Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / arch / mips / include / asm / bitops.h
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1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
6 * Copyright (c) 1994 - 1997, 99, 2000, 06, 07 Ralf Baechle (ralf@linux-mips.org)
7 * Copyright (c) 1999, 2000 Silicon Graphics, Inc.
8 */
9 #ifndef _ASM_BITOPS_H
10 #define _ASM_BITOPS_H
12 #ifndef _LINUX_BITOPS_H
13 #error only <linux/bitops.h> can be included directly
14 #endif
16 #include <linux/compiler.h>
17 #include <linux/types.h>
18 #include <asm/barrier.h>
19 #include <asm/byteorder.h> /* sigh ... */
20 #include <asm/compiler.h>
21 #include <asm/cpu-features.h>
22 #include <asm/llsc.h>
23 #include <asm/sgidefs.h>
24 #include <asm/war.h>
27 * These are the "slower" versions of the functions and are in bitops.c.
28 * These functions call raw_local_irq_{save,restore}().
30 void __mips_set_bit(unsigned long nr, volatile unsigned long *addr);
31 void __mips_clear_bit(unsigned long nr, volatile unsigned long *addr);
32 void __mips_change_bit(unsigned long nr, volatile unsigned long *addr);
33 int __mips_test_and_set_bit(unsigned long nr,
34 volatile unsigned long *addr);
35 int __mips_test_and_set_bit_lock(unsigned long nr,
36 volatile unsigned long *addr);
37 int __mips_test_and_clear_bit(unsigned long nr,
38 volatile unsigned long *addr);
39 int __mips_test_and_change_bit(unsigned long nr,
40 volatile unsigned long *addr);
44 * set_bit - Atomically set a bit in memory
45 * @nr: the bit to set
46 * @addr: the address to start counting from
48 * This function is atomic and may not be reordered. See __set_bit()
49 * if you do not require the atomic guarantees.
50 * Note that @nr may be almost arbitrarily large; this function is not
51 * restricted to acting on a single-word quantity.
53 static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
55 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
56 int bit = nr & SZLONG_MASK;
57 unsigned long temp;
59 if (kernel_uses_llsc && R10000_LLSC_WAR) {
60 __asm__ __volatile__(
61 " .set arch=r4000 \n"
62 "1: " __LL "%0, %1 # set_bit \n"
63 " or %0, %2 \n"
64 " " __SC "%0, %1 \n"
65 " beqzl %0, 1b \n"
66 " .set mips0 \n"
67 : "=&r" (temp), "=" GCC_OFF_SMALL_ASM() (*m)
68 : "ir" (1UL << bit), GCC_OFF_SMALL_ASM() (*m));
69 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
70 } else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
71 do {
72 __asm__ __volatile__(
73 " " __LL "%0, %1 # set_bit \n"
74 " " __INS "%0, %3, %2, 1 \n"
75 " " __SC "%0, %1 \n"
76 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
77 : "ir" (bit), "r" (~0));
78 } while (unlikely(!temp));
79 #endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
80 } else if (kernel_uses_llsc) {
81 do {
82 __asm__ __volatile__(
83 " .set "MIPS_ISA_ARCH_LEVEL" \n"
84 " " __LL "%0, %1 # set_bit \n"
85 " or %0, %2 \n"
86 " " __SC "%0, %1 \n"
87 " .set mips0 \n"
88 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
89 : "ir" (1UL << bit));
90 } while (unlikely(!temp));
91 } else
92 __mips_set_bit(nr, addr);
96 * clear_bit - Clears a bit in memory
97 * @nr: Bit to clear
98 * @addr: Address to start counting from
100 * clear_bit() is atomic and may not be reordered. However, it does
101 * not contain a memory barrier, so if it is used for locking purposes,
102 * you should call smp_mb__before_atomic() and/or smp_mb__after_atomic()
103 * in order to ensure changes are visible on other processors.
