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8#ifndef __ASM_ARM_ATOMIC_H
9#define __ASM_ARM_ATOMIC_H
10
11#include <linux/compiler.h>
12#include <linux/prefetch.h>
13#include <linux/types.h>
14#include <linux/irqflags.h>
15#include <asm/barrier.h>
16#include <asm/cmpxchg.h>
17
18#ifdef __KERNEL__
19
20
21
22
23
24
25#define arch_atomic_read(v) READ_ONCE((v)->counter)
26#define arch_atomic_set(v,i) WRITE_ONCE(((v)->counter), (i))
27
28#if __LINUX_ARM_ARCH__ >= 6
29
30
31
32
33
34
35
36#define ATOMIC_OP(op, c_op, asm_op) \
37static inline void arch_atomic_##op(int i, atomic_t *v) \
38{ \
39 unsigned long tmp; \
40 int result; \
41 \
42 prefetchw(&v->counter); \
43 __asm__ __volatile__("@ atomic_" #op "\n" \
44"1: ldrex %0, [%3]\n" \
45" " #asm_op " %0, %0, %4\n" \
46" strex %1, %0, [%3]\n" \
47" teq %1, #0\n" \
48" bne 1b" \
49 : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter) \
50 : "r" (&v->counter), "Ir" (i) \
51 : "cc"); \
52} \
53
54#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
55static inline int arch_atomic_##op##_return_relaxed(int i, atomic_t *v) \
56{ \
57 unsigned long tmp; \
58 int result; \
59 \
60 prefetchw(&v->counter); \
61 \
62 __asm__ __volatile__("@ atomic_" #op "_return\n" \
63"1: ldrex %0, [%3]\n" \
64" " #asm_op " %0, %0, %4\n" \
65" strex %1, %0, [%3]\n" \
66" teq %1, #0\n" \
67" bne 1b" \
68 : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter) \
69 : "r" (&v->counter), "Ir" (i) \
70 : "cc"); \
71 \
72 return result; \
73}
74
75#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
76static inline int arch_atomic_fetch_##op##_relaxed(int i, atomic_t *v) \
77{ \
78 unsigned long tmp; \
79 int result, val; \
80 \
81 prefetchw(&v->counter); \
82 \
83 __asm__ __volatile__("@ atomic_fetch_" #op "\n" \
84"1: ldrex %0, [%4]\n" \
85" " #asm_op " %1, %0, %5\n" \
86" strex %2, %1, [%4]\n" \
87" teq %2, #0\n" \
88" bne 1b" \
89 : "=&r" (result), "=&r" (val), "=&r" (tmp), "+Qo" (v->counter) \
90 : "r" (&v->counter), "Ir" (i) \
91 : "cc"); \
92 \
93 return result; \
94}
95
96#define arch_atomic_add_return_relaxed arch_atomic_add_return_relaxed
97#define arch_atomic_sub_return_relaxed arch_atomic_sub_return_relaxed
98#define arch_atomic_fetch_add_relaxed arch_atomic_fetch_add_relaxed
99#define arch_atomic_fetch_sub_relaxed arch_atomic_fetch_sub_relaxed
100
101#define arch_atomic_fetch_and_relaxed arch_atomic_fetch_and_relaxed
102#define arch_atomic_fetch_andnot_relaxed arch_atomic_fetch_andnot_relaxed
103#define arch_atomic_fetch_or_relaxed arch_atomic_fetch_or_relaxed
104#define arch_atomic_fetch_xor_relaxed arch_atomic_fetch_xor_relaxed
105
106static inline int arch_atomic_cmpxchg_relaxed(atomic_t *ptr, int old, int new)
107{
108 int oldval;
109 unsigned long res;
110
111 prefetchw(&ptr->counter);
112
113 do {
114 __asm__ __volatile__("@ atomic_cmpxchg\n"
115 "ldrex %1, [%3]\n"
116 "mov %0, #0\n"
117 "teq %1, %4\n"
118 "strexeq %0, %5, [%3]\n"
119 : "=&r" (res), "=&r" (oldval), "+Qo" (ptr->counter)
120 : "r" (&ptr->counter), "Ir" (old), "r" (new)
121 : "cc");
122 } while (res);
123
124 return oldval;
125}
126#define arch_atomic_cmpxchg_relaxed arch_atomic_cmpxchg_relaxed
