1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Atomic operations.
4 *
5 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
6 */
7 #ifndef _ASM_ATOMIC_H
8 #define _ASM_ATOMIC_H
9
10 #include <linux/types.h>
11 #include <asm/barrier.h>
12 #include <asm/cmpxchg.h>
13
14 #if __SIZEOF_LONG__ == 4
15 #define __LL "ll.w "
16 #define __SC "sc.w "
17 #define __AMADD "amadd.w "
18 #define __AMAND_DB "amand_db.w "
19 #define __AMOR_DB "amor_db.w "
20 #define __AMXOR_DB "amxor_db.w "
21 #elif __SIZEOF_LONG__ == 8
22 #define __LL "ll.d "
23 #define __SC "sc.d "
24 #define __AMADD "amadd.d "
25 #define __AMAND_DB "amand_db.d "
26 #define __AMOR_DB "amor_db.d "
27 #define __AMXOR_DB "amxor_db.d "
28 #endif
29
30 #define ATOMIC_INIT(i) { (i) }
31
32 #define arch_atomic_read(v) READ_ONCE((v)->counter)
33 #define arch_atomic_set(v, i) WRITE_ONCE((v)->counter, (i))
34
35 #define ATOMIC_OP(op, I, asm_op) \
36 static inline void arch_atomic_##op(int i, atomic_t *v) \
37 { \
38 __asm__ __volatile__( \
39 "am"#asm_op".w" " $zero, %1, %0 \n" \
40 : "+ZB" (v->counter) \
41 : "r" (I) \
42 : "memory"); \
43 }
44
45 #define ATOMIC_OP_RETURN(op, I, asm_op, c_op, mb, suffix) \
46 static inline int arch_atomic_##op##_return##suffix(int i, atomic_t *v) \
47 { \
48 int result; \
49 \
50 __asm__ __volatile__( \
51 "am"#asm_op#mb".w" " %1, %2, %0 \n" \
52 : "+ZB" (v->counter), "=&r" (result) \
53 : "r" (I) \
54 : "memory"); \
55 \
56 return result c_op I; \
57 }
58
59 #define ATOMIC_FETCH_OP(op, I, asm_op, mb, suffix) \
60 static inline int arch_atomic_fetch_##op##suffix(int i, atomic_t *v) \
61 { \
62 int result; \
63 \
64 __asm__ __volatile__( \
65 "am"#asm_op#mb".w" " %1, %2, %0 \n" \
66 : "+ZB" (v->counter), "=&r" (result) \
67 : "r" (I) \
68 : "memory"); \
69 \
70 return result; \
71 }
72
73 #define ATOMIC_OPS(op, I, asm_op, c_op) \
74 ATOMIC_OP(op, I, asm_op) \
75 ATOMIC_OP_RETURN(op, I, asm_op, c_op, _db, ) \
76 ATOMIC_OP_RETURN(op, I, asm_op, c_op, , _relaxed) \
77 ATOMIC_FETCH_OP(op, I, asm_op, _db, ) \
78 ATOMIC_FETCH_OP(op, I, asm_op, , _relaxed)
79
80 ATOMIC_OPS(add, i, add, +)
81 ATOMIC_OPS(sub, -i, add, +)
82
83 #define arch_atomic_add_return arch_atomic_add_return
84 #define arch_atomic_add_return_acquire arch_atomic_add_return
85 #define arch_atomic_add_return_release arch_atomic_add_return
86 #define arch_atomic_add_return_relaxed arch_atomic_add_return_relaxed
87 #define arch_atomic_sub_return arch_atomic_sub_return
88 #define arch_atomic_sub_return_acquire arch_atomic_sub_return
89 #define arch_atomic_sub_return_release arch_atomic_sub_return
90 #define arch_atomic_sub_return_relaxed arch_atomic_sub_return_relaxed
91 #define arch_atomic_fetch_add arch_atomic_fetch_add
92 #define arch_atomic_fetch_add_acquire arch_atomic_fetch_add
