xref: /openbmc/linux/arch/powerpc/include/asm/atomic.h (revision a09d2831)
1 #ifndef _ASM_POWERPC_ATOMIC_H_
2 #define _ASM_POWERPC_ATOMIC_H_
3 
4 /*
5  * PowerPC atomic operations
6  */
7 
8 #include <linux/types.h>
9 
10 #ifdef __KERNEL__
11 #include <linux/compiler.h>
12 #include <asm/synch.h>
13 #include <asm/asm-compat.h>
14 #include <asm/system.h>
15 
16 #define ATOMIC_INIT(i)		{ (i) }
17 
18 static __inline__ int atomic_read(const atomic_t *v)
19 {
20 	int t;
21 
22 	__asm__ __volatile__("lwz%U1%X1 %0,%1" : "=r"(t) : "m"(v->counter));
23 
24 	return t;
25 }
26 
27 static __inline__ void atomic_set(atomic_t *v, int i)
28 {
29 	__asm__ __volatile__("stw%U0%X0 %1,%0" : "=m"(v->counter) : "r"(i));
30 }
31 
32 static __inline__ void atomic_add(int a, atomic_t *v)
33 {
34 	int t;
35 
36 	__asm__ __volatile__(
37 "1:	lwarx	%0,0,%3		# atomic_add\n\
38 	add	%0,%2,%0\n"
39 	PPC405_ERR77(0,%3)
40 "	stwcx.	%0,0,%3 \n\
41 	bne-	1b"
42 	: "=&r" (t), "+m" (v->counter)
43 	: "r" (a), "r" (&v->counter)
44 	: "cc");
45 }
46 
47 static __inline__ int atomic_add_return(int a, atomic_t *v)
48 {
49 	int t;
50 
51 	__asm__ __volatile__(
52 	LWSYNC_ON_SMP
53 "1:	lwarx	%0,0,%2		# atomic_add_return\n\
54 	add	%0,%1,%0\n"
55 	PPC405_ERR77(0,%2)
56 "	stwcx.	%0,0,%2 \n\
57 	bne-	1b"
58 	ISYNC_ON_SMP
59 	: "=&r" (t)
60 	: "r" (a), "r" (&v->counter)
61 	: "cc", "memory");
62 
63 	return t;
64 }
65 
66 #define atomic_add_negative(a, v)	(atomic_add_return((a), (v)) < 0)
67 
68 static __inline__ void atomic_sub(int a, atomic_t *v)
69 {
70 	int t;
71 
72 	__asm__ __volatile__(
73 "1:	lwarx	%0,0,%3		# atomic_sub\n\
74 	subf	%0,%2,%0\n"
75 	PPC405_ERR77(0,%3)
76 "	stwcx.	%0,0,%3 \n\
77 	bne-	1b"
78 	: "=&r" (t), "+m" (v->counter)
79 	: "r" (a), "r" (&v->counter)
80 	: "cc");
81 }
82 
83 static __inline__ int atomic_sub_return(int a, atomic_t *v)
84 {
85 	int t;
86 
87 	__asm__ __volatile__(
88 	LWSYNC_ON_SMP
89 "1:	lwarx	%0,0,%2		# atomic_sub_return\n\
90 	subf	%0,%1,%0\n"
91 	PPC405_ERR77(0,%2)
92 "	stwcx.	%0,0,%2 \n\
93 	bne-	1b"
94 	ISYNC_ON_SMP
95 	: "=&r" (t)
96 	: "r" (a), "r" (&v->counter)
97 	: "cc", "memory");
98 
99 	return t;
100 }
101 
102 static __inline__ void atomic_inc(atomic_t *v)
103 {
104 	int t;
105 
106 	__asm__ __volatile__(
107 "1:	lwarx	%0,0,%2		# atomic_inc\n\
108 	addic	%0,%0,1\n"
109 	PPC405_ERR77(0,%2)
110 "	stwcx.	%0,0,%2 \n\
111 	bne-	1b"
112 	: "=&r" (t), "+m" (v->counter)
113 	: "r" (&v->counter)
114 	: "cc", "xer");
115 }
116 
117 static __inline__ int atomic_inc_return(atomic_t *v)
118 {
119 	int t;
120 
121 	__asm__ __volatile__(
122 	LWSYNC_ON_SMP
123 "1:	lwarx	%0,0,%1		# atomic_inc_return\n\
124 	addic	%0,%0,1\n"
125 	PPC405_ERR77(0,%1)
126 "	stwcx.	%0,0,%1 \n\
127 	bne-	1b"
128 	ISYNC_ON_SMP
129 	: "=&r" (t)
130 	: "r" (&v->counter)
131 	: "cc", "xer", "memory");
132 
133 	return t;
134 }
135 
136 /*
137  * atomic_inc_and_test - increment and test
138  * @v: pointer of type atomic_t
139  *
140  * Atomically increments @v by 1
141  * and returns true if the result is zero, or false for all
142  * other cases.
