On Thu, 5 Dec 2024 at 19:01, Christian Marangi <ansuelsmth@xxxxxxxxx> wrote: > > On Thu, Dec 05, 2024 at 05:07:07PM +0100, Ulf Hansson wrote: > > On Wed, 4 Dec 2024 at 19:24, Christian Marangi <ansuelsmth@xxxxxxxxx> wrote: > > > > > > Document required property for Airoha EN7581 CPUFreq . > > > > > > On newer Airoha SoC, CPU Frequency is scaled indirectly with SMCCC commands > > > to ATF and no clocks are exposed to the OS. > > > > > > The SoC have performance state described by ID for each OPP, for this a > > > Power Domain is used that sets the performance state ID according to the > > > required OPPs defined in the CPU OPP tables. > > > > To clarify this, I would rather speak about a performance-domain with > > performance-levels, where each level corresponds to a frequency that > > is controlled by the FW/HW. > > (If Rob notice this and gets angry :P , v6 was posted 10 minutes before > the review from Rob, big coincidence. No intention of ignoring the > comments) > > I notice that power-domain schema also accepts node with > performance-domain. My concern is that the API we would use > (power-domain related) expect #power-domain-cells property and might > reject init with #power-performance-cells. You understood me wrong. I am not suggesting to use #power-performance-cells. The more established way to model performance domains is using "power-domain-cells" (a power-domain provider), which is capable of performance scaling. > > I have to check this but I think it's better to have a clear idea of > what the schema should be. > > > > > > > > > Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx> > > > Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> > > > --- > > > Changes v6: > > > - No changes > > > Changes v5: > > > - Add Reviewed-by tag > > > - Fix OPP node name error > > > - Rename cpufreq node name to power-domain > > > - Rename CPU node power domain name to perf > > > - Add model and compatible to example > > > Changes v4: > > > - Add this patch > > > > > > .../cpufreq/airoha,en7581-cpufreq.yaml | 262 ++++++++++++++++++ > > > 1 file changed, 262 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/cpufreq/airoha,en7581-cpufreq.yaml > > > > > > diff --git a/Documentation/devicetree/bindings/cpufreq/airoha,en7581-cpufreq.yaml b/Documentation/devicetree/bindings/cpufreq/airoha,en7581-cpufreq.yaml > > > new file mode 100644 > > > index 000000000000..7e36fa037e4b > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/cpufreq/airoha,en7581-cpufreq.yaml > > > @@ -0,0 +1,262 @@ > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > +%YAML 1.2 > > > +--- > > > +$id: http://devicetree.org/schemas/cpufreq/airoha,en7581-cpufreq.yaml# > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > + > > > +title: Airoha EN7581 CPUFreq > > > + > > > +maintainers: > > > + - Christian Marangi <ansuelsmth@xxxxxxxxx> > > > + > > > +description: | > > > + On newer Airoha SoC, CPU Frequency is scaled indirectly with SMCCC commands > > > + to ATF and no clocks are exposed to the OS. > > > + > > > + The SoC have performance state described by ID for each OPP, for this a > > > + Power Domain is used that sets the performance state ID according to the > > > + required OPPs defined in the CPU OPP tables. > > > + > > > +properties: > > > + compatible: > > > + const: airoha,en7581-cpufreq > > > + > > > + '#clock-cells': > > > + const: 0 > > > > I think Rob questioned this too. Why do we need a clock provider here? > > > > If this is only to keep the CPUfreq DT driver happy, I think this > > should be dropped. There is only a performance-domain here, right? > > > > As said in v5, the API is fun. > SMC have an OP to request the current