x86/efi: Enforce CONFIG_RELOCATABLE for EFI boot stub
[linux/fpc-iii.git] / arch / ia64 / include / asm / bitops.h
blobc27eccd333495af692571cdca5152bfde7eb8e2f
1 #ifndef _ASM_IA64_BITOPS_H
2 #define _ASM_IA64_BITOPS_H
4 /*
5 * Copyright (C) 1998-2003 Hewlett-Packard Co
6 * David Mosberger-Tang <davidm@hpl.hp.com>
8 * 02/06/02 find_next_bit() and find_first_bit() added from Erich Focht's ia64
9 * O(1) scheduler patch
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/intrinsics.h>
20 /**
21 * set_bit - Atomically set a bit in memory
22 * @nr: the bit to set
23 * @addr: the address to start counting from
25 * This function is atomic and may not be reordered. See __set_bit()
26 * if you do not require the atomic guarantees.
27 * Note that @nr may be almost arbitrarily large; this function is not
28 * restricted to acting on a single-word quantity.
30 * The address must be (at least) "long" aligned.
31 * Note that there are driver (e.g., eepro100) which use these operations to
32 * operate on hw-defined data-structures, so we can't easily change these
33 * operations to force a bigger alignment.
35 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
37 static __inline__ void
38 set_bit (int nr, volatile void *addr)
40 __u32 bit, old, new;
41 volatile __u32 *m;
42 CMPXCHG_BUGCHECK_DECL
44 m = (volatile __u32 *) addr + (nr >> 5);
45 bit = 1 << (nr & 31);
46 do {
47 CMPXCHG_BUGCHECK(m);
48 old = *m;
49 new = old | bit;
50 } while (cmpxchg_acq(m, old, new) != old);
53 /**
54 * __set_bit - Set a bit in memory
55 * @nr: the bit to set
56 * @addr: the address to start counting from
58 * Unlike set_bit(), this function is non-atomic and may be reordered.
59 * If it's called on the same region of memory simultaneously, the effect
60 * may be that only one operation succeeds.
62 static __inline__ void
63 __set_bit (int nr, volatile void *addr)
65 *((__u32 *) addr + (nr >> 5)) |= (1 << (nr & 31));
69 * clear_bit() has "acquire" semantics.
71 #define smp_mb__before_clear_bit() smp_mb()
72 #define smp_mb__after_clear_bit() do { /* skip */; } while (0)
74 /**
75 * clear_bit - Clears a bit in memory
76 * @nr: Bit to clear
77 * @addr: Address to start counting from
79 * clear_bit() is atomic and may not be reordered. However, it does
80 * not contain a memory barrier, so if it is used for locking purposes,
81 * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
82 * in order to ensure changes are visible on other processors.
84 static __inline__ void
85 clear_bit (int nr, volatile void *addr)
87 __u32 mask, old, new;
88 volatile __u32 *m;
89 CMPXCHG_BUGCHECK_DECL
91 m = (volatile __u32 *) addr + (nr >> 5);
92 mask = ~(1 << (nr & 31));
93 do {
94 CMPXCHG_BUGCHECK(m);
95 old = *m;
96 new = old & mask;
97 } while (cmpxchg_acq(m, old, new) != old);
101 * clear_bit_unlock - Clears a bit in memory with release
102 * @nr: Bit to clear
103 * @addr: Address to start counting from
105 * clear_bit_unlock() is atomic and may not be reordered. It does
106 * contain a memory barrier suitable for unlock type operations.
108 static __inline__ void
109 clear_bit_unlock (int nr, volatile void *addr)
111 __u32 mask, old, new;
112 volatile __u32 *m;
113 CMPXCHG_BUGCHECK_DECL
115 m = (volatile __u32 *) addr + (nr >> 5);
116 mask = ~(1 << (nr & 31));
117 do {
118 CMPXCHG_BUGCHECK(m);
119 old = *m;
120 new = old & mask;
121 } while (cmpxchg_rel(m, old, new) != old);
125 * __clear_bit_unlock - Non-atomically clears a bit in memory with release
126 * @nr: Bit to clear
127 * @addr: Address to start counting from
129 * Similarly to clear_bit_unlock, the implementation uses a store
130 * with release semantics. See also arch_spin_unlock().
132 static __inline__ void
133 __clear_bit_unlock(int nr, void *addr)
135 __u32 * const m = (__u32 *) addr + (nr >> 5);
136 __u32 const new = *m & ~(1 << (nr & 31));
138 ia64_st4_rel_nta(m, new);
142 * __clear_bit - Clears a bit in memory (non-atomic version)
143 * @nr: the bit to clear
144 * @addr: the address to start counting from
146 * Unlike clear_bit(), this function is non-atomic and may be reordered.
