0001 Texas Instruments OMAP compatible OPP supply description
0002
0003 OMAP5, DRA7, and AM57 family of SoCs have Class0 AVS eFuse registers which
0004 contain data that can be used to adjust voltages programmed for some of their
0005 supplies for more efficient operation. This binding provides the information
0006 needed to read these values and use them to program the main regulator during
0007 an OPP transitions.
0008
0009 Also, some supplies may have an associated vbb-supply which is an Adaptive Body
0010 Bias regulator which much be transitioned in a specific sequence with regards
0011 to the vdd-supply and clk when making an OPP transition. By supplying two
0012 regulators to the device that will undergo OPP transitions we can make use
0013 of the multi regulator binding that is part of the OPP core described here [1]
0014 to describe both regulators needed by the platform.
0015
0016 [1] Documentation/devicetree/bindings/opp/opp-v2.yaml
0017
0018 Required Properties for Device Node:
0019 - vdd-supply: phandle to regulator controlling VDD supply
0020 - vbb-supply: phandle to regulator controlling Body Bias supply
0021 (Usually Adaptive Body Bias regulator)
0022
0023 Required Properties for opp-supply node:
0024 - compatible: Should be one of:
0025 "ti,omap-opp-supply" - basic OPP supply controlling VDD and VBB
0026 "ti,omap5-opp-supply" - OMAP5+ optimized voltages in efuse(class0)VDD
0027 along with VBB
0028 "ti,omap5-core-opp-supply" - OMAP5+ optimized voltages in efuse(class0) VDD
0029 but no VBB.
0030 - reg: Address and length of the efuse register set for the device (mandatory
0031 only for "ti,omap5-opp-supply")
0032 - ti,efuse-settings: An array of u32 tuple items providing information about
0033 optimized efuse configuration. Each item consists of the following:
0034 volt: voltage in uV - reference voltage (OPP voltage)
0035 efuse_offseet: efuse offset from reg where the optimized voltage is stored.
0036 - ti,absolute-max-voltage-uv: absolute maximum voltage for the OPP supply.
0037
0038 Example:
0039
0040 /* Device Node (CPU) */
0041 cpus {
0042 cpu0: cpu@0 {
0043 device_type = "cpu";
0044
0045 ...
0046
0047 vdd-supply = <&vcc>;
0048 vbb-supply = <&abb_mpu>;
0049 };
0050 };
0051
0052 /* OMAP OPP Supply with Class0 registers */
0053 opp_supply_mpu: opp_supply@4a003b20 {
0054 compatible = "ti,omap5-opp-supply";
0055 reg = <0x4a003b20 0x8>;
0056 ti,efuse-settings = <
0057 /* uV offset */
0058 1060000 0x0
0059 1160000 0x4
0060 1210000 0x8
0061 >;
0062 ti,absolute-max-voltage-uv = <1500000>;
0063 };
