1 #ifndef _ASM_M32R_ATOMIC_H
2 #define _ASM_M32R_ATOMIC_H
5 * linux/include/asm-m32r/atomic.h
8 * Copyright (C) 2001, 2002 Hitoshi Yamamoto
9 * Copyright (C) 2004 Hirokazu Takata <takata at linux-m32r.org>
12 #include <linux/types.h>
13 #include <asm/assembler.h>
14 #include <asm/cmpxchg.h>
15 #include <asm/dcache_clear.h>
16 #include <asm/barrier.h>
19 * Atomic operations that C can't guarantee us. Useful for
20 * resource counting etc..
23 #define ATOMIC_INIT(i) { (i) }
26 * atomic_read - read atomic variable
27 * @v: pointer of type atomic_t
29 * Atomically reads the value of @v.
31 #define atomic_read(v) ACCESS_ONCE((v)->counter)
34 * atomic_set - set atomic variable
35 * @v: pointer of type atomic_t
38 * Atomically sets the value of @v to @i.
40 #define atomic_set(v,i) (((v)->counter) = (i))
42 #ifdef CONFIG_CHIP_M32700_TS1
43 #define __ATOMIC_CLOBBER , "r4"
45 #define __ATOMIC_CLOBBER
48 #define ATOMIC_OP(op) \
49 static __inline__ void atomic_##op(int i, atomic_t *v) \
51 unsigned long flags; \
54 local_irq_save(flags); \
55 __asm__ __volatile__ ( \
56 "# atomic_" #op " \n\t" \
57 DCACHE_CLEAR("%0", "r4", "%1") \
58 M32R_LOCK" %0, @%1; \n\t" \
60 M32R_UNLOCK" %0, @%1; \n\t" \
62 : "r" (&v->counter), "r" (i) \
66 local_irq_restore(flags); \
69 #define ATOMIC_OP_RETURN(op) \
70 static __inline__ int atomic_##op##_return(int i, atomic_t *v) \
72 unsigned long flags; \
75 local_irq_save(flags); \
76 __asm__ __volatile__ ( \
77 "# atomic_" #op "_return \n\t" \
78 DCACHE_CLEAR("%0", "r4", "%1") \
79 M32R_LOCK" %0, @%1; \n\t" \
81 M32R_UNLOCK" %0, @%1; \n\t" \
83 : "r" (&v->counter), "r" (i) \
87 local_irq_restore(flags); \
92 #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
98 #undef ATOMIC_OP_RETURN
102 * atomic_sub_and_test - subtract value from variable and test result
103 * @i: integer value to subtract
104 * @v: pointer of type atomic_t
106 * Atomically subtracts @i from @v and returns
107 * true if the result is zero, or false for all
110 #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
113 * atomic_inc_return - increment atomic variable and return it
114 * @v: pointer of type atomic_t
116 * Atomically increments @v by 1 and returns the result.
118 static __inline__ int atomic_inc_return(atomic_t *v)
123 local_irq_save(flags);
124 __asm__ __volatile__ (
125 "# atomic_inc_return \n\t"
126 DCACHE_CLEAR("%0", "r4", "%1")
127 M32R_LOCK" %0, @%1; \n\t"
129 M32R_UNLOCK" %0, @%1; \n\t"
135 local_irq_restore(flags);
141 * atomic_dec_return - decrement atomic variable and return it
142 * @v: pointer of type atomic_t
144 * Atomically decrements @v by 1 and returns the result.
146 static __inline__ int atomic_dec_return(atomic_t *v)
151 local_irq_save(flags);
152 __asm__ __volatile__ (
153 "# atomic_dec_return \n\t"
154 DCACHE_CLEAR("%0", "r4", "%1")
155 M32R_LOCK" %0, @%1; \n\t"
157 M32R_UNLOCK" %0, @%1; \n\t"
163 local_irq_restore(flags);
169 * atomic_inc - increment atomic variable
170 * @v: pointer of type atomic_t
172 * Atomically increments @v by 1.
174 #define atomic_inc(v) ((void)atomic_inc_return(v))
177 * atomic_dec - decrement atomic variable
178 * @v: pointer of type atomic_t
180 * Atomically decrements @v by 1.
182 #define atomic_dec(v) ((void)atomic_dec_return(v))
185 * atomic_inc_and_test - increment and test
186 * @v: pointer of type atomic_t
188 * Atomically increments @v by 1
189 * and returns true if the result is zero, or false for all
192 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
195 * atomic_dec_and_test - decrement and test
196 * @v: pointer of type atomic_t
198 * Atomically decrements @v by 1 and
199 * returns true if the result is 0, or false for all
202 #define atomic_dec_and_test(v) (atomic_dec_return(v) == 0)
205 * atomic_add_negative - add and test if negative
206 * @v: pointer of type atomic_t
207 * @i: integer value to add
209 * Atomically adds @i to @v and returns true
210 * if the result is negative, or false when
211 * result is greater than or equal to zero.
213 #define atomic_add_negative(i,v) (atomic_add_return((i), (v)) < 0)
215 #define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
216 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
219 * __atomic_add_unless - add unless the number is a given value
220 * @v: pointer of type atomic_t
221 * @a: the amount to add to v...
222 * @u: ...unless v is equal to u.
224 * Atomically adds @a to @v, so long as it was not @u.
225 * Returns the old value of @v.
227 static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
232 if (unlikely(c == (u)))
234 old = atomic_cmpxchg((v), c, c + (a));
235 if (likely(old == c))
243 static __inline__ void atomic_clear_mask(unsigned long mask, atomic_t *addr)
248 local_irq_save(flags);
249 __asm__ __volatile__ (
250 "# atomic_clear_mask \n\t"
251 DCACHE_CLEAR("%0", "r5", "%1")
252 M32R_LOCK" %0, @%1; \n\t"
254 M32R_UNLOCK" %0, @%1; \n\t"
256 : "r" (addr), "r" (~mask)
260 local_irq_restore(flags);
263 static __inline__ void atomic_set_mask(unsigned long mask, atomic_t *addr)
268 local_irq_save(flags);
269 __asm__ __volatile__ (
270 "# atomic_set_mask \n\t"
271 DCACHE_CLEAR("%0", "r5", "%1")
272 M32R_LOCK" %0, @%1; \n\t"
274 M32R_UNLOCK" %0, @%1; \n\t"
276 : "r" (addr), "r" (mask)
280 local_irq_restore(flags);
283 #endif /* _ASM_M32R_ATOMIC_H */