iwlwifi: mvm: fix version check for GEO_TX_POWER_LIMIT support
[linux/fpc-iii.git] / arch / x86 / include / asm / bitops.h
blob33611a74bfffaa4f4773217399ba310a28193905
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_BITOPS_H
3 #define _ASM_X86_BITOPS_H
5 /*
6 * Copyright 1992, Linus Torvalds.
8 * Note: inlines with more than a single statement should be marked
9 * __always_inline to avoid problems with older gcc's inlining heuristics.
12 #ifndef _LINUX_BITOPS_H
13 #error only <linux/bitops.h> can be included directly
14 #endif
16 #include <linux/compiler.h>
17 #include <asm/alternative.h>
18 #include <asm/rmwcc.h>
19 #include <asm/barrier.h>
21 #if BITS_PER_LONG == 32
22 # define _BITOPS_LONG_SHIFT 5
23 #elif BITS_PER_LONG == 64
24 # define _BITOPS_LONG_SHIFT 6
25 #else
26 # error "Unexpected BITS_PER_LONG"
27 #endif
29 #define BIT_64(n) (U64_C(1) << (n))
32 * These have to be done with inline assembly: that way the bit-setting
33 * is guaranteed to be atomic. All bit operations return 0 if the bit
34 * was cleared before the operation and != 0 if it was not.
36 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
39 #define RLONG_ADDR(x) "m" (*(volatile long *) (x))
40 #define WBYTE_ADDR(x) "+m" (*(volatile char *) (x))
42 #define ADDR RLONG_ADDR(addr)
45 * We do the locked ops that don't return the old value as
46 * a mask operation on a byte.
48 #define IS_IMMEDIATE(nr) (__builtin_constant_p(nr))
49 #define CONST_MASK_ADDR(nr, addr) WBYTE_ADDR((void *)(addr) + ((nr)>>3))
50 #define CONST_MASK(nr) (1 << ((nr) & 7))
52 /**
53 * set_bit - Atomically set a bit in memory
54 * @nr: the bit to set
55 * @addr: the address to start counting from
57 * This function is atomic and may not be reordered. See __set_bit()
58 * if you do not require the atomic guarantees.
60 * Note: there are no guarantees that this function will not be reordered
61 * on non x86 architectures, so if you are writing portable code,
62 * make sure not to rely on its reordering guarantees.
64 * Note that @nr may be almost arbitrarily large; this function is not
65 * restricted to acting on a single-word quantity.
67 static __always_inline void
68 set_bit(long nr, volatile unsigned long *addr)
70 if (IS_IMMEDIATE(nr)) {
71 asm volatile(LOCK_PREFIX "orb %1,%0"
72 : CONST_MASK_ADDR(nr, addr)
73 : "iq" ((u8)CONST_MASK(nr))
74 : "memory");
75 } else {
76 asm volatile(LOCK_PREFIX __ASM_SIZE(bts) " %1,%0"
77 : : RLONG_ADDR(addr), "Ir" (nr) : "memory");
81 /**
82 * __set_bit - Set a bit in memory
83 * @nr: the bit to set
84 * @addr: the address to start counting from
86 * Unlike set_bit(), this function is non-atomic and may be reordered.
87 * If it's called on the same region of memory simultaneously, the effect
88 * may be that only one operation succeeds.
90 static __always_inline void __set_bit(long nr, volatile unsigned long *addr)
92 asm volatile(__ASM_SIZE(bts) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
95 /**
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 __always_inline void
106 clear_bit(long nr, volatile unsigned long *addr)
108 if (IS_IMMEDIATE(nr)) {
109 asm volatile(LOCK_PREFIX "andb %1,%0"
110 : CONST_MASK_ADDR(nr, addr)
111 : "iq" ((u8)~CONST_MASK(nr)));
112 } else {
113 asm volatile(LOCK_PREFIX __ASM_SIZE(btr) " %1,%0"
114 : : RLONG_ADDR(addr), "Ir" (nr) : "memory");
119 * clear_bit_unlock - Clears a bit in memory
120 * @nr: Bit to clear
121 * @addr: Address to start counting from
123 * clear_bit() is atomic and implies release semantics before the memory
124 * operation. It can be used for an unlock.
