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Diffstat (limited to 'Documentation/devicetree/bindings/opp/ti-omap5-opp-supply.txt')
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diff --git a/Documentation/devicetree/bindings/opp/ti-omap5-opp-supply.txt b/Documentation/devicetree/bindings/opp/ti-omap5-opp-supply.txt new file mode 100644 index 000000000000..832346e489a3 --- /dev/null +++ b/Documentation/devicetree/bindings/opp/ti-omap5-opp-supply.txt @@ -0,0 +1,63 @@ +Texas Instruments OMAP compatible OPP supply description + +OMAP5, DRA7, and AM57 family of SoCs have Class0 AVS eFuse registers which +contain data that can be used to adjust voltages programmed for some of their +supplies for more efficient operation. This binding provides the information +needed to read these values and use them to program the main regulator during +an OPP transitions. + +Also, some supplies may have an associated vbb-supply which is an Adaptive Body +Bias regulator which much be transitioned in a specific sequence with regards +to the vdd-supply and clk when making an OPP transition. By supplying two +regulators to the device that will undergo OPP transitions we can make use +of the multi regulator binding that is part of the OPP core described here [1] +to describe both regulators needed by the platform. + +[1] Documentation/devicetree/bindings/opp/opp.txt + +Required Properties for Device Node: +- vdd-supply: phandle to regulator controlling VDD supply +- vbb-supply: phandle to regulator controlling Body Bias supply + (Usually Adaptive Body Bias regulator) + +Required Properties for opp-supply node: +- compatible: Should be one of: + "ti,omap-opp-supply" - basic OPP supply controlling VDD and VBB + "ti,omap5-opp-supply" - OMAP5+ optimized voltages in efuse(class0)VDD + along with VBB + "ti,omap5-core-opp-supply" - OMAP5+ optimized voltages in efuse(class0) VDD + but no VBB. +- reg: Address and length of the efuse register set for the device (mandatory + only for "ti,omap5-opp-supply") +- ti,efuse-settings: An array of u32 tuple items providing information about + optimized efuse configuration. Each item consists of the following: + volt: voltage in uV - reference voltage (OPP voltage) + efuse_offseet: efuse offset from reg where the optimized voltage is stored. +- ti,absolute-max-voltage-uv: absolute maximum voltage for the OPP supply. + +Example: + +/* Device Node (CPU) */ +cpus { + cpu0: cpu@0 { + device_type = "cpu"; + + ... + + vdd-supply = <&vcc>; + vbb-supply = <&abb_mpu>; + }; +}; + +/* OMAP OPP Supply with Class0 registers */ +opp_supply_mpu: opp_supply@4a003b20 { + compatible = "ti,omap5-opp-supply"; + reg = <0x4a003b20 0x8>; + ti,efuse-settings = < + /* uV offset */ + 1060000 0x0 + 1160000 0x4 + 1210000 0x8 + >; + ti,absolute-max-voltage-uv = <1500000>; +}; |