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 - 1997, 99, 2000, 06, 07 Ralf Baechle (ralf@linux-mips.org) 7 * Copyright (c) 1999, 2000 Silicon Graphics, Inc. 8 */ 9 #ifndef _ASM_BITOPS_H 10 #define _ASM_BITOPS_H 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/barrier.h> 19 #include <asm/byteorder.h> /* sigh ... */ 20 #include <asm/compiler.h> 21 #include <asm/cpu-features.h> 22 #include <asm/sgidefs.h> 23 #include <asm/war.h> 24 25 #if _MIPS_SZLONG == 32 26 #define SZLONG_LOG 5 27 #define SZLONG_MASK 31UL 28 #define __LL "ll " 29 #define __SC "sc " 30 #define __INS "ins " 31 #define __EXT "ext " 32 #elif _MIPS_SZLONG == 64 33 #define SZLONG_LOG 6 34 #define SZLONG_MASK 63UL 35 #define __LL "lld " 36 #define __SC "scd " 37 #define __INS "dins " 38 #define __EXT "dext " 39 #endif 40 41 /* 42 * These are the "slower" versions of the functions and are in bitops.c. 43 * These functions call raw_local_irq_{save,restore}(). 44 */ 45 void __mips_set_bit(unsigned long nr, volatile unsigned long *addr); 46 void __mips_clear_bit(unsigned long nr, volatile unsigned long *addr); 47 void __mips_change_bit(unsigned long nr, volatile unsigned long *addr); 48 int __mips_test_and_set_bit(unsigned long nr, 49 volatile unsigned long *addr); 50 int __mips_test_and_set_bit_lock(unsigned long nr, 51 volatile unsigned long *addr); 52 int __mips_test_and_clear_bit(unsigned long nr, 53 volatile unsigned long *addr); 54 int __mips_test_and_change_bit(unsigned long nr, 55 volatile unsigned long *addr); 56 57 58 /* 59 * set_bit - Atomically set a bit in memory 60 * @nr: the bit to set 61 * @addr: the address to start counting from 62 * 63 * This function is atomic and may not be reordered. See __set_bit() 64 * if you do not require the atomic guarantees. 65 * Note that @nr may be almost arbitrarily large; this function is not 66 * restricted to acting on a single-word quantity. 67 */ 68 static inline void set_bit(unsigned long nr, volatile unsigned long *addr) 69 { 70 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 71 int bit = nr & SZLONG_MASK; 72 unsigned long temp; 73 74 if (kernel_uses_llsc && R10000_LLSC_WAR) { 75 __asm__ __volatile__( 76 " .set arch=r4000 \n" 77 "1: " __LL "%0, %1 # set_bit \n" 78 " or %0, %2 \n" 79 " " __SC "%0, %1 \n" 80 " beqzl %0, 1b \n" 81 " .set mips0 \n" 82 : "=&r" (temp), "=" GCC_OFF_SMALL_ASM() (*m) 83 : "ir" (1UL << bit), GCC_OFF_SMALL_ASM() (*m)); 84 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6) 85 } else if (kernel_uses_llsc && __builtin_constant_p(bit)) { 86 do { 87 __asm__ __volatile__( 88 " " __LL "%0, %1 # set_bit \n" 89 " " __INS "%0, %3, %2, 1 \n" 90 " " __SC "%0, %1 \n" 91 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m) 92 : "ir" (bit), "r" (~0)); 93 } while (unlikely(!temp)); 94 #endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */ 95 } else if (kernel_uses_llsc) { 96 do { 97 __asm__ __volatile__( 98 " .set "MIPS_ISA_ARCH_LEVEL" \n" 99 " " __LL "%0, %1 # set_bit \n" 100 " or %0, %2 \n" 101 " " __SC "%0, %1 \n" 102 " .set mips0 \n" 103 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m) 104 : "ir" (1UL << bit)); 105 } while (unlikely(!temp)); 106 } else 107 __mips_set_bit(nr, addr); 108 } 109 110 /* 111 * clear_bit - Clears a bit in memory 112 * @nr: Bit to clear 113 * @addr: Address to start counting from 114 * 115 * clear_bit() is atomic and may not be reordered. However, it does 116 * not contain a memory barrier, so if it is used for locking purposes, 117 * you should call smp_mb__before_atomic() and/or smp_mb__after_atomic() 118 * in order to ensure changes are visible on other processors. 