126 static __always_inline void clear_bit_unlock(long nr, volatile unsigned long *addr)
128 barrier();
129 clear_bit(nr, addr);
132 static __always_inline void __clear_bit(long nr, volatile unsigned long *addr)
134 asm volatile(__ASM_SIZE(btr) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
137 static __always_inline bool clear_bit_unlock_is_negative_byte(long nr, volatile unsigned long *addr)
139 bool negative;
140 asm volatile(LOCK_PREFIX "andb %2,%1"
141 CC_SET(s)
142 : CC_OUT(s) (negative), WBYTE_ADDR(addr)
143 : "ir" ((char) ~(1 << nr)) : "memory");
144 return negative;
147 // Let everybody know we have it
148 #define clear_bit_unlock_is_negative_byte clear_bit_unlock_is_negative_byte
151 * __clear_bit_unlock - Clears a bit in memory
152 * @nr: Bit to clear
153 * @addr: Address to start counting from
155 * __clear_bit() is non-atomic and implies release semantics before the memory
156 * operation. It can be used for an unlock if no other CPUs can concurrently
157 * modify other bits in the word.
159 static __always_inline void __clear_bit_unlock(long nr, volatile unsigned long *addr)
161 __clear_bit(nr, addr);
165 * __change_bit - Toggle a bit in memory
166 * @nr: the bit to change
167 * @addr: the address to start counting from
169 * Unlike change_bit(), this function is non-atomic and may be reordered.
170 * If it's called on the same region of memory simultaneously, the effect
171 * may be that only one operation succeeds.
173 static __always_inline void __change_bit(long nr, volatile unsigned long *addr)
175 asm volatile(__ASM_SIZE(btc) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
179 * change_bit - Toggle a bit in memory
180 * @nr: Bit to change
181 * @addr: Address to start counting from
183 * change_bit() is atomic and may not be reordered.
184 * Note that @nr may be almost arbitrarily large; this function is not
185 * restricted to acting on a single-word quantity.
187 static __always_inline void change_bit(long nr, volatile unsigned long *addr)
189 if (IS_IMMEDIATE(nr)) {
190 asm volatile(LOCK_PREFIX "xorb %1,%0"
191 : CONST_MASK_ADDR(nr, addr)
192 : "iq" ((u8)CONST_MASK(nr)));
193 } else {
194 asm volatile(LOCK_PREFIX __ASM_SIZE(btc) " %1,%0"
195 : : RLONG_ADDR(addr), "Ir" (nr) : "memory");
200 * test_and_set_bit - Set a bit and return its old value
201 * @nr: Bit to set
202 * @addr: Address to count from
204 * This operation is atomic and cannot be reordered.
205 * It also implies a memory barrier.
207 static __always_inline bool test_and_set_bit(long nr, volatile unsigned long *addr)
209 GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(bts),
210 *addr, "Ir", nr, "%0", c);
214 * test_and_set_bit_lock - Set a bit and return its old value for lock
215 * @nr: Bit to set
216 * @addr: Address to count from
218 * This is the same as test_and_set_bit on x86.
220 static __always_inline bool
221 test_and_set_bit_lock(long nr, volatile unsigned long *addr)
223 return test_and_set_bit(nr, addr);
227 * __test_and_set_bit - Set a bit and return its old value
228 * @nr: Bit to set
229 * @addr: Address to count from
231 * This operation is non-atomic and can be reordered.
232 * If two examples of this operation race, one can appear to succeed
233 * but actually fail. You must protect multiple accesses with a lock.
235 static __always_inline bool __test_and_set_bit(long nr, volatile unsigned long *addr)
237 bool oldbit;
239 asm(__ASM_SIZE(bts) " %2,%1"
240 CC_SET(c)
241 : CC_OUT(c) (oldbit)
242 : ADDR, "Ir" (nr) : "memory");
243 return oldbit;
247 * test_and_clear_bit - Clear a bit and return its old value
248 * @nr: Bit to clear
249 * @addr: Address to count from
251 * This operation is atomic and cannot be reordered.
