aboutsummaryrefslogtreecommitdiffstats
path: root/arch/m32r/include/asm/atomic.h
blob: 8ba8a0ab5d5d2f0e143b96f279dc487712d789ae (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
#ifndef _ASM_M32R_ATOMIC_H
#define _ASM_M32R_ATOMIC_H

/*
 *  linux/include/asm-m32r/atomic.h
 *
 *  M32R version:
 *    Copyright (C) 2001, 2002  Hitoshi Yamamoto
 *    Copyright (C) 2004  Hirokazu Takata <takata at linux-m32r.org>
 */

#include <linux/types.h>
#include <asm/assembler.h>
#include <asm/cmpxchg.h>
#include <asm/dcache_clear.h>
#include <asm/barrier.h>

/*
 * Atomic operations that C can't guarantee us.  Useful for
 * resource counting etc..
 */

#define ATOMIC_INIT(i)	{ (i) }

/**
 * atomic_read - read atomic variable
 * @v: pointer of type atomic_t
 *
 * Atomically reads the value of @v.
 */
#define atomic_read(v)	READ_ONCE((v)->counter)

/**
 * atomic_set - set atomic variable
 * @v: pointer of type atomic_t
 * @i: required value
 *
 * Atomically sets the value of @v to @i.
 */
#define atomic_set(v,i)	WRITE_ONCE(((v)->counter), (i))

#ifdef CONFIG_CHIP_M32700_TS1
#define __ATOMIC_CLOBBER	, "r4"
#else
#define __ATOMIC_CLOBBER
#endif

#define ATOMIC_OP(op)							\
static __inline__ void atomic_##op(int i, atomic_t *v)			\
{									\
	unsigned long flags;						\
	int result;							\
									\
	local_irq_save(flags);						\
	__asm__ __volatile__ (						\
		"# atomic_" #op "		\n\t"			\
		DCACHE_CLEAR("%0", "r4", "%1")				\
		M32R_LOCK" %0, @%1;		\n\t"			\
		#op " %0, %2;			\n\t"			\
		M32R_UNLOCK" %0, @%1;		\n\t"			\
		: "=&r" (result)					\
		: "r" (&v->counter), "r" (i)				\
		: "memory"						\
		__ATOMIC_CLOBBER					\
	);								\
	local_irq_restore(flags);					\
}									\

#define ATOMIC_OP_RETURN(op)						\
static __inline__ int atomic_##op##_return(int i, atomic_t *v)		\
{									\
	unsigned long flags;						\
	int result;							\
									\
	local_irq_save(flags);						\
	__asm__ __volatile__ (						\
		"# atomic_" #op "_return	\n\t"			\
		DCACHE_CLEAR("%0", "r4", "%1")				\
		M32R_LOCK" %0, @%1;		\n\t"			\
		#op " %0, %2;			\n\t"			\
		M32R_UNLOCK" %0, @%1;		\n\t"			\
		: "=&r" (result)					\
		: "r" (&v->counter), "r" (i)				\
		: "memory"						\
		__ATOMIC_CLOBBER					\
	);								\
	local_irq_restore(flags);					\
									\
	return result;							\
}

#define ATOMIC_FETCH_OP(op)						\
static __inline__ int atomic_fetch_##op(int i, atomic_t *v)		\
{									\
	unsigned long flags;						\
	int result, val;						\
									\
	local_irq_save(flags);						\
	__asm__ __volatile__ (						\
		"# atomic_fetch_" #op "		\n\t"			\
		DCACHE_CLEAR("%0", "r4", "%2")				\
		M32R_LOCK" %1, @%2;		\n\t"			\
		"mv %0, %1			\n\t" 			\
		#op " %1, %3;			\n\t"			\
		M32R_UNLOCK" %1, @%2;		\n\t"			\
		: "=&r" (result), "=&r" (val)				\
		: "r" (&v->counter), "r" (i)				\
		: "memory"						\
		__ATOMIC_CLOBBER					\
	);								\
	local_irq_restore(flags);					\
									\
	return result;							\
}