143  */
144 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
145 
146 static __inline__ void atomic_dec(atomic_t *v)
147 {
148 	int t;
149 
150 	__asm__ __volatile__(
151 "1:	lwarx	%0,0,%2		# atomic_dec\n\
152 	addic	%0,%0,-1\n"
153 	PPC405_ERR77(0,%2)\
154 "	stwcx.	%0,0,%2\n\
155 	bne-	1b"
156 	: "=&r" (t), "+m" (v->counter)
157 	: "r" (&v->counter)
158 	: "cc", "xer");
159 }
160 
161 static __inline__ int atomic_dec_return(atomic_t *v)
162 {
163 	int t;
164 
165 	__asm__ __volatile__(
166 	LWSYNC_ON_SMP
167 "1:	lwarx	%0,0,%1		# atomic_dec_return\n\
168 	addic	%0,%0,-1\n"
169 	PPC405_ERR77(0,%1)
170 "	stwcx.	%0,0,%1\n\
171 	bne-	1b"
172 	ISYNC_ON_SMP
173 	: "=&r" (t)
174 	: "r" (&v->counter)
175 	: "cc", "xer", "memory");
176 
177 	return t;
178 }
179 
180 #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
181 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
182 
183 /**
184  * atomic_add_unless - add unless the number is a given value
185  * @v: pointer of type atomic_t
186  * @a: the amount to add to v...
187  * @u: ...unless v is equal to u.
188  *
189  * Atomically adds @a to @v, so long as it was not @u.
190  * Returns non-zero if @v was not @u, and zero otherwise.
191  */
192 static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
193 {
194 	int t;
195 
196 	__asm__ __volatile__ (
197 	LWSYNC_ON_SMP
198 "1:	lwarx	%0,0,%1		# atomic_add_unless\n\
199 	cmpw	0,%0,%3 \n\
200 	beq-	2f \n\
201 	add	%0,%2,%0 \n"
202 	PPC405_ERR77(0,%2)
203 "	stwcx.	%0,0,%1 \n\
204 	bne-	1b \n"
205 	ISYNC_ON_SMP
206 "	subf	%0,%2,%0 \n\
207 2:"
208 	: "=&r" (t)
209 	: "r" (&v->counter), "r" (a), "r" (u)
210 	: "cc", "memory");
211 
212 	return t != u;
213 }
214 
215 #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
216 
217 #define atomic_sub_and_test(a, v)	(atomic_sub_return((a), (v)) == 0)
218 #define atomic_dec_and_test(v)		(atomic_dec_return((v)) == 0)
219 
220 /*
221  * Atomically test *v and decrement if it is greater than 0.
222  * The function returns the old value of *v minus 1, even if
223  * the atomic variable, v, was not decremented.
