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.
5 *
6 * Copyright (c) 1994, 95, 96, 97, 98, 99, 2000 Ralf Baechle
7 * Copyright (c) 1999, 2000 Silicon Graphics, Inc.
8 */
9 #ifndef _ASM_BITOPS_H
10 #define _ASM_BITOPS_H
11
12 #include <linux/types.h>
13 #include <linux/byteorder/swab.h> /* sigh ... */
14
15 #ifndef __KERNEL__
16 #error "Don't do this, sucker ..."
17 #endif
18
19 #include <asm/system.h>
20 #include <asm/sgidefs.h>
21 #include <asm/mipsregs.h>
22
23 /*
24 * clear_bit() doesn't provide any barrier for the compiler.
25 */
26 #define smp_mb__before_clear_bit() barrier()
27 #define smp_mb__after_clear_bit() barrier()
28
29 /*
30 * These functions for MIPS ISA > 1 are interrupt and SMP proof and
31 * interrupt friendly
32 */
33
34 extern __inline__ void
35 set_bit(unsigned long nr, volatile void *addr)
36 {
37 unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
38 unsigned long temp;
39
40 __asm__ __volatile__(
41 "1:\tlld\t%0, %1\t\t# set_bit\n\t"
42 "or\t%0, %2\n\t"
43 "scd\t%0, %1\n\t"
44 "beqz\t%0, 1b"
45 : "=&r" (temp), "=m" (*m)
46 : "ir" (1UL << (nr & 0x3f)), "m" (*m)
47 : "memory");
48 }
49
50 /* WARNING: non atomic and it can be reordered! */
51 extern __inline__ void __set_bit(int nr, volatile void * addr)
52 {
53 unsigned long * m = ((unsigned long *) addr) + (nr >> 6);
54
55 *m |= 1UL << (nr & 0x3f);
56 }
57
58 extern __inline__ void
59 clear_bit(unsigned long nr, volatile void *addr)
60 {
61 unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
62 unsigned long temp;
63
64 __asm__ __volatile__(
65 "1:\tlld\t%0, %1\t\t# clear_bit\n\t"
66 "and\t%0, %2\n\t"
67 "scd\t%0, %1\n\t"
68 "beqz\t%0, 1b\n\t"
69 : "=&r" (temp), "=m" (*m)
70 : "ir" (~(1UL << (nr & 0x3f))), "m" (*m));
71 }
72
73
74 extern __inline__ void
75 change_bit(unsigned long nr, volatile void *addr)
76 {
77 unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
78 unsigned long temp;
79
80 __asm__ __volatile__(
81 "1:\tlld\t%0, %1\t\t# change_bit\n\t"
82 "xor\t%0, %2\n\t"
83 "scd\t%0, %1\n\t"
84 "beqz\t%0, 1b"
85 :"=&r" (temp), "=m" (*m)
86 :"ir" (1UL << (nr & 0x3f)), "m" (*m));
87 }
88
89 extern __inline__ unsigned long
90 test_and_set_bit(unsigned long nr, volatile void *addr)
91 {
92 unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
93 unsigned long temp, res;
94
95 __asm__ __volatile__(
96 ".set\tnoreorder\t\t# test_and_set_bit\n"
97 "1:\tlld\t%0, %1\n\t"
98 "or\t%2, %0, %3\n\t"
99 "scd\t%2, %1\n\t"
100 "beqz\t%2, 1b\n\t"
101 " and\t%2, %0, %3\n\t"
102 ".set\treorder"
103 : "=&r" (temp), "=m" (*m), "=&r" (res)
104 : "r" (1UL << (nr & 0x3f)), "m" (*m)
105 : "memory");
106
107 return res != 0;
108 }
109
110 extern __inline__ int __test_and_set_bit(int nr, volatile void * addr)
111 {
112 int mask, retval;
113 volatile long *a = addr;
114
115 a += nr >> 6;
116 mask = 1 << (nr & 0x3f);
117 retval = (mask & *a) != 0;
118 *a |= mask;
119
120 return retval;
121 }
122
123 extern __inline__ unsigned long
124 test_and_clear_bit(unsigned long nr, volatile void *addr)
125 {
126 unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
127 unsigned long temp, res;
128
129 __asm__ __volatile__(
130 ".set\tnoreorder\t\t# test_and_clear_bit\n"
131 "1:\tlld\t%0, %1\n\t"
132 "or\t%2, %0, %3\n\t"
133 "xor\t%2, %3\n\t"
