xref: /openbmc/linux/arch/x86/boot/bitops.h (revision 842ed298)
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 /*
10  * Very simple bitops for the boot code.
11  */
12 
13 #ifndef BOOT_BITOPS_H
14 #define BOOT_BITOPS_H
15 #define _LINUX_BITOPS_H		/* Inhibit inclusion of <linux/bitops.h> */
16 
17 #include <linux/types.h>
18 #include <asm/asm.h>
19 
20 static inline bool constant_test_bit(int nr, const void *addr)
21 {
22 	const u32 *p = (const u32 *)addr;
23 	return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0;
24 }
25 static inline bool variable_test_bit(int nr, const void *addr)
26 {
27 	bool v;
28 	const u32 *p = (const u32 *)addr;
29 
30 	asm("btl %2,%1" CC_SET(c) : CC_OUT(c) (v) : "m" (*p), "Ir" (nr));
31 	return v;
32 }
33 
34 #define test_bit(nr,addr) \
35 (__builtin_constant_p(nr) ? \
36  constant_test_bit((nr),(addr)) : \
37  variable_test_bit((nr),(addr)))
38 
39 static inline void set_bit(int nr, void *addr)
40 {
41 	asm("btsl %1,%0" : "+m" (*(u32 *)addr) : "Ir" (nr));
42 }
43 
44 #endif /* BOOT_BITOPS_H */
45