Qualcomm Technologies, Inc. GPU powerlevels

Powerlevels are defined in sets by qcom,gpu-pwrlevels. Multiple sets (bins)
can be defined within qcom,gpu-pwrelvel-bins. Each powerlevel defines a
voltage, bus, bandwidth level, and a DVM value.

- qcom,gpu-pwrlevel-bins:	Contains one or more qcom,gpu-pwrlevels sets

Properties:
- compatible:			Must be qcom,gpu-pwrlevel-bins
- qcom,gpu-pwrlevels:		Defines a set of powerlevels

Properties:
- qcom,speed-bin:		Speed bin identifier for the set - must match
				the value read from the hardware
- qcom,initial-pwrlevel:	GPU wakeup powerlevel

- qcom,gpu-pwrlevel:		A single powerlevel

- qcom,ca-target-pwrlevel:
				This value indicates which qcom,gpu-pwrlevel
				to jump on in case of context aware power level
				jump.
Required Properties:
- reg:				Index of the powerlevel (0 = highest perf)
- qcom,gpu-freq			GPU frequency for the powerlevel (in Hz)
- qcom,bus-freq			Index to a bus level (defined by the bus
				settings).

- qcom,bus-freq-ddrX		If specified, define the DDR specific bus
				frequency for the power level.  X will be the
				return value from of_fdt_get_ddrtype().

Optional Properties:
- qcom,bus-min			Minimum bus level to set for the power level

- qcom,bus-min-ddrX		If specified, define the DDR specific minimum
				bus level for the power level.  X will be the
				return value from of_fdt_get_ddrtype().

- qcom,bus-max			maximum bus level to set for the power level

- qcom,bus-max-ddrX		If specified, define the DDR specific maximum
				bus level for the power level.  X will be the
				return value from of_fdt_get_ddrtype().

- qcom,acd-level:		Value that is used as a register setting for
				the ACD power feature. It helps to determine
				the threshold for when ACD activates. Zero is
				the default value, and the setting where ACD
				will never activate.
Example:

qcom,gpu-pwrlevel@6 {
	reg = <6>;
	qcom,gpu-freq = <0>;
	qcom,bus-freq = <0>;
	qcom,bus-min = <0>;
	qcom,bus-max = <0>;
	qcom,acd-level = <0xffffffff>;
};

Example for DDR4/DDR5 specific part:

qcom,gpu-pwrlevel@6 {
	reg = <6>;
	qcom,gpu-freq = <480000000>;

	/* DDR5 */
	qcom,bus-freq-ddr8 = <10>;
	qcom,bus-min-ddr8 = <9>;
	qcom,bus-max-ddr8 = <11>;

	/* DDR 4 */
	qcom,bus-freq-ddr7 = <9>;
	qcom,bus-min-ddr7 = <7>;
	qcom,bus-max-ddr7 = <9>;

	qcom,acd-level = <0xffffffff>;
};