105 static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
107 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
108 int bit = nr & SZLONG_MASK;
109 unsigned long temp;
111 if (kernel_uses_llsc && R10000_LLSC_WAR) {
112 __asm__ __volatile__(
113 " .set arch=r4000 \n"
114 "1: " __LL "%0, %1 # clear_bit \n"
115 " and %0, %2 \n"
116 " " __SC "%0, %1 \n"
117 " beqzl %0, 1b \n"
118 " .set mips0 \n"
119 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
120 : "ir" (~(1UL << bit)));
121 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
122 } else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
123 do {
124 __asm__ __volatile__(
125 " " __LL "%0, %1 # clear_bit \n"
126 " " __INS "%0, $0, %2, 1 \n"
127 " " __SC "%0, %1 \n"
128 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
129 : "ir" (bit));
130 } while (unlikely(!temp));
131 #endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
132 } else if (kernel_uses_llsc) {
133 do {
134 __asm__ __volatile__(
135 " .set "MIPS_ISA_ARCH_LEVEL" \n"
136 " " __LL "%0, %1 # clear_bit \n"
137 " and %0, %2 \n"
138 " " __SC "%0, %1 \n"
139 " .set mips0 \n"
140 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
141 : "ir" (~(1UL << bit)));
142 } while (unlikely(!temp));
143 } else
144 __mips_clear_bit(nr, addr);
148 * clear_bit_unlock - Clears a bit in memory
149 * @nr: Bit to clear
150 * @addr: Address to start counting from
152 * clear_bit() is atomic and implies release semantics before the memory
153 * operation. It can be used for an unlock.
155 static inline void clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
157 smp_mb__before_atomic();
158 clear_bit(nr, addr);
162 * change_bit - Toggle a bit in memory
163 * @nr: Bit to change
164 * @addr: Address to start counting from
166 * change_bit() is atomic and may not be reordered.
167 * Note that @nr may be almost arbitrarily large; this function is not
168 * restricted to acting on a single-word quantity.
170 static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
172 int bit = nr & SZLONG_MASK;
174 if (kernel_uses_llsc && R10000_LLSC_WAR) {
175 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
176 unsigned long temp;
178 __asm__ __volatile__(
179 " .set arch=r4000 \n"
180 "1: " __LL "%0, %1 # change_bit \n"
181 " xor %0, %2 \n"
182 " " __SC "%0, %1 \n"
183 " beqzl %0, 1b \n"
184 " .set mips0 \n"
185 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
186 : "ir" (1UL << bit));
187 } else if (kernel_uses_llsc) {
188 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
189 unsigned long temp;
191 do {
192 __asm__ __volatile__(
193 " .set "MIPS_ISA_ARCH_LEVEL" \n"
194 " " __LL "%0, %1 # change_bit \n"
195 " xor %0, %2 \n"
196 " " __SC "%0, %1 \n"
197 " .set mips0 \n"
198 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
199 : "ir" (1UL << bit));
200 } while (unlikely(!temp));
201 } else
202 __mips_change_bit(nr, addr);
206 * test_and_set_bit - Set a bit and return its old value
207 * @nr: Bit to set
208 * @addr: Address to count from
210 * This operation is atomic and cannot be reordered.
211 * It also implies a memory barrier.
213 static inline int test_and_set_bit(unsigned long nr,
214 volatile unsigned long *addr)
216 int bit = nr & SZLONG_MASK;
217 unsigned long res;
219 smp_mb__before_llsc();
221 if (kernel_uses_llsc && R10000_LLSC_WAR) {
222 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
223 unsigned long temp;
225 __asm__ __volatile__(
226 " .set arch=r4000 \n"
227 "1: " __LL "%0, %1 # test_and_set_bit \n"
228 " or %2, %0, %3 \n"
229 " " __SC "%2, %1 \n"
230 " beqzl %2, 1b \n"
231 " and %2, %0, %3 \n"
232 " .set mips0 \n"
233 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
234 : "r" (1UL << bit)
235 : "memory");
236 } else if (kernel_uses_llsc) {
237 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
238 unsigned long temp;
240 do {
241 __asm__ __volatile__(
242 " .set "MIPS_ISA_ARCH_LEVEL" \n"
243 " " __LL "%0, %1 # test_and_set_bit \n"
244 " or %2, %0, %3 \n"
245 " " __SC "%2, %1 \n"
246 " .set mips0 \n"
247 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
248 : "r" (1UL << bit)
249 : "memory");
250 } while (unlikely(!res));
252 res = temp & (1UL << bit);
253 } else
254 res = __mips_test_and_set_bit(nr, addr);
256 smp_llsc_mb();
258 return res != 0;
262 * test_and_set_bit_lock - Set a bit and return its old value
263 * @nr: Bit to set
264 * @addr: Address to count from
266 * This operation is atomic and implies acquire ordering semantics
267 * after the memory operation.
