xref: /freebsd/sys/powerpc/include/atomic.h (revision 52c2bb75163559a6e2866ad374a7de67a4ea1273)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2008 Marcel Moolenaar
5  * Copyright (c) 2001 Benno Rice
6  * Copyright (c) 2001 David E. O'Brien
7  * Copyright (c) 1998 Doug Rabson
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  * $FreeBSD$
32  */
33 
34 #ifndef _MACHINE_ATOMIC_H_
35 #define	_MACHINE_ATOMIC_H_
36 
37 #ifndef _SYS_CDEFS_H_
38 #error this file needs sys/cdefs.h as a prerequisite
39 #endif
40 
41 #include <sys/atomic_common.h>
42 
43 /*
44  * The __ATOMIC_REL/ACQ() macros provide memory barriers only in conjunction
45  * with the atomic lXarx/stXcx. sequences below. They are not exposed outside
46  * of this file. See also Appendix B.2 of Book II of the architecture manual.
47  *
48  * Note that not all Book-E processors accept the light-weight sync variant.
49  * In particular, early models of E500 cores are known to wedge. Bank on all
50  * 64-bit capable CPUs to accept lwsync properly and pressimize 32-bit CPUs
51  * to use the heavier-weight sync.
52  */
53 
54 #ifdef __powerpc64__
55 #define mb()		__asm __volatile("sync" : : : "memory")
56 #define rmb()		__asm __volatile("lwsync" : : : "memory")
57 #define wmb()		__asm __volatile("lwsync" : : : "memory")
58 #define __ATOMIC_REL()	__asm __volatile("lwsync" : : : "memory")
59 #define __ATOMIC_ACQ()	__asm __volatile("isync" : : : "memory")
60 #else
61 #define mb()		__asm __volatile("sync" : : : "memory")
62 #define rmb()		__asm __volatile("sync" : : : "memory")
63 #define wmb()		__asm __volatile("sync" : : : "memory")
64 #define __ATOMIC_REL()	__asm __volatile("sync" : : : "memory")
65 #define __ATOMIC_ACQ()	__asm __volatile("isync" : : : "memory")
66 #endif
67 
68 static __inline void
69 powerpc_lwsync(void)
70 {
71 
72 #ifdef __powerpc64__
73 	__asm __volatile("lwsync" : : : "memory");
74 #else
75 	__asm __volatile("sync" : : : "memory");
76 #endif
77 }
78 
79 /*
80  * atomic_add(p, v)
81  * { *p += v; }
82  */
83 
84 #define __atomic_add_int(p, v, t)				\
85     __asm __volatile(						\
86 	"1:	lwarx	%0, 0, %2\n"				\
87 	"	add	%0, %3, %0\n"				\
88 	"	stwcx.	%0, 0, %2\n"				\
89 	"	bne-	1b\n"					\
90 	: "=&r" (t), "=m" (*p)					\
91 	: "r" (p), "r" (v), "m" (*p)				\
92 	: "cr0", "memory")					\
93     /* __atomic_add_int */
94 
95 #ifdef __powerpc64__
96 #define __atomic_add_long(p, v, t)				\
97     __asm __volatile(						\
98 	"1:	ldarx	%0, 0, %2\n"				\
99 	"	add	%0, %3, %0\n"				\
100 	"	stdcx.	%0, 0, %2\n"				\
101 	"	bne-	1b\n"					\
102 	: "=&r" (t), "=m" (*p)					\
103 	: "r" (p), "r" (v), "m" (*p)				\
104 	: "cr0", "memory")					\
105     /* __atomic_add_long */
106 #else
107 #define	__atomic_add_long(p, v, t)				\
108     __asm __volatile(						\
109 	"1:	lwarx	%0, 0, %2\n"				\
110 	"	add	%0, %3, %0\n"				\
111 	"	stwcx.	%0, 0, %2\n"				\
112 	"	bne-	1b\n"					\
113 	: "=&r" (t), "=m" (*p)					\
114 	: "r" (p), "r" (v), "m" (*p)				\
115 	: "cr0", "memory")					\
116     /* __atomic_add_long */
117 #endif
118 
119 #define	_ATOMIC_ADD(type)					\
120     static __inline void					\
121     atomic_add_##type(volatile u_##type *p, u_##type v) {	\
122 	u_##type t;						\
123 	__atomic_add_##type(p, v, t);				\
