xref: /openbmc/linux/arch/alpha/include/asm/bitops.h (revision ecba1060)
1 #ifndef _ALPHA_BITOPS_H
2 #define _ALPHA_BITOPS_H
3 
4 #ifndef _LINUX_BITOPS_H
5 #error only <linux/bitops.h> can be included directly
6 #endif
7 
8 #include <asm/compiler.h>
9 #include <asm/barrier.h>
10 
11 /*
12  * Copyright 1994, Linus Torvalds.
13  */
14 
15 /*
16  * These have to be done with inline assembly: that way the bit-setting
17  * is guaranteed to be atomic. All bit operations return 0 if the bit
18  * was cleared before the operation and != 0 if it was not.
19  *
20  * To get proper branch prediction for the main line, we must branch
21  * forward to code at the end of this object's .text section, then
22  * branch back to restart the operation.
23  *
24  * bit 0 is the LSB of addr; bit 64 is the LSB of (addr+1).
25  */
26 
27 static inline void
28 set_bit(unsigned long nr, volatile void * addr)
29 {
30 	unsigned long temp;
31 	int *m = ((int *) addr) + (nr >> 5);
32 
33 	__asm__ __volatile__(
34 	"1:	ldl_l %0,%3\n"
35 	"	bis %0,%2,%0\n"
36 	"	stl_c %0,%1\n"
37 	"	beq %0,2f\n"
38 	".subsection 2\n"
39 	"2:	br 1b\n"
40 	".previous"
41 	:"=&r" (temp), "=m" (*m)
42 	:"Ir" (1UL << (nr & 31)), "m" (*m));
43 }
44 
45 /*
46  * WARNING: non atomic version.
47  */
48 static inline void
49 __set_bit(unsigned long nr, volatile void * addr)
50 {
51 	int *m = ((int *) addr) + (nr >> 5);
52 
53 	*m |= 1 << (nr & 31);
54 }
55 
56 #define smp_mb__before_clear_bit()	smp_mb()
57 #define smp_mb__after_clear_bit()	smp_mb()
58 
59 static inline void
60 clear_bit(unsigned long nr, volatile void * addr)
61 {
62 	unsigned long temp;
63 	int *m = ((int *) addr) + (nr >> 5);
64 
65 	__asm__ __volatile__(
66 	"1:	ldl_l %0,%3\n"
67 	"	bic %0,%2,%0\n"
68 	"	stl_c %0,%1\n"
69 	"	beq %0,2f\n"
70 	".subsection 2\n"
71 	"2:	br 1b\n"
72 	".previous"
73 	:"=&r" (temp), "=m" (*m)
74 	:"Ir" (1UL << (nr & 31)), "m" (*m));
75 }
76 
77 static inline void
78 clear_bit_unlock(unsigned long nr, volatile void * addr)
79 {
80 	smp_mb();
81 	clear_bit(nr, addr);
82 }
83 
84 /*
85  * WARNING: non atomic version.
86  */
87 static __inline__ void
88 __clear_bit(unsigned long nr, volatile void * addr)
89 {
90 	int *m = ((int *) addr) + (nr >> 5);
91 
92 	*m &= ~(1 << (nr & 31));
93 }
94 
95 static inline void
96 __clear_bit_unlock(unsigned long nr, volatile void * addr)
97 {
98 	smp_mb();
99 	__clear_bit(nr, addr);
100 }
101 
102 static inline void
103 change_bit(unsigned long nr, volatile void * addr)
104 {
105 	unsigned long temp;
106 	int *m = ((int *) addr) + (nr >> 5);
107 
108 	__asm__ __volatile__(
109 	"1:	ldl_l %0,%3\n"
110 	"	xor %0,%2,%0\n"
111 	"	stl_c %0,%1\n"
112 	"	beq %0,2f\n"
113 	".subsection 2\n"
114 	"2:	br 1b\n"
115 	".previous"
116 	:"=&r" (temp), "=m" (*m)
117 	:"Ir" (1UL << (nr & 31)), "m" (*m));
118 }
119 
120 /*
121  * WARNING: non atomic version.
