Linux kernel mirror (for testing)
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1/* -*- linux-c -*- ------------------------------------------------------- *
2 *
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Copyright 2007 rPath, Inc. - All Rights Reserved
5 *
6 * This file is part of the Linux kernel, and is made available under
7 * the terms of the GNU General Public License version 2.
8 *
9 * ----------------------------------------------------------------------- */
10
11/*
12 * Very simple bitops for the boot code.
13 */
14
15#ifndef BOOT_BITOPS_H
16#define BOOT_BITOPS_H
17#define _LINUX_BITOPS_H /* Inhibit inclusion of <linux/bitops.h> */
18
19#include <linux/types.h>
20
21static inline bool constant_test_bit(int nr, const void *addr)
22{
23 const u32 *p = (const u32 *)addr;
24 return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0;
25}
26static inline bool variable_test_bit(int nr, const void *addr)
27{
28 bool v;
29 const u32 *p = (const u32 *)addr;
30
31 asm("btl %2,%1; setc %0" : "=qm" (v) : "m" (*p), "Ir" (nr));
32 return v;
33}
34
35#define test_bit(nr,addr) \
36(__builtin_constant_p(nr) ? \
37 constant_test_bit((nr),(addr)) : \
38 variable_test_bit((nr),(addr)))
39
40static inline void set_bit(int nr, void *addr)
41{
42 asm("btsl %1,%0" : "+m" (*(u32 *)addr) : "Ir" (nr));
43}
44
45#endif /* BOOT_BITOPS_H */