Messages in this thread | | | Date | Mon, 22 Jun 2020 12:52:47 +0530 | From | Viresh Kumar <> | Subject | Re: [TEGRA194_CPUFREQ Patch v3 1/4] dt-bindings: arm: Add t194 ccplex compatible and bpmp property |
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On 22-06-20, 03:04, Sumit Gupta wrote: > To do frequency scaling on all CPUs within T194 CPU Complex, we need > to query BPMP for data on valid operating points. Document a compatible > string under 'cpus' node to represent the CPU Complex for binding drivers > like cpufreq which don't have their node or CPU Complex node to bind to. > Also, document a property to point to the BPMP device that can be queried > for all CPUs.
You shouldn't be putting how linux is going to use this information and entries shouldn't be made just so cpufreq can bind to a driver.
Though I see that this is a real hardware register which you can use to interact with the firmware ? And so it makes sense to have it, maybe in different form though.
I will let Rob explain what would be the right way of doing this though.
> > Signed-off-by: Sumit Gupta <sumitg@nvidia.com> > --- > Documentation/devicetree/bindings/arm/cpus.yaml | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/Documentation/devicetree/bindings/arm/cpus.yaml b/Documentation/devicetree/bindings/arm/cpus.yaml > index a018147..737b55e 100644 > --- a/Documentation/devicetree/bindings/arm/cpus.yaml > +++ b/Documentation/devicetree/bindings/arm/cpus.yaml > @@ -162,6 +162,7 @@ properties: > - nvidia,tegra132-denver > - nvidia,tegra186-denver > - nvidia,tegra194-carmel > + - nvidia,tegra194-ccplex > - qcom,krait > - qcom,kryo > - qcom,kryo260 > @@ -255,6 +256,14 @@ properties: > > where voltage is in V, frequency is in MHz. > > + nvidia,bpmp: > + $ref: '/schemas/types.yaml#/definitions/phandle' > + descrption: | > + Specifies the bpmp node that needs to be queried to get > + operating point data for all CPUs. > + > + Optional for NVIDIA Tegra194 Carmel CPUs > + > power-domains: > $ref: '/schemas/types.yaml#/definitions/phandle-array' > description: > -- > 2.7.4
-- viresh
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