include/asm-avr32/bitops.h

   1 /*
   2  * Copyright (C) 2004-2006 Atmel Corporation
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8 #ifndef __ASM_AVR32_BITOPS_H
   9 #define __ASM_AVR32_BITOPS_H
  10
  11 #ifndef _LINUX_BITOPS_H
  12 #error only <linux/bitops.h> can be included directly
  13 #endif
  14
  15 #include <asm/byteorder.h>
  16 #include <asm/system.h>
  17
  18 /*
  19  * clear_bit() doesn't provide any barrier for the compiler
  20  */
  21 #define smp_mb__before_clear_bit()      barrier()
  22 #define smp_mb__after_clear_bit()       barrier()
  23
  24 /*
  25  * set_bit - Atomically set a bit in memory
  26  * @nr: the bit to set
  27  * @addr: the address to start counting from
  28  *
  29  * This function is atomic and may not be reordered.  See __set_bit()
  30  * if you do not require the atomic guarantees.
  31  *
  32  * Note that @nr may be almost arbitrarily large; this function is not
  33  * restricted to acting on a single-word quantity.
  34  */
  35 static inline void set_bit(int nr, volatile void * addr)
  36 {
  37         unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
  38         unsigned long tmp;
  39
  40         if (__builtin_constant_p(nr)) {
  41                 asm volatile(
  42                         "1:     ssrf    5\n"
  43                         "       ld.w    %0, %2\n"
  44                         "       sbr     %0, %3\n"
  45                         "       stcond  %1, %0\n"
  46                         "       brne    1b"
  47                         : "=&r"(tmp), "=o"(*p)
  48                         : "m"(*p), "i"(nr)
  49                         : "cc");
  50         } else {
  51                 unsigned long mask = 1UL << (nr % BITS_PER_LONG);
  52                 asm volatile(
  53                         "1:     ssrf    5\n"
  54                         "       ld.w    %0, %2\n"
  55                         "       or      %0, %3\n"
  56                         "       stcond  %1, %0\n"
  57                         "       brne    1b"
  58                         : "=&r"(tmp), "=o"(*p)
  59                         : "m"(*p), "r"(mask)
  60                         : "cc");
  61         }
  62 }
  63
  64 /*
  65  * clear_bit - Clears a bit in memory
  66  * @nr: Bit to clear
  67  * @addr: Address to start counting from
  68  *
  69  * clear_bit() is atomic and may not be reordered.  However, it does
  70  * not contain a memory barrier, so if it is used for locking purposes,
  71  * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
  72  * in order to ensure changes are visible on other processors.
  73  */
  74 static inline void clear_bit(int nr, volatile void * addr)
  75 {
  76         unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
  77         unsigned long tmp;
  78
  79         if (__builtin_constant_p(nr)) {
  80                 asm volatile(
  81                         "1:     ssrf    5\n"
  82                         "       ld.w    %0, %2\n"
  83                         "       cbr     %0, %3\n"
  84                         "       stcond  %1, %0\n"
  85                         "       brne    1b"
  86                         : "=&r"(tmp), "=o"(*p)
  87                         : "m"(*p), "i"(nr)
  88                         : "cc");
  89         } else {
  90                 unsigned long mask = 1UL << (nr % BITS_PER_LONG);
  91                 asm volatile(
  92                         "1:     ssrf    5\n"
  93                         "       ld.w    %0, %2\n"
  94                         "       andn    %0, %3\n"
  95                         "       stcond  %1, %0\n"
  96                         "       brne    1b"
  97                         : "=&r"(tmp), "=o"(*p)
  98                         : "m"(*p), "r"(mask)
  99                         : "cc");
 100         }
 101 }
 102
 103 /*
 104  * change_bit - Toggle a bit in memory
 105  * @nr: Bit to change
 106  * @addr: Address to start counting from
 107  *
 108  * change_bit() is atomic and may not be reordered.
 109  * Note that @nr may be almost arbitrarily large; this function is not
 110  * restricted to acting on a single-word quantity.
 111  */
 112 static inline void change_bit(int nr, volatile void * addr)
 113 {
 114         unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
 115         unsigned long mask = 1UL << (nr % BITS_PER_LONG);
 116         unsigned long tmp;
 117
 118         asm volatile(
 119                 "1:     ssrf    5\n"
 120                 "       ld.w    %0, %2\n"
 121                 "       eor     %0, %3\n"
 122                 "       stcond  %1, %0\n"
 123                 "       brne    1b"
 124                 : "=&r"(tmp), "=o"(*p)
 125                 : "m"(*p), "r"(mask)
 126                 : "cc");
 127 }
 128
 129 /*
 130  * test_and_set_bit - Set a bit and return its old value
 131  * @nr: Bit to set
 132  * @addr: Address to count from
 133  *
 134  * This operation is atomic and cannot be reordered.
 135  * It also implies a memory barrier.