134 "scd\t%2, %1\n\t"
135 "beqz\t%2, 1b\n\t"
136 " and\t%2, %0, %3\n\t"
137 ".set\treorder"
138 : "=&r" (temp), "=m" (*m), "=&r" (res)
139 : "r" (1UL << (nr & 0x3f)), "m" (*m)
140 : "memory");
141
142 return res != 0;
143 }
144
145 extern __inline__ int __test_and_clear_bit(int nr, volatile void * addr)
146 {
147 int mask, retval;
148 volatile long *a = addr;
149
150 a += nr >> 6;
151 mask = 1 << (nr & 0x3f);
152 retval = (mask & *a) != 0;
153 *a &= ~mask;
154
155 return retval;
156 }
157
158 extern __inline__ unsigned long
159 test_and_change_bit(unsigned long nr, volatile void *addr)
160 {
161 unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
162 unsigned long temp, res;
163
164 __asm__ __volatile__(
165 ".set\tnoreorder\t\t# test_and_change_bit\n"
166 "1:\tlld\t%0, %1\n\t"
167 "xor\t%2, %0, %3\n\t"
168 "scd\t%2, %1\n\t"
169 "beqz\t%2, 1b\n\t"
170 " and\t%2, %0, %3\n\t"
171 ".set\treorder"
172 : "=&r" (temp), "=m" (*m), "=&r" (res)
173 : "r" (1UL << (nr & 0x3f)), "m" (*m)
174 : "memory");
175
176 return res != 0;
177 }
178
179 extern __inline__ unsigned long
180 test_bit(int nr, volatile void * addr)
181 {
182 return 1UL & (((const long *) addr)[nr >> 6] >> (nr & 0x3f));
183 }
184
185 #ifndef __MIPSEB__
186
187 /* Little endian versions. */
188
189 extern __inline__ int
190 find_first_zero_bit (void *addr, unsigned size)
191 {
192 unsigned long dummy;
193 int res;
194
195 if (!size)
196 return 0;
197
198 __asm__ (".set\tnoreorder\n\t"
199 ".set\tnoat\n"
200 "1:\tsubu\t$1,%6,%0\n\t"
201 "blez\t$1,2f\n\t"
202 "lw\t$1,(%5)\n\t"
203 "addiu\t%5,4\n\t"
204 #if (_MIPS_ISA == _MIPS_ISA_MIPS2) || (_MIPS_ISA == _MIPS_ISA_MIPS3) || \
205 (_MIPS_ISA == _MIPS_ISA_MIPS4) || (_MIPS_ISA == _MIPS_ISA_MIPS5)
206 "beql\t%1,$1,1b\n\t"
207 "addiu\t%0,32\n\t"
208 #else
209 "addiu\t%0,32\n\t"
210 "beq\t%1,$1,1b\n\t"
211 "nop\n\t"
212 "subu\t%0,32\n\t"
213 #endif
214 "li\t%1,1\n"
215 "1:\tand\t%2,$1,%1\n\t"
216 "beqz\t%2,2f\n\t"
217 "sll\t%1,%1,1\n\t"
218 "bnez\t%1,1b\n\t"
219 "add\t%0,%0,1\n\t"
220 ".set\tat\n\t"
221 ".set\treorder\n"
222 "2:"
223 : "=r" (res), "=r" (dummy), "=r" (addr)
224 : "" ((signed int) 0), "1" ((unsigned int) 0xffffffff),
225 "2" (addr), "r" (size)
226 : "$1");
227
228 return res;
229 }
230
231 extern __inline__ int
232 find_next_zero_bit (void * addr, int size, int offset)
233 {
234 unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
235 int set = 0, bit = offset & 31, res;
236 unsigned long dummy;
237
238 if (bit) {
239 /*
240 * Look for zero in first byte
241 */
242 __asm__(".set\tnoreorder\n\t"
243 ".set\tnoat\n"
244 "1:\tand\t$1,%4,%1\n\t"
245 "beqz\t$1,1f\n\t"
246 "sll\t%1,%1,1\n\t"
247 "bnez\t%1,1b\n\t"
248 "addiu\t%0,1\n\t"
249 ".set\tat\n\t"
250 ".set\treorder\n"
251 "1:"
252 : "=r" (set), "=r" (dummy)
253 : "" (0), "1" (1 << bit), "r" (*p)
254 : "$1");
255 if (set < (32 - bit))
256 return set + offset;
257 set = 32 - bit;
258 p++;
259 }
260 /*
261 * No zero yet, search remaining full bytes for a zero
262 */
263 res = find_first_zero_bit(p, size - 32 * (p - (unsigned int *) addr));
264 return offset + set + res;
265 }
266
267 #endif /* !(__MIPSEB__) */
268
269 /*
270 * ffz = Find First Zero in word. Undefined if no zero exists,
271 * so code should check against ~0UL first..
