xref: /openbmc/linux/arch/ia64/include/asm/bitops.h (revision 588b48ca)
1 #ifndef _ASM_IA64_BITOPS_H
2 #define _ASM_IA64_BITOPS_H
3 
4 /*
5  * Copyright (C) 1998-2003 Hewlett-Packard Co
6  *	David Mosberger-Tang <davidm@hpl.hp.com>
7  *
8  * 02/06/02 find_next_bit() and find_first_bit() added from Erich Focht's ia64
9  * O(1) scheduler patch
10  */
11 
12 #ifndef _LINUX_BITOPS_H
13 #error only <linux/bitops.h> can be included directly
14 #endif
15 
16 #include <linux/compiler.h>
17 #include <linux/types.h>
18 #include <asm/intrinsics.h>
19 #include <asm/barrier.h>
20 
21 /**
22  * set_bit - Atomically set a bit in memory
23  * @nr: the bit to set
24  * @addr: the address to start counting from
25  *
26  * This function is atomic and may not be reordered.  See __set_bit()
27  * if you do not require the atomic guarantees.
28  * Note that @nr may be almost arbitrarily large; this function is not
29  * restricted to acting on a single-word quantity.
30  *
31  * The address must be (at least) "long" aligned.
32  * Note that there are driver (e.g., eepro100) which use these operations to
33  * operate on hw-defined data-structures, so we can't easily change these
34  * operations to force a bigger alignment.
35  *
36  * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
37  */
38 static __inline__ void
39 set_bit (int nr, volatile void *addr)
40 {
41 	__u32 bit, old, new;
42 	volatile __u32 *m;
43 	CMPXCHG_BUGCHECK_DECL
44 
45 	m = (volatile __u32 *) addr + (nr >> 5);
46 	bit = 1 << (nr & 31);
47 	do {
48 		CMPXCHG_BUGCHECK(m);
49 		old = *m;
50 		new = old | bit;
51 	} while (cmpxchg_acq(m, old, new) != old);
52 }
53 
54 /**
55  * __set_bit - Set a bit in memory
56  * @nr: the bit to set
57  * @addr: the address to start counting from
58  *
59  * Unlike set_bit(), this function is non-atomic and may be reordered.
60  * If it's called on the same region of memory simultaneously, the effect
61  * may be that only one operation succeeds.
62  */
63 static __inline__ void
64 __set_bit (int nr, volatile void *addr)
65 {
66 	*((__u32 *) addr + (nr >> 5)) |= (1 << (nr & 31));
67 }
68 
69 /**
70  * clear_bit - Clears a bit in memory
71  * @nr: Bit to clear
72  * @addr: Address to start counting from
73  *
74  * clear_bit() is atomic and may not be reordered.  However, it does
75  * not contain a memory barrier, so if it is used for locking purposes,
76  * you should call smp_mb__before_atomic() and/or smp_mb__after_atomic()
77  * in order to ensure changes are visible on other processors.
78  */
79 static __inline__ void
80 clear_bit (int nr, volatile void *addr)
81 {
82 	__u32 mask, old, new;
83 	volatile __u32 *m;
84 	CMPXCHG_BUGCHECK_DECL
85 
86 	m = (volatile __u32 *) addr + (nr >> 5);
87 	mask = ~(1 << (nr & 31));
88 	do {
89 		CMPXCHG_BUGCHECK(m);
90 		old = *m;
91 		new = old & mask;
92 	} while (cmpxchg_acq(m, old, new) != old);
93 }
94 
95 /**
96  * clear_bit_unlock - Clears a bit in memory with release
97  * @nr: Bit to clear
98  * @addr: Address to start counting from
99  *
100  * clear_bit_unlock() is atomic and may not be reordered.  It does
101  * contain a memory barrier suitable for unlock type operations.