127
128static inline int arch_atomic_fetch_add_unless(atomic_t *v, int a, int u)
129{
130 int oldval, newval;
131 unsigned long tmp;
132
133 smp_mb();
134 prefetchw(&v->counter);
135
136 __asm__ __volatile__ ("@ atomic_add_unless\n"
137"1: ldrex %0, [%4]\n"
138" teq %0, %5\n"
139" beq 2f\n"
140" add %1, %0, %6\n"
141" strex %2, %1, [%4]\n"
142" teq %2, #0\n"
143" bne 1b\n"
144"2:"
145 : "=&r" (oldval), "=&r" (newval), "=&r" (tmp), "+Qo" (v->counter)
146 : "r" (&v->counter), "r" (u), "r" (a)
147 : "cc");
148
149 if (oldval != u)
150 smp_mb();
151
152 return oldval;
153}
154#define arch_atomic_fetch_add_unless arch_atomic_fetch_add_unless
155
156#else
157
158#ifdef CONFIG_SMP
159#error SMP not supported on pre-ARMv6 CPUs
160#endif
161
162#define ATOMIC_OP(op, c_op, asm_op) \
163static inline void arch_atomic_##op(int i, atomic_t *v) \
164{ \
165 unsigned long flags; \
166 \
167 raw_local_irq_save(flags); \
168 v->counter c_op i; \
169 raw_local_irq_restore(flags); \
170} \
171
172#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
173static inline int arch_atomic_##op##_return(int i, atomic_t *v) \
174{ \
175 unsigned long flags; \
176 int val; \
177 \
178 raw_local_irq_save(flags); \
179 v->counter c_op i; \
180 val = v->counter; \
181 raw_local_irq_restore(flags); \
182 \
183 return val; \
184}
185
186#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
187static inline int arch_atomic_fetch_##op(int i, atomic_t *v) \
188{ \
189 unsigned long flags; \
190 int val; \
191 \
192 raw_local_irq_save(flags); \
193 val = v->counter; \
194 v->counter c_op i; \
195 raw_local_irq_restore(flags); \
196 \
197 return val; \
198}
199
200static inline int arch_atomic_cmpxchg(atomic_t *v, int old, int new)
201{
202 int ret;
203 unsigned long flags;
204
205 raw_local_irq_save(flags);
206 ret = v->counter;
207 if (likely(ret == old))
208 v->counter = new;
209 raw_local_irq_restore(flags);
210
211 return ret;
212}
213
214#define arch_atomic_fetch_andnot arch_atomic_fetch_andnot
215
216#endif
217
218#define ATOMIC_OPS(op, c_op, asm_op) \
219 ATOMIC_OP(op, c_op, asm_op) \
220 ATOMIC_OP_RETURN(op, c_op, asm_op) \
221 ATOMIC_FETCH_OP(op, c_op, asm_op)
222
223ATOMIC_OPS(add, +=, add)
224ATOMIC_OPS(sub, -=, sub)
225
226#define arch_atomic_andnot arch_atomic_andnot
227
228#undef ATOMIC_OPS
229#define ATOMIC_OPS(op, c_op, asm_op) \
230 ATOMIC_OP(op, c_op, asm_op) \
231 ATOMIC_FETCH_OP(op, c_op, asm_op)
232
233ATOMIC_OPS(and, &=, and)
234ATOMIC_OPS(andnot, &= ~, bic)
235ATOMIC_OPS(or, |=, orr)
236ATOMIC_OPS(xor, ^=, eor)
237
238#undef ATOMIC_OPS
239#undef ATOMIC_FETCH_OP
240#undef ATOMIC_OP_RETURN
241#undef ATOMIC_OP
242
243#define arch_atomic_xchg(v, new) (arch_xchg(&((v)->counter), new))
244
245#ifndef CONFIG_GENERIC_ATOMIC64
246typedef struct {
247 s64 counter;
248} atomic64_t;
249
250#define ATOMIC64_INIT(i) { (i) }
251
252#ifdef CONFIG_ARM_LPAE
253static inline s64 arch_atomic64_read(const atomic64_t *v)
254{
255 s64 result;
256
257 __asm__ __volatile__("@ atomic64_read\n"
258" ldrd %0, %H0, [%1]"
259 : "=&r" (result)
260 : "r" (&v->counter), "Qo" (v->counter)
261 );
262
263 return result;
264}
