bindings-localbus.txt 2.0 KB

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  1. $FreeBSD$
  2. Marvell Device bus (localbus) configuration.
  3. ============================================
  4. 1. Properties for localbus nodes
  5. 1.1 ranges
  6. Property: ranges
  7. Value type: <prop-encoded-array> encoded as arbitrary number of localbus
  8. nodes specifiers.
  9. Description: ranges property defines values used for mapping devices
  10. connected to localbus, in Marvell devices it is used also for
  11. setting decoding windows.
  12. a) child node address-cells:
  13. - first cell: number of bank (chip select)
  14. - second cell: (Marvell devices) Target ID for decoding
  15. windows setup
  16. b) parent node address cells:
  17. - address offset: used with parent's node base address to
  18. specify base address of mapped device
  19. c) child node size-cells:
  20. - size: defines amount of memory that should be reserved for
  21. device
  22. 1.2 bank-count
  23. Property: bank-count
  24. Value type: <u32>
  25. Description: The bank_count property defines maximum number of banks on
  26. localbus node. Bank is most often interpreted as device chip
  27. select, but may also describe another device (e.g. SPI flash).
  28. 1.3 Example
  29. localbus@0 {
  30. #address-cells = <2>;
  31. #size-cells = <1>;
  32. compatible = "mrvl,lbc";
  33. bank-count = <5>;
  34. /* This reflects CPU decode windows setup. */
  35. ranges = <0x0 0x2f 0xb2200000 0x00100000
  36. 0x1 0x3e 0xb2100000 0x00100000
  37. 0x2 0x3d 0xb0000000 0x02000000
  38. 0x3 0x3b 0xb2000000 0x00100000>;
  39. };
  40. 2. Properties for localbus consumer nodes:
  41. 2.1 reg
  42. Property: reg
  43. Value type: <prop-encoded-array>
  44. Description: A standard property required for localbus child nodes. Defines
  45. the device memory region.
  46. a) first cell: number of bank (chip select)
  47. b) address offset: used with address offset from parent's ranges
  48. for corresponding bank to specify base address of
  49. the device
  50. c) size: defines size of the device memory region
  51. 2.2 Example
  52. nor@0,0 {
  53. #address-cells = <1>;
  54. #size-cells = <1>;
  55. compatible = "cfi-flash";
  56. reg = <0x0 0x0 0x00100000>;
  57. };