102  */
103 static __inline__ void
104 clear_bit_unlock (int nr, volatile void *addr)
105 {
106 	__u32 mask, old, new;
107 	volatile __u32 *m;
108 	CMPXCHG_BUGCHECK_DECL
109 
110 	m = (volatile __u32 *) addr + (nr >> 5);
111 	mask = ~(1 << (nr & 31));
112 	do {
113 		CMPXCHG_BUGCHECK(m);
114 		old = *m;
115 		new = old & mask;
116 	} while (cmpxchg_rel(m, old, new) != old);
117 }
118 
119 /**
120  * __clear_bit_unlock - Non-atomically clears a bit in memory with release
121  * @nr: Bit to clear
122  * @addr: Address to start counting from
123  *
124  * Similarly to clear_bit_unlock, the implementation uses a store
125  * with release semantics. See also arch_spin_unlock().
126  */
127 static __inline__ void
128 __clear_bit_unlock(int nr, void *addr)
129 {
130 	__u32 * const m = (__u32 *) addr + (nr >> 5);
131 	__u32 const new = *m & ~(1 << (nr & 31));
132 
133 	ia64_st4_rel_nta(m, new);
134 }
135 
136 /**
137  * __clear_bit - Clears a bit in memory (non-atomic version)
138  * @nr: the bit to clear
139  * @addr: the address to start counting from
140  *
141  * Unlike clear_bit(), this function is non-atomic and may be reordered.
142  * If it's called on the same region of memory simultaneously, the effect
143  * may be that only one operation succeeds.
144  */
145 static __inline__ void
146 __clear_bit (int nr, volatile void *addr)
147 {
148 	*((__u32 *) addr + (nr >> 5)) &= ~(1 << (nr & 31));
149 }
150 
151 /**
152  * change_bit - Toggle a bit in memory
153  * @nr: Bit to toggle
154  * @addr: Address to start counting from
155  *
156  * change_bit() is atomic and may not be reordered.
157  * Note that @nr may be almost arbitrarily large; this function is not
158  * restricted to acting on a single-word quantity.
159  */
160 static __inline__ void
161 change_bit (int nr, volatile void *addr)
162 {
163 	__u32 bit, old, new;
164 	volatile __u32 *m;
165 	CMPXCHG_BUGCHECK_DECL
166 
167 	m = (volatile __u32 *) addr + (nr >> 5);
168 	bit = (1 << (nr & 31));
169 	do {
170 		CMPXCHG_BUGCHECK(m);
171 		old = *m;
172 		new = old ^ bit;
173 	} while (cmpxchg_acq(m, old, new) != old);
174 }
175 
176 /**
177  * __change_bit - Toggle a bit in memory
178  * @nr: the bit to toggle
179  * @addr: the address to start counting from
180  *
181  * Unlike change_bit(), this function is non-atomic and may be reordered.
182  * If it's called on the same region of memory simultaneously, the effect
183  * may be that only one operation succeeds.
184  */
185 static __inline__ void
186 __change_bit (int nr, volatile void *addr)
187 {
188 	*((__u32 *) addr + (nr >> 5)) ^= (1 << (nr & 31));
189 }
190 
191 /**
192  * test_and_set_bit - Set a bit and return its old value
193  * @nr: Bit to set
194  * @addr: Address to count from
195  *
196  * This operation is atomic and cannot be reordered.
197  * It also implies the acquisition side of the memory barrier.
198  */
199 static __inline__ int
200 test_and_set_bit (int nr, volatile void *addr)
201 {
202 	__u32 bit, old, new;
203 	volatile __u32 *m;
204 	CMPXCHG_BUGCHECK_DECL
205 
206 	m = (volatile __u32 *) addr + (nr >> 5);
207 	bit = 1 << (nr & 31);
208 	do {
209 		CMPXCHG_BUGCHECK(m);
210 		old = *m;
211 		new = old | bit;
212 	} while (cmpxchg_acq(m, old, new) != old);
213 	return (old & bit) != 0;
214 }
215 
216 /**
217  * test_and_set_bit_lock - Set a bit and return its old value for lock
218  * @nr: Bit to set
219  * @addr: Address to count from
220  *
221  * This is the same as test_and_set_bit on ia64
222  */
223 #define test_and_set_bit_lock test_and_set_bit
224 
225 /**
226  * __test_and_set_bit - Set a bit and return its old value
227  * @nr: Bit to set
228  * @addr: Address to count from
229  *
230  * This operation is non-atomic and can be reordered.
