MSM SPDM bandwidth monitor device

devfreq-spdm is a device that represents a device that is monitored by the SPDM
hardware to measure the traffic status of configured master ports on the bus.


Required properties:
-compatible:			Must be "qcom,devfreq_spdm"
-clock-names:			Clocks used to measure current bus frequency.
				Expected names are "cci_clk"
-clocks:			References to named clocks
-qcom,spdm-client:		Client id of the port being monitored
-qcom,bw-upstep:		Initial up vote size in MB/s
-qcom,bw-dwnstep:		Initial down vote size in MB/s
-qcom,max-vote:			Vote ceiling in MB/s
-qcom,ports:			SPDM ports used by this device
-qcom,alpha-up:			SPDM filter up alpha value
-qcom,alpha-down:		SPDM filter down alpha value
-qcom,bucket-size:		SPDM filter bucket size
-qcom,pl-freqs:			The driver supports different filter values at
				three different performance levels.  This value
				defines the cut-over frequenices
-qcom,reject-rate:		Desired rejection rate used to calculate
				SPDM threshold
-qcom,response-time-us:	Desired response time used to calculate
				SPDM threshold
-qcom,cci-response-time-us:	Desired response time used to calculate
				SPDM threshold when CCI is under heavy load
-qcom,max-cci-freq:		CCI frequency at which cci_response_time_us
				is used
-qcom,up-step-multp:		used to increase rate of growth on up votes
-qcom,spdm-interval:		down-vote polling interval

Example:
devfreq_spdm_cpu {
	compatible = "qcom,devfreq_spdm";
	qcom,msm-bus,name = "devfreq_spdm";
	qcom,msm-bus,num-cases = <2>;
	qcom,msm-bus,num-paths = <1>;
	qcom,msm-bus,vectors-KBps =
			<1 512 0 0>,
			<1 512 0 0>;
	qcom,spdm-client = <0>;

	clock-names = "cci_clk";
	clocks = <&clock_cpu clk_cci_clk>;

	qcom,bw-upstep = <100>;
	qcom,bw-dwnstep = <100>;
	qcom,max-vote = <10000>;
	qcom,up-step-multp = <2>;
	qcom,spdm-interval = <100>;

	qcom,ports = <16>;
	qcom,alpha-up = <7>;
	qcom,alpha-down = <15>;
	qcom,bucket-size = <8>;

	/*max pl1 freq, max pl2 freq*/
	qcom,pl-freqs = <149999999 150000000>;

	/* pl1 low, pl1 high, pl2 low, pl2 high, pl3 low, pl3 high */
	qcom,reject-rate = <5000 5000 5000 5000 5000 5000>;
	/* pl1 low, pl1 high, pl2 low, pl2 high, pl3 low, pl3 high */
	qcom,response-time-us = <220 220 2000 2000 900 900>;
	/* pl1 low, pl1 high, pl2 low, pl2 high, pl3 low, pl3 high */
	qcom,cci-response-time-us = <50 50 30 30 20 20>;
	qcom,max-cci-freq = <600000000>;
};

This device is always used with the SPDM governor which requires a device tree
entry to know what IRQ to respond to.

Required properties:
-compatible			Must be "qcom,gov_spdm_hyp"
-interrupt-names		SPDM irq to handle.  Name should be "spdm-irq"
-interrupts			The interrupt number the SPDM hw is assigned

Example:
devfreq_spdm_gov {
	compatible = "qcom,gov_spdm_hyp";
	interrupt-names = "spdm-irq";
	interrupts = <0 192 0>;
};