[PATCH v4 2/2] dt: power: st: Provide bindings for ST's OPPs
Viresh Kumar
viresh.kumar at linaro.org
Tue Sep 15 21:33:28 PDT 2015
On 10-09-15, 09:31, Lee Jones wrote:
> I think you answered your own question.
>
> No users == !ABI == Strip it out.
Okay, as I have delayed things enough for you, didn't wanted to do
that anymore. And so worked on it despite very tight schedule :)
Below is the refreshed binding changes (I have split that into 3
patches, but kept the diff here for simplicity).
Other than that, all code changes you need to test your driver are
pushed here:
https://git.linaro.org/people/viresh.kumar/linux.git opp/supported-hw-prop-name-v1
I am not gonna post the patches to the lists, until the time existing
patches get reviewed.
--
viresh
-------------------------8<-------------------------
diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index 719603b87353..b652d0403e93 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
@@ -117,6 +106,14 @@ properties.
Entries for multiple regulators must be present in the same order as their
names are present in 'supply-names' property of the opp-table.
+- 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
@@ -131,6 +128,9 @@ properties.
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.
@@ -139,9 +139,27 @@ properties.
frequency for a short duration of time limited by the device's power, current
and thermal limits.
+- turbo-mode-<name>: Named turbo-mode property. Similar to opp-microvolt-<name>
+ property, but for turbo mode instead.
+
- opp-suspend: Marks the OPP to be used during device suspend. Only one OPP in
the table should have this.
+- opp-suspend-<name>: Named opp-suspend property. Similar to
+ opp-microvolt-<name> property, but for suspend opp instead.
+
+- opp-supported-hw: 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.
+
- status: Marks the node enabled/disabled.
Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together.
@@ -443,7 +461,8 @@ 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 {
@@ -452,40 +471,84 @@ 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 {
+ /*
+ * 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 {
+ /*
+ * 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>, turbo-mode-<name>,
+opp-suspend-<name>:
+(example: device with 2 supplies: vcc0 and vcc1, with two possible ranges: slow
+and fast)
+
+/ {
+ cpus {
+ cpu at 0 {
+ compatible = "arm,cortex-a7";
+ ...
- cpu0_opp_table_fast: opp_table_fast {
+ vcc0-supply = <&cpu_supply0>;
+ vcc1-supply = <&cpu_supply1>;
+ operating-points-v2 = <&cpu0_opp_table>;
+ };
+ };
+
+ cpu0_opp_table: opp_table0 {
compatible = "operating-points-v2";
- status = "okay";
+ supply-names = "vcc0", "vcc1";
opp-shared;
- opp10 {
+ opp00 {
opp-hz = /bits/ 64 <1000000000>;
- ...
+ 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-slow = <70000>;
+ opp-microamp-fast = <71000>;
+ turbo-mode-slow; /* Will marked as turbo only if 'slow' is chosen */
+ opp-suspend-slow; /* Will marked as suspend-opp only if 'slow' is chosen */
};
- opp11 {
- opp-hz = /bits/ 64 <1100000000>;
- ...
+ opp01 {
+ 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 */
+ turbo-mode; /* Always marked as turbo */
+ opp-suspend-fast; /* Will marked as suspend opp only if 'fast' is chosen */
};
};
};
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