252 * It also implies a memory barrier.
254 static __always_inline bool test_and_clear_bit(long nr, volatile unsigned long *addr)
256 GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btr),
257 *addr, "Ir", nr, "%0", c);
261 * __test_and_clear_bit - Clear a bit and return its old value
262 * @nr: Bit to clear
263 * @addr: Address to count from
265 * This operation is non-atomic and can be reordered.
266 * If two examples of this operation race, one can appear to succeed
267 * but actually fail. You must protect multiple accesses with a lock.
269 * Note: the operation is performed atomically with respect to
270 * the local CPU, but not other CPUs. Portable code should not
271 * rely on this behaviour.
272 * KVM relies on this behaviour on x86 for modifying memory that is also
273 * accessed from a hypervisor on the same CPU if running in a VM: don't change
274 * this without also updating arch/x86/kernel/kvm.c
276 static __always_inline bool __test_and_clear_bit(long nr, volatile unsigned long *addr)
278 bool oldbit;
280 asm volatile(__ASM_SIZE(btr) " %2,%1"
281 CC_SET(c)
282 : CC_OUT(c) (oldbit)
283 : ADDR, "Ir" (nr) : "memory");
284 return oldbit;
287 /* WARNING: non atomic and it can be reordered! */
288 static __always_inline bool __test_and_change_bit(long nr, volatile unsigned long *addr)
290 bool oldbit;
292 asm volatile(__ASM_SIZE(btc) " %2,%1"
293 CC_SET(c)
294 : CC_OUT(c) (oldbit)
295 : ADDR, "Ir" (nr) : "memory");
297 return oldbit;
301 * test_and_change_bit - Change a bit and return its old value
302 * @nr: Bit to change
303 * @addr: Address to count from
305 * This operation is atomic and cannot be reordered.
306 * It also implies a memory barrier.
308 static __always_inline bool test_and_change_bit(long nr, volatile unsigned long *addr)
310 GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btc),
311 *addr, "Ir", nr, "%0", c);
314 static __always_inline bool constant_test_bit(long nr, const volatile unsigned long *addr)
316 return ((1UL << (nr & (BITS_PER_LONG-1))) &
317 (addr[nr >> _BITOPS_LONG_SHIFT])) != 0;
320 static __always_inline bool variable_test_bit(long nr, volatile const unsigned long *addr)
322 bool oldbit;
324 asm volatile(__ASM_SIZE(bt) " %2,%1"
325 CC_SET(c)
326 : CC_OUT(c) (oldbit)
327 : "m" (*(unsigned long *)addr), "Ir" (nr) : "memory");
329 return oldbit;
332 #if 0 /* Fool kernel-doc since it doesn't do macros yet */
334 * test_bit - Determine whether a bit is set
335 * @nr: bit number to test
336 * @addr: Address to start counting from
338 static bool test_bit(int nr, const volatile unsigned long *addr);
339 #endif
341 #define test_bit(nr, addr) \
342 (__builtin_constant_p((nr)) \
343 ? constant_test_bit((nr), (addr)) \
344 : variable_test_bit((nr), (addr)))
347 * __ffs - find first set bit in word
348 * @word: The word to search
350 * Undefined if no bit exists, so code should check against 0 first.
352 static __always_inline unsigned long __ffs(unsigned long word)
354 asm("rep; bsf %1,%0"
355 : "=r" (word)
356 : "rm" (word));
357 return word;
361 * ffz - find first zero bit in word
362 * @word: The word to search
364 * Undefined if no zero exists, so code should check against ~0UL first.
366 static __always_inline unsigned long ffz(unsigned long word)
368 asm("rep; bsf %1,%0"
369 : "=r" (word)
370 : "r" (~word));
371 return word;
375 * __fls: find last set bit in word
376 * @word: The word to search
378 * Undefined if no set bit exists, so code should check against 0 first.
