Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_POWERPC_ATOMIC_H_
3#define _ASM_POWERPC_ATOMIC_H_
4
5/*
6 * PowerPC atomic operations
7 */
8
9#ifdef __KERNEL__
10#include <linux/types.h>
11#include <asm/cmpxchg.h>
12#include <asm/barrier.h>
13#include <asm/asm-405.h>
14
15#define ATOMIC_INIT(i) { (i) }
16
17/*
18 * Since *_return_relaxed and {cmp}xchg_relaxed are implemented with
19 * a "bne-" instruction at the end, so an isync is enough as a acquire barrier
20 * on the platform without lwsync.
21 */
22#define __atomic_acquire_fence() \
23 __asm__ __volatile__(PPC_ACQUIRE_BARRIER "" : : : "memory")
24
25#define __atomic_release_fence() \
26 __asm__ __volatile__(PPC_RELEASE_BARRIER "" : : : "memory")
27
28static __inline__ int atomic_read(const atomic_t *v)
29{
30 int t;
31
32 __asm__ __volatile__("lwz%U1%X1 %0,%1" : "=r"(t) : "m"(v->counter));
33
34 return t;
35}
36
37static __inline__ void atomic_set(atomic_t *v, int i)
38{
39 __asm__ __volatile__("stw%U0%X0 %1,%0" : "=m"(v->counter) : "r"(i));
40}
41
42#define ATOMIC_OP(op, asm_op) \
43static __inline__ void atomic_##op(int a, atomic_t *v) \
44{ \
45 int t; \
46 \
47 __asm__ __volatile__( \
48"1: lwarx %0,0,%3 # atomic_" #op "\n" \
49 #asm_op " %0,%2,%0\n" \
50 PPC405_ERR77(0,%3) \
51" stwcx. %0,0,%3 \n" \
52" bne- 1b\n" \
53 : "=&r" (t), "+m" (v->counter) \
54 : "r" (a), "r" (&v->counter) \
55 : "cc"); \
56} \
57
58#define ATOMIC_OP_RETURN_RELAXED(op, asm_op) \
59static inline int atomic_##op##_return_relaxed(int a, atomic_t *v) \
60{ \
61 int t; \
62 \
63 __asm__ __volatile__( \
64"1: lwarx %0,0,%3 # atomic_" #op "_return_relaxed\n" \
65 #asm_op " %0,%2,%0\n" \
66 PPC405_ERR77(0, %3) \
67" stwcx. %0,0,%3\n" \
68" bne- 1b\n" \
69 : "=&r" (t), "+m" (v->counter) \
70 : "r" (a), "r" (&v->counter) \
71 : "cc"); \
72 \
73 return t; \
74}
75
76#define ATOMIC_FETCH_OP_RELAXED(op, asm_op) \
77static inline int atomic_fetch_##op##_relaxed(int a, atomic_t *v) \
78{ \
79 int res, t; \
80 \
81 __asm__ __volatile__( \
82"1: lwarx %0,0,%4 # atomic_fetch_" #op "_relaxed\n" \
83 #asm_op " %1,%3,%0\n" \
84 PPC405_ERR77(0, %4) \
85" stwcx. %1,0,%4\n" \
86" bne- 1b\n" \
87 : "=&r" (res), "=&r" (t), "+m" (v->counter) \
88 : "r" (a), "r" (&v->counter) \
89 : "cc"); \
90 \
91 return res; \
92}
93
94#define ATOMIC_OPS(op, asm_op) \
95 ATOMIC_OP(op, asm_op) \
96 ATOMIC_OP_RETURN_RELAXED(op, asm_op) \
97 ATOMIC_FETCH_OP_RELAXED(op, asm_op)
98
99ATOMIC_OPS(add, add)
100ATOMIC_OPS(sub, subf)
101
102#define atomic_add_return_relaxed atomic_add_return_relaxed
103#define atomic_sub_return_relaxed atomic_sub_return_relaxed
104
105#define atomic_fetch_add_relaxed atomic_fetch_add_relaxed
106#define atomic_fetch_sub_relaxed atomic_fetch_sub_relaxed
