[linux-2.6-block.git] / include / asm-mips / cmpxchg.h

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2003, 06, 07 by Ralf Baechle (ralf@linux-mips.org)
 */
#ifndef __ASM_CMPXCHG_H
#define __ASM_CMPXCHG_H

#include <linux/irqflags.h>

#define __HAVE_ARCH_CMPXCHG 1

#define __cmpxchg_asm(ld, st, m, old, new)				\
({									\
	__typeof(*(m)) __ret;						\
									\
	if (cpu_has_llsc && R10000_LLSC_WAR) {				\
		__asm__ __volatile__(					\
		"	.set	push				\n"	\
		"	.set	noat				\n"	\
		"	.set	mips3				\n"	\
		"1:	" ld "	%0, %2		# __cmpxchg_asm	\n"	\
		"	bne	%0, %z3, 2f			\n"	\
		"	.set	mips0				\n"	\
		"	move	$1, %z4				\n"	\
		"	.set	mips3				\n"	\
		"	" st "	$1, %1				\n"	\
		"	beqzl	$1, 1b				\n"	\
		"2:						\n"	\
		"	.set	pop				\n"	\
		: "=&r" (__ret), "=R" (*m)				\
		: "R" (*m), "Jr" (old), "Jr" (new)			\
		: "memory");						\
	} else if (cpu_has_llsc) {					\
		__asm__ __volatile__(					\
		"	.set	push				\n"	\
		"	.set	noat				\n"	\
		"	.set	mips3				\n"	\
		"1:	" ld "	%0, %2		# __cmpxchg_asm	\n"	\
		"	bne	%0, %z3, 2f			\n"	\
		"	.set	mips0				\n"	\
		"	move	$1, %z4				\n"	\
		"	.set	mips3				\n"	\
		"	" st "	$1, %1				\n"	\
		"	beqz	$1, 3f				\n"	\
		"2:						\n"	\
		"	.subsection 2				\n"	\
		"3:	b	1b				\n"	\
		"	.previous				\n"	\
		"	.set	pop				\n"	\
		: "=&r" (__ret), "=R" (*m)				\
		: "R" (*m), "Jr" (old), "Jr" (new)			\
		: "memory");						\
	} else {							\
		unsigned long __flags;					\
									\
		raw_local_irq_save(__flags);				\
		__ret = *m;						\
		if (__ret == old)					\
			*m = new;					\
		raw_local_irq_restore(__flags);				\
	}								\
									\
	__ret;								\
})

/*
 * This function doesn't exist, so you'll get a linker error
 * if something tries to do an invalid cmpxchg().
 */
extern void __cmpxchg_called_with_bad_pointer(void);

#define __cmpxchg(ptr,old,new,barrier)					\
({									\
	__typeof__(ptr) __ptr = (ptr);					\
	__typeof__(*(ptr)) __old = (old);				\
	__typeof__(*(ptr)) __new = (new);				\
	__typeof__(*(ptr)) __res = 0;					\
									\
	barrier;							\
									\
	switch (sizeof(*(__ptr))) {					\
	case 4:								\
		__res = __cmpxchg_asm("ll", "sc", __ptr, __old, __new);	\
		break;							\
	case 8:								\
		if (sizeof(long) == 8) {				\
			__res = __cmpxchg_asm("lld", "scd", __ptr,	\
					   __old, __new);		\
			break;						\
		}							\
	default:							\
		__cmpxchg_called_with_bad_pointer();			\
		break;							\
	}								\
									\
	barrier;							\
									\
	__res;								\
})

#define cmpxchg(ptr, old, new)		__cmpxchg(ptr, old, new, smp_llsc_mb())
#define cmpxchg_local(ptr, old, new)	__cmpxchg(ptr, old, new,)