124     }								\
125 								\
126     static __inline void					\
127     atomic_add_acq_##type(volatile u_##type *p, u_##type v) {	\
128 	u_##type t;						\
129 	__atomic_add_##type(p, v, t);				\
130 	__ATOMIC_ACQ();						\
131     }								\
132 								\
133     static __inline void					\
134     atomic_add_rel_##type(volatile u_##type *p, u_##type v) {	\
135 	u_##type t;						\
136 	__ATOMIC_REL();						\
137 	__atomic_add_##type(p, v, t);				\
138     }								\
139     /* _ATOMIC_ADD */
140 
141 _ATOMIC_ADD(int)
142 _ATOMIC_ADD(long)
143 
144 #define	atomic_add_32		atomic_add_int
145 #define	atomic_add_acq_32	atomic_add_acq_int
146 #define	atomic_add_rel_32	atomic_add_rel_int
147 
148 #ifdef __powerpc64__
149 #define	atomic_add_64		atomic_add_long
150 #define	atomic_add_acq_64	atomic_add_acq_long
151 #define	atomic_add_rel_64	atomic_add_rel_long
152 
153 #define	atomic_add_ptr		atomic_add_long
154 #define	atomic_add_acq_ptr	atomic_add_acq_long
155 #define	atomic_add_rel_ptr	atomic_add_rel_long
156 #else
157 #define	atomic_add_ptr		atomic_add_int
158 #define	atomic_add_acq_ptr	atomic_add_acq_int
159 #define	atomic_add_rel_ptr	atomic_add_rel_int
160 #endif
161 #undef _ATOMIC_ADD
162 #undef __atomic_add_long
163 #undef __atomic_add_int
164 
165 /*
166  * atomic_clear(p, v)
167  * { *p &= ~v; }
168  */
169 
170 #define __atomic_clear_int(p, v, t)				\
171     __asm __volatile(						\
172 	"1:	lwarx	%0, 0, %2\n"				\
173 	"	andc	%0, %0, %3\n"				\
174 	"	stwcx.	%0, 0, %2\n"				\
175 	"	bne-	1b\n"					\
176 	: "=&r" (t), "=m" (*p)					\
177 	: "r" (p), "r" (v), "m" (*p)				\
178 	: "cr0", "memory")					\
179     /* __atomic_clear_int */
180 
181 #ifdef __powerpc64__
182 #define __atomic_clear_long(p, v, t)				\
183     __asm __volatile(						\
184 	"1:	ldarx	%0, 0, %2\n"				\
185 	"	andc	%0, %0, %3\n"				\
186 	"	stdcx.	%0, 0, %2\n"				\
187 	"	bne-	1b\n"					\
188 	: "=&r" (t), "=m" (*p)					\
189 	: "r" (p), "r" (v), "m" (*p)				\
190 	: "cr0", "memory")					\
191     /* __atomic_clear_long */
192 #else
193 #define	__atomic_clear_long(p, v, t)				\
194     __asm __volatile(						\
195 	"1:	lwarx	%0, 0, %2\n"				\
196 	"	andc	%0, %0, %3\n"				\
197 	"	stwcx.	%0, 0, %2\n"				\
198 	"	bne-	1b\n"					\
199 	: "=&r" (t), "=m" (*p)					\
200 	: "r" (p), "r" (v), "m" (*p)				\
201 	: "cr0", "memory")					\
202     /* __atomic_clear_long */
203 #endif
204 
205 #define	_ATOMIC_CLEAR(type)					\
206     static __inline void					\
207     atomic_clear_##type(volatile u_##type *p, u_##type v) {	\
208 	u_##type t;						\
209 	__atomic_clear_##type(p, v, t);				\
210     }								\
211 								\
212     static __inline void					\
213     atomic_clear_acq_##type(volatile u_##type *p, u_##type v) {	\
214 	u_##type t;						\
215 	__atomic_clear_##type(p, v, t);				\
216 	__ATOMIC_ACQ();						\
217     }								\
218 								\
219     static __inline void					\
220     atomic_clear_rel_##type(volatile u_##type *p, u_##type v) {	\
221 	u_##type t;						\
222 	__ATOMIC_REL();						\
223 	__atomic_clear_##type(p, v, t);				\
224     }								\
225     /* _ATOMIC_CLEAR */
226 
227 
228 _ATOMIC_CLEAR(int)
229 _ATOMIC_CLEAR(long)
230 
231 #define	atomic_clear_32		atomic_clear_int