119 */ 120 static inline void clear_bit(unsigned long nr, volatile unsigned long *addr) 121 { 122 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 123 int bit = nr & SZLONG_MASK; 124 unsigned long temp; 125 126 if (kernel_uses_llsc && R10000_LLSC_WAR) { 127 __asm__ __volatile__( 128 " .set arch=r4000 \n" 129 "1: " __LL "%0, %1 # clear_bit \n" 130 " and %0, %2 \n" 131 " " __SC "%0, %1 \n" 132 " beqzl %0, 1b \n" 133 " .set mips0 \n" 134 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m) 135 : "ir" (~(1UL << bit))); 136 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6) 137 } else if (kernel_uses_llsc && __builtin_constant_p(bit)) { 138 do { 139 __asm__ __volatile__( 140 " " __LL "%0, %1 # clear_bit \n" 141 " " __INS "%0, $0, %2, 1 \n" 142 " " __SC "%0, %1 \n" 143 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m) 144 : "ir" (bit)); 145 } while (unlikely(!temp)); 146 #endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */ 147 } else if (kernel_uses_llsc) { 148 do { 149 __asm__ __volatile__( 150 " .set "MIPS_ISA_ARCH_LEVEL" \n" 151 " " __LL "%0, %1 # clear_bit \n" 152 " and %0, %2 \n" 153 " " __SC "%0, %1 \n" 154 " .set mips0 \n" 155 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m) 156 : "ir" (~(1UL << bit))); 157 } while (unlikely(!temp)); 158 } else 159 __mips_clear_bit(nr, addr); 160 } 161 162 /* 163 * clear_bit_unlock - Clears a bit in memory 164 * @nr: Bit to clear 165 * @addr: Address to start counting from 166 * 167 * clear_bit() is atomic and implies release semantics before the memory 168 * operation. It can be used for an unlock. 169 */ 170 static inline void clear_bit_unlock(unsigned long nr, volatile unsigned long *addr) 171 { 172 smp_mb__before_atomic(); 173 clear_bit(nr, addr); 174 } 175 176 /* 177 * change_bit - Toggle a bit in memory 178 * @nr: Bit to change 179 * @addr: Address to start counting from 180 * 181 * change_bit() is atomic and may not be reordered. 182 * Note that @nr may be almost arbitrarily large; this function is not 183 * restricted to acting on a single-word quantity. 184 */ 185 static inline void change_bit(unsigned long nr, volatile unsigned long *addr) 186 { 187 int bit = nr & SZLONG_MASK; 188 189 if (kernel_uses_llsc && R10000_LLSC_WAR) { 190 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 191 unsigned long temp; 192 193 __asm__ __volatile__( 194 " .set arch=r4000 \n" 195 "1: " __LL "%0, %1 # change_bit \n" 196 " xor %0, %2 \n" 197 " " __SC "%0, %1 \n" 198 " beqzl %0, 1b \n" 199 " .set mips0 \n" 200 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m) 201 : "ir" (1UL << bit)); 202 } else if (kernel_uses_llsc) { 203 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 204 unsigned long temp; 205 206 do { 207 __asm__ __volatile__( 208 " .set "MIPS_ISA_ARCH_LEVEL" \n" 209 " " __LL "%0, %1 # change_bit \n" 210 " xor %0, %2 \n" 211 " " __SC "%0, %1 \n" 212 " .set mips0 \n" 213 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m) 214 : "ir" (1UL << bit)); 215 } while (unlikely(!temp)); 216 } else 217 __mips_change_bit(nr, addr); 218 } 219 220 /* 221 * test_and_set_bit - Set a bit and return its old value 222 * @nr: Bit to set 223 * @addr: Address to count from 224 * 225 * This operation is atomic and cannot be reordered. 