On Thu, Nov 05, 2015 at 07:11:53AM +0530, Viresh Kumar wrote:
Depending on the version of hardware or its properties, which are only known at runtime, various properties of the OPP can change. For example, an OPP with frequency 1.2 GHz, may have different voltage/current requirements based on the version of the hardware it is running on. Similarly, it may or may not be a turbo or suspend OPP on those circumstances.
In order to not replicate the same OPP tables for varying values of all such fields, this commit introduces the concept of opp-property-<name>. The <name> can be chosen by the platform at runtime, and OPPs will be initialized depending on that name string. Currently support is extended for the following properties:
- opp-microvolt-<name>
- opp-microamp-<name>
- turbo-mode-<name>
- opp-suspend-<name>
If the name string isn't provided by the platform, or if it is provided but doesn't match the properties present in the OPP node, we will fall back to the original properties without the -<name> string, if they are available.
Reviewed-by: Stephen Boyd sboyd@codeaurora.org Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
Documentation/devicetree/bindings/opp/opp.txt | 58 +++++++++++++++++++++++++++ 1 file changed, 58 insertions(+)
diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt index d072fa0ffbd4..61c6f25cf8e2 100644 --- a/Documentation/devicetree/bindings/opp/opp.txt +++ b/Documentation/devicetree/bindings/opp/opp.txt @@ -100,6 +100,14 @@ 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 +120,9 @@ 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.
@@ -120,9 +131,15 @@ 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.
I don't think these last 2 make sense. turbo-mode is a flag that the mode has restrictions such as other cores have to be idle or something. Similarly, opp-suspend should not vary by <name>.
Rob