232 #define	atomic_clear_acq_32	atomic_clear_acq_int
233 #define	atomic_clear_rel_32	atomic_clear_rel_int
234 
235 #ifdef __powerpc64__
236 #define	atomic_clear_64		atomic_clear_long
237 #define	atomic_clear_acq_64	atomic_clear_acq_long
238 #define	atomic_clear_rel_64	atomic_clear_rel_long
239 
240 #define	atomic_clear_ptr	atomic_clear_long
241 #define	atomic_clear_acq_ptr	atomic_clear_acq_long
242 #define	atomic_clear_rel_ptr	atomic_clear_rel_long
243 #else
244 #define	atomic_clear_ptr	atomic_clear_int
245 #define	atomic_clear_acq_ptr	atomic_clear_acq_int
246 #define	atomic_clear_rel_ptr	atomic_clear_rel_int
247 #endif
248 #undef _ATOMIC_CLEAR
249 #undef __atomic_clear_long
250 #undef __atomic_clear_int
251 
252 /*
253  * atomic_cmpset(p, o, n)
254  */
255 /* TODO -- see below */
256 
257 /*
258  * atomic_load_acq(p)
259  */
260 /* TODO -- see below */
261 
262 /*
263  * atomic_readandclear(p)
264  */
265 /* TODO -- see below */
266 
267 /*
268  * atomic_set(p, v)
269  * { *p |= v; }
270  */
271 
272 #define __atomic_set_int(p, v, t)				\
273     __asm __volatile(						\
274 	"1:	lwarx	%0, 0, %2\n"				\
275 	"	or	%0, %3, %0\n"				\
276 	"	stwcx.	%0, 0, %2\n"				\
277 	"	bne-	1b\n"					\
278 	: "=&r" (t), "=m" (*p)					\
279 	: "r" (p), "r" (v), "m" (*p)				\
280 	: "cr0", "memory")					\
281     /* __atomic_set_int */
282 
283 #ifdef __powerpc64__
284 #define __atomic_set_long(p, v, t)				\
285     __asm __volatile(						\
286 	"1:	ldarx	%0, 0, %2\n"				\
287 	"	or	%0, %3, %0\n"				\
288 	"	stdcx.	%0, 0, %2\n"				\
289 	"	bne-	1b\n"					\
290 	: "=&r" (t), "=m" (*p)					\
291 	: "r" (p), "r" (v), "m" (*p)				\
292 	: "cr0", "memory")					\
293     /* __atomic_set_long */
294 #else
295 #define	__atomic_set_long(p, v, t)				\
296     __asm __volatile(						\
297 	"1:	lwarx	%0, 0, %2\n"				\
298 	"	or	%0, %3, %0\n"				\
299 	"	stwcx.	%0, 0, %2\n"				\
300 	"	bne-	1b\n"					\
301 	: "=&r" (t), "=m" (*p)					\
302 	: "r" (p), "r" (v), "m" (*p)				\
303 	: "cr0", "memory")					\
304     /* __atomic_set_long */
305 #endif
306 
307 #define	_ATOMIC_SET(type)					\
308     static __inline void					\
309     atomic_set_##type(volatile u_##type *p, u_##type v) {	\
310 	u_##type t;						\
311 	__atomic_set_##type(p, v, t);				\
312     }								\
313 								\
314     static __inline void					\
315     atomic_set_acq_##type(volatile u_##type *p, u_##type v) {	\
316 	u_##type t;						\
317 	__atomic_set_##type(p, v, t);				\
318 	__ATOMIC_ACQ();						\
319     }								\
320 								\
321     static __inline void					\
322     atomic_set_rel_##type(volatile u_##type *p, u_##type v) {	\
323 	u_##type t;						\
324 	__ATOMIC_REL();						\
325 	__atomic_set_##type(p, v, t);				\
326     }								\
327     /* _ATOMIC_SET */
328 
329 _ATOMIC_SET(int)
330 _ATOMIC_SET(long)
331 
332 #define	atomic_set_32		atomic_set_int
333 #define	atomic_set_acq_32	atomic_set_acq_int
334 #define	atomic_set_rel_32	atomic_set_rel_int
335 
336 #ifdef __powerpc64__
337 #define	atomic_set_64		atomic_set_long
338 #define	atomic_set_acq_64	atomic_set_acq_long
339 #define	atomic_set_rel_64	atomic_set_rel_long
340 
341 #define	atomic_set_ptr		atomic_set_long
342 #define	atomic_set_acq_ptr	atomic_set_acq_long