226 * It also implies a memory barrier. 227 */ 228 static inline int test_and_set_bit(unsigned long nr, 229 volatile unsigned long *addr) 230 { 231 int bit = nr & SZLONG_MASK; 232 unsigned long res; 233 234 smp_mb__before_llsc(); 235 236 if (kernel_uses_llsc && R10000_LLSC_WAR) { 237 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 238 unsigned long temp; 239 240 __asm__ __volatile__( 241 " .set arch=r4000 \n" 242 "1: " __LL "%0, %1 # test_and_set_bit \n" 243 " or %2, %0, %3 \n" 244 " " __SC "%2, %1 \n" 245 " beqzl %2, 1b \n" 246 " and %2, %0, %3 \n" 247 " .set mips0 \n" 248 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res) 249 : "r" (1UL << bit) 250 : "memory"); 251 } else if (kernel_uses_llsc) { 252 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 253 unsigned long temp; 254 255 do { 256 __asm__ __volatile__( 257 " .set "MIPS_ISA_ARCH_LEVEL" \n" 258 " " __LL "%0, %1 # test_and_set_bit \n" 259 " or %2, %0, %3 \n" 260 " " __SC "%2, %1 \n" 261 " .set mips0 \n" 262 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res) 263 : "r" (1UL << bit) 264 : "memory"); 265 } while (unlikely(!res)); 266 267 res = temp & (1UL << bit); 268 } else 269 res = __mips_test_and_set_bit(nr, addr); 270 271 smp_llsc_mb(); 272 273 return res != 0; 274 } 275 276 /* 277 * test_and_set_bit_lock - Set a bit and return its old value 278 * @nr: Bit to set 279 * @addr: Address to count from 280 * 281 * This operation is atomic and implies acquire ordering semantics 282 * after the memory operation. 283 */ 284 static inline int test_and_set_bit_lock(unsigned long nr, 285 volatile unsigned long *addr) 286 { 287 int bit = nr & SZLONG_MASK; 288 unsigned long res; 289 290 if (kernel_uses_llsc && R10000_LLSC_WAR) { 291 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 292 unsigned long temp; 293 294 __asm__ __volatile__( 295 " .set arch=r4000 \n" 296 "1: " __LL "%0, %1 # test_and_set_bit \n" 297 " or %2, %0, %3 \n" 298 " " __SC "%2, %1 \n" 299 " beqzl %2, 1b \n" 300 " and %2, %0, %3 \n" 301 " .set mips0 \n" 302 : "=&r" (temp), "+m" (*m), "=&r" (res) 303 : "r" (1UL << bit) 304 : "memory"); 305 } else if (kernel_uses_llsc) { 306 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 307 unsigned long temp; 308 309 do { 310 __asm__ __volatile__( 311 " .set "MIPS_ISA_ARCH_LEVEL" \n" 312 " " __LL "%0, %1 # test_and_set_bit \n" 313 " or %2, %0, %3 \n" 314 " " __SC "%2, %1 \n" 315 " .set mips0 \n" 316 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res) 317 : "r" (1UL << bit) 318 : "memory"); 319 } while (unlikely(!res)); 320 321 res = temp & (1UL << bit); 322 } else 323 res = __mips_test_and_set_bit_lock(nr, addr); 324 325 smp_llsc_mb(); 326 327 return res != 0; 328 } 329 /* 330 * test_and_clear_bit - Clear a bit and return its old value 331 * @nr: Bit to clear 332 * @addr: Address to count from 333 * 334 * This operation is atomic and cannot be reordered. 335 * It also implies a memory barrier. 