231  * If two examples of this operation race, one can appear to succeed
232  * but actually fail.  You must protect multiple accesses with a lock.
233  */
234 static __inline__ int
235 __test_and_set_bit (int nr, volatile void *addr)
236 {
237 	__u32 *p = (__u32 *) addr + (nr >> 5);
238 	__u32 m = 1 << (nr & 31);
239 	int oldbitset = (*p & m) != 0;
240 
241 	*p |= m;
242 	return oldbitset;
243 }
244 
245 /**
246  * test_and_clear_bit - Clear a bit and return its old value
247  * @nr: Bit to clear
248  * @addr: Address to count from
249  *
250  * This operation is atomic and cannot be reordered.
251  * It also implies the acquisition side of the memory barrier.
252  */
253 static __inline__ int
254 test_and_clear_bit (int nr, volatile void *addr)
255 {
256 	__u32 mask, old, new;
257 	volatile __u32 *m;
258 	CMPXCHG_BUGCHECK_DECL
259 
260 	m = (volatile __u32 *) addr + (nr >> 5);
261 	mask = ~(1 << (nr & 31));
262 	do {
263 		CMPXCHG_BUGCHECK(m);
264 		old = *m;
265 		new = old & mask;
266 	} while (cmpxchg_acq(m, old, new) != old);
267 	return (old & ~mask) != 0;
268 }
269 
270 /**
271  * __test_and_clear_bit - Clear a bit and return its old value
272  * @nr: Bit to clear
273  * @addr: Address to count from
274  *
275  * This operation is non-atomic and can be reordered.
276  * If two examples of this operation race, one can appear to succeed
277  * but actually fail.  You must protect multiple accesses with a lock.
278  */
279 static __inline__ int
280 __test_and_clear_bit(int nr, volatile void * addr)
281 {
282 	__u32 *p = (__u32 *) addr + (nr >> 5);
283 	__u32 m = 1 << (nr & 31);
284 	int oldbitset = (*p & m) != 0;
285 
286 	*p &= ~m;
287 	return oldbitset;
288 }
289 
290 /**
291  * test_and_change_bit - Change a bit and return its old value
292  * @nr: Bit to change
293  * @addr: Address to count from
294  *
295  * This operation is atomic and cannot be reordered.
296  * It also implies the acquisition side of the memory barrier.
297  */
298 static __inline__ int
299 test_and_change_bit (int nr, volatile void *addr)
300 {
301 	__u32 bit, old, new;
302 	volatile __u32 *m;
303 	CMPXCHG_BUGCHECK_DECL
304 
305 	m = (volatile __u32 *) addr + (nr >> 5);
306 	bit = (1 << (nr & 31));
307 	do {
308 		CMPXCHG_BUGCHECK(m);
309 		old = *m;
310 		new = old ^ bit;
311 	} while (cmpxchg_acq(m, old, new) != old);
312 	return (old & bit) != 0;
313 }
314 
315 /**
316  * __test_and_change_bit - Change a bit and return its old value
317  * @nr: Bit to change
318  * @addr: Address to count from
319  *
320  * This operation is non-atomic and can be reordered.