269 static inline int test_and_set_bit_lock(unsigned long nr,
270 volatile unsigned long *addr)
272 int bit = nr & SZLONG_MASK;
273 unsigned long res;
275 if (kernel_uses_llsc && R10000_LLSC_WAR) {
276 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
277 unsigned long temp;
279 __asm__ __volatile__(
280 " .set arch=r4000 \n"
281 "1: " __LL "%0, %1 # test_and_set_bit \n"
282 " or %2, %0, %3 \n"
283 " " __SC "%2, %1 \n"
284 " beqzl %2, 1b \n"
285 " and %2, %0, %3 \n"
286 " .set mips0 \n"
287 : "=&r" (temp), "+m" (*m), "=&r" (res)
288 : "r" (1UL << bit)
289 : "memory");
290 } else if (kernel_uses_llsc) {
291 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
292 unsigned long temp;
294 do {
295 __asm__ __volatile__(
296 " .set "MIPS_ISA_ARCH_LEVEL" \n"
297 " " __LL "%0, %1 # test_and_set_bit \n"
298 " or %2, %0, %3 \n"
299 " " __SC "%2, %1 \n"
300 " .set mips0 \n"
301 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
302 : "r" (1UL << bit)
303 : "memory");
304 } while (unlikely(!res));
306 res = temp & (1UL << bit);
307 } else
308 res = __mips_test_and_set_bit_lock(nr, addr);
310 smp_llsc_mb();
312 return res != 0;
315 * test_and_clear_bit - Clear a bit and return its old value
316 * @nr: Bit to clear
317 * @addr: Address to count from
319 * This operation is atomic and cannot be reordered.
320 * It also implies a memory barrier.
322 static inline int test_and_clear_bit(unsigned long nr,
323 volatile unsigned long *addr)
325 int bit = nr & SZLONG_MASK;
326 unsigned long res;
328 smp_mb__before_llsc();
330 if (kernel_uses_llsc && R10000_LLSC_WAR) {
331 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
332 unsigned long temp;
334 __asm__ __volatile__(
335 " .set arch=r4000 \n"
336 "1: " __LL "%0, %1 # test_and_clear_bit \n"
337 " or %2, %0, %3 \n"
338 " xor %2, %3 \n"
339 " " __SC "%2, %1 \n"
340 " beqzl %2, 1b \n"
341 " and %2, %0, %3 \n"
342 " .set mips0 \n"
343 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
344 : "r" (1UL << bit)
345 : "memory");
346 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
347 } else if (kernel_uses_llsc && __builtin_constant_p(nr)) {
348 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
349 unsigned long temp;
351 do {
352 __asm__ __volatile__(
353 " " __LL "%0, %1 # test_and_clear_bit \n"
354 " " __EXT "%2, %0, %3, 1 \n"
355 " " __INS "%0, $0, %3, 1 \n"
356 " " __SC "%0, %1 \n"
357 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
358 : "ir" (bit)
359 : "memory");
360 } while (unlikely(!temp));
361 #endif
362 } else if (kernel_uses_llsc) {
363 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
364 unsigned long temp;
366 do {
367 __asm__ __volatile__(
368 " .set "MIPS_ISA_ARCH_LEVEL" \n"
369 " " __LL "%0, %1 # test_and_clear_bit \n"
370 " or %2, %0, %3 \n"
371 " xor %2, %3 \n"
372 " " __SC "%2, %1 \n"
373 " .set mips0 \n"
374 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
375 : "r" (1UL << bit)
376 : "memory");
377 } while (unlikely(!res));
379 res = temp & (1UL << bit);
380 } else
381 res = __mips_test_and_clear_bit(nr, addr);
383 smp_llsc_mb();
385 return res != 0;
389 * test_and_change_bit - Change a bit and return its old value
390 * @nr: Bit to change
391 * @addr: Address to count from
393 * This operation is atomic and cannot be reordered.
394 * It also implies a memory barrier.
396 static inline int test_and_change_bit(unsigned long nr,
397 volatile unsigned long *addr)
399 int bit = nr & SZLONG_MASK;
400 unsigned long res;
402 smp_mb__before_llsc();
404 if (kernel_uses_llsc && R10000_LLSC_WAR) {
405 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
406 unsigned long temp;
408 __asm__ __volatile__(
409 " .set arch=r4000 \n"
410 "1: " __LL "%0, %1 # test_and_change_bit \n"
411 " xor %2, %0, %3 \n"
412 " " __SC "%2, %1 \n"
413 " beqzl %2, 1b \n"
414 " and %2, %0, %3 \n"
415 " .set mips0 \n"
416 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
417 : "r" (1UL << bit)
418 : "memory");
419 } else if (kernel_uses_llsc) {
420 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
421 unsigned long temp;
423 do {
424 __asm__ __volatile__(
425 " .set "MIPS_ISA_ARCH_LEVEL" \n"
426 " " __LL "%0, %1 # test_and_change_bit \n"
427 " xor %2, %0, %3 \n"
428 " " __SC "\t%2, %1 \n"
429 " .set mips0 \n"
430 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
431 : "r" (1UL << bit)
432 : "memory");
433 } while (unlikely(!res));
435 res = temp & (1UL << bit);
436 } else
437 res = __mips_test_and_change_bit(nr, addr);
439 smp_llsc_mb();
441 return res != 0;
444 #include <asm-generic/bitops/non-atomic.h>
447 * __clear_bit_unlock - Clears a bit in memory
448 * @nr: Bit to clear
449 * @addr: Address to start counting from
451 * __clear_bit() is non-atomic and implies release semantics before the memory
452 * operation. It can be used for an unlock if no other CPUs can concurrently
453 * modify other bits in the word.