336 */ 337 static inline int test_and_clear_bit(unsigned long nr, 338 volatile unsigned long *addr) 339 { 340 int bit = nr & SZLONG_MASK; 341 unsigned long res; 342 343 smp_mb__before_llsc(); 344 345 if (kernel_uses_llsc && R10000_LLSC_WAR) { 346 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 347 unsigned long temp; 348 349 __asm__ __volatile__( 350 " .set arch=r4000 \n" 351 "1: " __LL "%0, %1 # test_and_clear_bit \n" 352 " or %2, %0, %3 \n" 353 " xor %2, %3 \n" 354 " " __SC "%2, %1 \n" 355 " beqzl %2, 1b \n" 356 " and %2, %0, %3 \n" 357 " .set mips0 \n" 358 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res) 359 : "r" (1UL << bit) 360 : "memory"); 361 #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6) 362 } else if (kernel_uses_llsc && __builtin_constant_p(nr)) { 363 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 364 unsigned long temp; 365 366 do { 367 __asm__ __volatile__( 368 " " __LL "%0, %1 # test_and_clear_bit \n" 369 " " __EXT "%2, %0, %3, 1 \n" 370 " " __INS "%0, $0, %3, 1 \n" 371 " " __SC "%0, %1 \n" 372 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res) 373 : "ir" (bit) 374 : "memory"); 375 } while (unlikely(!temp)); 376 #endif 377 } else if (kernel_uses_llsc) { 378 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 379 unsigned long temp; 380 381 do { 382 __asm__ __volatile__( 383 " .set "MIPS_ISA_ARCH_LEVEL" \n" 384 " " __LL "%0, %1 # test_and_clear_bit \n" 385 " or %2, %0, %3 \n" 386 " xor %2, %3 \n" 387 " " __SC "%2, %1 \n" 388 " .set mips0 \n" 389 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res) 390 : "r" (1UL << bit) 391 : "memory"); 392 } while (unlikely(!res)); 393 394 res = temp & (1UL << bit); 395 } else 396 res = __mips_test_and_clear_bit(nr, addr); 397 398 smp_llsc_mb(); 399 400 return res != 0; 401 } 402 403 /* 404 * test_and_change_bit - Change a bit and return its old value 405 * @nr: Bit to change 406 * @addr: Address to count from 407 * 408 * This operation is atomic and cannot be reordered. 409 * It also implies a memory barrier. 410 */ 411 static inline int test_and_change_bit(unsigned long nr, 412 volatile unsigned long *addr) 413 { 414 int bit = nr & SZLONG_MASK; 415 unsigned long res; 416 417 smp_mb__before_llsc(); 418 419 if (kernel_uses_llsc && R10000_LLSC_WAR) { 420 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 421 unsigned long temp; 422 423 __asm__ __volatile__( 424 " .set arch=r4000 \n" 425 "1: " __LL "%0, %1 # test_and_change_bit \n" 426 " xor %2, %0, %3 \n" 427 " " __SC "%2, %1 \n" 428 " beqzl %2, 1b \n" 429 " and %2, %0, %3 \n" 430 " .set mips0 \n" 431 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res) 432 : "r" (1UL << bit) 433 : "memory"); 434 } else if (kernel_uses_llsc) { 435 unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); 436 unsigned long temp; 437 438 do { 439 __asm__ __volatile__( 440 " .set "MIPS_ISA_ARCH_LEVEL" \n" 441 " " __LL "%0, %1 # test_and_change_bit \n" 442 " xor %2, %0, %3 \n" 443 " " __SC "\t%2, %1 \n" 444 " .set mips0 \n" 445 : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res) 446 : "r" (1UL << bit) 447 : "memory"); 448 } while (unlikely(!res)); 449 450 res = temp & (1UL << bit); 451 } else 452 res = __mips_test_and_change_bit(nr, addr); 453 454 smp_llsc_mb(); 455 456 return res != 0; 457 } 458 459 #include <asm-generic/bitops/non-atomic.h> 460 461 /* 462 * __clear_bit_unlock - Clears a bit in memory 463 * @nr: Bit to clear 464 * @addr: Address to start counting from 465 * 466 * __clear_bit() is non-atomic and implies release semantics before the memory 467 * operation. It can be used for an unlock if no other CPUs can concurrently 468 * modify other bits in the word. 469 */ 470 static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *addr) 471 { 472 smp_mb(); 473 __clear_bit(nr, addr); 474 } 475 476 /* 477 * Return the bit position (0..63) of the most significant 1 bit in a word 478 * Returns -1 if no 1 bit exists 479 */ 480 static inline unsigned long __fls(unsigned long word) 481 { 482 int num; 483 484 if (BITS_PER_LONG == 32 && !