1#ifndef _ASM_IA64_CMPXCHG_H
  2#define _ASM_IA64_CMPXCHG_H
  3
  4/*
  5 * Compare/Exchange, forked from asm/intrinsics.h
  6 * which was:
  7 *
  8 *	Copyright (C) 2002-2003 Hewlett-Packard Co
  9 *	David Mosberger-Tang <davidm@hpl.hp.com>
 10 */
 11
 12#ifndef __ASSEMBLY__
 13
 14#include <linux/types.h>
 15/* include compiler specific intrinsics */
 16#include <asm/ia64regs.h>
 17#ifdef __INTEL_COMPILER
 18# include <asm/intel_intrin.h>
 19#else
 20# include <asm/gcc_intrin.h>
 21#endif
 22
 23/*
 24 * This function doesn't exist, so you'll get a linker error if
 25 * something tries to do an invalid xchg().
 26 */
 27extern void ia64_xchg_called_with_bad_pointer(void);
 28
 29#define __xchg(x, ptr, size)						\
 30({									\
 31	unsigned long __xchg_result;					\
 32									\
 33	switch (size) {							\
 34	case 1:								\
 35		__xchg_result = ia64_xchg1((__u8 *)ptr, x);		\
 36		break;							\
 37									\
 38	case 2:								\
 39		__xchg_result = ia64_xchg2((__u16 *)ptr, x);		\
 40		break;							\
 41									\
 42	case 4:								\
 43		__xchg_result = ia64_xchg4((__u32 *)ptr, x);		\
 44		break;							\
 45									\
 46	case 8:								\
 47		__xchg_result = ia64_xchg8((__u64 *)ptr, x);		\
 48		break;							\
 49	default:							\
 50		ia64_xchg_called_with_bad_pointer();			\
 51	}								\
 52	__xchg_result;							\
 53})
 54
 55#define xchg(ptr, x)							\
 56((__typeof__(*(ptr))) __xchg((unsigned long) (x), (ptr), sizeof(*(ptr))))
 57
 58/*
 59 * Atomic compare and exchange.  Compare OLD with MEM, if identical,
 60 * store NEW in MEM.  Return the initial value in MEM.  Success is
 61 * indicated by comparing RETURN with OLD.
 62 */
 63
 64#define __HAVE_ARCH_CMPXCHG 1
 65
 66/*
 67 * This function doesn't exist, so you'll get a linker error
 68 * if something tries to do an invalid cmpxchg().
 69 */
 70extern long ia64_cmpxchg_called_with_bad_pointer(void);
 71
 72#define ia64_cmpxchg(sem, ptr, old, new, size)				\
 73({									\
 74	__u64 _o_, _r_;							\
 75									\
 76	switch (size) {							\
 77	case 1:								\
 78		_o_ = (__u8) (long) (old);				\
 79		break;							\
 80	case 2:								\
 81		_o_ = (__u16) (long) (old);				\
 82		break;							\
 83	case 4:								\
 84		_o_ = (__u32) (long) (old);				\
 85		break;							\
 86	case 8:								\
 87		_o_ = (__u64) (long) (old);				\
 88		break;							\
 89	default:							\
 90		break;							\
 91	}								\
 92	switch (size) {							\
 93	case 1:								\
 94		_r_ = ia64_cmpxchg1_##sem((__u8 *) ptr, new, _o_);	\
 95		break;							\
 96									\
 97	case 2:								\
 98		_r_ = ia64_cmpxchg2_##sem((__u16 *) ptr, new, _o_);	\
 99		break;							\
100									\
101	case 4:								\
102		_r_ = ia64_cmpxchg4_##sem((__u32 *) ptr, new, _o_);	\
103		break;							\
104									\
105	case 8:								\
106		_r_ = ia64_cmpxchg8_##sem((__u64 *) ptr, new, _o_);	\
107		break;							\
108									\
109	default:							\
110		_r_ = ia64_cmpxchg_called_with_bad_pointer();		\
111		break;							\
112	}								\
113	(__typeof__(old)) _r_;						\
114})
115
116#define cmpxchg_acq(ptr, o, n)	\
117	ia64_cmpxchg(acq, (ptr), (o), (n), sizeof(*(ptr)))
118#define cmpxchg_rel(ptr, o, n)	\
119	ia64_cmpxchg(rel, (ptr), (o), (n), sizeof(*(ptr)))
120
121/* for compatibility with other platforms: */
122#define cmpxchg(ptr, o, n)	cmpxchg_acq((ptr), (o), (n))
123#define cmpxchg64(ptr, o, n)	cmpxchg_acq((ptr), (o), (n))
124
125#define cmpxchg_local		cmpxchg
126#define cmpxchg64_local		cmpxchg64
127
128#ifdef CONFIG_IA64_DEBUG_CMPXCHG
129# define CMPXCHG_BUGCHECK_DECL	int _cmpxchg_bugcheck_count = 128;
130# define CMPXCHG_BUGCHECK(v)						\
131do {									\
132	if (_cmpxchg_bugcheck_count-- <= 0) {				\
133		void *ip;						\
134		extern int printk(const char *fmt, ...);		\
135		ip = (void *) ia64_getreg(_IA64_REG_IP);		\
136		printk("CMPXCHG_BUGCHECK: stuck at %p on word %p\n", ip, (v));\
137		break;							\
138	}								\
139} while (0)
140#else /* !CONFIG_IA64_DEBUG_CMPXCHG */
141# define CMPXCHG_BUGCHECK_DECL
142# define CMPXCHG_BUGCHECK(v)
143#endif /* !CONFIG_IA64_DEBUG_CMPXCHG */
144
145#endif /* !__ASSEMBLY__ */
146
147#endif /* _ASM_IA64_CMPXCHG_H */