122  */
123 static __inline__ void
124 __change_bit(unsigned long nr, volatile void * addr)
125 {
126 	int *m = ((int *) addr) + (nr >> 5);
127 
128 	*m ^= 1 << (nr & 31);
129 }
130 
131 static inline int
132 test_and_set_bit(unsigned long nr, volatile void *addr)
133 {
134 	unsigned long oldbit;
135 	unsigned long temp;
136 	int *m = ((int *) addr) + (nr >> 5);
137 
138 	__asm__ __volatile__(
139 #ifdef CONFIG_SMP
140 	"	mb\n"
141 #endif
142 	"1:	ldl_l %0,%4\n"
143 	"	and %0,%3,%2\n"
144 	"	bne %2,2f\n"
145 	"	xor %0,%3,%0\n"
146 	"	stl_c %0,%1\n"
147 	"	beq %0,3f\n"
148 	"2:\n"
149 #ifdef CONFIG_SMP
150 	"	mb\n"
151 #endif
152 	".subsection 2\n"
153 	"3:	br 1b\n"
154 	".previous"
155 	:"=&r" (temp), "=m" (*m), "=&r" (oldbit)
156 	:"Ir" (1UL << (nr & 31)), "m" (*m) : "memory");
157 
158 	return oldbit != 0;
159 }
160 
161 static inline int
162 test_and_set_bit_lock(unsigned long nr, volatile void *addr)
163 {
164 	unsigned long oldbit;
165 	unsigned long temp;
166 	int *m = ((int *) addr) + (nr >> 5);
167 
168 	__asm__ __volatile__(
169 	"1:	ldl_l %0,%4\n"
170 	"	and %0,%3,%2\n"
171 	"	bne %2,2f\n"
172 	"	xor %0,%3,%0\n"
173 	"	stl_c %0,%1\n"
174 	"	beq %0,3f\n"
175 	"2:\n"
176 #ifdef CONFIG_SMP
177 	"	mb\n"
178 #endif
179 	".subsection 2\n"
180 	"3:	br 1b\n"
181 	".previous"
182 	:"=&r" (temp), "=m" (*m), "=&r" (oldbit)
183 	:"Ir" (1UL << (nr & 31)), "m" (*m) : "memory");
184 
185 	return oldbit != 0;
186 }
187 
188 /*
189  * WARNING: non atomic version.
190  */
191 static inline int
192 __test_and_set_bit(unsigned long nr, volatile void * addr)
193 {
194 	unsigned long mask = 1 << (nr & 0x1f);
195 	int *m = ((int *) addr) + (nr >> 5);
196 	int old = *m;
197 
198 	*m = old | mask;
199 	return (old & mask) != 0;
200 }
201 
202 static inline int
203 test_and_clear_bit(unsigned long nr, volatile void * addr)
204 {
205 	unsigned long oldbit;
206 	unsigned long temp;
207 	int *m = ((int *) addr) + (nr >> 5);
208 
209 	__asm__ __volatile__(
210 #ifdef CONFIG_SMP
211 	"	mb\n"
212 #endif
213 	"1:	ldl_l %0,%4\n"
214 	"	and %0,%3,%2\n"
215 	"	beq %2,2f\n"
216 	"	xor %0,%3,%0\n"
217 	"	stl_c %0,%1\n"
218 	"	beq %0,3f\n"
219 	"2:\n"
220 #ifdef CONFIG_SMP
221 	"	mb\n"
222 #endif
223 	".subsection 2\n"
224 	"3:	br 1b\n"
225 	".previous"
226 	:"=&r" (temp), "=m" (*m), "=&r" (oldbit)
227 	:"Ir" (1UL << (nr & 31)), "m" (*m) : "memory");
228 
229 	return oldbit != 0;
230 }
231 
232 /*
233  * WARNING: non atomic version.
234  */
235 static inline int
236 __test_and_clear_bit(unsigned long nr, volatile void * addr)
237 {
238 	unsigned long mask = 1 << (nr & 0x1f);
239 	int *m = ((int *) addr) + (nr >> 5);
240 	int old = *m;
241 
242 	*m = old & ~mask;
243 	return (old & mask) != 0;
244 }
245 
246 static inline int
247 test_and_change_bit(unsigned long nr, volatile void * addr)
248 {
249 	unsigned long oldbit;
250 	unsigned long temp;
251 	int *m = ((int *) addr) + (nr >> 5);
252 
253 	__asm__ __volatile__(
254 #ifdef CONFIG_SMP
255 	"	mb\n"
256 #endif
257 	"1:	ldl_l %0,%4\n"
258 	"	and %0,%3,%2\n"
259 	"	xor %0,%3,%0\n"
260 	"	stl_c %0,%1\n"
261 	"	beq %0,3f\n"
262 #ifdef CONFIG_SMP
263 	"	mb\n"
264 #endif
265 	".subsection 2\n"
266 	"3:	br 1b\n"
267 	".previous"
268 	:"=&r" (temp), "=m" (*m), "=&r" (oldbit)
269 	:"Ir" (1UL << (nr & 31)), "m" (*m) : "memory");
270 
271 	return oldbit != 0;
272 }
273 
274 /*
275  * WARNING: non atomic version.
276  */
277 static __inline__ int
278 __test_and_change_bit(unsigned long nr, volatile void * addr)
279 {
280 	unsigned long mask = 1 << (nr & 0x1f);
281 	int *m = ((int *) addr) + (nr >> 5);
282 	int old = *m;
283 
284 	*m = old ^ mask;
285 	return (old & mask) != 0;
286 }
287 
288 static inline int
289 test_bit(int nr, const volatile void * addr)
290 {
291 	return (1UL & (((const int *) addr)[nr >> 5] >> (nr & 31))) != 0UL;
292 }
293 
294 /*
295  * ffz = Find First Zero in word. Undefined if no zero exists,
296  * so code should check against ~0UL first..
297  *
298  * Do a binary search on the bits.  Due to the nature of large
299  * constants on the alpha, it is worthwhile to split the search.
