Re: [PATCH v8 1/2] dt-bindings: cpufreq: Introduce QCOM CPUFREQ Firmware bindings

[Taniya Das <tdas@codeaurora.org>]

Hello Rob,

Thanks for your review comments.

On 9/27/2018 9:01 PM, Rob Herring wrote:
> On Sun, Sep 23, 2018 at 04:03:12PM +0530, Taniya Das wrote:
>> Add QCOM cpufreq firmware device bindings for Qualcomm Technology Inc's
>> SoCs. This is required for managing the cpu frequency transitions which are
>> controlled by the hardware engine.
>>
>> Signed-off-by: Taniya Das <tdas@codeaurora.org>
>> ---
>>   .../bindings/cpufreq/cpufreq-qcom-hw.txt           | 169 +++++++++++++++++++++
>>   1 file changed, 169 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.txt
>>
>> diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.txt
>> new file mode 100644
>> index 0000000..c06941c
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.txt
>> @@ -0,0 +1,169 @@
>> +Qualcomm Technologies, Inc. CPUFREQ Bindings
>> +
>> +CPUFREQ HW is a hardware engine used by some Qualcomm Technologies, Inc. (QTI)
>> +SoCs to manage frequency in hardware. It is capable of controlling frequency
>> +for multiple clusters.
>> +
>> +Properties:
>> +- compatible
>> +	Usage:		required
>> +	Value type:	<string>
>> +	Definition:	must be "qcom,cpufreq-hw".
>> +
>> +- clocks
>> +	Usage:		required
>> +	Value type:	<phandle> From common clock binding.
>> +	Definition:	clock handle for XO clock and GPLL0 clock.
>> +
>> +- clock-names
>> +	Usage:		required
>> +	Value type:	<string> From common clock binding.
>> +	Definition:	must be "xo", "cpu_clk".
>> +
>> +- reg
>> +	Usage:		required
>> +	Value type:	<prop-encoded-array>
>> +	Definition:	Addresses and sizes for the memory of the HW bases in
>> +			each frequency domain.
>> +- reg-names
>> +	Usage:		Optional
>> +	Value type:	<string>
>> +	Definition:	Frequency domain name i.e.
>> +			"freq-domain0", "freq-domain1".
>> +
>> +* Property qcom,freq-domain
>> +Devices supporting freq-domain must set their "qcom,freq-domain" property with
>> +phandle to a cpufreq_hw followed by the Domain ID(0/1) in the CPU DT node.
>> +
>> +
>> +Example:
>> +
>> +Example 1: Dual-cluster, Quad-core per cluster. CPUs within a cluster switch
>> +DCVS state together.
>> +
>> +/ {
>> +	cpus {
>> +		#address-cells = <2>;
>> +		#size-cells = <0>;
>> +
>> +		CPU0: cpu@0 {
>> +			device_type = "cpu";
>> +			compatible = "qcom,kryo385";
>> +			reg = <0x0 0x0>;
>> +			enable-method = "psci";
>> +			next-level-cache = <&L2_0>;
>> +			qcom,freq-domain = <&cpufreq_hw 0>;
>> +			L2_0: l2-cache {
>> +				compatible = "cache";
>> +				next-level-cache = <&L3_0>;
>> +				L3_0: l3-cache {
>> +				      compatible = "cache";
>> +				};
>> +			};
>> +		};
>> +
>> +		CPU1: cpu@100 {
>> +			device_type = "cpu";
>> +			compatible = "qcom,kryo385";
>> +			reg = <0x0 0x100>;
>> +			enable-method = "psci";
>> +			next-level-cache = <&L2_100>;
>> +			qcom,freq-domain = <&cpufreq_hw 0>;
>> +			L2_100: l2-cache {
>> +				compatible = "cache";
>> +				next-level-cache = <&L3_0>;
>> +			};
>> +		};
>> +
>> +		CPU2: cpu@200 {
>> +			device_type = "cpu";
>> +			compatible = "qcom,kryo385";
>> +			reg = <0x0 0x200>;
>> +			enable-method = "psci";
>> +			next-level-cache = <&L2_200>;
>> +			qcom,freq-domain = <&cpufreq_hw 0>;
>> +			L2_200: l2-cache {
>> +				compatible = "cache";
>> +				next-level-cache = <&L3_0>;
>> +			};
>> +		};
>> +
>> +		CPU3: cpu@300 {
>> +			device_type = "cpu";
>> +			compatible = "qcom,kryo385";
>> +			reg = <0x0 0x300>;
>> +			enable-method = "psci";
>> +			next-level-cache = <&L2_300>;
>> +			qcom,freq-domain = <&cpufreq_hw 0>;
>> +			L2_300: l2-cache {
>> +				compatible = "cache";
>> +				next-level-cache = <&L3_0>;
>> +			};
>> +		};
>> +
>> +		CPU4: cpu@400 {
>> +			device_type = "cpu";
>> +			compatible = "qcom,kryo385";
>> +			reg = <0x0 0x400>;
>> +			enable-method = "psci";
>> +			next-level-cache = <&L2_400>;
>> +			qcom,freq-domain = <&cpufreq_hw 1>;
>> +			L2_400: l2-cache {
>> +				compatible = "cache";
>> +				next-level-cache = <&L3_0>;
>> +			};
>> +		};
>> +
>> +		CPU5: cpu@500 {
>> +			device_type = "cpu";
>> +			compatible = "qcom,kryo385";
>> +			reg = <0x0 0x500>;
>> +			enable-method = "psci";
>> +			next-level-cache = <&L2_500>;
>> +			qcom,freq-domain = <&cpufreq_hw 1>;
>> +			L2_500: l2-cache {
>> +				compatible = "cache";
>> +				next-level-cache = <&L3_0>;
>> +			};
>> +		};
>> +
>> +		CPU6: cpu@600 {
>> +			device_type = "cpu";
>> +			compatible = "qcom,kryo385";
>> +			reg = <0x0 0x600>;
>> +			enable-method = "psci";
>> +			next-level-cache = <&L2_600>;
>> +			qcom,freq-domain = <&cpufreq_hw 1>;
>> +			L2_600: l2-cache {
>> +				compatible = "cache";
>> +				next-level-cache = <&L3_0>;
>> +			};
>> +		};
>> +
>> +		CPU7: cpu@700 {
>> +			device_type = "cpu";
>> +			compatible = "qcom,kryo385";
>> +			reg = <0x0 0x700>;
>> +			enable-method = "psci";
>> +			next-level-cache = <&L2_700>;
>> +			qcom,freq-domain = <&cpufreq_hw 1>;
>> +			L2_700: l2-cache {
>> +				compatible = "cache";
>> +				next-level-cache = <&L3_0>;
>> +			};
>> +		};
>> +	};
>> +
>> + soc {
>> +	cpufreq_hw: qcom,cpufreq-hw {
> 
> Should have a unit-address and node names should be generic. We don't
> really have one for this, but let's go with 'cpufreq', so:
> 
> cpufreq@17d43000
> 

Thanks Rob, will update in the next patch.

>> +		compatible = "qcom,cpufreq-hw";
>> +		reg = <0x17d43000 0x1400>, <0x17d45800 0x1400>;
>> +		reg-names = "freq-domain0", "freq-domain1";
>> +
>> +		clocks = <&rpmhcc RPMH_CXO_CLK>, <&gcc GPLL0>;
>> +		clock-names = "xo", "cpu_clk";
>> +
>> +		#freq-domains-cells = <1>
> 
> Not documented, but I don't think you need this if it is always 1 and
> because this is not a common binding.
> 

I would add it in the next patch just to keep it documented.

> Rob
> 

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