Re: [RFC PATCH] dt-bindings: opp: Extend qcom-opp bindings with properties needed for CPR

From: Viresh Kumar
Date: Mon Oct 22 2018 - 01:46:00 EST


On 15-10-18, 14:47, Niklas Cassel wrote:
> Extend qcom-opp bindings with properties needed for Core Power Reduction
> (CPR).
>
> CPR is included in a great variety of Qualcomm SoC, e.g. msm8916 and
> msm8996, and was first introduced in msm8974.
>
> Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
> ---
> Hello Rob, Rajendra,
>
> Sorry for not replying sooner.
> Since Rob wanted the binding to be complete before merging,
> this is my proposal to extend the OPP binding with properties
> needed to support CPR (both for msm8916 and msm8996).
> I've discussed the proposal with Viresh, and this proposal
> seems better than what I previously suggested here:
> https://lore.kernel.org/lkml/20181005204424.GA29500@xxxxxxxxxxxx/
>
> .../devicetree/bindings/opp/qcom-opp.txt | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/opp/qcom-opp.txt b/Documentation/devicetree/bindings/opp/qcom-opp.txt
> index db4d970c7ec7..3ab5dd84de86 100644
> --- a/Documentation/devicetree/bindings/opp/qcom-opp.txt
> +++ b/Documentation/devicetree/bindings/opp/qcom-opp.txt
> @@ -23,3 +23,22 @@ Required properties:
> representing a corner/level that's communicated with a remote microprocessor
> (usually called the RPM) which then translates it into a certain voltage on
> a voltage rail.
> +
> +Optional properties:
> +- opp-hz: Frequency in Hz, expressed as a 64-bit big-endian integer. Even
> + though a power domain doesn't need a opp-hz, there can be devices in the
> + power domain that need to know the highest supported frequency for each
> + corner/level (e.g. CPR), in order to properly initialize the hardware.
> +
> +- qcom,fuse-level: A positive value representing the fuse corner/level
> + associated with this OPP node. Sometimes several corners/levels shares
> + a certain fuse corner/level. A fuse corner/level contains e.g. ref uV,
> + min uV, and max uV.
> +
> +- qcom,fuse-level-<name>: Named qcom,fuse-level property. This is exactly
> + similar to the above qcom,fuse-level property, but allows multiple
> + fuse corners/levels to be provided for the same OPP. At runtime, the
> + platform can pick a <name> and matching qcom,fuse-level-<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 qcom,fuse-level-<name>
> + properties, then qcom,fuse-level property shall be used, if present.

LGTM.

--
viresh