224  */
225 static __inline__ int atomic_dec_if_positive(atomic_t *v)
226 {
227 	int t;
228 
229 	__asm__ __volatile__(
230 	LWSYNC_ON_SMP
231 "1:	lwarx	%0,0,%1		# atomic_dec_if_positive\n\
232 	cmpwi	%0,1\n\
233 	addi	%0,%0,-1\n\
234 	blt-	2f\n"
235 	PPC405_ERR77(0,%1)
236 "	stwcx.	%0,0,%1\n\
237 	bne-	1b"
238 	ISYNC_ON_SMP
239 	"\n\
240 2:"	: "=&b" (t)
241 	: "r" (&v->counter)
242 	: "cc", "memory");
243 
244 	return t;
245 }
246 
247 #define smp_mb__before_atomic_dec()     smp_mb()
248 #define smp_mb__after_atomic_dec()      smp_mb()
249 #define smp_mb__before_atomic_inc()     smp_mb()
250 #define smp_mb__after_atomic_inc()      smp_mb()
251 
252 #ifdef __powerpc64__
253 
254 #define ATOMIC64_INIT(i)	{ (i) }
255 
256 static __inline__ long atomic64_read(const atomic64_t *v)
257 {
258 	long t;
259 
260 	__asm__ __volatile__("ld%U1%X1 %0,%1" : "=r"(t) : "m"(v->counter));
261 
262 	return t;
263 }
264 
265 static __inline__ void atomic64_set(atomic64_t *v, long i)
266 {
267 	__asm__ __volatile__("std%U0%X0 %1,%0" : "=m"(v->counter) : "r"(i));
268 }
269 
270 static __inline__ void atomic64_add(long a, atomic64_t *v)
271 {
272 	long t;
273 
274 	__asm__ __volatile__(
275 "1:	ldarx	%0,0,%3		# atomic64_add\n\
276 	add	%0,%2,%0\n\
277 	stdcx.	%0,0,%3 \n\
278 	bne-	1b"
279 	: "=&r" (t), "+m" (v->counter)
280 	: "r" (a), "r" (&v->counter)
281 	: "cc");
282 }
283 
284 static __inline__ long atomic64_add_return(long a, atomic64_t *v)
285 {
286 	long t;
287 
288 	__asm__ __volatile__(
289 	LWSYNC_ON_SMP
290 "1:	ldarx	%0,0,%2		# atomic64_add_return\n\
291 	add	%0,%1,%0\n\
292 	stdcx.	%0,0,%2 \n\
293 	bne-	1b"
294 	ISYNC_ON_SMP
295 	: "=&r" (t)
296 	: "r" (a), "r" (&v->counter)
297 	: "cc", "memory");
298 
299 	return t;
300 }
301 
302 #define atomic64_add_negative(a, v)	(atomic64_add_return((a), (v)) < 0)
303 
304 static __inline__ void atomic64_sub(long a, atomic64_t *v)
305 {
306 	long t;
307 
308 	__asm__ __volatile__(
309 "1:	ldarx	%0,0,%3		# atomic64_sub\n\
310 	subf	%0,%2,%0\n\
311 	stdcx.	%0,0,%3 \n\
312 	bne-	1b"
313 	: "=&r" (t), "+m" (v->counter)
314 	: "r" (a), "r" (&v->counter)
315 	: "cc");
316 }
317 
318 static __inline__ long atomic64_sub_return(long a, atomic64_t *v)
319 {
320 	long t;
321 
322 	__asm__ __volatile__(
323 	LWSYNC_ON_SMP
324 "1:	ldarx	%0,0,%2		# atomic64_sub_return\n\
325 	subf	%0,%1,%0\n\
326 	stdcx.	%0,0,%2 \n\
327 	bne-	1b"
328 	ISYNC_ON_SMP
329 	: "=&r" (t)
330 	: "r" (a), "r" (&v->counter)
331 	: "cc", "memory");
332 
333 	return t;
334 }
335 
336 static __inline__ void atomic64_inc(atomic64_t *v)
337 {
338 	long t;
339 
340 	__asm__ __volatile__(
341 "1:	ldarx	%0,0,%2		# atomic64_inc\n\
342 	addic	%0,%0,1\n\
343 	stdcx.	%0,0,%2 \n\
344 	bne-	1b"
345 	: "=&r" (t), "+m" (v->counter)
346 	: "r" (&v->counter)
347 	: "cc", "xer");
348 }
349 
350 static __inline__ long atomic64_inc_return(atomic64_t *v)
351 {
352 	long t;
353 
354 	__asm__ __volatile__(
355 	LWSYNC_ON_SMP
356 "1:	ldarx	%0,0,%1		# atomic64_inc_return\n\
357 	addic	%0,%0,1\n\
358 	stdcx.	%0,0,%1 \n\
359 	bne-	1b"
360 	ISYNC_ON_SMP
361 	: "=&r" (t)
362 	: "r" (&v->counter)
363 	: "cc", "xer", "memory");
364 
365 	return t;
366 }
367 
368 /*
369  * atomic64_inc_and_test - increment and test
370  * @v: pointer of type atomic64_t
371  *
372  * Atomically increments @v by 1
373  * and returns true if the result is zero, or false for all
374  * other cases.
