[PATCH V7 2/3] OPP: Allow multiple OPP tables to be passed via DT

Stephen Boyd sboyd at codeaurora.org
Fri Jun 19 11:47:47 PDT 2015

On 06/18, Viresh Kumar wrote:
> On 18-06-15, 07:55, Viresh Kumar wrote:
> > Why do you think so? For me the operating-points-v2-names property
> > will be present in CPU node (as there is no OPP node which can have
> > it) and so every CPU is free to choose what it wants to.
> So, I had something like this in mind:
> From: Viresh Kumar <viresh.kumar at linaro.org>
> Date: Thu, 30 Apr 2015 17:38:00 +0530
> Subject: [PATCH] OPP: Allow multiple OPP tables to be passed via DT
> On some platforms (Like Qualcomm's SoCs), it is not decided until
> runtime on what OPPs to use. The OPP tables can be fixed at compile
> time, but which table to use is found out only after reading some efuses
> (sort of an prom) and knowing characteristics of the SoC.
> To support such platform we need to pass multiple OPP tables per device
> and hardware should be able to choose one and only one table out of
> those.
> Update operating-points-v2 bindings to support that.
> Signed-off-by: Viresh Kumar <viresh.kumar at linaro.org>

Looks mostly ok..

> ---
>  Documentation/devicetree/bindings/power/opp.txt | 63 +++++++++++++++++++++++++
>  1 file changed, 63 insertions(+)
> diff --git a/Documentation/devicetree/bindings/power/opp.txt b/Documentation/devicetree/bindings/power/opp.txt
> index 259bf00edf7d..72ccacaac9c9 100644
> --- a/Documentation/devicetree/bindings/power/opp.txt
> +++ b/Documentation/devicetree/bindings/power/opp.txt
> @@ -45,10 +45,21 @@ 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-v2-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-v2-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
> @@ -63,11 +74,16 @@ This describes the OPPs belonging to a device. This node can have following
>    reference an OPP.
>  Optional properties:
> +- opp-name: Name of the OPP table, to uniquely identify it if more than one OPP
> +  table is supplied in "operating-points-v2" property of device.
> +

But isn't this being removed? If it is removed, feel free to add

Reviewed-by: Stephen Boyd <sboyd at codeaurora.org>

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