93 #define arch_atomic_fetch_add_release arch_atomic_fetch_add
94 #define arch_atomic_fetch_add_relaxed arch_atomic_fetch_add_relaxed
95 #define arch_atomic_fetch_sub arch_atomic_fetch_sub
96 #define arch_atomic_fetch_sub_acquire arch_atomic_fetch_sub
97 #define arch_atomic_fetch_sub_release arch_atomic_fetch_sub
98 #define arch_atomic_fetch_sub_relaxed arch_atomic_fetch_sub_relaxed
99
100 #undef ATOMIC_OPS
101
102 #define ATOMIC_OPS(op, I, asm_op) \
103 ATOMIC_OP(op, I, asm_op) \
104 ATOMIC_FETCH_OP(op, I, asm_op, _db, ) \
105 ATOMIC_FETCH_OP(op, I, asm_op, , _relaxed)
106
107 ATOMIC_OPS(and, i, and)
108 ATOMIC_OPS(or, i, or)
109 ATOMIC_OPS(xor, i, xor)
110
111 #define arch_atomic_fetch_and arch_atomic_fetch_and
112 #define arch_atomic_fetch_and_acquire arch_atomic_fetch_and
113 #define arch_atomic_fetch_and_release arch_atomic_fetch_and
114 #define arch_atomic_fetch_and_relaxed arch_atomic_fetch_and_relaxed
115 #define arch_atomic_fetch_or arch_atomic_fetch_or
116 #define arch_atomic_fetch_or_acquire arch_atomic_fetch_or
117 #define arch_atomic_fetch_or_release arch_atomic_fetch_or
118 #define arch_atomic_fetch_or_relaxed arch_atomic_fetch_or_relaxed
119 #define arch_atomic_fetch_xor arch_atomic_fetch_xor
120 #define arch_atomic_fetch_xor_acquire arch_atomic_fetch_xor
121 #define arch_atomic_fetch_xor_release arch_atomic_fetch_xor
122 #define arch_atomic_fetch_xor_relaxed arch_atomic_fetch_xor_relaxed
123
124 #undef ATOMIC_OPS
125 #undef ATOMIC_FETCH_OP
126 #undef ATOMIC_OP_RETURN
127 #undef ATOMIC_OP
128
129 static inline int arch_atomic_fetch_add_unless(atomic_t *v, int a, int u)
130 {
131 int prev, rc;
132
133 __asm__ __volatile__ (
134 "0: ll.w %[p], %[c]\n"
135 " beq %[p], %[u], 1f\n"
136 " add.w %[rc], %[p], %[a]\n"
137 " sc.w %[rc], %[c]\n"
138 " beqz %[rc], 0b\n"
139 " b 2f\n"
140 "1:\n"
141 __WEAK_LLSC_MB
142 "2:\n"
143 : [p]"=&r" (prev), [rc]"=&r" (rc),
144 [c]"=ZB" (v->counter)
145 : [a]"r" (a), [u]"r" (u)
146 : "memory");
147
148 return prev;
149 }
150 #define arch_atomic_fetch_add_unless arch_atomic_fetch_add_unless
151
152 static inline int arch_atomic_sub_if_positive(int i, atomic_t *v)
153 {
154 int result;
155 int temp;
156
157 if (__builtin_constant_p(i)) {
158 __asm__ __volatile__(
159 "1: ll.w %1, %2 # atomic_sub_if_positive\n"
160 " addi.w %0, %1, %3 \n"
161 " move %1, %0 \n"
162 " bltz %0, 2f \n"
163 " sc.w %1, %2 \n"
164 " beqz %1, 1b \n"
165 "2: \n"
166 __WEAK_LLSC_MB
167 : "=&r" (result), "=&r" (temp), "+ZC" (v->counter)
168 : "I" (-i));
169 } else {
170 __asm__ __volatile__(
171 "1: ll.w %1, %2 # atomic_sub_if_positive\n"
172 " sub.w %0, %1, %3 \n"
173 " move %1, %0 \n"
174 " bltz %0, 2f \n"
175 " sc.w %1, %2 \n"
176 " beqz %1, 1b \n"
177 "2: \n"
178 __WEAK_LLSC_MB
179 : "=&r" (result), "=&r" (temp), "+ZC" (v->counter)