375  */
376 #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
377 
378 static __inline__ void atomic64_dec(atomic64_t *v)
379 {
380 	long t;
381 
382 	__asm__ __volatile__(
383 "1:	ldarx	%0,0,%2		# atomic64_dec\n\
384 	addic	%0,%0,-1\n\
385 	stdcx.	%0,0,%2\n\
386 	bne-	1b"
387 	: "=&r" (t), "+m" (v->counter)
388 	: "r" (&v->counter)
389 	: "cc", "xer");
390 }
391 
392 static __inline__ long atomic64_dec_return(atomic64_t *v)
393 {
394 	long t;
395 
396 	__asm__ __volatile__(
397 	LWSYNC_ON_SMP
398 "1:	ldarx	%0,0,%1		# atomic64_dec_return\n\
399 	addic	%0,%0,-1\n\
400 	stdcx.	%0,0,%1\n\
401 	bne-	1b"
402 	ISYNC_ON_SMP
403 	: "=&r" (t)
404 	: "r" (&v->counter)
405 	: "cc", "xer", "memory");
406 
407 	return t;
408 }
409 
410 #define atomic64_sub_and_test(a, v)	(atomic64_sub_return((a), (v)) == 0)
411 #define atomic64_dec_and_test(v)	(atomic64_dec_return((v)) == 0)
412 
413 /*
414  * Atomically test *v and decrement if it is greater than 0.
415  * The function returns the old value of *v minus 1.
416  */
417 static __inline__ long atomic64_dec_if_positive(atomic64_t *v)
418 {
419 	long t;
420 
421 	__asm__ __volatile__(
422 	LWSYNC_ON_SMP
423 "1:	ldarx	%0,0,%1		# atomic64_dec_if_positive\n\
424 	addic.	%0,%0,-1\n\
425 	blt-	2f\n\
426 	stdcx.	%0,0,%1\n\
427 	bne-	1b"
428 	ISYNC_ON_SMP
429 	"\n\
430 2:"	: "=&r" (t)
431 	: "r" (&v->counter)
432 	: "cc", "xer", "memory");
433 
434 	return t;
435 }
436 
437 #define atomic64_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
438 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
439 
440 /**
441  * atomic64_add_unless - add unless the number is a given value
442  * @v: pointer of type atomic64_t
443  * @a: the amount to add to v...
444  * @u: ...unless v is equal to u.
445  *
446  * Atomically adds @a to @v, so long as it was not @u.
447  * Returns non-zero if @v was not @u, and zero otherwise.
448  */
449 static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
450 {
451 	long t;
452 
453 	__asm__ __volatile__ (
454 	LWSYNC_ON_SMP
455 "1:	ldarx	%0,0,%1		# atomic_add_unless\n\
456 	cmpd	0,%0,%3 \n\
457 	beq-	2f \n\
458 	add	%0,%2,%0 \n"
459 "	stdcx.	%0,0,%1 \n\
460 	bne-	1b \n"
461 	ISYNC_ON_SMP
462 "	subf	%0,%2,%0 \n\
463 2:"
464 	: "=&r" (t)
465 	: "r" (&v->counter), "r" (a), "r" (u)
466 	: "cc", "memory");
467 
468 	return t != u;
469 }
470 
471 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
472 
473 #else  /* __powerpc64__ */
474 #include <asm-generic/atomic64.h>
475 
476 #endif /* __powerpc64__ */
477 
478 #include <asm-generic/atomic-long.h>
479 #endif /* __KERNEL__ */
480 #endif /* _ASM_POWERPC_ATOMIC_H_ */
481