qcom,saw2.txt 1.9 KB

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  1. SPM AVS Wrapper 2 (SAW2)
  2. The SAW2 is a wrapper around the Subsystem Power Manager (SPM) and the
  3. Adaptive Voltage Scaling (AVS) hardware. The SPM is a programmable
  4. power-controller that transitions a piece of hardware (like a processor or
  5. subsystem) into and out of low power modes via a direct connection to
  6. the PMIC. It can also be wired up to interact with other processors in the
  7. system, notifying them when a low power state is entered or exited.
  8. Multiple revisions of the SAW hardware are supported using these Device Nodes.
  9. SAW2 revisions differ in the register offset and configuration data. Also, the
  10. same revision of the SAW in different SoCs may have different configuration
  11. data due the the differences in hardware capabilities. Hence the SoC name, the
  12. version of the SAW hardware in that SoC and the distinction between cpu (big
  13. or Little) or cache, may be needed to uniquely identify the SAW register
  14. configuration and initialization data. The compatible string is used to
  15. indicate this parameter.
  16. PROPERTIES
  17. - compatible:
  18. Usage: required
  19. Value type: <string>
  20. Definition: Must have
  21. "qcom,saw2"
  22. A more specific value could be one of:
  23. "qcom,apq8064-saw2-v1.1-cpu"
  24. "qcom,msm8974-saw2-v2.1-cpu"
  25. "qcom,apq8084-saw2-v2.1-cpu"
  26. - reg:
  27. Usage: required
  28. Value type: <prop-encoded-array>
  29. Definition: the first element specifies the base address and size of
  30. the register region. An optional second element specifies
  31. the base address and size of the alias register region.
  32. - regulator:
  33. Usage: optional
  34. Value type: boolean
  35. Definition: Indicates that this SPM device acts as a regulator device
  36. device for the core (CPU or Cache) the SPM is attached
  37. to.
  38. Example 1:
  39. power-controller@2099000 {
  40. compatible = "qcom,saw2";
  41. reg = <0x02099000 0x1000>, <0x02009000 0x1000>;
  42. regulator;
  43. };
  44. Example 2:
  45. saw0: power-controller@f9089000 {
  46. compatible = "qcom,apq8084-saw2-v2.1-cpu", "qcom,saw2";
  47. reg = <0xf9089000 0x1000>, <0xf9009000 0x1000>;
  48. };