321  */
322 static __inline__ int
323 __test_and_change_bit (int nr, void *addr)
324 {
325 	__u32 old, bit = (1 << (nr & 31));
326 	__u32 *m = (__u32 *) addr + (nr >> 5);
327 
328 	old = *m;
329 	*m = old ^ bit;
330 	return (old & bit) != 0;
331 }
332 
333 static __inline__ int
334 test_bit (int nr, const volatile void *addr)
335 {
336 	return 1 & (((const volatile __u32 *) addr)[nr >> 5] >> (nr & 31));
337 }
338 
339 /**
340  * ffz - find the first zero bit in a long word
341  * @x: The long word to find the bit in
342  *
343  * Returns the bit-number (0..63) of the first (least significant) zero bit.
344  * Undefined if no zero exists, so code should check against ~0UL first...
345  */
346 static inline unsigned long
347 ffz (unsigned long x)
348 {
349 	unsigned long result;
350 
351 	result = ia64_popcnt(x & (~x - 1));
352 	return result;
353 }
354 
355 /**
356  * __ffs - find first bit in word.
357  * @x: The word to search
358  *
359  * Undefined if no bit exists, so code should check against 0 first.
360  */
361 static __inline__ unsigned long
362 __ffs (unsigned long x)
363 {
364 	unsigned long result;
365 
366 	result = ia64_popcnt((x-1) & ~x);
367 	return result;
368 }
369 
370 #ifdef __KERNEL__
371 
372 /*
373  * Return bit number of last (most-significant) bit set.  Undefined
374  * for x==0.  Bits are numbered from 0..63 (e.g., ia64_fls(9) == 3).
375  */
376 static inline unsigned long
377 ia64_fls (unsigned long x)
378 {
379 	long double d = x;
380 	long exp;
381 
382 	exp = ia64_getf_exp(d);
383 	return exp - 0xffff;
384 }
385 
386 /*
387  * Find the last (most significant) bit set.  Returns 0 for x==0 and
388  * bits are numbered from 1..32 (e.g., fls(9) == 4).
389  */
390 static inline int
391 fls (int t)
392 {
393 	unsigned long x = t & 0xffffffffu;
394 
395 	if (!x)
396 		return 0;
397 	x |= x >> 1;
398 	x |= x >> 2;
399 	x |= x >> 4;
400 	x |= x >> 8;
401 	x |= x >> 16;
402 	return ia64_popcnt(x);
403 }
404 
405 /*
406  * Find the last (most significant) bit set.  Undefined for x==0.
407  * Bits are numbered from 0..63 (e.g., __fls(9) == 3).
408  */
409 static inline unsigned long
410 __fls (unsigned long x)
411 {
412 	x |= x >> 1;
413 	x |= x >> 2;
414 	x |= x >> 4;
415 	x |= x >> 8;
416 	x |= x >> 16;
417 	x |= x >> 32;
418 	return ia64_popcnt(x) - 1;
419 }
420 
421 #include <asm-generic/bitops/fls64.h>
422 
423 #include <asm-generic/bitops/builtin-ffs.h>
424 
425 /*
426  * hweightN: returns the hamming weight (i.e. the number
427  * of bits set) of a N-bit word
428  */
429 static __inline__ unsigned long __arch_hweight64(unsigned long x)
430 {
431 	unsigned long result;
432 	result = ia64_popcnt(x);
433 	return result;
434 }
435 
436 #define __arch_hweight32(x) ((unsigned int) __arch_hweight64((x) & 0xfffffffful))
437 #define __arch_hweight16(x) ((unsigned int) __arch_hweight64((x) & 0xfffful))
438 #define __arch_hweight8(x)  ((unsigned int) __arch_hweight64((x) & 0xfful))
439 
440 #include <asm-generic/bitops/const_hweight.h>
441 
442 #endif /* __KERNEL__ */
443 
444 #include <asm-generic/bitops/find.h>
445 
446 #ifdef __KERNEL__
447 
448 #include <asm-generic/bitops/le.h>
449 
450 #include <asm-generic/bitops/ext2-atomic-setbit.h>
451 
452 #include <asm-generic/bitops/sched.h>
453 
454 #endif /* __KERNEL__ */
455 
456 #endif /* _ASM_IA64_BITOPS_H */
457