Re: [PATCH v6 15/15] dt-bindings: cpufreq: Document operating-points-v2-krait-cpu

From: Sricharan R
Date: Fri Feb 09 2018 - 00:32:07 EST

Hi Rob,

On 2/9/2018 8:24 AM, Rob Herring wrote:
> On Tue, Feb 06, 2018 at 09:38:28AM +0530, Sricharan R wrote:
>> In Certain QCOM SoCs like ipq8064, apq8064, msm8960, msm8974
>> that has KRAIT processors the voltage/current value of each OPP
>> varies based on the silicon variant in use.
>> operating-points-v2-krait-cpu specifies the phandle to nvmem efuse cells
>> and the operating-points-v2 table for each opp. The qcom-cpufreq driver
>> reads the efuse value from the SoC to provide the required information
>> that is used to determine the voltage and current value for each OPP of
>> operating-points-v2 table when it is parsed by the OPP framework.
>>
>> Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>
>> ---
>> .../devicetree/bindings/cpufreq/krait-cpufreq.txt | 363 +++++++++++++++++++++
>> 1 file changed, 363 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/cpufreq/krait-cpufreq.txt
>>
>> diff --git a/Documentation/devicetree/bindings/cpufreq/krait-cpufreq.txt b/Documentation/devicetree/bindings/cpufreq/krait-cpufreq.txt
>> new file mode 100644
>> index 0000000..e7351f7
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/cpufreq/krait-cpufreq.txt
>> @@ -0,0 +1,363 @@
>> +QCOM KRAIT CPUFreq and OPP bindings
>> +===================================
>> +
>> +In Certain QCOM SoCs like ipq8064, apq8064, msm8960, msm8974
>> +that has KRAIT processors the voltage value of each OPP varies
>> +based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables
>> +defines the voltage and current value based on the speed/pvs/version
>> +combination blown in the efuse. The qcom-cpufreq driver reads the efuse
>> +value from the SoC to provide the OPP framework with required information.
>> +This is used to determine the voltage and current value for each OPP of
>> +operating-points-v2 table when it is parsed by the OPP framework.
>> +
>> +Required properties:
>> +--------------------
>> +In 'cpus' nodes:
>> +- operating-points-v2: Phandle to the operating-points-v2 table to use.
>> +
>> +In 'operating-points-v2' table:
>> +- compatible: Should be
>> + - 'operating-points-v2-krait-cpu' for ipq8064, apq8064, msm8960,
>> + msm8974.
>> +- nvmem-cells: A phandle pointing to a nvmem-cells node representing the
>> + efuse registers that has information about the
>> + speedbin/pvs/version that is used to select the right
>> + voltage/current value pair. Note that the length field of the
>> + nvmem-cell is used to differentiate between format 'A' or 'B'
>> + efuse settings. len of '4' bytes is for format 'A' and '8'
>> + bytes for format 'B'. Please refer the for nvmem-cells
>> + bindings Documentation/devicetree/bindings/nvmem/nvmem.txt
>> + and also examples below for both the cases.
>> +Example 1:
>> +---------
>> +
>> +/* For arch/arm/boot/dts/apq8064.dtsi --> format 'A' */
>> +cpus {
>> + #address-cells = <1>;
>> + #size-cells = <0>;
>> +
>> + CPU0: cpu@0 {
>> + compatible = "qcom,krait";
>> + enable-method = "qcom,kpss-acc-v1";
>> + device_type = "cpu";
>> + reg = <0>;
>> + next-level-cache = <&L2>;
>> + qcom,acc = <&acc0>;
>> + qcom,saw = <&saw0>;
>> + cpu-idle-states = <&CPU_SPC>;
>> + operating-points-v2 = <&cpu_opp_table>;
>> + };
>> +};
>> +
>> +qfprom: qfprom@700000 {
>> + compatible = "qcom,qfprom";
>> + reg = <0x00700000 0x1000>;
>> + #address-cells = <1>;
>> + #size-cells = <1>;
>> + ranges;
>> + pvs_efuse: pvs {
>> + reg = <0xc0 0x4>;
>> + };
>> +};
>> +
>> +cpu_opp_table: opp-table {
>> + compatible = "operating-points-v2-krait-cpu";
>> + nvmem-cells = <&pvs_efuse>;
>> +
>> + /*
>> + * Missing opp-shared property means CPUs switch DVFS states
>> + * independently.
>> + */
>> +
>> + opp-918000000 {
>> + opp-hz = /bits/ 64 <918000000>;
>> + opp-microvolt-speed0-pvs0-v0 = <1100000>;
>
> Where is this property defined? I'm not that happy with it, but don't
> have a better suggestion. Maybe make pvsN be an array of values with 0
> for any skipped indexes? The '-v0' seems pointless.
>