343 #define	atomic_set_rel_ptr	atomic_set_rel_long
344 #else
345 #define	atomic_set_ptr		atomic_set_int
346 #define	atomic_set_acq_ptr	atomic_set_acq_int
347 #define	atomic_set_rel_ptr	atomic_set_rel_int
348 #endif
349 #undef _ATOMIC_SET
350 #undef __atomic_set_long
351 #undef __atomic_set_int
352 
353 /*
354  * atomic_subtract(p, v)
355  * { *p -= v; }
356  */
357 
358 #define __atomic_subtract_int(p, v, t)				\
359     __asm __volatile(						\
360 	"1:	lwarx	%0, 0, %2\n"				\
361 	"	subf	%0, %3, %0\n"				\
362 	"	stwcx.	%0, 0, %2\n"				\
363 	"	bne-	1b\n"					\
364 	: "=&r" (t), "=m" (*p)					\
365 	: "r" (p), "r" (v), "m" (*p)				\
366 	: "cr0", "memory")					\
367     /* __atomic_subtract_int */
368 
369 #ifdef __powerpc64__
370 #define __atomic_subtract_long(p, v, t)				\
371     __asm __volatile(						\
372 	"1:	ldarx	%0, 0, %2\n"				\
373 	"	subf	%0, %3, %0\n"				\
374 	"	stdcx.	%0, 0, %2\n"				\
375 	"	bne-	1b\n"					\
376 	: "=&r" (t), "=m" (*p)					\
377 	: "r" (p), "r" (v), "m" (*p)				\
378 	: "cr0", "memory")					\
379     /* __atomic_subtract_long */
380 #else
381 #define	__atomic_subtract_long(p, v, t)				\
382     __asm __volatile(						\
383 	"1:	lwarx	%0, 0, %2\n"				\
384 	"	subf	%0, %3, %0\n"				\
385 	"	stwcx.	%0, 0, %2\n"				\
386 	"	bne-	1b\n"					\
387 	: "=&r" (t), "=m" (*p)					\
388 	: "r" (p), "r" (v), "m" (*p)				\
389 	: "cr0", "memory")					\
390     /* __atomic_subtract_long */
391 #endif
392 
393 #define	_ATOMIC_SUBTRACT(type)						\
394     static __inline void						\
395     atomic_subtract_##type(volatile u_##type *p, u_##type v) {		\
396 	u_##type t;							\
397 	__atomic_subtract_##type(p, v, t);				\
398     }									\
399 									\
400     static __inline void						\
401     atomic_subtract_acq_##type(volatile u_##type *p, u_##type v) {	\
402 	u_##type t;							\
403 	__atomic_subtract_##type(p, v, t);				\
404 	__ATOMIC_ACQ();							\
405     }									\
406 									\
407     static __inline void						\
408     atomic_subtract_rel_##type(volatile u_##type *p, u_##type v) {	\
409 	u_##type t;							\
410 	__ATOMIC_REL();							\
411 	__atomic_subtract_##type(p, v, t);				\
412     }									\
413     /* _ATOMIC_SUBTRACT */
414 
415 _ATOMIC_SUBTRACT(int)
416 _ATOMIC_SUBTRACT(long)
417 
418 #define	atomic_subtract_32	atomic_subtract_int
419 #define	atomic_subtract_acq_32	atomic_subtract_acq_int
420 #define	atomic_subtract_rel_32	atomic_subtract_rel_int
421 
422 #ifdef __powerpc64__
423 #define	atomic_subtract_64	atomic_subtract_long
424 #define	atomic_subtract_acq_64	atomic_subract_acq_long
425 #define	atomic_subtract_rel_64	atomic_subtract_rel_long
426 
427 #define	atomic_subtract_ptr	atomic_subtract_long
428 #define	atomic_subtract_acq_ptr	atomic_subtract_acq_long
429 #define	atomic_subtract_rel_ptr	atomic_subtract_rel_long
430 #else
431 #define	atomic_subtract_ptr	atomic_subtract_int
432 #define	atomic_subtract_acq_ptr	atomic_subtract_acq_int
433 #define	atomic_subtract_rel_ptr	atomic_subtract_rel_int
434 #endif
435 #undef _ATOMIC_SUBTRACT
436 #undef __atomic_subtract_long
437 #undef __atomic_subtract_int
438 
439 /*
440  * atomic_store_rel(p, v)
441  */
442 /* TODO -- see below */
443 
444 /*
445  * Old/original implementations that still need revisiting.
