xref: /openbmc/linux/arch/x86/boot/bitops.h (revision e2c75e76)
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 
21 static 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 }
26 static 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 
40 static 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 */
46