107
108#undef ATOMIC_OPS
109#define ATOMIC_OPS(op, asm_op) \
110 ATOMIC_OP(op, asm_op) \
111 ATOMIC_FETCH_OP_RELAXED(op, asm_op)
112
113ATOMIC_OPS(and, and)
114ATOMIC_OPS(or, or)
115ATOMIC_OPS(xor, xor)
116
117#define atomic_fetch_and_relaxed atomic_fetch_and_relaxed
118#define atomic_fetch_or_relaxed atomic_fetch_or_relaxed
119#define atomic_fetch_xor_relaxed atomic_fetch_xor_relaxed
120
121#undef ATOMIC_OPS
122#undef ATOMIC_FETCH_OP_RELAXED
123#undef ATOMIC_OP_RETURN_RELAXED
124#undef ATOMIC_OP
125
126static __inline__ void atomic_inc(atomic_t *v)
127{
128 int t;
129
130 __asm__ __volatile__(
131"1: lwarx %0,0,%2 # atomic_inc\n\
132 addic %0,%0,1\n"
133 PPC405_ERR77(0,%2)
134" stwcx. %0,0,%2 \n\
135 bne- 1b"
136 : "=&r" (t), "+m" (v->counter)
137 : "r" (&v->counter)
138 : "cc", "xer");
139}
140#define atomic_inc atomic_inc
141
142static __inline__ int atomic_inc_return_relaxed(atomic_t *v)
143{
144 int t;
145
146 __asm__ __volatile__(
147"1: lwarx %0,0,%2 # atomic_inc_return_relaxed\n"
148" addic %0,%0,1\n"
149 PPC405_ERR77(0, %2)
150" stwcx. %0,0,%2\n"
151" bne- 1b"
152 : "=&r" (t), "+m" (v->counter)
153 : "r" (&v->counter)
154 : "cc", "xer");
155
156 return t;
157}
158
159static __inline__ void atomic_dec(atomic_t *v)
160{
161 int t;
162
163 __asm__ __volatile__(
164"1: lwarx %0,0,%2 # atomic_dec\n\
165 addic %0,%0,-1\n"
166 PPC405_ERR77(0,%2)\
167" stwcx. %0,0,%2\n\
168 bne- 1b"
169 : "=&r" (t), "+m" (v->counter)
170 : "r" (&v->counter)
171 : "cc", "xer");
172}
173#define atomic_dec atomic_dec
174
175static __inline__ int atomic_dec_return_relaxed(atomic_t *v)
176{
177 int t;
178
179 __asm__ __volatile__(
180"1: lwarx %0,0,%2 # atomic_dec_return_relaxed\n"
181" addic %0,%0,-1\n"
182 PPC405_ERR77(0, %2)
183" stwcx. %0,0,%2\n"
184" bne- 1b"
185 : "=&r" (t), "+m" (v->counter)
186 : "r" (&v->counter)
187 : "cc", "xer");
188
189 return t;
190}
191
192#define atomic_inc_return_relaxed atomic_inc_return_relaxed
193#define atomic_dec_return_relaxed atomic_dec_return_relaxed
194
195#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
196#define atomic_cmpxchg_relaxed(v, o, n) \
197 cmpxchg_relaxed(&((v)->counter), (o), (n))
198#define atomic_cmpxchg_acquire(v, o, n) \
199 cmpxchg_acquire(&((v)->counter), (o), (n))
200
201#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
202#define atomic_xchg_relaxed(v, new) xchg_relaxed(&((v)->counter), (new))
203
204/**
205 * atomic_fetch_add_unless - add unless the number is a given value
206 * @v: pointer of type atomic_t
207 * @a: the amount to add to v...
208 * @u: ...unless v is equal to u.
209 *
210 * Atomically adds @a to @v, so long as it was not @u.
211 * Returns the old value of @v.