265
266static inline void arch_atomic64_set(atomic64_t *v, s64 i)
267{
268 __asm__ __volatile__("@ atomic64_set\n"
269" strd %2, %H2, [%1]"
270 : "=Qo" (v->counter)
271 : "r" (&v->counter), "r" (i)
272 );
273}
274#else
275static inline s64 arch_atomic64_read(const atomic64_t *v)
276{
277 s64 result;
278
279 __asm__ __volatile__("@ atomic64_read\n"
280" ldrexd %0, %H0, [%1]"
281 : "=&r" (result)
282 : "r" (&v->counter), "Qo" (v->counter)
283 );
284
285 return result;
286}
287
288static inline void arch_atomic64_set(atomic64_t *v, s64 i)
289{
290 s64 tmp;
291
292 prefetchw(&v->counter);
293 __asm__ __volatile__("@ atomic64_set\n"
294"1: ldrexd %0, %H0, [%2]\n"
295" strexd %0, %3, %H3, [%2]\n"
296" teq %0, #0\n"
297" bne 1b"
298 : "=&r" (tmp), "=Qo" (v->counter)
299 : "r" (&v->counter), "r" (i)
300 : "cc");
301}
302#endif
303
304#define ATOMIC64_OP(op, op1, op2) \
305static inline void arch_atomic64_##op(s64 i, atomic64_t *v) \
306{ \
307 s64 result; \
308 unsigned long tmp; \
309 \
310 prefetchw(&v->counter); \
311 __asm__ __volatile__("@ atomic64_" #op "\n" \
312"1: ldrexd %0, %H0, [%3]\n" \
313" " #op1 " %Q0, %Q0, %Q4\n" \
314" " #op2 " %R0, %R0, %R4\n" \
315" strexd %1, %0, %H0, [%3]\n" \
316" teq %1, #0\n" \
317" bne 1b" \
318 : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter) \
319 : "r" (&v->counter), "r" (i) \
320 : "cc"); \
321} \
322
323#define ATOMIC64_OP_RETURN(op, op1, op2) \
324static inline s64 \
325arch_atomic64_##op##_return_relaxed(s64 i, atomic64_t *v) \
326{ \
327 s64 result; \
328 unsigned long tmp; \
329 \
330 prefetchw(&v->counter); \
331 \
332 __asm__ __volatile__("@ atomic64_" #op "_return\n" \
333"1: ldrexd %0, %H0, [%3]\n" \
334" " #op1 " %Q0, %Q0, %Q4\n" \
335" " #op2 " %R0, %R0, %R4\n" \
336" strexd %1, %0, %H0, [%3]\n" \
337" teq %1, #0\n" \
338" bne 1b" \
339 : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter) \
340 : "r" (&v->counter), "r" (i) \
341 : "cc"); \
342 \
343 return result; \
344}
345
346#define ATOMIC64_FETCH_OP(op, op1, op2) \
347static inline s64 \
348arch_atomic64_fetch_##op##_relaxed(s64 i, atomic64_t *v) \
349{ \
350 s64 result, val; \
351 unsigned long tmp; \
352 \
353 prefetchw(&v->counter); \
354 \
355 __asm__ __volatile__("@ atomic64_fetch_" #op "\n" \
356"1: ldrexd %0, %H0, [%4]\n" \
357" " #op1 " %Q1, %Q0, %Q5\n" \
358" " #op2 " %R1, %R0, %R5\n" \
359" strexd %2, %1, %H1, [%4]\n" \
360" teq %2, #0\n" \
361" bne 1b" \
362 : "=&r" (result), "=&r" (val), "=&r" (tmp), "+Qo" (v->counter) \
363 : "r" (&v->counter), "r" (i) \
364 : "cc"); \
365 \
366 return result; \
367}
368
369#define ATOMIC64_OPS(op, op1, op2) \
370 ATOMIC64_OP(op, op1, op2) \
371 ATOMIC64_OP_RETURN(op, op1, op2) \
372 ATOMIC64_FETCH_OP(op, op1, op2)
373
374ATOMIC64_OPS(add, adds, adc)
375ATOMIC64_OPS(sub, subs, sbc)
376
377#define arch_atomic64_add_return_relaxed arch_atomic64_add_return_relaxed
378#define arch_atomic64_sub_return_relaxed arch_atomic64_sub_return_relaxed
379#define arch_atomic64_fetch_add_relaxed arch_atomic64_fetch_add_relaxed
380#define arch_atomic64_fetch_sub_relaxed arch_atomic64_fetch_sub_relaxed
381
382#undef ATOMIC64_OPS
383#define ATOMIC64_OPS(op, op1, op2) \