272 */
273 extern __inline__ unsigned long ffz(unsigned long word)
274 {
275 unsigned long k;
276
277 word = ~word;
278 k = 63;
279 if (word & 0x00000000ffffffffUL) { k -= 32; word <<= 32; }
280 if (word & 0x0000ffff00000000UL) { k -= 16; word <<= 16; }
281 if (word & 0x00ff000000000000UL) { k -= 8; word <<= 8; }
282 if (word & 0x0f00000000000000UL) { k -= 4; word <<= 4; }
283 if (word & 0x3000000000000000UL) { k -= 2; word <<= 2; }
284 if (word & 0x4000000000000000UL) { k -= 1; }
285
286 return k;
287 }
288
289 #ifdef __KERNEL__
290
291 /*
292 * ffs: find first bit set. This is defined the same way as
293 * the libc and compiler builtin ffs routines, therefore
294 * differs in spirit from the above ffz (man ffs).
295 */
296
297 #define ffs(x) generic_ffs(x)
298
299 /*
300 * hweightN: returns the hamming weight (i.e. the number
301 * of bits set) of a N-bit word
302 */
303
304 #define hweight32(x) generic_hweight32(x)
305 #define hweight16(x) generic_hweight16(x)
306 #define hweight8(x) generic_hweight8(x)
307
308 #endif /* __KERNEL__ */
309
310 #ifdef __MIPSEB__
311
312 /*
313 * find_next_zero_bit() finds the first zero bit in a bit string of length
314 * 'size' bits, starting the search at bit 'offset'. This is largely based
315 * on Linus's ALPHA routines, which are pretty portable BTW.
316 */
317
318 extern __inline__ unsigned long
319 find_next_zero_bit(void *addr, unsigned long size, unsigned long offset)
320 {
321 unsigned long *p = ((unsigned long *) addr) + (offset >> 6);
322 unsigned long result = offset & ~63UL;
323 unsigned long tmp;
324
325 if (offset >= size)
326 return size;
327 size -= result;
328 offset &= 63UL;
329 if (offset) {
330 tmp = *(p++);
331 tmp |= ~0UL >> (64-offset);
332 if (size < 64)
333 goto found_first;
334 if (~tmp)
335 goto found_middle;
336 size -= 64;
337 result += 64;
338 }
339 while (size & ~63UL) {
340 if (~(tmp = *(p++)))
341 goto found_middle;
342 result += 64;
343 size -= 64;
344 }
345 if (!size)
346 return result;
347 tmp = *p;
348
349 found_first:
350 tmp |= ~0UL << size;
351 found_middle:
352 return result + ffz(tmp);
353 }
354
355 #define find_first_zero_bit(addr, size) \
356 find_next_zero_bit((addr), (size), 0)
357
358 #endif /* (__MIPSEB__) */
359
360 #ifdef __KERNEL__
361
362 /* Now for the ext2 filesystem bit operations and helper routines. */
363
364 #ifdef __MIPSEB__
365
366 extern inline int
367 ext2_set_bit(int nr,void * addr)
368 {
369 int mask, retval, flags;
370 unsigned char *ADDR = (unsigned char *) addr;
371
372 ADDR += nr >> 3;
373 mask = 1 << (nr & 0x07);
374 save_and_cli(flags);
375 retval = (mask & *ADDR) != 0;
376 *ADDR |= mask;
377 restore_flags(flags);
378 return retval;
379 }
380
381 extern inline int
382 ext2_clear_bit(int nr, void * addr)
383 {
384 int mask, retval, flags;
385 unsigned char *ADDR = (unsigned char *) addr;
386
387 ADDR += nr >> 3;
388 mask = 1 << (nr & 0x07);
389 save_and_cli(flags);