300  */
301 static inline unsigned long ffz_b(unsigned long x)
302 {
303 	unsigned long sum, x1, x2, x4;
304 
305 	x = ~x & -~x;		/* set first 0 bit, clear others */
306 	x1 = x & 0xAA;
307 	x2 = x & 0xCC;
308 	x4 = x & 0xF0;
309 	sum = x2 ? 2 : 0;
310 	sum += (x4 != 0) * 4;
311 	sum += (x1 != 0);
312 
313 	return sum;
314 }
315 
316 static inline unsigned long ffz(unsigned long word)
317 {
318 #if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
319 	/* Whee.  EV67 can calculate it directly.  */
320 	return __kernel_cttz(~word);
321 #else
322 	unsigned long bits, qofs, bofs;
323 
324 	bits = __kernel_cmpbge(word, ~0UL);
325 	qofs = ffz_b(bits);
326 	bits = __kernel_extbl(word, qofs);
327 	bofs = ffz_b(bits);
328 
329 	return qofs*8 + bofs;
330 #endif
331 }
332 
333 /*
334  * __ffs = Find First set bit in word.  Undefined if no set bit exists.
335  */
336 static inline unsigned long __ffs(unsigned long word)
337 {
338 #if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
339 	/* Whee.  EV67 can calculate it directly.  */
340 	return __kernel_cttz(word);
341 #else
342 	unsigned long bits, qofs, bofs;
343 
344 	bits = __kernel_cmpbge(0, word);
345 	qofs = ffz_b(bits);
346 	bits = __kernel_extbl(word, qofs);
347 	bofs = ffz_b(~bits);
348 
349 	return qofs*8 + bofs;
350 #endif
351 }
352 
353 #ifdef __KERNEL__
354 
355 /*
356  * ffs: find first bit set. This is defined the same way as
357  * the libc and compiler builtin ffs routines, therefore
358  * differs in spirit from the above __ffs.
359  */
360 
361 static inline int ffs(int word)
362 {
363 	int result = __ffs(word) + 1;
364 	return word ? result : 0;
365 }
366 
367 /*
368  * fls: find last bit set.
369  */
370 #if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
371 static inline int fls64(unsigned long word)
372 {
373 	return 64 - __kernel_ctlz(word);
374 }
375 #else
376 extern const unsigned char __flsm1_tab[256];
377 
378 static inline int fls64(unsigned long x)
379 {
380 	unsigned long t, a, r;
381 
382 	t = __kernel_cmpbge (x, 0x0101010101010101UL);
383 	a = __flsm1_tab[t];
384 	t = __kernel_extbl (x, a);
385 	r = a*8 + __flsm1_tab[t] + (x != 0);
386 
387 	return r;
388 }
389 #endif
390 
391 static inline unsigned long __fls(unsigned long x)
392 {
393 	return fls64(x) - 1;
394 }
395 
396 static inline int fls(int x)
397 {
398 	return fls64((unsigned int) x);
399 }
400 
401 /*
402  * hweightN: returns the hamming weight (i.e. the number
403  * of bits set) of a N-bit word
404  */
405 
406 #if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
407 /* Whee.  EV67 can calculate it directly.  */
408 static inline unsigned long hweight64(unsigned long w)
409 {
410 	return __kernel_ctpop(w);
411 }
412 
413 static inline unsigned int hweight32(unsigned int w)
414 {
415 	return hweight64(w);
416 }
417 
418 static inline unsigned int hweight16(unsigned int w)
419 {
420 	return hweight64(w & 0xffff);
421 }
422 
423 static inline unsigned int hweight8(unsigned int w)
424 {
425 	return hweight64(w & 0xff);
426 }
427 #else
428 #include <asm-generic/bitops/hweight.h>
429 #endif
430 
431 #endif /* __KERNEL__ */
432 
433 #include <asm-generic/bitops/find.h>
434 
435 #ifdef __KERNEL__
436 
437 /*
438  * Every architecture must define this function. It's the fastest
439  * way of searching a 140-bit bitmap where the first 100 bits are
440  * unlikely to be set. It's guaranteed that at least one of the 140
441  * bits is set.
442  */
443 static inline unsigned long
444 sched_find_first_bit(unsigned long b[3])
445 {
446 	unsigned long b0 = b[0], b1 = b[1], b2 = b[2];
447 	unsigned long ofs;
448 
449 	ofs = (b1 ? 64 : 128);
450 	b1 = (b1 ? b1 : b2);
451 	ofs = (b0 ? 0 : ofs);
452 	b0 = (b0 ? b0 : b1);
453 
454 	return __ffs(b0) + ofs;
455 }
456 
457 #include <asm-generic/bitops/ext2-non-atomic.h>
458 
459 #define ext2_set_bit_atomic(l,n,a)   test_and_set_bit(n,a)
460 #define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a)
461 
462 #include <asm-generic/bitops/minix.h>
463 
464 #endif /* __KERNEL__ */
465 
466 #endif /* _ALPHA_BITOPS_H */
467