384 ATOMIC64_OP(op, op1, op2) \
385 ATOMIC64_FETCH_OP(op, op1, op2)
386
387#define arch_atomic64_andnot arch_atomic64_andnot
388
389ATOMIC64_OPS(and, and, and)
390ATOMIC64_OPS(andnot, bic, bic)
391ATOMIC64_OPS(or, orr, orr)
392ATOMIC64_OPS(xor, eor, eor)
393
394#define arch_atomic64_fetch_and_relaxed arch_atomic64_fetch_and_relaxed
395#define arch_atomic64_fetch_andnot_relaxed arch_atomic64_fetch_andnot_relaxed
396#define arch_atomic64_fetch_or_relaxed arch_atomic64_fetch_or_relaxed
397#define arch_atomic64_fetch_xor_relaxed arch_atomic64_fetch_xor_relaxed
398
399#undef ATOMIC64_OPS
400#undef ATOMIC64_FETCH_OP
401#undef ATOMIC64_OP_RETURN
402#undef ATOMIC64_OP
403
404static inline s64 arch_atomic64_cmpxchg_relaxed(atomic64_t *ptr, s64 old, s64 new)
405{
406 s64 oldval;
407 unsigned long res;
408
409 prefetchw(&ptr->counter);
410
411 do {
412 __asm__ __volatile__("@ atomic64_cmpxchg\n"
413 "ldrexd %1, %H1, [%3]\n"
414 "mov %0, #0\n"
415 "teq %1, %4\n"
416 "teqeq %H1, %H4\n"
417 "strexdeq %0, %5, %H5, [%3]"
418 : "=&r" (res), "=&r" (oldval), "+Qo" (ptr->counter)
419 : "r" (&ptr->counter), "r" (old), "r" (new)
420 : "cc");
421 } while (res);
422
423 return oldval;
424}
425#define arch_atomic64_cmpxchg_relaxed arch_atomic64_cmpxchg_relaxed
426
427static inline s64 arch_atomic64_xchg_relaxed(atomic64_t *ptr, s64 new)
428{
429 s64 result;
430 unsigned long tmp;
431
432 prefetchw(&ptr->counter);
433
434 __asm__ __volatile__("@ atomic64_xchg\n"
435"1: ldrexd %0, %H0, [%3]\n"
436" strexd %1, %4, %H4, [%3]\n"
437" teq %1, #0\n"
438" bne 1b"
439 : "=&r" (result), "=&r" (tmp), "+Qo" (ptr->counter)
440 : "r" (&ptr->counter), "r" (new)
441 : "cc");
442
443 return result;
444}
445#define arch_atomic64_xchg_relaxed arch_atomic64_xchg_relaxed
446
447static inline s64 arch_atomic64_dec_if_positive(atomic64_t *v)
448{
449 s64 result;
450 unsigned long tmp;
451
452 smp_mb();
453 prefetchw(&v->counter);
454
455 __asm__ __volatile__("@ atomic64_dec_if_positive\n"
456"1: ldrexd %0, %H0, [%3]\n"
457" subs %Q0, %Q0, #1\n"
458" sbc %R0, %R0, #0\n"
459" teq %R0, #0\n"
460" bmi 2f\n"
461" strexd %1, %0, %H0, [%3]\n"
462" teq %1, #0\n"
463" bne 1b\n"
464"2:"
465 : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
466 : "r" (&v->counter)
467 : "cc");
468
469 smp_mb();
470
471 return result;
472}
473#define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive
474
475static inline s64 arch_atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
476{
477 s64 oldval, newval;
478 unsigned long tmp;
479
480 smp_mb();
481 prefetchw(&v->counter);
482
483 __asm__ __volatile__("@ atomic64_add_unless\n"
484"1: ldrexd %0, %H0, [%4]\n"
485" teq %0, %5\n"
486" teqeq %H0, %H5\n"
487" beq 2f\n"
488" adds %Q1, %Q0, %Q6\n"
489" adc %R1, %R0, %R6\n"
490" strexd %2, %1, %H1, [%4]\n"
491" teq %2, #0\n"
492" bne 1b\n"
493"2:"
494 : "=&r" (oldval), "=&r" (newval), "=&r" (tmp), "+Qo" (v->counter)
495 : "r" (&v->counter), "r" (u), "r" (a)
496 : "cc");
497
498 if (oldval != u)
499 smp_mb();
500
501 return oldval;
502}
503#define arch_atomic64_fetch_add_unless arch_atomic64_fetch_add_unless
504
505#endif
506#endif
507#endif
508