#endif /* __ASM_CMPXCHG_H */
Commit	Line	Data
fef74705 RB	1	/*
	2	* This file is subject to the terms and conditions of the GNU General Public
	3	* License. See the file "COPYING" in the main directory of this archive
	4	* for more details.
	5	*
	6	* Copyright (C) 2003, 06, 07 by Ralf Baechle (ralf@linux-mips.org)
	7	*/
	8	#ifndef __ASM_CMPXCHG_H
	9	#define __ASM_CMPXCHG_H
	10
	11	#include <linux/irqflags.h>
	12
	13	#define __HAVE_ARCH_CMPXCHG 1
	14
	15	#define __cmpxchg_asm(ld, st, m, old, new) \
	16	({ \
	17	__typeof(*(m)) __ret; \
	18	\
	19	if (cpu_has_llsc && R10000_LLSC_WAR) { \
	20	__asm__ __volatile__( \
	21	" .set push \n" \
	22	" .set noat \n" \
	23	" .set mips3 \n" \
	24	"1: " ld " %0, %2 # __cmpxchg_asm \n" \
	25	" bne %0, %z3, 2f \n" \
	26	" .set mips0 \n" \
	27	" move $1, %z4 \n" \
	28	" .set mips3 \n" \
	29	" " st " $1, %1 \n" \
	30	" beqzl $1, 1b \n" \
	31	"2: \n" \
	32	" .set pop \n" \
	33	: "=&r" (__ret), "=R" (*m) \
	34	: "R" (*m), "Jr" (old), "Jr" (new) \
	35	: "memory"); \
	36	} else if (cpu_has_llsc) { \
	37	__asm__ __volatile__( \
	38	" .set push \n" \
	39	" .set noat \n" \
	40	" .set mips3 \n" \
	41	"1: " ld " %0, %2 # __cmpxchg_asm \n" \
	42	" bne %0, %z3, 2f \n" \
	43	" .set mips0 \n" \
	44	" move $1, %z4 \n" \
	45	" .set mips3 \n" \
	46	" " st " $1, %1 \n" \
	47	" beqz $1, 3f \n" \
	48	"2: \n" \
	49	" .subsection 2 \n" \
	50	"3: b 1b \n" \
	51	" .previous \n" \
	52	" .set pop \n" \
	53	: "=&r" (__ret), "=R" (*m) \
	54	: "R" (*m), "Jr" (old), "Jr" (new) \
	55	: "memory"); \
	56	} else { \
	57	unsigned long __flags; \
	58	\
	59	raw_local_irq_save(__flags); \
	60	__ret = *m; \
	61	if (__ret == old) \
	62	*m = new; \
	63	raw_local_irq_restore(__flags); \
	64	} \
65	\
66	__ret; \
67	})
68
69	/*
70	* This function doesn't exist, so you'll get a linker error
71	* if something tries to do an invalid cmpxchg().
72	*/
73	extern void __cmpxchg_called_with_bad_pointer(void);
74
75	#define __cmpxchg(ptr,old,new,barrier) \
76	({ \
77	__typeof__(ptr) __ptr = (ptr); \
78	__typeof__(*(ptr)) __old = (old); \
79	__typeof__(*(ptr)) __new = (new); \
80	__typeof__(*(ptr)) __res = 0; \
81	\
82	barrier; \
83	\
84	switch (sizeof(*(__ptr))) { \
85	case 4: \
86	__res = __cmpxchg_asm("ll", "sc", __ptr, __old, __new); \
87	break; \
88	case 8: \
89	if (sizeof(long) == 8) { \
90	__res = __cmpxchg_asm("lld", "scd", __ptr, \
91	__old, __new); \
92	break; \
93	} \
94	default: \
95	__cmpxchg_called_with_bad_pointer(); \
96	break; \
97	} \
98	\
99	barrier; \
100	\
101	__res; \
102	})
103
104	#define cmpxchg(ptr, old, new) __cmpxchg(ptr, old, new, smp_llsc_mb())
105	#define cmpxchg_local(ptr, old, new) __cmpxchg(ptr, old, new,)
106
107	#endif /* __ASM_CMPXCHG_H */