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authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2016-01-12 03:11:14 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2016-01-12 03:11:14 +0300
commit7f4a3702bda0f9f5d34f0241cc81467a55162d7a (patch)
tree085b220efc86abd24fb44d345bbad2dc44f0f7af /Documentation
parenta7da4813429cf36abd042e6da72cc6641767d52f (diff)
parent5ff24d601092b222340b28466e263b1c4559407e (diff)
downloadlinux-7f4a3702bda0f9f5d34f0241cc81467a55162d7a.tar.xz
Merge branch 'pm-opp'
* pm-opp: PM / OPP: Use snprintf() instead of sprintf() PM / OPP: Set cpu_dev->id in cpumask first PM / OPP: Fix parsing of opp-microvolt and opp-microamp properties PM / OPP: Parse 'opp-<prop>-<name>' bindings PM / OPP: Parse 'opp-supported-hw' binding PM / OPP: Add missing doc comments ARM: dts: exynos4412: Rename OPP nodes as opp@<opp-hz> PM / OPP: Rename OPP nodes as opp@<opp-hz> PM / OPP: Remove 'operating-points-names' binding PM / OPP: Add {opp-microvolt|opp-microamp}-<name> binding PM / OPP: Add "opp-supported-hw" binding PM / OPP: Add debugfs support
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/opp/opp.txt132
1 files changed, 93 insertions, 39 deletions
diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index 0cb44dc21f97..601256fe8c0d 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt
@@ -45,21 +45,10 @@ Devices supporting OPPs must set their "operating-points-v2" property with
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
@@ -100,6 +89,14 @@ Optional properties:
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
@@ -112,6 +109,9 @@ Optional properties:
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.
@@ -123,6 +123,26 @@ Optional properties:
- 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.
@@ -157,20 +177,20 @@ 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>;
@@ -236,20 +256,20 @@ independently.
* 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;
@@ -312,20 +332,20 @@ DVFS state 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>;
opp-microamp = <90000>;
@@ -338,20 +358,20 @@ DVFS state together.
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>;
@@ -378,7 +398,7 @@ Example 4: Handling multiple regulators
compatible = "operating-points-v2";
opp-shared;
- opp00 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <970000>, /* Supply 0 */
<960000>, /* Supply 1 */
@@ -391,7 +411,7 @@ Example 4: Handling multiple regulators
/* OR */
- opp00 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <970000 975000 985000>, /* Supply 0 */
<960000 965000 975000>, /* Supply 1 */
@@ -404,7 +424,7 @@ Example 4: Handling multiple regulators
/* OR */
- opp00 {
+ opp@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <970000 975000 985000>, /* Supply 0 */
<960000 965000 975000>, /* Supply 1 */
@@ -417,7 +437,8 @@ Example 4: Handling multiple regulators
};
};
-Example 5: Multiple OPP tables
+Example 5: opp-supported-hw
+(example: three level hierarchy of versions: cuts, substrate and process)
/ {
cpus {
@@ -426,40 +447,73 @@ Example 5: Multiple OPP tables
...
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 */
};
};
};