bitops.h 1.1 KB

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  1. /* SPDX-License-Identifier: GPL-2.0-only */
  2. /* -*- linux-c -*- ------------------------------------------------------- *
  3. *
  4. * Copyright (C) 1991, 1992 Linus Torvalds
  5. * Copyright 2007 rPath, Inc. - All Rights Reserved
  6. *
  7. * ----------------------------------------------------------------------- */
  8. /*
  9. * Very simple bitops for the boot code.
  10. */
  11. #ifndef BOOT_BITOPS_H
  12. #define BOOT_BITOPS_H
  13. #define _LINUX_BITOPS_H /* Inhibit inclusion of <linux/bitops.h> */
  14. #include <linux/types.h>
  15. #include <asm/asm.h>
  16. static inline bool constant_test_bit(int nr, const void *addr)
  17. {
  18. const u32 *p = addr;
  19. return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0;
  20. }
  21. static inline bool variable_test_bit(int nr, const void *addr)
  22. {
  23. bool v;
  24. const u32 *p = addr;
  25. asm("btl %2,%1" CC_SET(c) : CC_OUT(c) (v) : "m" (*p), "Ir" (nr));
  26. return v;
  27. }
  28. #define test_bit(nr,addr) \
  29. (__builtin_constant_p(nr) ? \
  30. constant_test_bit((nr),(addr)) : \
  31. variable_test_bit((nr),(addr)))
  32. static inline void set_bit(int nr, void *addr)
  33. {
  34. asm("btsl %1,%0" : "+m" (*(u32 *)addr) : "Ir" (nr));
  35. }
  36. #endif /* BOOT_BITOPS_H */