On 04-04-19, 07:09, Niklas Cassel wrote: > Add 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. > > Co-developed-by: Jorge Ramirez-Ortiz <[email protected]> > Signed-off-by: Jorge Ramirez-Ortiz <[email protected]> > Signed-off-by: Niklas Cassel <[email protected]> > --- > .../devicetree/bindings/opp/qcom-opp.txt | 24 +++++++++++++++++++ > 1 file changed, 24 insertions(+) > create mode 100644 Documentation/devicetree/bindings/opp/qcom-opp.txt > > diff --git a/Documentation/devicetree/bindings/opp/qcom-opp.txt > b/Documentation/devicetree/bindings/opp/qcom-opp.txt > new file mode 100644 > index 000000000000..d24280467db7 > --- /dev/null > +++ b/Documentation/devicetree/bindings/opp/qcom-opp.txt > @@ -0,0 +1,24 @@ > +Qualcomm OPP bindings to describe OPP nodes > + > +The bindings are based on top of the operating-points-v2 bindings > +described in Documentation/devicetree/bindings/opp/opp.txt > +Additional properties are described below. > + > +* OPP Table Node > + > +Required properties: > +- compatible: Allow OPPs to express their compatibility. It should be: > + "operating-points-v2-qcom-level" > + > +* OPP Node > + > +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,opp-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.
I know we discussed this sometime back and so you implemented it this way. Looking at the implementation of the CPR driver, I now wonder if that was a good choice. Technically a single domain can manage many devices, a big and a little CPU for example and then we will have different highest frequencies for both of them. How will we configure the CPR hardware in such a case ? Isn't the programming per-device ? -- viresh
