1#ifndef _ASM_M32R_CMPXCHG_H
  2#define _ASM_M32R_CMPXCHG_H
  3
  4/*
  5 *  M32R version:
  6 *    Copyright (C) 2001, 2002  Hitoshi Yamamoto
  7 *    Copyright (C) 2004  Hirokazu Takata <takata at linux-m32r.org>
  8 */
  9
 10#include <linux/irqflags.h>
 11#include <asm/assembler.h>
 12#include <asm/dcache_clear.h>
 13
 14extern void  __xchg_called_with_bad_pointer(void);
 15
 16static __always_inline unsigned long
 17__xchg(unsigned long x, volatile void *ptr, int size)
 18{
 19	unsigned long flags;
 20	unsigned long tmp = 0;
 21
 22	local_irq_save(flags);
 23
 24	switch (size) {
 25#ifndef CONFIG_SMP
 26	case 1:
 27		__asm__ __volatile__ (
 28			"ldb	%0, @%2 \n\t"
 29			"stb	%1, @%2 \n\t"
 30			: "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");
 31		break;
 32	case 2:
 33		__asm__ __volatile__ (
 34			"ldh	%0, @%2 \n\t"
 35			"sth	%1, @%2 \n\t"
 36			: "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");
 37		break;
 38	case 4:
 39		__asm__ __volatile__ (
 40			"ld	%0, @%2 \n\t"
 41			"st	%1, @%2 \n\t"
 42			: "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");
 43		break;
 44#else  /* CONFIG_SMP */
 45	case 4:
 46		__asm__ __volatile__ (
 47			DCACHE_CLEAR("%0", "r4", "%2")
 48			"lock	%0, @%2;	\n\t"
 49			"unlock	%1, @%2;	\n\t"
 50			: "=&r" (tmp) : "r" (x), "r" (ptr)
 51			: "memory"
 52#ifdef CONFIG_CHIP_M32700_TS1
 53			, "r4"
 54#endif	/* CONFIG_CHIP_M32700_TS1 */
 55		);
 56		break;
 57#endif  /* CONFIG_SMP */
 58	default:
 59		__xchg_called_with_bad_pointer();
 60	}
 61
 62	local_irq_restore(flags);
 63
 64	return (tmp);
 65}
 66
 67#define xchg(ptr, x)							\
 68	((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
 69
 70static __always_inline unsigned long
 71__xchg_local(unsigned long x, volatile void *ptr, int size)
 72{
 73	unsigned long flags;
 74	unsigned long tmp = 0;
 75
 76	local_irq_save(flags);
 77
 78	switch (size) {
 79	case 1:
 80		__asm__ __volatile__ (
 81			"ldb	%0, @%2 \n\t"
 82			"stb	%1, @%2 \n\t"
 83			: "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");
 84		break;
 85	case 2:
 86		__asm__ __volatile__ (
 87			"ldh	%0, @%2 \n\t"
 88			"sth	%1, @%2 \n\t"
 89			: "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");
 90		break;
 91	case 4:
 92		__asm__ __volatile__ (
 93			"ld	%0, @%2 \n\t"
 94			"st	%1, @%2 \n\t"
 95			: "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");
 96		break;
 97	default:
 98		__xchg_called_with_bad_pointer();
 99	}
100
101	local_irq_restore(flags);
102
103	return (tmp);
104}
105
106#define xchg_local(ptr, x)						\
107	((__typeof__(*(ptr)))__xchg_local((unsigned long)(x), (ptr),	\
108			sizeof(*(ptr))))
109
110static inline unsigned long
111__cmpxchg_u32(volatile unsigned int *p, unsigned int old, unsigned int new)
112{
113	unsigned long flags;
114	unsigned int retval;
115
116	local_irq_save(flags);
117	__asm__ __volatile__ (
118			DCACHE_CLEAR("%0", "r4", "%1")
119			M32R_LOCK" %0, @%1;	\n"
120		"	bne	%0, %2, 1f;	\n"
121			M32R_UNLOCK" %3, @%1;	\n"
122		"	bra	2f;		\n"
123                "       .fillinsn		\n"
124		"1:"
125			M32R_UNLOCK" %0, @%1;	\n"
126                "       .fillinsn		\n"
127		"2:"
128			: "=&r" (retval)
129			: "r" (p), "r" (old), "r" (new)
130			: "cbit", "memory"
131#ifdef CONFIG_CHIP_M32700_TS1
132			, "r4"
133#endif  /* CONFIG_CHIP_M32700_TS1 */
134		);
135	local_irq_restore(flags);
136
137	return retval;
138}
139
140static inline unsigned long
141__cmpxchg_local_u32(volatile unsigned int *p, unsigned int old,
142			unsigned int new)
143{
144	unsigned long flags;
145	unsigned int retval;
146
147	local_irq_save(flags);
148	__asm__ __volatile__ (
149			DCACHE_CLEAR("%0", "r4", "%1")
150			"ld %0, @%1;		\n"
151		"	bne	%0, %2, 1f;	\n"
152			"st %3, @%1;		\n"
153		"	bra	2f;		\n"
154		"       .fillinsn		\n"
155		"1:"
156			"st %0, @%1;		\n"
157		"       .fillinsn		\n"
158		"2:"
159			: "=&r" (retval)
160			: "r" (p), "r" (old), "r" (new)
161			: "cbit", "memory"
162#ifdef CONFIG_CHIP_M32700_TS1
163			, "r4"
164#endif  /* CONFIG_CHIP_M32700_TS1 */
165		);
166	local_irq_restore(flags);
167
168	return retval;
169}
170
171/* This function doesn't exist, so you'll get a linker error
172   if something tries to do an invalid cmpxchg().  */
173extern void __cmpxchg_called_with_bad_pointer(void);
174
175static inline unsigned long
176__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
177{
178	switch (size) {
179	case 4:
180		return __cmpxchg_u32(ptr, old, new);
181#if 0	/* we don't have __cmpxchg_u64 */
182	case 8:
183		return __cmpxchg_u64(ptr, old, new);
184#endif /* 0 */
185	}
186	__cmpxchg_called_with_bad_pointer();
187	return old;
188}
189
190#define cmpxchg(ptr, o, n)						 \
191	((__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)(o),	 \
192			(unsigned long)(n), sizeof(*(ptr))))
193
194#include <asm-generic/cmpxchg-local.h>
195
196static inline unsigned long __cmpxchg_local(volatile void *ptr,
197				      unsigned long old,
198				      unsigned long new, int size)
199{
200	switch (size) {
201	case 4:
202		return __cmpxchg_local_u32(ptr, old, new);
203	default:
204		return __cmpxchg_local_generic(ptr, old, new, size);
205	}
206
207	return old;
208}
209
210/*
211 * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
212 * them available.
213 */
214#define cmpxchg_local(ptr, o, n)				  	    \
215	((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o),	    \
216			(unsigned long)(n), sizeof(*(ptr))))
217#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
218
219#endif /* _ASM_M32R_CMPXCHG_H */