180 : "r" (i));
181 }
182
183 return result;
184 }
185
186 #define arch_atomic_dec_if_positive(v) arch_atomic_sub_if_positive(1, v)
187
188 #ifdef CONFIG_64BIT
189
190 #define ATOMIC64_INIT(i) { (i) }
191
192 #define arch_atomic64_read(v) READ_ONCE((v)->counter)
193 #define arch_atomic64_set(v, i) WRITE_ONCE((v)->counter, (i))
194
195 #define ATOMIC64_OP(op, I, asm_op) \
196 static inline void arch_atomic64_##op(long i, atomic64_t *v) \
197 { \
198 __asm__ __volatile__( \
199 "am"#asm_op".d " " $zero, %1, %0 \n" \
200 : "+ZB" (v->counter) \
201 : "r" (I) \
202 : "memory"); \
203 }
204
205 #define ATOMIC64_OP_RETURN(op, I, asm_op, c_op, mb, suffix) \
206 static inline long arch_atomic64_##op##_return##suffix(long i, atomic64_t *v) \
207 { \
208 long result; \
209 __asm__ __volatile__( \
210 "am"#asm_op#mb".d " " %1, %2, %0 \n" \
211 : "+ZB" (v->counter), "=&r" (result) \
212 : "r" (I) \
213 : "memory"); \
214 \
215 return result c_op I; \
216 }
217
218 #define ATOMIC64_FETCH_OP(op, I, asm_op, mb, suffix) \
219 static inline long arch_atomic64_fetch_##op##suffix(long i, atomic64_t *v) \
220 { \
221 long result; \
222 \
223 __asm__ __volatile__( \
224 "am"#asm_op#mb".d " " %1, %2, %0 \n" \
225 : "+ZB" (v->counter), "=&r" (result) \
226 : "r" (I) \
227 : "memory"); \
228 \
229 return result; \
230 }
231
232 #define ATOMIC64_OPS(op, I, asm_op, c_op) \
233 ATOMIC64_OP(op, I, asm_op) \
234 ATOMIC64_OP_RETURN(op, I, asm_op, c_op, _db, ) \
235 ATOMIC64_OP_RETURN(op, I, asm_op, c_op, , _relaxed) \
236 ATOMIC64_FETCH_OP(op, I, asm_op, _db, ) \
237 ATOMIC64_FETCH_OP(op, I, asm_op, , _relaxed)
238
239 ATOMIC64_OPS(add, i, add, +)
240 ATOMIC64_OPS(sub, -i, add, +)
241
242 #define arch_atomic64_add_return arch_atomic64_add_return
243 #define arch_atomic64_add_return_acquire arch_atomic64_add_return
244 #define arch_atomic64_add_return_release arch_atomic64_add_return
245 #define arch_atomic64_add_return_relaxed arch_atomic64_add_return_relaxed
246 #define arch_atomic64_sub_return arch_atomic64_sub_return
247 #define arch_atomic64_sub_return_acquire arch_atomic64_sub_return
248 #define arch_atomic64_sub_return_release arch_atomic64_sub_return
249 #define arch_atomic64_sub_return_relaxed arch_atomic64_sub_return_relaxed
250 #define arch_atomic64_fetch_add arch_atomic64_fetch_add
251 #define arch_atomic64_fetch_add_acquire arch_atomic64_fetch_add
252 #define arch_atomic64_fetch_add_release arch_atomic64_fetch_add
253 #define arch_atomic64_fetch_add_relaxed arch_atomic64_fetch_add_relaxed
254 #define arch_atomic64_fetch_sub arch_atomic64_fetch_sub
255 #define arch_atomic64_fetch_sub_acquire arch_atomic64_fetch_sub
256 #define arch_atomic64_fetch_sub_release arch_atomic64_fetch_sub
257 #define arch_atomic64_fetch_sub_relaxed arch_atomic64_fetch_sub_relaxed
