syscon-reset.txt 1.1 KB

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  1. Generic SYSCON mapped register reset driver
  2. This is a generic reset driver using syscon to map the reset register.
  3. The reset is generally performed with a write to the reset register
  4. defined by the register map pointed by syscon reference plus the offset and
  5. shifted by the reset specifier/
  6. To assert a reset on some device, the equivalent of the following operation is
  7. performed, where reset_id is the reset specifier from the device's resets
  8. property.
  9. if (BIT(reset_id) & mask)
  10. regmap[offset][reset_id] = assert-high;
  11. Required properties:
  12. - compatible: should contain "syscon-reset"
  13. - #reset-cells: must be 1
  14. - regmap: this is phandle to the register map node
  15. - offset: offset in the register map for the reboot register (in bytes)
  16. Optional properties:
  17. - mask: accept only the reset specifiers defined by the mask (32 bit)
  18. - assert-high: Bit to write when asserting a reset. Defaults to 1.
  19. Default will be little endian mode, 32 bit access only.
  20. Example:
  21. reset-controller {
  22. compatible = "syscon-reset";
  23. #reset-cells = <1>;
  24. regmap = <&sysctl>;
  25. offset = <0x20>;
  26. mask = <0x27FFFFFF>;
  27. assert-high = <0>;
  28. };