xref: /kvm-unit-tests/lib/arm/asm/bitops.h (revision 6ed97c50871a0d85e9ef5e1f4da96bc4263b4b97)
1 #ifndef _ASMARM_BITOPS_H_
2 #define _ASMARM_BITOPS_H_
3 /*
4  * Adapated from
5  *   arch/arm/lib/bitops.h
6  *
7  * Copyright (C) 2015, Red Hat Inc, Andrew Jones <drjones@redhat.com>
8  *
9  * This work is licensed under the terms of the GNU LGPL, version 2.
10  */
11 
12 #ifndef _BITOPS_H_
13 #error only <bitops.h> can be included directly
14 #endif
15 
16 #define BITS_PER_LONG	32
17 
18 #define ATOMIC_BITOP(insn, mask, word)				\
19 ({								\
20 	unsigned long tmp1, tmp2;				\
21 	asm volatile(						\
22 	"1:	ldrex	%0, [%2]\n"				\
23 		insn"	%0, %0, %3\n"				\
24 	"	strex	%1, %0, [%2]\n"				\
25 	"	cmp	%1, #0\n"				\
26 	"	bne	1b\n"					\
27 	: "=&r" (tmp1), "=&r" (tmp2)				\
28 	: "r" (word), "r" (mask)				\
29 	: "cc");						\
30 })
31 
32 #define ATOMIC_TESTOP(insn, mask, word, old)			\
33 ({								\
34 	unsigned long tmp1, tmp2;				\
35 	asm volatile(						\
36 	"1:	ldrex	%0, [%3]\n"				\
37 	"	and	%1, %0, %4\n"				\
38 		insn"	%0, %0, %4\n"				\
39 	"	strex	%2, %0, [%3]\n"				\
40 	"	cmp	%2, #0\n"				\
41 	"	bne	1b\n"					\
42 	: "=&r" (tmp1), "=&r" (old), "=&r" (tmp2)		\
43 	: "r" (word), "r" (mask)				\
44 	: "cc");						\
45 })
46 
47 extern void set_bit(int nr, volatile unsigned long *addr);
48 extern void clear_bit(int nr, volatile unsigned long *addr);
49 extern int test_bit(int nr, const volatile unsigned long *addr);
50 extern int test_and_set_bit(int nr, volatile unsigned long *addr);
51 extern int test_and_clear_bit(int nr, volatile unsigned long *addr);
52 
53 #endif /* _ASMARM_BITOPS_H_ */
54