212 */
213static __inline__ int atomic_fetch_add_unless(atomic_t *v, int a, int u)
214{
215 int t;
216
217 __asm__ __volatile__ (
218 PPC_ATOMIC_ENTRY_BARRIER
219"1: lwarx %0,0,%1 # atomic_fetch_add_unless\n\
220 cmpw 0,%0,%3 \n\
221 beq 2f \n\
222 add %0,%2,%0 \n"
223 PPC405_ERR77(0,%2)
224" stwcx. %0,0,%1 \n\
225 bne- 1b \n"
226 PPC_ATOMIC_EXIT_BARRIER
227" subf %0,%2,%0 \n\
2282:"
229 : "=&r" (t)
230 : "r" (&v->counter), "r" (a), "r" (u)
231 : "cc", "memory");
232
233 return t;
234}
235#define atomic_fetch_add_unless atomic_fetch_add_unless
236
237/**
238 * atomic_inc_not_zero - increment unless the number is zero
239 * @v: pointer of type atomic_t
240 *
241 * Atomically increments @v by 1, so long as @v is non-zero.
242 * Returns non-zero if @v was non-zero, and zero otherwise.
243 */
244static __inline__ int atomic_inc_not_zero(atomic_t *v)
245{
246 int t1, t2;
247
248 __asm__ __volatile__ (
249 PPC_ATOMIC_ENTRY_BARRIER
250"1: lwarx %0,0,%2 # atomic_inc_not_zero\n\
251 cmpwi 0,%0,0\n\
252 beq- 2f\n\
253 addic %1,%0,1\n"
254 PPC405_ERR77(0,%2)
255" stwcx. %1,0,%2\n\
256 bne- 1b\n"
257 PPC_ATOMIC_EXIT_BARRIER
258 "\n\
2592:"
260 : "=&r" (t1), "=&r" (t2)
261 : "r" (&v->counter)
262 : "cc", "xer", "memory");
263
264 return t1;
265}
266#define atomic_inc_not_zero(v) atomic_inc_not_zero((v))
267
268/*
269 * Atomically test *v and decrement if it is greater than 0.
270 * The function returns the old value of *v minus 1, even if
271 * the atomic variable, v, was not decremented.
272 */
273static __inline__ int atomic_dec_if_positive(atomic_t *v)
274{
275 int t;
276
277 __asm__ __volatile__(
278 PPC_ATOMIC_ENTRY_BARRIER
279"1: lwarx %0,0,%1 # atomic_dec_if_positive\n\
280 cmpwi %0,1\n\
281 addi %0,%0,-1\n\
282 blt- 2f\n"
283 PPC405_ERR77(0,%1)
284" stwcx. %0,0,%1\n\
285 bne- 1b"
286 PPC_ATOMIC_EXIT_BARRIER
287 "\n\
2882:" : "=&b" (t)
289 : "r" (&v->counter)
290 : "cc", "memory");
291
292 return t;
293}
294#define atomic_dec_if_positive atomic_dec_if_positive
295
296#ifdef __powerpc64__
297
298#define ATOMIC64_INIT(i) { (i) }
299
300static __inline__ s64 atomic64_read(const atomic64_t *v)
301{
302 s64 t;
303
304 __asm__ __volatile__("ld%U1%X1 %0,%1" : "=r"(t) : "m"(v->counter));
305
306 return t;
307}
308
309static __inline__ void atomic64_set(atomic64_t *v, s64 i)
310{
311 __asm__ __volatile__("std%U0%X0 %1,%0" : "=m"(v->counter) : "r"(i));
312}
313
314#define ATOMIC64_OP(op, asm_op) \
315static __inline__ void atomic64_##op(s64 a, atomic64_t *v) \
316{ \
317 s64 t; \
318 \
319 __asm__ __volatile__( \
320"1: ldarx %0,0,%3 # atomic64_" #op "\n" \
321 #asm_op " %0,%2,%0\n" \
322" stdcx. %0,0,%3 \n" \
323" bne- 1b\n" \
324 : "=&r" (t), "+m" (v->counter) \
325 : "r" (a), "r" (&v->counter) \
326 : "cc"); \
327}
328
329#define ATOMIC64_OP_RETURN_RELAXED(op, asm_op) \
330static inline s64 \
331atomic64_##op##_return_relaxed(s64 a, atomic64_t *v) \
332{ \
333 s64 t; \
334 \
335 __asm__ __volatile__( \
336"1: ldarx %0,0,%3 # atomic64_" #op "_return_relaxed\n" \
337 #asm_op " %0,%2,%0\n" \
338" stdcx. %0,0,%3\n" \
339" bne- 1b\n" \
340 : "=&r" (t), "+m" (v->counter) \
