include/asm-blackfin/bitops.h

   1 /*
   2  * U-boot - bitops.h Routines for bit operations
   3  *
   4  * Copyright (c) 2005-2007 Analog Devices Inc.
   5  *
   6  * See file CREDITS for list of people who contributed to this
   7  * project.
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation; either version 2 of
  12  * the License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  22  * MA 02110-1301 USA
  23  */
  24
  25 #ifndef _BLACKFIN_BITOPS_H
  26 #define _BLACKFIN_BITOPS_H
  27
  28 /*
  29  * Copyright 1992, Linus Torvalds.
  30  */
  31
  32 #include <linux/config.h>
  33 #include <asm/byteorder.h>
  34 #include <asm/system.h>
  35
  36 #ifdef __KERNEL__
  37 /*
  38  * Function prototypes to keep gcc -Wall happy
  39  */
  40
  41 /*
  42  * The __ functions are not atomic
  43  */
  44
  45 /*
  46  * ffz = Find First Zero in word. Undefined if no zero exists,
  47  * so code should check against ~0UL first..
  48  */
  49 static __inline__ unsigned long ffz(unsigned long word)
  50 {
  51         unsigned long result = 0;
  52
  53         while (word & 1) {
  54                 result++;
  55                 word >>= 1;
  56         }
  57         return result;
  58 }
  59
  60 static __inline__ void set_bit(int nr, volatile void *addr)
  61 {
  62         int *a = (int *)addr;
  63         int mask;
  64         unsigned long flags;
  65
  66         a += nr >> 5;
  67         mask = 1 << (nr & 0x1f);
  68         local_irq_save(flags);
  69         *a |= mask;
  70         local_irq_restore(flags);
  71 }
  72
  73 static __inline__ void __set_bit(int nr, volatile void *addr)
  74 {
  75         int *a = (int *)addr;
  76         int mask;
  77
  78         a += nr >> 5;
  79         mask = 1 << (nr & 0x1f);
  80         *a |= mask;
  81 }
  82
  83 /*
  84  * clear_bit() doesn't provide any barrier for the compiler.
  85  */
  86 #define smp_mb__before_clear_bit()      barrier()
  87 #define smp_mb__after_clear_bit()       barrier()
  88
  89 static __inline__ void clear_bit(int nr, volatile void *addr)
  90 {
  91         int *a = (int *)addr;
  92         int mask;
  93         unsigned long flags;
  94
  95         a += nr >> 5;
  96         mask = 1 << (nr & 0x1f);
  97         local_irq_save(flags);
  98         *a &= ~mask;
  99         local_irq_restore(flags);
 100 }
 101
 102 static __inline__ void change_bit(int nr, volatile void *addr)
 103 {
 104         int mask, flags;
 105         unsigned long *ADDR = (unsigned long *)addr;
 106
 107         ADDR += nr >> 5;
 108         mask = 1 << (nr & 31);
 109         local_irq_save(flags);
 110         *ADDR ^= mask;
 111         local_irq_restore(flags);
 112 }
 113
 114 static __inline__ void __change_bit(int nr, volatile void *addr)
 115 {
 116         int mask;
 117         unsigned long *ADDR = (unsigned long *)addr;
 118
 119         ADDR += nr >> 5;
 120         mask = 1 << (nr & 31);
 121         *ADDR ^= mask;
 122 }
 123
 124 static __inline__ int test_and_set_bit(int nr, volatile void *addr)
 125 {
 126         int mask, retval;
 127         volatile unsigned int *a = (volatile unsigned int *)addr;
 128         unsigned long flags;
 129
 130         a += nr >> 5;
 131         mask = 1 << (nr & 0x1f);
 132         local_irq_save(flags);
 133         retval = (mask & *a) != 0;
 134         *a |= mask;
 135         local_irq_restore(flags);
 136
 137         return retval;
 138 }
 139
 140 static __inline__ int __test_and_set_bit(int nr, volatile void *addr)
 141 {
 142         int mask, retval;
 143         volatile unsigned int *a = (volatile unsigned int *)addr;
 144
 145         a += nr >> 5;
 146         mask = 1 << (nr & 0x1f);
 147         retval = (mask & *a) != 0;
 148         *a |= mask;
 149         return retval;
 150 }
 151
 152 static __inline__ int test_and_clear_bit(int nr, volatile void *addr)
 153 {
 154         int mask, retval;
 155         volatile unsigned int *a = (volatile unsigned int *)addr;
 156         unsigned long flags;
 157
 158         a += nr >> 5;
 159         mask = 1 << (nr & 0x1f);
 160         local_irq_save(flags);
 161         retval = (mask & *a) != 0;
 162         *a &= ~mask;
 163         local_irq_restore(flags);
 164
 165         return retval;
 166 }
 167
 168 static __inline__ int __test_and_clear_bit(int nr, volatile void *addr)
 169 {
 170         int mask, retval;
 171         volatile unsigned int *a = (volatile unsigned int *)addr;
 172
 173         a += nr >> 5;
 174         mask = 1 << (nr & 0x1f);
 175         retval = (mask & *a) != 0;
 176         *a &= ~mask;
 177         return retval;
 178 }
 179
 180 static __inline__ int test_and_change_bit(int nr, volatile void *addr)
 181 {
 182         int mask, retval;
 183         volatile unsigned int *a = (volatile unsigned int *)addr;
 184         unsigned long flags;
 185
 186         a += nr >> 5;
 187         mask = 1 << (nr & 0x1f);
 188         local_irq_save(flags);
 189         retval = (mask & *a) != 0;
 190         *a ^= mask;
 191         local_irq_restore(flags);
 192
 193         return retval;
 194 }
 195
 196 static __inline__ int __test_and_change_bit(int nr, volatile void *addr)
 197 {
 198         int mask, retval;
 199         volatile unsigned int *a = (volatile unsigned int *)addr;
 200
 201         a += nr >> 5;
 202         mask = 1 << (nr & 0x1f);
 203         retval = (mask & *a) != 0;
 204         *a ^= mask;
 205         return retval;
 206 }
 207
 208 /*
 209  * This routine doesn't need to be atomic.