'opp-microvolt' is the property that comes from OPP-V2 bindings and rest
of the string "speed%s-pvs%s-v%s" gets concatenated to the string
by the cpufreq driver using dev_pm_opp_set_prop_name api. So all
the three speed,pvs,v (version) come from efuse and can vary.
Just that in the data so far, v is always '0'.

>> + opp-microvolt-speed0-pvs1-v0 = <1050000>;
>> + opp-microvolt-speed0-pvs3-v0 = <1000000>;
>> + opp-microvolt-speed0-pvs4-v0 = <975000>;
>> + opp-microvolt-speed1-pvs0-v0 = <1025000>;
>> + opp-microvolt-speed1-pvs1-v0 = <1000000>;
>> + opp-microvolt-speed1-pvs2-v0 = <950000>;
>> + opp-microvolt-speed1-pvs3-v0 = <925000>;
>> + opp-microvolt-speed1-pvs4-v0 = <900000>;
>> + opp-microvolt-speed1-pvs5-v0 = <900000>;
>> + opp-microvolt-speed1-pvs6-v0 = <900000>;
>> + opp-microvolt-speed2-pvs0-v0 = <975000>;
>> + opp-microvolt-speed2-pvs1-v0 = <950000>;
>> + opp-microvolt-speed2-pvs2-v0 = <925000>;
>> + opp-microvolt-speed2-pvs3-v0 = <912500>;
>> + opp-microvolt-speed2-pvs4-v0 = <900000>;
>> + opp-microvolt-speed2-pvs5-v0 = <900000>;
>> + opp-microvolt-speed2-pvs6-v0 = <900000>;
>> + opp-microvolt-speed14-pvs0-v0 = <1025000>;
>> + opp-microvolt-speed14-pvs1-v0 = <1000000>;
>> + opp-microvolt-speed14-pvs2-v0 = <950000>;
>> + opp-microvolt-speed14-pvs3-v0 = <925000>;
>> + opp-microvolt-speed14-pvs4-v0 = <900000>;
>> + opp-microvolt-speed14-pvs5-v0 = <900000>;
>> + opp-microvolt-speed14-pvs6-v0 = <900000>;
>> + };
>> +
>> + opp-810000000 {
>> + opp-hz = /bits/ 64 <810000000>;
>> + opp-microvolt-speed0-pvs0-v0 = < 1075000>;
>> + opp-microvolt-speed0-pvs1-v0 = < 1025000>;
>> + opp-microvolt-speed0-pvs3-v0 = < 975000>;
>> + opp-microvolt-speed0-pvs3-v0 = < 962500>;
>> + opp-microvolt-speed1-pvs0-v0 = < 1000000>;
>> + opp-microvolt-speed1-pvs1-v0 = < 975000>;
>> + opp-microvolt-speed1-pvs2-v0 = < 937500>;
>> + opp-microvolt-speed1-pvs3-v0 = < 900000>;
>> + opp-microvolt-speed1-pvs4-v0 = < 887500>;
>> + opp-microvolt-speed1-pvs5-v0 = < 887500>;
>> + opp-microvolt-speed1-pvs6-v0 = < 887500>;
>> + opp-microvolt-speed2-pvs0-v0 = < 962500>;
>> + opp-microvolt-speed2-pvs1-v0 = < 937500>;
>> + opp-microvolt-speed2-pvs2-v0 = < 912500>;
>> + opp-microvolt-speed2-pvs3-v0 = < 900000>;
>> + opp-microvolt-speed2-pvs4-v0 = < 887500>;
>> + opp-microvolt-speed2-pvs5-v0 = < 887500>;
>> + opp-microvolt-speed2-pvs6-v0 = < 887500>;
>
> Some space then tab issues on the above. Also, drop the space after the
> '<'.

ok, will fix it.

