watchdog.h 1.6 KB

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  1. /* SPDX-License-Identifier: GPL-2.0
  2. *
  3. * include/asm-sh/cpu-sh2/watchdog.h
  4. *
  5. * Copyright (C) 2002, 2003 Paul Mundt
  6. */
  7. #ifndef __ASM_CPU_SH2_WATCHDOG_H
  8. #define __ASM_CPU_SH2_WATCHDOG_H
  9. /*
  10. * More SH-2 brilliance .. its not good enough that we can't read
  11. * and write the same sizes to WTCNT, now we have to read and write
  12. * with different sizes at different addresses for WTCNT _and_ RSTCSR.
  13. *
  14. * At least on the bright side no one has managed to screw over WTCSR
  15. * in this fashion .. yet.
  16. */
  17. /* Register definitions */
  18. #define WTCNT 0xfffffe80
  19. #define WTCSR 0xfffffe80
  20. #define RSTCSR 0xfffffe82
  21. #define WTCNT_R (WTCNT + 1)
  22. #define RSTCSR_R (RSTCSR + 1)
  23. /* Bit definitions */
  24. #define WTCSR_IOVF 0x80
  25. #define WTCSR_WT 0x40
  26. #define WTCSR_TME 0x20
  27. #define WTCSR_RSTS 0x00
  28. #define RSTCSR_RSTS 0x20
  29. /**
  30. * sh_wdt_read_rstcsr - Read from Reset Control/Status Register
  31. *
  32. * Reads back the RSTCSR value.
  33. */
  34. static inline __u8 sh_wdt_read_rstcsr(void)
  35. {
  36. /*
  37. * Same read/write brain-damage as for WTCNT here..
  38. */
  39. return __raw_readb(RSTCSR_R);
  40. }
  41. /**
  42. * sh_wdt_write_csr - Write to Reset Control/Status Register
  43. *
  44. * @val: Value to write
  45. *
  46. * Writes the given value @val to the lower byte of the control/status
  47. * register. The upper byte is set manually on each write.
  48. */
  49. static inline void sh_wdt_write_rstcsr(__u8 val)
  50. {
  51. /*
  52. * Note: Due to the brain-damaged nature of this register,
  53. * we can't presently touch the WOVF bit, since the upper byte
  54. * has to be swapped for this. So just leave it alone..
  55. */
  56. __raw_writeb((WTCNT_HIGH << 8) | (__u16)val, RSTCSR);
  57. }
  58. #endif /* __ASM_CPU_SH2_WATCHDOG_H */