__builtin_constant_p(word) && 485 __builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) { 486 __asm__( 487 " .set push \n" 488 " .set "MIPS_ISA_LEVEL" \n" 489 " clz %0, %1 \n" 490 " .set pop \n" 491 : "=r" (num) 492 : "r" (word)); 493 494 return 31 - num; 495 } 496 497 if (BITS_PER_LONG == 64 && !__builtin_constant_p(word) && 498 __builtin_constant_p(cpu_has_mips64) && cpu_has_mips64) { 499 __asm__( 500 " .set push \n" 501 " .set "MIPS_ISA_LEVEL" \n" 502 " dclz %0, %1 \n" 503 " .set pop \n" 504 : "=r" (num) 505 : "r" (word)); 506 507 return 63 - num; 508 } 509 510 num = BITS_PER_LONG - 1; 511 512 #if BITS_PER_LONG == 64 513 if (!(word & (~0ul << 32))) { 514 num -= 32; 515 word <<= 32; 516 } 517 #endif 518 if (!(word & (~0ul << (BITS_PER_LONG-16)))) { 519 num -= 16; 520 word <<= 16; 521 } 522 if (!(word & (~0ul << (BITS_PER_LONG-8)))) { 523 num -= 8; 524 word <<= 8; 525 } 526 if (!(word & (~0ul << (BITS_PER_LONG-4)))) { 527 num -= 4; 528 word <<= 4; 529 } 530 if (!(word & (~0ul << (BITS_PER_LONG-2)))) { 531 num -= 2; 532 word <<= 2; 533 } 534 if (!(word & (~0ul << (BITS_PER_LONG-1)))) 535 num -= 1; 536 return num; 537 } 538 539 /* 540 * __ffs - find first bit in word. 541 * @word: The word to search 542 * 543 * Returns 0..SZLONG-1 544 * Undefined if no bit exists, so code should check against 0 first. 545 */ 546 static inline unsigned long __ffs(unsigned long word) 547 { 548 return __fls(word & -word); 549 } 550 551 /* 552 * fls - find last bit set. 553 * @word: The word to search 554 * 555 * This is defined the same way as ffs. 556 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. 557 */ 558 static inline int fls(int x) 559 { 560 int r; 561 562 if (!__builtin_constant_p(x) && 563 __builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) { 564 __asm__( 565 " .set push \n" 566 " .set "MIPS_ISA_LEVEL" \n" 567 " clz %0, %1 \n" 568 " .set pop \n" 569 : "=r" (x) 570 : "r" (x)); 571 572 return 32 - x; 573 } 574 575 r = 32; 576 if (!x) 577 return 0; 578 if (!(x & 0xffff0000u)) { 579 x <<= 16; 580 r -= 16; 581 } 582 if (!(x & 0xff000000u)) { 583 x <<= 8; 584 r -= 8; 585 } 586 if (!(x & 0xf0000000u)) { 587 x <<= 4; 588 r -= 4; 589 } 590 if (!(x & 0xc0000000u)) { 591 x <<= 2; 592 r -= 2; 593 } 594 if (!(x & 0x80000000u)) { 595 x <<= 1; 596 r -= 1; 597 } 598 return r; 599 } 600 601 #include <asm-generic/bitops/fls64.h> 602 603 /* 604 * ffs - find first bit set. 605 * @word: The word to search 606 * 607 * This is defined the same way as 608 * the libc and compiler builtin ffs routines, therefore 609 * differs in spirit from the above ffz (man ffs). 610 */ 611 static inline int ffs(int word) 612 { 613 if (!word) 614 return 0; 615 616 return fls(word & -word); 617 } 618 619 #include <asm-generic/bitops/ffz.h> 620 #include <asm-generic/bitops/find.h> 621 622 #ifdef __KERNEL__ 623 624 #include <asm-generic/bitops/sched.h> 625 626 #include <asm/arch_hweight.h> 627 #include <asm-generic/bitops/const_hweight.h> 628 629 #include <asm-generic/bitops/le.h> 630 #include <asm-generic/bitops/ext2-atomic.h> 631 632 #endif /* __KERNEL__ */ 633 634 #endif /* _ASM_BITOPS_H */ 635