455 static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
457 smp_mb__before_llsc();
458 __clear_bit(nr, addr);
459 nudge_writes();
463 * Return the bit position (0..63) of the most significant 1 bit in a word
464 * Returns -1 if no 1 bit exists
466 static inline unsigned long __fls(unsigned long word)
468 int num;
470 if (BITS_PER_LONG == 32 && !__builtin_constant_p(word) &&
471 __builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) {
472 __asm__(
473 " .set push \n"
474 " .set "MIPS_ISA_LEVEL" \n"
475 " clz %0, %1 \n"
476 " .set pop \n"
477 : "=r" (num)
478 : "r" (word));
480 return 31 - num;
483 if (BITS_PER_LONG == 64 && !__builtin_constant_p(word) &&
484 __builtin_constant_p(cpu_has_mips64) && cpu_has_mips64) {
485 __asm__(
486 " .set push \n"
487 " .set "MIPS_ISA_LEVEL" \n"
488 " dclz %0, %1 \n"
489 " .set pop \n"
490 : "=r" (num)
491 : "r" (word));
493 return 63 - num;
496 num = BITS_PER_LONG - 1;
498 #if BITS_PER_LONG == 64
499 if (!(word & (~0ul << 32))) {
500 num -= 32;
501 word <<= 32;
503 #endif
504 if (!(word & (~0ul << (BITS_PER_LONG-16)))) {
505 num -= 16;
506 word <<= 16;
508 if (!(word & (~0ul << (BITS_PER_LONG-8)))) {
509 num -= 8;
510 word <<= 8;
512 if (!(word & (~0ul << (BITS_PER_LONG-4)))) {
513 num -= 4;
514 word <<= 4;
516 if (!(word & (~0ul << (BITS_PER_LONG-2)))) {
517 num -= 2;
518 word <<= 2;
520 if (!(word & (~0ul << (BITS_PER_LONG-1))))
521 num -= 1;
522 return num;
526 * __ffs - find first bit in word.
527 * @word: The word to search
529 * Returns 0..SZLONG-1
530 * Undefined if no bit exists, so code should check against 0 first.
532 static inline unsigned long __ffs(unsigned long word)
534 return __fls(word & -word);
538 * fls - find last bit set.
539 * @word: The word to search
541 * This is defined the same way as ffs.
542 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
544 static inline int fls(int x)
546 int r;
548 if (!__builtin_constant_p(x) &&
549 __builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) {
550 __asm__(
551 " .set push \n"
552 " .set "MIPS_ISA_LEVEL" \n"
553 " clz %0, %1 \n"
554 " .set pop \n"
555 : "=r" (x)
556 : "r" (x));
558 return 32 - x;
561 r = 32;
562 if (!x)
563 return 0;
564 if (!(x & 0xffff0000u)) {
565 x <<= 16;
566 r -= 16;
568 if (!(x & 0xff000000u)) {
569 x <<= 8;
570 r -= 8;
572 if (!(x & 0xf0000000u)) {
573 x <<= 4;
574 r -= 4;
576 if (!(x & 0xc0000000u)) {
577 x <<= 2;
578 r -= 2;
580 if (!(x & 0x80000000u)) {
581 x <<= 1;
582 r -= 1;
584 return r;
587 #include <asm-generic/bitops/fls64.h>
590 * ffs - find first bit set.
591 * @word: The word to search
593 * This is defined the same way as
594 * the libc and compiler builtin ffs routines, therefore
595 * differs in spirit from the above ffz (man ffs).
597 static inline int ffs(int word)
599 if (!word)
600 return 0;
602 return fls(word & -word);
605 #include <asm-generic/bitops/ffz.h>
606 #include <asm-generic/bitops/find.h>
608 #ifdef __KERNEL__
610 #include <asm-generic/bitops/sched.h>
612 #include <asm/arch_hweight.h>
613 #include <asm-generic/bitops/const_hweight.h>
615 #include <asm-generic/bitops/le.h>
616 #include <asm-generic/bitops/ext2-atomic.h>
618 #endif /* __KERNEL__ */
620 #endif /* _ASM_BITOPS_H */