446  */
447 
448 static __inline u_int
449 atomic_readandclear_int(volatile u_int *addr)
450 {
451 	u_int result,temp;
452 
453 	__asm __volatile (
454 		"\tsync\n"			/* drain writes */
455 		"1:\tlwarx %0, 0, %3\n\t"	/* load old value */
456 		"li %1, 0\n\t"			/* load new value */
457 		"stwcx. %1, 0, %3\n\t"      	/* attempt to store */
458 		"bne- 1b\n\t"			/* spin if failed */
459 		: "=&r"(result), "=&r"(temp), "=m" (*addr)
460 		: "r" (addr), "m" (*addr)
461 		: "cr0", "memory");
462 
463 	return (result);
464 }
465 
466 #ifdef __powerpc64__
467 static __inline u_long
468 atomic_readandclear_long(volatile u_long *addr)
469 {
470 	u_long result,temp;
471 
472 	__asm __volatile (
473 		"\tsync\n"			/* drain writes */
474 		"1:\tldarx %0, 0, %3\n\t"	/* load old value */
475 		"li %1, 0\n\t"			/* load new value */
476 		"stdcx. %1, 0, %3\n\t"      	/* attempt to store */
477 		"bne- 1b\n\t"			/* spin if failed */
478 		: "=&r"(result), "=&r"(temp), "=m" (*addr)
479 		: "r" (addr), "m" (*addr)
480 		: "cr0", "memory");
481 
482 	return (result);
483 }
484 #endif
485 
486 #define	atomic_readandclear_32		atomic_readandclear_int
487 
488 #ifdef __powerpc64__
489 #define	atomic_readandclear_64		atomic_readandclear_long
490 
491 #define	atomic_readandclear_ptr		atomic_readandclear_long
492 #else
493 static __inline u_long
494 atomic_readandclear_long(volatile u_long *addr)
495 {
496 
497 	return ((u_long)atomic_readandclear_int((volatile u_int *)addr));
498 }
499 
500 #define	atomic_readandclear_ptr		atomic_readandclear_int
501 #endif
502 
503 /*
504  * We assume that a = b will do atomic loads and stores.
505  */
506 #define	ATOMIC_STORE_LOAD(TYPE)					\
507 static __inline u_##TYPE					\
508 atomic_load_acq_##TYPE(volatile u_##TYPE *p)			\
509 {								\
510 	u_##TYPE v;						\
511 								\
512 	v = *p;							\
513 	powerpc_lwsync();					\
514 	return (v);						\
515 }								\
516 								\
517 static __inline void						\
518 atomic_store_rel_##TYPE(volatile u_##TYPE *p, u_##TYPE v)	\
519 {								\
520 								\
521 	powerpc_lwsync();					\
522 	*p = v;							\
523 }
524 
525 ATOMIC_STORE_LOAD(int)
526 
527 #define	atomic_load_acq_32	atomic_load_acq_int
528 #define	atomic_store_rel_32	atomic_store_rel_int
529 
530 #ifdef __powerpc64__
531 ATOMIC_STORE_LOAD(long)
532 
533 #define	atomic_load_acq_64	atomic_load_acq_long
534 #define	atomic_store_rel_64	atomic_store_rel_long
535 
536 #define	atomic_load_acq_ptr	atomic_load_acq_long
537 #define	atomic_store_rel_ptr	atomic_store_rel_long
538 #else
539 static __inline u_long
540 atomic_load_acq_long(volatile u_long *addr)
541 {
542 
543 	return ((u_long)atomic_load_acq_int((volatile u_int *)addr));
544 }
545 
546 static __inline void
547 atomic_store_rel_long(volatile u_long *addr, u_long val)
548 {
549 
550 	atomic_store_rel_int((volatile u_int *)addr, (u_int)val);
551 }
552 
553 #define	atomic_load_acq_ptr	atomic_load_acq_int
554 #define	atomic_store_rel_ptr	atomic_store_rel_int
555 #endif
556 #undef ATOMIC_STORE_LOAD
557 
558 /*
559  * Atomically compare the value stored at *p with cmpval and if the
560  * two values are equal, update the value of *p with newval. Returns
561  * zero if the compare failed, nonzero otherwise.