147 * If it's called on the same region of memory simultaneously, the effect
148 * may be that only one operation succeeds.
150 static __inline__ void
151 __clear_bit (int nr, volatile void *addr)
153 *((__u32 *) addr + (nr >> 5)) &= ~(1 << (nr & 31));
157 * change_bit - Toggle a bit in memory
158 * @nr: Bit to toggle
159 * @addr: Address to start counting from
161 * change_bit() is atomic and may not be reordered.
162 * Note that @nr may be almost arbitrarily large; this function is not
163 * restricted to acting on a single-word quantity.
165 static __inline__ void
166 change_bit (int nr, volatile void *addr)
168 __u32 bit, old, new;
169 volatile __u32 *m;
170 CMPXCHG_BUGCHECK_DECL
172 m = (volatile __u32 *) addr + (nr >> 5);
173 bit = (1 << (nr & 31));
174 do {
175 CMPXCHG_BUGCHECK(m);
176 old = *m;
177 new = old ^ bit;
178 } while (cmpxchg_acq(m, old, new) != old);
182 * __change_bit - Toggle a bit in memory
183 * @nr: the bit to toggle
184 * @addr: the address to start counting from
186 * Unlike change_bit(), this function is non-atomic and may be reordered.
187 * If it's called on the same region of memory simultaneously, the effect
188 * may be that only one operation succeeds.
190 static __inline__ void
191 __change_bit (int nr, volatile void *addr)
193 *((__u32 *) addr + (nr >> 5)) ^= (1 << (nr & 31));
197 * test_and_set_bit - Set a bit and return its old value
198 * @nr: Bit to set
199 * @addr: Address to count from
201 * This operation is atomic and cannot be reordered.
202 * It also implies the acquisition side of the memory barrier.
204 static __inline__ int
205 test_and_set_bit (int nr, volatile void *addr)
207 __u32 bit, old, new;
208 volatile __u32 *m;
209 CMPXCHG_BUGCHECK_DECL
211 m = (volatile __u32 *) addr + (nr >> 5);
212 bit = 1 << (nr & 31);
213 do {
214 CMPXCHG_BUGCHECK(m);
215 old = *m;
216 new = old | bit;
217 } while (cmpxchg_acq(m, old, new) != old);
218 return (old & bit) != 0;
222 * test_and_set_bit_lock - Set a bit and return its old value for lock
223 * @nr: Bit to set
224 * @addr: Address to count from
226 * This is the same as test_and_set_bit on ia64
228 #define test_and_set_bit_lock test_and_set_bit
231 * __test_and_set_bit - Set a bit and return its old value
232 * @nr: Bit to set
233 * @addr: Address to count from
235 * This operation is non-atomic and can be reordered.
236 * If two examples of this operation race, one can appear to succeed
237 * but actually fail. You must protect multiple accesses with a lock.
239 static __inline__ int
240 __test_and_set_bit (int nr, volatile void *addr)
242 __u32 *p = (__u32 *) addr + (nr >> 5);
243 __u32 m = 1 << (nr & 31);
244 int oldbitset = (*p & m) != 0;
246 *p |= m;
247 return oldbitset;
251 * test_and_clear_bit - Clear a bit and return its old value
252 * @nr: Bit to clear
253 * @addr: Address to count from
255 * This operation is atomic and cannot be reordered.
256 * It also implies the acquisition side of the memory barrier.
258 static __inline__ int
259 test_and_clear_bit (int nr, volatile void *addr)
261 __u32 mask, old, new;
262 volatile __u32 *m;
263 CMPXCHG_BUGCHECK_DECL
265 m = (volatile __u32 *) addr + (nr >> 5);
266 mask = ~(1 << (nr & 31));
267 do {
268 CMPXCHG_BUGCHECK(m);
269 old = *m;
270 new = old & mask;
271 } while (cmpxchg_acq(m, old, new) != old);
272 return (old & ~mask) != 0;
276 * __test_and_clear_bit - Clear a bit and return its old value
277 * @nr: Bit to clear
278 * @addr: Address to count from
280 * This operation is non-atomic and can be reordered.
281 * If two examples of this operation race, one can appear to succeed
282 * but actually fail. You must protect multiple accesses with a lock.
284 static __inline__ int
285 __test_and_clear_bit(int nr, volatile void * addr)
287 __u32 *p = (__u32 *) addr + (nr >> 5);
288 __u32 m = 1 << (nr & 31);
289 int oldbitset = (*p & m) != 0;
291 *p &= ~m;
292 return oldbitset;
296 * test_and_change_bit - Change a bit and return its old value
297 * @nr: Bit to change
298 * @addr: Address to count from
300 * This operation is atomic and cannot be reordered.