341 : "r" (a), "r" (&v->counter) \
342 : "cc"); \
343 \
344 return t; \
345}
346
347#define ATOMIC64_FETCH_OP_RELAXED(op, asm_op) \
348static inline s64 \
349atomic64_fetch_##op##_relaxed(s64 a, atomic64_t *v) \
350{ \
351 s64 res, t; \
352 \
353 __asm__ __volatile__( \
354"1: ldarx %0,0,%4 # atomic64_fetch_" #op "_relaxed\n" \
355 #asm_op " %1,%3,%0\n" \
356" stdcx. %1,0,%4\n" \
357" bne- 1b\n" \
358 : "=&r" (res), "=&r" (t), "+m" (v->counter) \
359 : "r" (a), "r" (&v->counter) \
360 : "cc"); \
361 \
362 return res; \
363}
364
365#define ATOMIC64_OPS(op, asm_op) \
366 ATOMIC64_OP(op, asm_op) \
367 ATOMIC64_OP_RETURN_RELAXED(op, asm_op) \
368 ATOMIC64_FETCH_OP_RELAXED(op, asm_op)
369
370ATOMIC64_OPS(add, add)
371ATOMIC64_OPS(sub, subf)
372
373#define atomic64_add_return_relaxed atomic64_add_return_relaxed
374#define atomic64_sub_return_relaxed atomic64_sub_return_relaxed
375
376#define atomic64_fetch_add_relaxed atomic64_fetch_add_relaxed
377#define atomic64_fetch_sub_relaxed atomic64_fetch_sub_relaxed
378
379#undef ATOMIC64_OPS
380#define ATOMIC64_OPS(op, asm_op) \
381 ATOMIC64_OP(op, asm_op) \
382 ATOMIC64_FETCH_OP_RELAXED(op, asm_op)
383
384ATOMIC64_OPS(and, and)
385ATOMIC64_OPS(or, or)
386ATOMIC64_OPS(xor, xor)
387
388#define atomic64_fetch_and_relaxed atomic64_fetch_and_relaxed
389#define atomic64_fetch_or_relaxed atomic64_fetch_or_relaxed
390#define atomic64_fetch_xor_relaxed atomic64_fetch_xor_relaxed
391
392#undef ATOPIC64_OPS
393#undef ATOMIC64_FETCH_OP_RELAXED
394#undef ATOMIC64_OP_RETURN_RELAXED
395#undef ATOMIC64_OP
396
397static __inline__ void atomic64_inc(atomic64_t *v)
398{
399 s64 t;
400
401 __asm__ __volatile__(
402"1: ldarx %0,0,%2 # atomic64_inc\n\
403 addic %0,%0,1\n\
404 stdcx. %0,0,%2 \n\
405 bne- 1b"
406 : "=&r" (t), "+m" (v->counter)
407 : "r" (&v->counter)
408 : "cc", "xer");
409}
410#define atomic64_inc atomic64_inc
411
412static __inline__ s64 atomic64_inc_return_relaxed(atomic64_t *v)
413{
414 s64 t;
415
416 __asm__ __volatile__(
417"1: ldarx %0,0,%2 # atomic64_inc_return_relaxed\n"
418" addic %0,%0,1\n"
419" stdcx. %0,0,%2\n"
420" bne- 1b"
421 : "=&r" (t), "+m" (v->counter)
422 : "r" (&v->counter)
423 : "cc", "xer");
424
425 return t;
426}
427
428static __inline__ void atomic64_dec(atomic64_t *v)
429{
430 s64 t;
431
432 __asm__ __volatile__(
433"1: ldarx %0,0,%2 # atomic64_dec\n\
434 addic %0,%0,-1\n\
435 stdcx. %0,0,%2\n\
436 bne- 1b"
437 : "=&r" (t), "+m" (v->counter)
438 : "r" (&v->counter)
439 : "cc", "xer");
440}
441#define atomic64_dec atomic64_dec
442
443static __inline__ s64 atomic64_dec_return_relaxed(atomic64_t *v)
444{
445 s64 t;
446
447 __asm__ __volatile__(
448"1: ldarx %0,0,%2 # atomic64_dec_return_relaxed\n"
449" addic %0,%0,-1\n"
450" stdcx. %0,0,%2\n"
451" bne- 1b"
452 : "=&r" (t), "+m" (v->counter)
453 : "r" (&v->counter)
454 : "cc", "xer");
455
456 return t;
457}
458
459#define atomic64_inc_return_relaxed atomic64_inc_return_relaxed
460#define atomic64_dec_return_relaxed atomic64_dec_return_relaxed
461
462/*
463 * Atomically test *v and decrement if it is greater than 0.