562  */
563 static __inline int
564 atomic_cmpset_int(volatile u_int* p, u_int cmpval, u_int newval)
565 {
566 	int	ret;
567 
568 	__asm __volatile (
569 		"1:\tlwarx %0, 0, %2\n\t"	/* load old value */
570 		"cmplw %3, %0\n\t"		/* compare */
571 		"bne 2f\n\t"			/* exit if not equal */
572 		"stwcx. %4, 0, %2\n\t"      	/* attempt to store */
573 		"bne- 1b\n\t"			/* spin if failed */
574 		"li %0, 1\n\t"			/* success - retval = 1 */
575 		"b 3f\n\t"			/* we've succeeded */
576 		"2:\n\t"
577 		"stwcx. %0, 0, %2\n\t"       	/* clear reservation (74xx) */
578 		"li %0, 0\n\t"			/* failure - retval = 0 */
579 		"3:\n\t"
580 		: "=&r" (ret), "=m" (*p)
581 		: "r" (p), "r" (cmpval), "r" (newval), "m" (*p)
582 		: "cr0", "memory");
583 
584 	return (ret);
585 }
586 static __inline int
587 atomic_cmpset_long(volatile u_long* p, u_long cmpval, u_long newval)
588 {
589 	int ret;
590 
591 	__asm __volatile (
592 	    #ifdef __powerpc64__
593 		"1:\tldarx %0, 0, %2\n\t"	/* load old value */
594 		"cmpld %3, %0\n\t"		/* compare */
595 		"bne 2f\n\t"			/* exit if not equal */
596 		"stdcx. %4, 0, %2\n\t"		/* attempt to store */
597 	    #else
598 		"1:\tlwarx %0, 0, %2\n\t"	/* load old value */
599 		"cmplw %3, %0\n\t"		/* compare */
600 		"bne 2f\n\t"			/* exit if not equal */
601 		"stwcx. %4, 0, %2\n\t"		/* attempt to store */
602 	    #endif
603 		"bne- 1b\n\t"			/* spin if failed */
604 		"li %0, 1\n\t"			/* success - retval = 1 */
605 		"b 3f\n\t"			/* we've succeeded */
606 		"2:\n\t"
607 	    #ifdef __powerpc64__
608 		"stdcx. %0, 0, %2\n\t"		/* clear reservation (74xx) */
609 	    #else
610 		"stwcx. %0, 0, %2\n\t"		/* clear reservation (74xx) */
611 	    #endif
612 		"li %0, 0\n\t"			/* failure - retval = 0 */
613 		"3:\n\t"
614 		: "=&r" (ret), "=m" (*p)
615 		: "r" (p), "r" (cmpval), "r" (newval), "m" (*p)
616 		: "cr0", "memory");
617 
618 	return (ret);
619 }
620 
621 static __inline int
622 atomic_cmpset_acq_int(volatile u_int *p, u_int cmpval, u_int newval)
623 {
624 	int retval;
625 
626 	retval = atomic_cmpset_int(p, cmpval, newval);
627 	__ATOMIC_ACQ();
628 	return (retval);
629 }
630 
631 static __inline int
632 atomic_cmpset_rel_int(volatile u_int *p, u_int cmpval, u_int newval)
633 {
634 	__ATOMIC_REL();
635 	return (atomic_cmpset_int(p, cmpval, newval));
636 }
637 
638 static __inline int
639 atomic_cmpset_acq_long(volatile u_long *p, u_long cmpval, u_long newval)
640 {
641 	u_long retval;
642 
643 	retval = atomic_cmpset_long(p, cmpval, newval);
644 	__ATOMIC_ACQ();
645 	return (retval);
646 }
647 
648 static __inline int
649 atomic_cmpset_rel_long(volatile u_long *p, u_long cmpval, u_long newval)
650 {
651 	__ATOMIC_REL();
652 	return (atomic_cmpset_long(p, cmpval, newval));
653 }
654 
655 #define	atomic_cmpset_32	atomic_cmpset_int
656 #define	atomic_cmpset_acq_32	atomic_cmpset_acq_int
657 #define	atomic_cmpset_rel_32	atomic_cmpset_rel_int
658 
659 #ifdef __powerpc64__
660 #define	atomic_cmpset_64	atomic_cmpset_long
661 #define	atomic_cmpset_acq_64	atomic_cmpset_acq_long
662 #define	atomic_cmpset_rel_64	atomic_cmpset_rel_long
663 
664 #define	atomic_cmpset_ptr	atomic_cmpset_long
665 #define	atomic_cmpset_acq_ptr	atomic_cmpset_acq_long
666 #define	atomic_cmpset_rel_ptr	atomic_cmpset_rel_long
667 #else
668 #define	atomic_cmpset_ptr	atomic_cmpset_int
669 #define	atomic_cmpset_acq_ptr	atomic_cmpset_acq_int
670 #define	atomic_cmpset_rel_ptr	atomic_cmpset_rel_int
671 #endif
672 
673 /*
674  * Atomically compare the value stored at *p with *cmpval and if the
675  * two values are equal, update the value of *p with newval. Returns
676  * zero if the compare failed and sets *cmpval to the read value from *p,
677  * nonzero otherwise.