301 * It also implies the acquisition side of the memory barrier.
303 static __inline__ int
304 test_and_change_bit (int nr, volatile void *addr)
306 __u32 bit, old, new;
307 volatile __u32 *m;
308 CMPXCHG_BUGCHECK_DECL
310 m = (volatile __u32 *) addr + (nr >> 5);
311 bit = (1 << (nr & 31));
312 do {
313 CMPXCHG_BUGCHECK(m);
314 old = *m;
315 new = old ^ bit;
316 } while (cmpxchg_acq(m, old, new) != old);
317 return (old & bit) != 0;
321 * __test_and_change_bit - Change a bit and return its old value
322 * @nr: Bit to change
323 * @addr: Address to count from
325 * This operation is non-atomic and can be reordered.
327 static __inline__ int
328 __test_and_change_bit (int nr, void *addr)
330 __u32 old, bit = (1 << (nr & 31));
331 __u32 *m = (__u32 *) addr + (nr >> 5);
333 old = *m;
334 *m = old ^ bit;
335 return (old & bit) != 0;
338 static __inline__ int
339 test_bit (int nr, const volatile void *addr)
341 return 1 & (((const volatile __u32 *) addr)[nr >> 5] >> (nr & 31));
345 * ffz - find the first zero bit in a long word
346 * @x: The long word to find the bit in
348 * Returns the bit-number (0..63) of the first (least significant) zero bit.
349 * Undefined if no zero exists, so code should check against ~0UL first...
351 static inline unsigned long
352 ffz (unsigned long x)
354 unsigned long result;
356 result = ia64_popcnt(x & (~x - 1));
357 return result;
361 * __ffs - find first bit in word.
362 * @x: The word to search
364 * Undefined if no bit exists, so code should check against 0 first.
366 static __inline__ unsigned long
367 __ffs (unsigned long x)
369 unsigned long result;
371 result = ia64_popcnt((x-1) & ~x);
372 return result;
375 #ifdef __KERNEL__
378 * Return bit number of last (most-significant) bit set. Undefined
379 * for x==0. Bits are numbered from 0..63 (e.g., ia64_fls(9) == 3).
381 static inline unsigned long
382 ia64_fls (unsigned long x)
384 long double d = x;
385 long exp;
387 exp = ia64_getf_exp(d);
388 return exp - 0xffff;
392 * Find the last (most significant) bit set. Returns 0 for x==0 and
393 * bits are numbered from 1..32 (e.g., fls(9) == 4).
395 static inline int
396 fls (int t)
398 unsigned long x = t & 0xffffffffu;
400 if (!x)
401 return 0;
402 x |= x >> 1;
403 x |= x >> 2;
404 x |= x >> 4;
405 x |= x >> 8;
406 x |= x >> 16;
407 return ia64_popcnt(x);
411 * Find the last (most significant) bit set. Undefined for x==0.
412 * Bits are numbered from 0..63 (e.g., __fls(9) == 3).
414 static inline unsigned long
415 __fls (unsigned long x)
417 x |= x >> 1;
418 x |= x >> 2;
419 x |= x >> 4;
420 x |= x >> 8;
421 x |= x >> 16;
422 x |= x >> 32;
423 return ia64_popcnt(x) - 1;
426 #include <asm-generic/bitops/fls64.h>
428 #include <asm-generic/bitops/builtin-ffs.h>
431 * hweightN: returns the hamming weight (i.e. the number
432 * of bits set) of a N-bit word
434 static __inline__ unsigned long __arch_hweight64(unsigned long x)
436 unsigned long result;
437 result = ia64_popcnt(x);
438 return result;
441 #define __arch_hweight32(x) ((unsigned int) __arch_hweight64((x) & 0xfffffffful))
442 #define __arch_hweight16(x) ((unsigned int) __arch_hweight64((x) & 0xfffful))
443 #define __arch_hweight8(x) ((unsigned int) __arch_hweight64((x) & 0xfful))
445 #include <asm-generic/bitops/const_hweight.h>
447 #endif /* __KERNEL__ */
449 #include <asm-generic/bitops/find.h>
451 #ifdef __KERNEL__
453 #include <asm-generic/bitops/le.h>
455 #include <asm-generic/bitops/ext2-atomic-setbit.h>
457 #include <asm-generic/bitops/sched.h>
459 #endif /* __KERNEL__ */
461 #endif /* _ASM_IA64_BITOPS_H */