380 static __always_inline unsigned long __fls(unsigned long word)
382 asm("bsr %1,%0"
383 : "=r" (word)
384 : "rm" (word));
385 return word;
388 #undef ADDR
390 #ifdef __KERNEL__
392 * ffs - find first set bit in word
393 * @x: the word to search
395 * This is defined the same way as the libc and compiler builtin ffs
396 * routines, therefore differs in spirit from the other bitops.
398 * ffs(value) returns 0 if value is 0 or the position of the first
399 * set bit if value is nonzero. The first (least significant) bit
400 * is at position 1.
402 static __always_inline int ffs(int x)
404 int r;
406 #ifdef CONFIG_X86_64
408 * AMD64 says BSFL won't clobber the dest reg if x==0; Intel64 says the
409 * dest reg is undefined if x==0, but their CPU architect says its
410 * value is written to set it to the same as before, except that the
411 * top 32 bits will be cleared.
413 * We cannot do this on 32 bits because at the very least some
414 * 486 CPUs did not behave this way.
416 asm("bsfl %1,%0"
417 : "=r" (r)
418 : "rm" (x), "0" (-1));
419 #elif defined(CONFIG_X86_CMOV)
420 asm("bsfl %1,%0\n\t"
421 "cmovzl %2,%0"
422 : "=&r" (r) : "rm" (x), "r" (-1));
423 #else
424 asm("bsfl %1,%0\n\t"
425 "jnz 1f\n\t"
426 "movl $-1,%0\n"
427 "1:" : "=r" (r) : "rm" (x));
428 #endif
429 return r + 1;
433 * fls - find last set bit in word
434 * @x: the word to search
436 * This is defined in a similar way as the libc and compiler builtin
437 * ffs, but returns the position of the most significant set bit.
439 * fls(value) returns 0 if value is 0 or the position of the last
440 * set bit if value is nonzero. The last (most significant) bit is
441 * at position 32.
443 static __always_inline int fls(int x)
445 int r;
447 #ifdef CONFIG_X86_64
449 * AMD64 says BSRL won't clobber the dest reg if x==0; Intel64 says the
450 * dest reg is undefined if x==0, but their CPU architect says its
451 * value is written to set it to the same as before, except that the
452 * top 32 bits will be cleared.
454 * We cannot do this on 32 bits because at the very least some
455 * 486 CPUs did not behave this way.
457 asm("bsrl %1,%0"
458 : "=r" (r)
459 : "rm" (x), "0" (-1));
460 #elif defined(CONFIG_X86_CMOV)
461 asm("bsrl %1,%0\n\t"
462 "cmovzl %2,%0"
463 : "=&r" (r) : "rm" (x), "rm" (-1));
464 #else
465 asm("bsrl %1,%0\n\t"
466 "jnz 1f\n\t"
467 "movl $-1,%0\n"
468 "1:" : "=r" (r) : "rm" (x));
469 #endif
470 return r + 1;
474 * fls64 - find last set bit in a 64-bit word
475 * @x: the word to search
477 * This is defined in a similar way as the libc and compiler builtin
478 * ffsll, but returns the position of the most significant set bit.
480 * fls64(value) returns 0 if value is 0 or the position of the last
481 * set bit if value is nonzero. The last (most significant) bit is
482 * at position 64.
484 #ifdef CONFIG_X86_64
485 static __always_inline int fls64(__u64 x)
487 int bitpos = -1;
489 * AMD64 says BSRQ won't clobber the dest reg if x==0; Intel64 says the
490 * dest reg is undefined if x==0, but their CPU architect says its
491 * value is written to set it to the same as before.
493 asm("bsrq %1,%q0"
494 : "+r" (bitpos)
495 : "rm" (x));
496 return bitpos + 1;
498 #else
499 #include <asm-generic/bitops/fls64.h>
500 #endif
502 #include <asm-generic/bitops/find.h>
504 #include <asm-generic/bitops/sched.h>
506 #include <asm/arch_hweight.h>
508 #include <asm-generic/bitops/const_hweight.h>
510 #include <asm-generic/bitops/le.h>
512 #include <asm-generic/bitops/ext2-atomic-setbit.h>
514 #endif /* __KERNEL__ */
515 #endif /* _ASM_X86_BITOPS_H */