678  */
679 static __inline int
680 atomic_fcmpset_int(volatile u_int *p, u_int *cmpval, u_int newval)
681 {
682 	int	ret;
683 
684 	__asm __volatile (
685 		"lwarx %0, 0, %3\n\t"	/* load old value */
686 		"cmplw %4, %0\n\t"		/* compare */
687 		"bne 1f\n\t"			/* exit if not equal */
688 		"stwcx. %5, 0, %3\n\t"      	/* attempt to store */
689 		"bne- 1f\n\t"			/* exit if failed */
690 		"li %0, 1\n\t"			/* success - retval = 1 */
691 		"b 2f\n\t"			/* we've succeeded */
692 		"1:\n\t"
693 		"stwcx. %0, 0, %3\n\t"       	/* clear reservation (74xx) */
694 		"stwx %0, 0, %7\n\t"
695 		"li %0, 0\n\t"			/* failure - retval = 0 */
696 		"2:\n\t"
697 		: "=&r" (ret), "=m" (*p), "=m" (*cmpval)
698 		: "r" (p), "r" (*cmpval), "r" (newval), "m" (*p), "r"(cmpval)
699 		: "cr0", "memory");
700 
701 	return (ret);
702 }
703 static __inline int
704 atomic_fcmpset_long(volatile u_long *p, u_long *cmpval, u_long newval)
705 {
706 	int ret;
707 
708 	__asm __volatile (
709 	    #ifdef __powerpc64__
710 		"ldarx %0, 0, %3\n\t"	/* load old value */
711 		"cmpld %4, %0\n\t"		/* compare */
712 		"bne 1f\n\t"			/* exit if not equal */
713 		"stdcx. %5, 0, %3\n\t"		/* attempt to store */
714 	    #else
715 		"lwarx %0, 0, %3\n\t"	/* load old value */
716 		"cmplw %4, %0\n\t"		/* compare */
717 		"bne 1f\n\t"			/* exit if not equal */
718 		"stwcx. %5, 0, %3\n\t"		/* attempt to store */
719 	    #endif
720 		"bne- 1f\n\t"			/* exit if failed */
721 		"li %0, 1\n\t"			/* success - retval = 1 */
722 		"b 2f\n\t"			/* we've succeeded */
723 		"1:\n\t"
724 	    #ifdef __powerpc64__
725 		"stdcx. %0, 0, %3\n\t"		/* clear reservation (74xx) */
726 		"stdx %0, 0, %7\n\t"
727 	    #else
728 		"stwcx. %0, 0, %3\n\t"		/* clear reservation (74xx) */
729 		"stwx %0, 0, %7\n\t"
730 	    #endif
731 		"li %0, 0\n\t"			/* failure - retval = 0 */
732 		"2:\n\t"
733 		: "=&r" (ret), "=m" (*p), "=m" (*cmpval)
734 		: "r" (p), "r" (*cmpval), "r" (newval), "m" (*p), "r"(cmpval)
735 		: "cr0", "memory");
736 
737 	return (ret);
738 }
739 
740 static __inline int
741 atomic_fcmpset_acq_int(volatile u_int *p, u_int *cmpval, u_int newval)
742 {
743 	int retval;
744 
745 	retval = atomic_fcmpset_int(p, cmpval, newval);
746 	__ATOMIC_ACQ();
747 	return (retval);
748 }
749 
750 static __inline int
751 atomic_fcmpset_rel_int(volatile u_int *p, u_int *cmpval, u_int newval)
752 {
753 	__ATOMIC_REL();
754 	return (atomic_fcmpset_int(p, cmpval, newval));
755 }
756 
757 static __inline int
758 atomic_fcmpset_acq_long(volatile u_long *p, u_long *cmpval, u_long newval)
759 {
760 	u_long retval;
761 
762 	retval = atomic_fcmpset_long(p, cmpval, newval);
763 	__ATOMIC_ACQ();
764 	return (retval);
765 }
766 
767 static __inline int
768 atomic_fcmpset_rel_long(volatile u_long *p, u_long *cmpval, u_long newval)
769 {
770 	__ATOMIC_REL();
771 	return (atomic_fcmpset_long(p, cmpval, newval));