390 retval = (mask & *ADDR) != 0;
391 *ADDR &= ~mask;
392 restore_flags(flags);
393 return retval;
394 }
395
396 extern inline int
397 ext2_test_bit(int nr, const void * addr)
398 {
399 int mask;
400 const unsigned char *ADDR = (const unsigned char *) addr;
401
402 ADDR += nr >> 3;
403 mask = 1 << (nr & 0x07);
404 return ((mask & *ADDR) != 0);
405 }
406
407 #define ext2_find_first_zero_bit(addr, size) \
408 ext2_find_next_zero_bit((addr), (size), 0)
409
410 extern inline unsigned int
411 ext2_find_next_zero_bit(void *addr, unsigned long size, unsigned long offset)
412 {
413 unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
414 unsigned int result = offset & ~31UL;
415 unsigned int tmp;
416
417 if (offset >= size)
418 return size;
419 size -= result;
420 offset &= 31UL;
421 if(offset) {
422 /* We hold the little endian value in tmp, but then the
423 * shift is illegal. So we could keep a big endian value
424 * in tmp, like this:
425 *
426 * tmp = __swab32(*(p++));
427 * tmp |= ~0UL >> (32-offset);
428 *
429 * but this would decrease preformance, so we change the
430 * shift:
431 */
432 tmp = *(p++);
433 tmp |= __swab32(~0UL >> (32-offset));
434 if(size < 32)
435 goto found_first;
436 if(~tmp)
437 goto found_middle;
438 size -= 32;
439 result += 32;
440 }
441 while(size & ~31UL) {
442 if(~(tmp = *(p++)))
443 goto found_middle;
444 result += 32;
445 size -= 32;
446 }
447 if(!size)
448 return result;
449 tmp = *p;
450
451 found_first:
452 /* tmp is little endian, so we would have to swab the shift,
453 * see above. But then we have to swab tmp below for ffz, so
454 * we might as well do this here.
455 */
456 return result + ffz(__swab32(tmp) | (~0UL << size));
457 found_middle:
458 return result + ffz(__swab32(tmp));
459 }
460 #else /* !(__MIPSEB__) */
461
462 /* Native ext2 byte ordering, just collapse using defines. */
463 #define ext2_set_bit(nr, addr) test_and_set_bit((nr), (addr))
464 #define ext2_clear_bit(nr, addr) test_and_clear_bit((nr), (addr))
465 #define ext2_test_bit(nr, addr) test_bit((nr), (addr))
466 #define ext2_find_first_zero_bit(addr, size) find_first_zero_bit((addr), (size))
467 #define ext2_find_next_zero_bit(addr, size, offset) \
468 find_next_zero_bit((addr), (size), (offset))
469
470 #endif /* !(__MIPSEB__) */
471
472 /*
473 * Bitmap functions for the minix filesystem.
474 * FIXME: These assume that Minix uses the native byte/bitorder.
475 * This limits the Minix filesystem's value for data exchange very much.
476 */
477 #define minix_test_and_set_bit(nr,addr) test_and_set_bit(nr,addr)
478 #define minix_set_bit(nr,addr) set_bit(nr,addr)
479 #define minix_test_and_clear_bit(nr,addr) test_and_clear_bit(nr,addr)
480 #define minix_test_bit(nr,addr) test_bit(nr,addr)
481 #define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size)
482
483 #endif /* __KERNEL__ */
484
485 #endif /* _ASM_BITOPS_H */
486
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