name> doesn't match with any
+ opp-microvolt-<name> properties, then opp-microvolt property shall be used, if
+ present.
+
- opp-microamp: The maximum current drawn by the device in microamperes
considering system specific parameters (such as transients, process, aging,
maximum operating temperature range etc.) as necessary. This may be used to
for few regulators, then this should be marked as zero for them. If it isn't
required for any regulator, then this property need not be present.
+- opp-microamp-<name>: Named opp-microamp property. Similar to
+ opp-microvolt-<name> property, but for microamp instead.
+
- clock-latency-ns: Specifies the maximum possible transition latency (in
nanoseconds) for switching to this OPP from any other OPP.
- opp-suspend: Marks the OPP to be used during device suspend. Only one OPP in
the table should have this.
+- opp-supported-hw: This enables us to select only a subset of OPPs from the
+ larger OPP table, based on what version of the hardware we are running on. We
+ still can't have multiple nodes with the same opp-hz value in OPP table.
+
+ It's an user defined array containing a hierarchy of hardware version numbers,
+ supported by the OPP. For example: a platform with hierarchy of three levels
+ of versions (A, B and C), this field should be like <X Y Z>, where X
+ corresponds to Version hierarchy A, Y corresponds to version hierarchy B and Z
+ corresponds to version hierarchy C.
+
+ Each level of hierarchy is represented by a 32 bit value, and so there can be
+ only 32 different supported version per hierarchy. i.e. 1 bit per version. A
+ value of 0xFFFFFFFF will enable the OPP for all versions for that hierarchy
+ level. And a value of 0x00000000 will disable the OPP completely, and so we
+ never want that to happen.
+
+ If 32 values aren't sufficient for a version hierarchy, than that version
+ hierarchy can be contained in multiple 32 bit values. i.e. <X Y Z1 Z2> in the
+ above example, Z1 & Z2 refer to the version hierarchy Z.
+
- status: Marks the node enabled/disabled.
Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together.
compatible = "operating-points-v2";
opp-shared;
- opp00 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <970000 975000 985000>;
opp-microamp = <70000>;
clock-latency-ns = <300000>;
opp-suspend;
};
- opp01 {
+ opp@1100000000 {
opp-hz = /bits/ 64 <1100000000>;
opp-microvolt = <980000 1000000 1010000>;
opp-microamp = <80000>;
clock-latency-ns = <310000>;
};
- opp02 {
+ opp@1200000000 {
opp-hz = /bits/ 64 <1200000000>;
opp-microvolt = <1025000>;
clock-latency-ns = <290000>;
* independently.
*/
- opp00 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <970000 975000 985000>;
opp-microamp = <70000>;
clock-latency-ns = <300000>;
opp-suspend;
};
- opp01 {
+ opp@1100000000 {
opp-hz = /bits/ 64 <1100000000>;
opp-microvolt = <980000 1000000 1010000>;
opp-microamp = <80000>;
clock-latency-ns = <310000>;
};
- opp02 {
+ opp@1200000000 {
opp-hz = /bits/ 64 <1200000000>;
opp-microvolt = <1025000>;
opp-microamp = <90000;
compatible = "operating-points-v2";
opp-shared;
- opp00 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <970000 975000 985000>;
opp-microamp = <70000>;
clock-latency-ns = <300000>;
opp-suspend;
};
- opp01 {
+ opp@1100000000 {
opp-hz = /bits/ 64 <1100000000>;
opp-microvolt = <980000 1000000 1010000>;
opp-microamp = <80000>;
clock-latency-ns = <310000>;
};
- opp02 {
+ opp@1200000000 {
opp-hz = /bits/ 64 <1200000000>;
opp-microvolt = <1025000>;
opp-microamp = <90000>;
compatible = "operating-points-v2";
opp-shared;
- opp10 {
+ opp@1300000000 {
opp-hz = /bits/ 64 <1300000000>;
opp-microvolt = <1045000 1050000 1055000>;
opp-microamp = <95000>;
clock-latency-ns = <400000>;
opp-suspend;
};
- opp11 {
+ opp@1400000000 {
opp-hz = /bits/ 64 <1400000000>;
opp-microvolt = <1075000>;
opp-microamp = <100000>;
clock-latency-ns = <400000>;
};
- opp12 {
+ opp@1500000000 {
opp-hz = /bits/ 64 <1500000000>;
opp-microvolt = <1010000 1100000 1110000>;
opp-microamp = <95000>;
compatible = "operating-points-v2";
opp-shared;
- opp00 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <970000>, /* Supply 0 */
<960000>, /* Supply 1 */
/* OR */
- opp00 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <970000 975000 985000>, /* Supply 0 */
<960000 965000 975000>, /* Supply 1 */
/* OR */
- opp00 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <970000 975000 985000>, /* Supply 0 */
<960000 965000 975000>, /* Supply 1 */
};
};
-Example 5: Multiple OPP tables
+Example 5: opp-supported-hw
+(example: three level hierarchy of versions: cuts, substrate and process)
/ {
cpus {
...
cpu-supply = <&cpu_supply>
- operating-points-v2 = <&cpu0_opp_table_slow>, <&cpu0_opp_table_fast>;
- operating-points-names = "slow", "fast";
+ operating-points-v2 = <&cpu0_opp_table_slow>;
};
};
- cpu0_opp_table_slow: opp_table_slow {
+ opp_table {
compatible = "operating-points-v2";
status = "okay";
opp-shared;
- opp00 {
+ opp@600000000 {
+ /*
+ * Supports all substrate and process versions for 0xF
+ * cuts, i.e. only first four cuts.
+ */
+ opp-supported-hw = <0xF 0xFFFFFFFF 0xFFFFFFFF>
opp-hz = /bits/ 64 <600000000>;
+ opp-microvolt = <900000 915000 925000>;
...
};
- opp01 {
+ opp@800000000 {
+ /*
+ * Supports:
+ * - cuts: only one, 6th cut (represented by 6th bit).
+ * - substrate: supports 16 different substrate versions
+ * - process: supports 9 different process versions
+ */
+ opp-supported-hw = <0x20 0xff0000ff 0x0000f4f0>
opp-hz = /bits/ 64 <800000000>;
+ opp-microvolt = <900000 915000 925000>;
...
};
};
+};
+
+Example 6: opp-microvolt-<name>, opp-microamp-<name>:
+(example: device with two possible microvolt ranges: slow and fast)
- cpu0_opp_table_fast: opp_table_fast {
+/ {
+ cpus {
+ cpu@0 {
+ compatible = "arm,cortex-a7";
+ ...
+
+ operating-points-v2 = <&cpu0_opp_table>;
+ };
+ };
+
+ cpu0_opp_table: opp_table0 {
compatible = "operating-points-v2";
- status = "okay";
opp-shared;
- opp10 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
- ...
+ opp-microvolt-slow = <900000 915000 925000>;
+ opp-microvolt-fast = <970000 975000 985000>;
+ opp-microamp-slow = <70000>;
+ opp-microamp-fast = <71000>;
};
- opp11 {
- opp-hz = /bits/ 64 <1100000000>;
- ...
+ opp@1200000000 {
+ opp-hz = /bits/ 64 <1200000000>;
+ opp-microvolt-slow = <900000 915000 925000>, /* Supply vcc0 */
+ <910000 925000 935000>; /* Supply vcc1 */
+ opp-microvolt-fast = <970000 975000 985000>, /* Supply vcc0 */
+ <960000 965000 975000>; /* Supply vcc1 */
+ opp-microamp = <70000>; /* Will be used for both slow/fast */
};
};
};