>
>> + opp-microvolt-speed14-pvs0-v0 = < 1000000>;
>> + opp-microvolt-speed14-pvs1-v0 = < 975000>;
>> + opp-microvolt-speed14-pvs2-v0 = < 937500>;
>> + opp-microvolt-speed14-pvs3-v0 = < 900000>;
>> + opp-microvolt-speed14-pvs4-v0 = < 887500>;
>> + opp-microvolt-speed14-pvs5-v0 = < 887500>;
>> + opp-microvolt-speed14-pvs6-v0 = < 887500>;
>> + };
>> +
>> + opp-702000000 {
>> + opp-hz = /bits/ 64 <702000000>;
>> + opp-microvolt-speed0-pvs0-v0 = <1025000>;
>> + opp-microvolt-speed0-pvs1-v0 = <975000>;
>> + opp-microvolt-speed0-pvs3-v0 = <925000>;
>> + opp-microvolt-speed0-pvs3-v0 = <925000>;
>> + opp-microvolt-speed1-pvs0-v0 = <962500>;
>> + opp-microvolt-speed1-pvs1-v0 = <962500>;
>> + opp-microvolt-speed1-pvs2-v0 = <925000>;
>> + opp-microvolt-speed1-pvs3-v0 = <900000>;
>> + opp-microvolt-speed1-pvs4-v0 = <875000>;
>> + opp-microvolt-speed1-pvs5-v0 = <875000>;
>> + opp-microvolt-speed1-pvs6-v0 = <875000>;
>> + opp-microvolt-speed2-pvs0-v0 = <950000>;
>> + opp-microvolt-speed2-pvs1-v0 = <925000>;
>> + opp-microvolt-speed2-pvs2-v0 = <900000>;
>> + opp-microvolt-speed2-pvs3-v0 = <900000>;
>> + opp-microvolt-speed2-pvs4-v0 = <875000>;
>> + opp-microvolt-speed2-pvs5-v0 = <875000>;
>> + opp-microvolt-speed2-pvs6-v0 = <875000>;
>> + opp-microvolt-speed14-pvs0-v0 = <962500>;
>> + opp-microvolt-speed14-pvs1-v0 = <962500>;
>> + opp-microvolt-speed14-pvs2-v0 = <925000>;
>> + opp-microvolt-speed14-pvs3-v0 = <900000>;
>> + opp-microvolt-speed14-pvs4-v0 = <875000>;
>> + opp-microvolt-speed14-pvs5-v0 = <875000>;
>> + opp-microvolt-speed14-pvs6-v0 = <875000>;
>> + };
>> +
>> + opp-594000000 {
>> + opp-hz = /bits/ 64 <594000000>;
>> + opp-microvolt-speed0-pvs0-v0 = <1000000>;
>> + opp-microvolt-speed0-pvs1-v0 = <950000>;
>> + opp-microvolt-speed0-pvs3-v0 = <900000>;
>> + opp-microvolt-speed0-pvs3-v0 = <900000>;
>> + opp-microvolt-speed1-pvs0-v0 = <950000>;
>> + opp-microvolt-speed1-pvs1-v0 = <950000>;
>> + opp-microvolt-speed1-pvs2-v0 = <925000>;
>> + opp-microvolt-speed1-pvs3-v0 = <900000>;
>> + opp-microvolt-speed1-pvs4-v0 = <875000>;
>> + opp-microvolt-speed1-pvs5-v0 = <875000>;
>> + opp-microvolt-speed1-pvs6-v0 = <875000>;
>> + opp-microvolt-speed2-pvs0-v0 = <950000>;
>> + opp-microvolt-speed2-pvs1-v0 = <925000>;
>> + opp-microvolt-speed2-pvs2-v0 = <900000>;
>> + opp-microvolt-speed2-pvs3-v0 = <900000>;
>> + opp-microvolt-speed2-pvs4-v0 = <875000>;
>> + opp-microvolt-speed2-pvs5-v0 = <875000>;
>> + opp-microvolt-speed2-pvs6-v0 = <875000>;
>
> More space then tab issues after the '='.
>
ok, will fix.

Regards,
Sricharan

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