464 * The function returns the old value of *v minus 1.
465 */
466static __inline__ s64 atomic64_dec_if_positive(atomic64_t *v)
467{
468 s64 t;
469
470 __asm__ __volatile__(
471 PPC_ATOMIC_ENTRY_BARRIER
472"1: ldarx %0,0,%1 # atomic64_dec_if_positive\n\
473 addic. %0,%0,-1\n\
474 blt- 2f\n\
475 stdcx. %0,0,%1\n\
476 bne- 1b"
477 PPC_ATOMIC_EXIT_BARRIER
478 "\n\
4792:" : "=&r" (t)
480 : "r" (&v->counter)
481 : "cc", "xer", "memory");
482
483 return t;
484}
485#define atomic64_dec_if_positive atomic64_dec_if_positive
486
487#define atomic64_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
488#define atomic64_cmpxchg_relaxed(v, o, n) \
489 cmpxchg_relaxed(&((v)->counter), (o), (n))
490#define atomic64_cmpxchg_acquire(v, o, n) \
491 cmpxchg_acquire(&((v)->counter), (o), (n))
492
493#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
494#define atomic64_xchg_relaxed(v, new) xchg_relaxed(&((v)->counter), (new))
495
496/**
497 * atomic64_fetch_add_unless - add unless the number is a given value
498 * @v: pointer of type atomic64_t
499 * @a: the amount to add to v...
500 * @u: ...unless v is equal to u.
501 *
502 * Atomically adds @a to @v, so long as it was not @u.
503 * Returns the old value of @v.
504 */
505static __inline__ s64 atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
506{
507 s64 t;
508
509 __asm__ __volatile__ (
510 PPC_ATOMIC_ENTRY_BARRIER
511"1: ldarx %0,0,%1 # atomic64_fetch_add_unless\n\
512 cmpd 0,%0,%3 \n\
513 beq 2f \n\
514 add %0,%2,%0 \n"
515" stdcx. %0,0,%1 \n\
516 bne- 1b \n"
517 PPC_ATOMIC_EXIT_BARRIER
518" subf %0,%2,%0 \n\
5192:"
520 : "=&r" (t)
521 : "r" (&v->counter), "r" (a), "r" (u)
522 : "cc", "memory");
523
524 return t;
525}
526#define atomic64_fetch_add_unless atomic64_fetch_add_unless
527
528/**
529 * atomic_inc64_not_zero - increment unless the number is zero
530 * @v: pointer of type atomic64_t
531 *
532 * Atomically increments @v by 1, so long as @v is non-zero.
533 * Returns non-zero if @v was non-zero, and zero otherwise.
534 */
535static __inline__ int atomic64_inc_not_zero(atomic64_t *v)
536{
537 s64 t1, t2;
538
539 __asm__ __volatile__ (
540 PPC_ATOMIC_ENTRY_BARRIER
541"1: ldarx %0,0,%2 # atomic64_inc_not_zero\n\
542 cmpdi 0,%0,0\n\
543 beq- 2f\n\
544 addic %1,%0,1\n\
545 stdcx. %1,0,%2\n\
546 bne- 1b\n"
547 PPC_ATOMIC_EXIT_BARRIER
548 "\n\
5492:"
550 : "=&r" (t1), "=&r" (t2)
551 : "r" (&v->counter)
552 : "cc", "xer", "memory");
553
554 return t1 != 0;
555}
556#define atomic64_inc_not_zero(v) atomic64_inc_not_zero((v))
557
558#endif /* __powerpc64__ */
559
560#endif /* __KERNEL__ */
561#endif /* _ASM_POWERPC_ATOMIC_H_ */