1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright IBM Corp. 1999, 2011
4 *
5 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
6 */
7
8#ifndef __ASM_CMPXCHG_H
9#define __ASM_CMPXCHG_H
10
11#include <linux/mmdebug.h>
12#include <linux/types.h>
13#include <linux/bug.h>
14
15#define cmpxchg(ptr, o, n)						\
16({									\
17	__typeof__(*(ptr)) __o = (o);					\
18	__typeof__(*(ptr)) __n = (n);					\
19	(__typeof__(*(ptr))) __sync_val_compare_and_swap((ptr),__o,__n);\
20})
21
22#define cmpxchg64	cmpxchg
23#define cmpxchg_local	cmpxchg
24#define cmpxchg64_local	cmpxchg
25
26#define xchg(ptr, x)							\
27({									\
28	__typeof__(ptr) __ptr = (ptr);					\
29	__typeof__(*(ptr)) __old;					\
30	do {								\
31		__old = *__ptr;						\
32	} while (!__sync_bool_compare_and_swap(__ptr, __old, x));	\
33	__old;								\
34})
35
36#define __cmpxchg_double(p1, p2, o1, o2, n1, n2)			\
37({									\
38	register __typeof__(*(p1)) __old1 asm("2") = (o1);		\
39	register __typeof__(*(p2)) __old2 asm("3") = (o2);		\
40	register __typeof__(*(p1)) __new1 asm("4") = (n1);		\
41	register __typeof__(*(p2)) __new2 asm("5") = (n2);		\
42	int cc;								\
43	asm volatile(							\
44		"	cdsg	%[old],%[new],%[ptr]\n"			\
45		"	ipm	%[cc]\n"				\
46		"	srl	%[cc],28"				\
47		: [cc] "=d" (cc), [old] "+d" (__old1), "+d" (__old2)	\
48		: [new] "d" (__new1), "d" (__new2),			\
49		  [ptr] "Q" (*(p1)), "Q" (*(p2))			\
50		: "memory", "cc");					\
51	!cc;								\
52})
53
54#define cmpxchg_double(p1, p2, o1, o2, n1, n2)				\
55({									\
56	__typeof__(p1) __p1 = (p1);					\
57	__typeof__(p2) __p2 = (p2);					\
58	BUILD_BUG_ON(sizeof(*(p1)) != sizeof(long));			\
59	BUILD_BUG_ON(sizeof(*(p2)) != sizeof(long));			\
60	VM_BUG_ON((unsigned long)((__p1) + 1) != (unsigned long)(__p2));\
61	__cmpxchg_double(__p1, __p2, o1, o2, n1, n2);			\
62})
63
64#define system_has_cmpxchg_double()	1
65
66#endif /* __ASM_CMPXCHG_H */
67