772 }
773 
774 #define	atomic_fcmpset_32	atomic_fcmpset_int
775 #define	atomic_fcmpset_acq_32	atomic_fcmpset_acq_int
776 #define	atomic_fcmpset_rel_32	atomic_fcmpset_rel_int
777 
778 #ifdef __powerpc64__
779 #define	atomic_fcmpset_64	atomic_fcmpset_long
780 #define	atomic_fcmpset_acq_64	atomic_fcmpset_acq_long
781 #define	atomic_fcmpset_rel_64	atomic_fcmpset_rel_long
782 
783 #define	atomic_fcmpset_ptr	atomic_fcmpset_long
784 #define	atomic_fcmpset_acq_ptr	atomic_fcmpset_acq_long
785 #define	atomic_fcmpset_rel_ptr	atomic_fcmpset_rel_long
786 #else
787 #define	atomic_fcmpset_ptr	atomic_fcmpset_int
788 #define	atomic_fcmpset_acq_ptr	atomic_fcmpset_acq_int
789 #define	atomic_fcmpset_rel_ptr	atomic_fcmpset_rel_int
790 #endif
791 
792 static __inline u_int
793 atomic_fetchadd_int(volatile u_int *p, u_int v)
794 {
795 	u_int value;
796 
797 	do {
798 		value = *p;
799 	} while (!atomic_cmpset_int(p, value, value + v));
800 	return (value);
801 }
802 
803 static __inline u_long
804 atomic_fetchadd_long(volatile u_long *p, u_long v)
805 {
806 	u_long value;
807 
808 	do {
809 		value = *p;
810 	} while (!atomic_cmpset_long(p, value, value + v));
811 	return (value);
812 }
813 
814 static __inline u_int
815 atomic_swap_32(volatile u_int *p, u_int v)
816 {
817 	u_int prev;
818 
819 	__asm __volatile(
820 	"1:	lwarx	%0,0,%2\n"
821 	"	stwcx.	%3,0,%2\n"
822 	"	bne-	1b\n"
823 	: "=&r" (prev), "+m" (*(volatile u_int *)p)
824 	: "r" (p), "r" (v)
825 	: "cr0", "memory");
826 
827 	return (prev);
828 }
829 
830 #ifdef __powerpc64__
831 static __inline u_long
832 atomic_swap_64(volatile u_long *p, u_long v)
833 {
834 	u_long prev;
835 
836 	__asm __volatile(
837 	"1:	ldarx	%0,0,%2\n"
838 	"	stdcx.	%3,0,%2\n"
839 	"	bne-	1b\n"
840 	: "=&r" (prev), "+m" (*(volatile u_long *)p)
841 	: "r" (p), "r" (v)
842 	: "cr0", "memory");
843 
844 	return (prev);
845 }
846 #endif
847 
848 #define	atomic_fetchadd_32	atomic_fetchadd_int
849 #define	atomic_swap_int		atomic_swap_32
850 
851 #ifdef __powerpc64__
852 #define	atomic_fetchadd_64	atomic_fetchadd_long
853 #define	atomic_swap_long	atomic_swap_64
854 #define	atomic_swap_ptr		atomic_swap_64
855 #else
856 #define	atomic_swap_long(p,v)	atomic_swap_32((volatile u_int *)(p), v)
857 #define	atomic_swap_ptr(p,v)	atomic_swap_32((volatile u_int *)(p), v)
858 #endif
859 
860 #undef __ATOMIC_REL
861 #undef __ATOMIC_ACQ
862 
863 static __inline void
864 atomic_thread_fence_acq(void)
865 {
866 
867 	powerpc_lwsync();
868 }
869 
870 static __inline void
871 atomic_thread_fence_rel(void)
872 {
873 
874 	powerpc_lwsync();
875 }
876 
877 static __inline void
878 atomic_thread_fence_acq_rel(void)
879 {
880 
881 	powerpc_lwsync();
882 }
883 
884 static __inline void
885 atomic_thread_fence_seq_cst(void)
886 {
887 
888 	__asm __volatile("sync" : : : "memory");
889 }
890 
891 #endif /* ! _MACHINE_ATOMIC_H_ */
892