258
259 #undef ATOMIC64_OPS
260
261 #define ATOMIC64_OPS(op, I, asm_op) \
262 ATOMIC64_OP(op, I, asm_op) \
263 ATOMIC64_FETCH_OP(op, I, asm_op, _db, ) \
264 ATOMIC64_FETCH_OP(op, I, asm_op, , _relaxed)
265
266 ATOMIC64_OPS(and, i, and)
267 ATOMIC64_OPS(or, i, or)
268 ATOMIC64_OPS(xor, i, xor)
269
270 #define arch_atomic64_fetch_and arch_atomic64_fetch_and
271 #define arch_atomic64_fetch_and_acquire arch_atomic64_fetch_and
272 #define arch_atomic64_fetch_and_release arch_atomic64_fetch_and
273 #define arch_atomic64_fetch_and_relaxed arch_atomic64_fetch_and_relaxed
274 #define arch_atomic64_fetch_or arch_atomic64_fetch_or
275 #define arch_atomic64_fetch_or_acquire arch_atomic64_fetch_or
276 #define arch_atomic64_fetch_or_release arch_atomic64_fetch_or
277 #define arch_atomic64_fetch_or_relaxed arch_atomic64_fetch_or_relaxed
278 #define arch_atomic64_fetch_xor arch_atomic64_fetch_xor
279 #define arch_atomic64_fetch_xor_acquire arch_atomic64_fetch_xor
280 #define arch_atomic64_fetch_xor_release arch_atomic64_fetch_xor
281 #define arch_atomic64_fetch_xor_relaxed arch_atomic64_fetch_xor_relaxed
282
283 #undef ATOMIC64_OPS
284 #undef ATOMIC64_FETCH_OP
285 #undef ATOMIC64_OP_RETURN
286 #undef ATOMIC64_OP
287
288 static inline long arch_atomic64_fetch_add_unless(atomic64_t *v, long a, long u)
289 {
290 long prev, rc;
291
292 __asm__ __volatile__ (
293 "0: ll.d %[p], %[c]\n"
294 " beq %[p], %[u], 1f\n"
295 " add.d %[rc], %[p], %[a]\n"
296 " sc.d %[rc], %[c]\n"
297 " beqz %[rc], 0b\n"
298 " b 2f\n"
299 "1:\n"
300 __WEAK_LLSC_MB
301 "2:\n"
302 : [p]"=&r" (prev), [rc]"=&r" (rc),
303 [c] "=ZB" (v->counter)
304 : [a]"r" (a), [u]"r" (u)
305 : "memory");
306
307 return prev;
308 }
309 #define arch_atomic64_fetch_add_unless arch_atomic64_fetch_add_unless
310
311 static inline long arch_atomic64_sub_if_positive(long i, atomic64_t *v)
312 {
313 long result;
314 long temp;
315
316 if (__builtin_constant_p(i)) {
317 __asm__ __volatile__(
318 "1: ll.d %1, %2 # atomic64_sub_if_positive \n"
319 " addi.d %0, %1, %3 \n"
320 " move %1, %0 \n"
321 " bltz %0, 2f \n"
322 " sc.d %1, %2 \n"
323 " beqz %1, 1b \n"
324 "2: \n"
325 __WEAK_LLSC_MB
326 : "=&r" (result), "=&r" (temp), "+ZC" (v->counter)
327 : "I" (-i));
328 } else {
329 __asm__ __volatile__(
330 "1: ll.d %1, %2 # atomic64_sub_if_positive \n"
331 " sub.d %0, %1, %3 \n"
332 " move %1, %0 \n"
333 " bltz %0, 2f \n"
334 " sc.d %1, %2 \n"
335 " beqz %1, 1b \n"
336 "2: \n"
337 __WEAK_LLSC_MB
338 : "=&r" (result), "=&r" (temp), "+ZC" (v->counter)
339 : "r" (i));
340 }
341
342 return result;
343 }
344
345 #define arch_atomic64_dec_if_positive(v) arch_atomic64_sub_if_positive(1, v)
346
347 #endif /* CONFIG_64BIT */
348
349 #endif /* _ASM_ATOMIC_H */
350
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