#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)

ATOMIC_OPS(add)
ATOMIC_OPS(sub)

#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)

#define atomic_fetch_or atomic_fetch_or

ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)

#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

/**
 * atomic_sub_and_test - subtract value from variable and test result
 * @i: integer value to subtract
 * @v: pointer of type atomic_t
 *
 * Atomically subtracts @i from @v and returns
 * true if the result is zero, or false for all
 * other cases.
 */
#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)

/**
 * atomic_inc_return - increment atomic variable and return it
 * @v: pointer of type atomic_t
 *
 * Atomically increments @v by 1 and returns the result.
 */
static __inline__ int atomic_inc_return(atomic_t *v)
{
	unsigned long flags;
	int result;

	local_irq_save(flags);
	__asm__ __volatile__ (
		"# atomic_inc_return		\n\t"
		DCACHE_CLEAR("%0", "r4", "%1")
		M32R_LOCK" %0, @%1;		\n\t"
		"addi	%0, #1;			\n\t"
		M32R_UNLOCK" %0, @%1;		\n\t"
		: "=&r" (result)
		: "r" (&v->counter)
		: "memory"
		__ATOMIC_CLOBBER
	);
	local_irq_restore(flags);

	return result;
}

/**
 * atomic_dec_return - decrement atomic variable and return it
 * @v: pointer of type atomic_t
 *
 * Atomically decrements @v by 1 and returns the result.
 */
static __inline__ int atomic_dec_return(atomic_t *v)
{
	unsigned long flags;
	int result;

	local_irq_save(flags);
	__asm__ __volatile__ (
		"# atomic_dec_return		\n\t"
		DCACHE_CLEAR("%0", "r4", "%1")
		M32R_LOCK" %0, @%1;		\n\t"
		"addi	%0, #-1;		\n\t"
		M32R_UNLOCK" %0, @%1;		\n\t"
		: "=&r" (result)
		: "r" (&v->counter)
		: "memory"
		__ATOMIC_CLOBBER
	);
	local_irq_restore(flags);

	return result;
}

/**
 * atomic_inc - increment atomic variable
 * @v: pointer of type atomic_t
 *
 * Atomically increments @v by 1.
 */
#define atomic_inc(v) ((void)atomic_inc_return(v))

/**
 * atomic_dec - decrement atomic variable
 * @v: pointer of type atomic_t
 *
 * Atomically decrements @v by 1.
 */
#define atomic_dec(v) ((void)atomic_dec_return(v))

/**
 * atomic_inc_and_test - increment and test
 * @v: pointer of type atomic_t
 *
 * Atomically increments @v by 1
 * and returns true if the result is zero, or false for all
 * other cases.
 */
#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)

/**
 * atomic_dec_and_test - decrement and test
 * @v: pointer of type atomic_t
 *
 * Atomically decrements @v by 1 and
 * returns true if the result is 0, or false for all
 * other cases.
 */
#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0)

/**
 * atomic_add_negative - add and test if negative
 * @v: pointer of type atomic_t
 * @i: integer value to add
 *
 * Atomically adds @i to @v and returns true
 * if the result is negative, or false when
 * result is greater than or equal to zero.
 */
#define atomic_add_negative(i,v) (atomic_add_return((i), (v)) < 0)

#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))

/**
 * __atomic_add_unless - add unless the number is a given value
 * @v: pointer of type atomic_t
 * @a: the amount to add to v...
 * @u: ...unless v is equal to u.
 *
 * Atomically adds @a to @v, so long as it was not @u.
 * Returns the old value of @v.
 */
static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
	int c, old;
	c = atomic_read(v);
	for (;;) {
		if (unlikely(c == (u)))
			break;
		old = atomic_cmpxchg((v), c, c + (a));
		if (likely(old == c))
			break;
		c = old;
	}
	return c;
}

#endif	/* _ASM_M32R_ATOMIC_H */