frequency and that is provided in > MHz. > > Then it does have a command to se the global frequency and that is in > Index. > > Each index rapresent a particular frequency. > > For CPUFreq-DT a clock is mandatory, and is also good to provide one. Well, that's a separate discussion. Let's settle on the bindings first. > But in v5 Rob was O.K. for the clock. The main complain is for the OPP > table. We need the OPP table, else how would we be able to describe the available performance levels? > > > > + > > > + '#power-domain-cells': > > > + const: 0 > > > + > > > + operating-points-v2: true > > > + > > > +required: > > > + - compatible > > > + - '#clock-cells' > > > + - '#power-domain-cells' > > > + - operating-points-v2 > > > + > > > +additionalProperties: false > > > + > > > +examples: > > > + - | > > > + / { > > > + model = "Airoha EN7581 Evaluation Board"; > > > + compatible = "airoha,en7581-evb", "airoha,en7581"; > > > + > > > + #address-cells = <2>; > > > + #size-cells = <2>; > > > + > > > + cpus { > > > + #address-cells = <1>; > > > + #size-cells = <0>; > > > + > > > + cpu0: cpu@0 { > > > + device_type = "cpu"; > > > + compatible = "arm,cortex-a53"; > > > + reg = <0x0>; > > > + operating-points-v2 = <&cpu_opp_table>; > > > + enable-method = "psci"; > > > + clocks = <&cpu_pd>; > > > + clock-names = "cpu"; > > > + power-domains = <&cpu_pd>; > > > + power-domain-names = "perf"; > > > + next-level-cache = <&l2>; > > > + #cooling-cells = <2>; > > > + }; > > > + > > > + cpu1: cpu@1 { > > > + device_type = "cpu"; > > > + compatible = "arm,cortex-a53"; > > > + reg = <0x1>; > > > + operating-points-v2 = <&cpu_opp_table>; > > > + enable-method = "psci"; > > > + clocks = <&cpu_pd>; > > > + clock-names = "cpu"; > > > + power-domains = <&cpu_pd>; > > > + power-domain-names = "perf"; > > > + next-level-cache = <&l2>; > > > + #cooling-cells = <2>; > > > + }; > > > + > > > + cpu2: cpu@2 { > > > + device_type = "cpu"; > > > + compatible = "arm,cortex-a53"; > > > + reg = <0x2>; > > > + operating-points-v2 = <&cpu_opp_table>; > > > + enable-method = "psci"; > > > + clocks = <&cpu_pd>; > > > + clock-names = "cpu"; > > > + power-domains = <&cpu_pd>; > > > + power-domain-names = "perf"; > > > + next-level-cache = <&l2>; > > > + #cooling-cells = <2>; > > > + }; > > > + > > > + cpu3: cpu@3 { > > > + device_type = "cpu"; > > > + compatible = "arm,cortex-a53"; > > > + reg = <0x3>; > > > + operating-points-v2 = <&cpu_opp_table>; > > > + enable-method = "psci"; > > > + clocks = <&cpu_pd>; > > > + clock-names = "cpu"; > > > + power-domains = <&cpu_pd>; > > > + power-domain-names = "perf"; > > > + next-level-cache = <&l2>; > > > + #cooling-cells = <2>; > > > + }; > > > + }; > > > + > > > + cpu_opp_table: opp-table-cpu { > > > + compatible = "operating-points-v2"; > > > + opp-shared; > > > + > > > + opp-500000000 { > > > + opp-hz = /bits/ 64 <500000000>; > > > + required-opps = <&smcc_opp0>; > > > + }; > > > + > > > + opp-550000000 { > > > + opp-hz = /bits/ 64 <550000000>; > > > + required-opps = <&smcc_opp1>; > > > + }; > > > + > > > + opp-600000000 { > > > + opp-hz = /bits/ 64 <600000000>; > > > + required-opps = <&smcc_opp2>; > > > + }; > > > + > > > + opp-650000000 { > > > + opp-hz = /bits/ 64 <650000000>; > > > + required-opps = <&smcc_opp3>; > > > + }; > > > + > > > + opp-7000000000 { > > > + opp-hz = /bits/ 64 <700000000>; > > > + required-opps = <&smcc_opp4>; > > > + }; > > > + > > > + opp-7500000000 { > > > + opp-hz = /bits/ 64 <750000000>; > > > + required-opps = <&smcc_opp5>; > > > + }; > > > + > > > + opp-8000000000 { > > > + opp-hz = /bits/ 64 <800000000>; > > > + required-opps = <&smcc_opp6>; > > > + }; > > > + > > > + opp-8500000000 { > > > + opp-hz = /bits/ 64 <850000000>; > > > + required-opps = <&smcc_opp7>; > > > + }; > > > + > > > + opp-9000000000 { > > > + opp-hz = /bits/ 64 <900000000>; > > > + required-opps = <&smcc_opp8>; > > > + }; > > > + > > > + opp-9500000000 { > > > + opp-hz = /bits/ 64 <950000000>; > > > + required-opps = <&smcc_opp9>; > > > + }; > > > + > > > + opp-10000000000 { > > > + opp-hz = /bits/ 64 <1000000000>; > > > + required-opps = <&smcc_opp10>; > > > + }; > > > + > > > + opp-10500000000 { > > > + opp-hz = /bits/ 64 <1050000000>; > > > + required-opps = <&smcc_opp11>; > > > + }; > > > + > > > + opp-11000000000 { > > > + opp-hz = /bits/ 64 <1100000000>; > > > + required-opps = <&smcc_opp12>; > > > + }; > > > + > > > + opp-11500000000 { > > > + opp-hz = /bits/ 64 <1150000000>; > > > + required-opps = <&smcc_opp13>; > > > + }; > > > + > > > + opp-12000000000 { > > > + opp-hz = /bits/ 64 <1200000000>; > > > + required-opps = <&smcc_opp14>; > > > + }; > > > + }; > > > + > > > + cpu_smcc_opp_table: opp-table-smcc { > > > + compatible = "operating-points-v2"; > > > + > > > + smcc_opp0: opp-0 { > > > + opp-level = <0>; > > > + }; > > > + > > > + smcc_opp1: opp-1 { > > > + opp-level = <1>; > > > + }; > > > + > > > + smcc_opp2: opp-2 { > > > + opp-level = <2>; > > > + }; > > > + > > > + smcc_opp3: opp-3 { > > > + opp-level = <3>; > > > + }; > > > + > > > + smcc_opp4: opp-4 { > > > + opp-level = <4>; > > > + }; > > > + > > > + smcc_opp5: opp-5 { > > > + opp-level = <5>; > > > + }; > > > + > > > + smcc_opp6: opp-6 { > > > + opp-level = <6>; > > > + }; > > > + > > > + smcc_opp7: opp-7 { > > > + opp-level = <7>; > > > + }; > > > + > > > + smcc_opp8: opp-8 { > > > + opp-level = <8>; > > > + }; > > > + > > > + smcc_opp9: opp-9 { > > > + opp-level = <9>; > > > + }; > > > + > > > + smcc_opp10: opp-10 { > > > + opp-level = <10>; > > > + }; > > > + > > > + smcc_opp11: opp-11 { > > > + opp-level = <11>; > > > + }; > > > + > > > + smcc_opp12: opp-12 { > > > + opp-level = <12>; > > > + }; > > > + > > > + smcc_opp13: opp-13 { > > > + opp-level = <13>; > > > + }; > > > + > > > + smcc_opp14: opp-14 { > > > + opp-level = <14>; > > > + }; > > > + }; > > > + > > > + cpu_pd: power-domain { > > > > Nitpick: We could use the name *performance-domain* here instead, that > > would make it even more clear what this node describes. > > > > > + compatible = "airoha,en7581-cpufreq"; > > > + > > > + operating-points-v2 = <&cpu_smcc_opp_table>; > > > + > > > + #power-domain-cells = <0>; > > > + #clock-cells = <0>; > > > + }; > > > + }; > > > -- > > > 2.45.2 > > > > > > > With those changes I am still happy with this approach, so feel free > > to keep my Reviewed-by tag. > > > > Thanks a lot for the hint. What I think should be understood and we need > to agree on is the OPP table. > > Currently we have an implementation that is > > CPU-OPP-Table: > - OPP Freq in MHz 1 > - connection to OPP for performance-domain > ... > > Performance-Domain-OPP-Table: > - OPP Level 1 (connected to OPP Freq) > > Is the double table the problem and we should find a way to unify it in > something like > CPU-OPP-Table: > - OPP Freq in MHz 1 > OPP Level 1 > > - OPP Freq in MHz 2 > OPP Level 2 > > ... > > From what I notice this is problematic as the 2 subsystems require > dedicated table for each other. > In any case I think a table of freq is a MUST. Dropping that would > result in not giving to the user an idea of the supported frequency and > scaling stats. Why do we need to invent something new here to describe this HW? Doesn't the existing OPP v2 DT bindings with the required-opps property, along with the power-domains bindings work as is? Kind regards Uffe