 136  */
 137 static inline int test_and_set_bit(int nr, volatile void * addr)
 138 {
 139         unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
 140         unsigned long mask = 1UL << (nr % BITS_PER_LONG);
 141         unsigned long tmp, old;
 142
 143         if (__builtin_constant_p(nr)) {
 144                 asm volatile(
 145                         "1:     ssrf    5\n"
 146                         "       ld.w    %0, %3\n"
 147                         "       mov     %2, %0\n"
 148                         "       sbr     %0, %4\n"
 149                         "       stcond  %1, %0\n"
 150                         "       brne    1b"
 151                         : "=&r"(tmp), "=o"(*p), "=&r"(old)
 152                         : "m"(*p), "i"(nr)
 153                         : "memory", "cc");
 154         } else {
 155                 asm volatile(
 156                         "1:     ssrf    5\n"
 157                         "       ld.w    %2, %3\n"
 158                         "       or      %0, %2, %4\n"
 159                         "       stcond  %1, %0\n"
 160                         "       brne    1b"
 161                         : "=&r"(tmp), "=o"(*p), "=&r"(old)
 162                         : "m"(*p), "r"(mask)
 163                         : "memory", "cc");
 164         }
 165
 166         return (old & mask) != 0;
 167 }
 168
 169 /*
 170  * test_and_clear_bit - Clear a bit and return its old value
 171  * @nr: Bit to clear
 172  * @addr: Address to count from
 173  *
 174  * This operation is atomic and cannot be reordered.
 175  * It also implies a memory barrier.
 176  */
 177 static inline int test_and_clear_bit(int nr, volatile void * addr)
 178 {
 179         unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
 180         unsigned long mask = 1UL << (nr % BITS_PER_LONG);
 181         unsigned long tmp, old;
 182
 183         if (__builtin_constant_p(nr)) {
 184                 asm volatile(
 185                         "1:     ssrf    5\n"
 186                         "       ld.w    %0, %3\n"
 187                         "       mov     %2, %0\n"
 188                         "       cbr     %0, %4\n"
 189                         "       stcond  %1, %0\n"
 190                         "       brne    1b"
 191                         : "=&r"(tmp), "=o"(*p), "=&r"(old)
 192                         : "m"(*p), "i"(nr)
 193                         : "memory", "cc");
 194         } else {
 195                 asm volatile(
 196                         "1:     ssrf    5\n"
 197                         "       ld.w    %0, %3\n"
 198                         "       mov     %2, %0\n"
 199                         "       andn    %0, %4\n"
 200                         "       stcond  %1, %0\n"
 201                         "       brne    1b"
 202                         : "=&r"(tmp), "=o"(*p), "=&r"(old)
 203                         : "m"(*p), "r"(mask)
 204                         : "memory", "cc");
 205         }
 206
 207         return (old & mask) != 0;
 208 }
 209
 210 /*
 211  * test_and_change_bit - Change a bit and return its old value
 212  * @nr: Bit to change
 213  * @addr: Address to count from
 214  *
 215  * This operation is atomic and cannot be reordered.
 216  * It also implies a memory barrier.
 217  */
 218 static inline int test_and_change_bit(int nr, volatile void * addr)
 219 {
 220         unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
 221         unsigned long mask = 1UL << (nr % BITS_PER_LONG);
 222         unsigned long tmp, old;
 223
 224         asm volatile(
 225                 "1:     ssrf    5\n"
 226                 "       ld.w    %2, %3\n"
 227                 "       eor     %0, %2, %4\n"
 228                 "       stcond  %1, %0\n"
 229                 "       brne    1b"
 230                 : "=&r"(tmp), "=o"(*p), "=&r"(old)
 231                 : "m"(*p), "r"(mask)
 232                 : "memory", "cc");
 233
 234         return (old & mask) != 0;
 235 }
 236
 237 #include <asm-generic/bitops/non-atomic.h>
 238
 239 /* Find First bit Set */
 240 static inline unsigned long __ffs(unsigned long word)
 241 {
 242         unsigned long result;
 243
 244         asm("brev %1\n\t"
 245             "clz %0,%1"
 246             : "=r"(result), "=&r"(word)
 247             : "1"(word));
 248         return result;
 249 }
 250
 251 /* Find First Zero */
 252 static inline unsigned long ffz(unsigned long word)
 253 {
 254         return __ffs(~word);
 255 }
 256
 257 /* Find Last bit Set */
 258 static inline int fls(unsigned long word)
 259 {
 260         unsigned long result;
 261
 262         asm("clz %0,%1" : "=r"(result) : "r"(word));
 263         return 32 - result;
 264 }
 265
 266 unsigned long find_first_zero_bit(const unsigned long *addr,
 267                                   unsigned long size);
 268 unsigned long find_next_zero_bit(const unsigned long *addr,
 269                                  unsigned long size,
 270                                  unsigned long offset);
 271 unsigned long find_first_bit(const unsigned long *addr,
 272                              unsigned long size);
 273 unsigned long find_next_bit(const unsigned long *addr,
 274                                  unsigned long size,
 275                                  unsigned long offset);
 276
 277 /*
 278  * ffs: find first bit set. This is defined the same way as
 279  * the libc and compiler builtin ffs routines, therefore
 280  * differs in spirit from the above ffz (man ffs).
 281  *
 282  * The difference is that bit numbering starts at 1, and if no bit is set,
 283  * the function returns 0.
 284  */
 285 static inline int ffs(unsigned long word)
 286 {
 287         if(word == 0)
 288                 return 0;
 289         return __ffs(word) + 1;
 290 }
 291
 292 #include <asm-generic/bitops/fls64.h>
 293 #include <asm-generic/bitops/sched.h>
 294 #include <asm-generic/bitops/hweight.h>
 295 #include <asm-generic/bitops/lock.h>
 296
 297 #include <asm-generic/bitops/ext2-non-atomic.h>
 298 #include <asm-generic/bitops/ext2-atomic.h>
 299 #include <asm-generic/bitops/minix-le.h>
 300
 301 #endif /* __ASM_AVR32_BITOPS_H */