 210  */
 211 static __inline__ int __constant_test_bit(int nr, const volatile void *addr)
 212 {
 213         return ((1UL << (nr & 31)) &
 214                 (((const volatile unsigned int *)addr)[nr >> 5])) != 0;
 215 }
 216
 217 static __inline__ int __test_bit(int nr, volatile void *addr)
 218 {
 219         int *a = (int *)addr;
 220         int mask;
 221
 222         a += nr >> 5;
 223         mask = 1 << (nr & 0x1f);
 224         return ((mask & *a) != 0);
 225 }
 226
 227 #define test_bit(nr,addr) \
 228 (__builtin_constant_p(nr) ? \
 229  __constant_test_bit((nr),(addr)) : \
 230  __test_bit((nr),(addr)))
 231
 232 #define find_first_zero_bit(addr, size) \
 233         find_next_zero_bit((addr), (size), 0)
 234
 235 static __inline__ int find_next_zero_bit(void *addr, int size, int offset)
 236 {
 237         unsigned long *p = ((unsigned long *)addr) + (offset >> 5);
 238         unsigned long result = offset & ~31UL;
 239         unsigned long tmp;
 240
 241         if (offset >= size)
 242                 return size;
 243         size -= result;
 244         offset &= 31UL;
 245         if (offset) {
 246                 tmp = *(p++);
 247                 tmp |= ~0UL >> (32 - offset);
 248                 if (size < 32)
 249                         goto found_first;
 250                 if (~tmp)
 251                         goto found_middle;
 252                 size -= 32;
 253                 result += 32;
 254         }
 255         while (size & ~31UL) {
 256                 if (~(tmp = *(p++)))
 257                         goto found_middle;
 258                 result += 32;
 259                 size -= 32;
 260         }
 261         if (!size)
 262                 return result;
 263         tmp = *p;
 264
 265       found_first:
 266         tmp |= ~0UL >> size;
 267       found_middle:
 268         return result + ffz(tmp);
 269 }
 270
 271 /*
 272  * ffs: find first bit set. This is defined the same way as
 273  * the libc and compiler builtin ffs routines, therefore
 274  * differs in spirit from the above ffz (man ffs).
 275  */
 276
 277 #define ffs(x)          generic_ffs(x)
 278
 279 /*
 280  * hweightN: returns the hamming weight (i.e. the number
 281  * of bits set) of a N-bit word
 282  */
 283
 284 #define hweight32(x)    generic_hweight32(x)
 285 #define hweight16(x)    generic_hweight16(x)
 286 #define hweight8(x)     generic_hweight8(x)
 287
 288 static __inline__ int ext2_set_bit(int nr, volatile void *addr)
 289 {
 290         int mask, retval;
 291         unsigned long flags;
 292         volatile unsigned char *ADDR = (unsigned char *)addr;
 293
 294         ADDR += nr >> 3;
 295         mask = 1 << (nr & 0x07);
 296         local_irq_save(flags);
 297         retval = (mask & *ADDR) != 0;
 298         *ADDR |= mask;
 299         local_irq_restore(flags);
 300         return retval;
 301 }
 302
 303 static __inline__ int ext2_clear_bit(int nr, volatile void *addr)
 304 {
 305         int mask, retval;
 306         unsigned long flags;
 307         volatile unsigned char *ADDR = (unsigned char *)addr;
 308
 309         ADDR += nr >> 3;
 310         mask = 1 << (nr & 0x07);
 311         local_irq_save(flags);
 312         retval = (mask & *ADDR) != 0;
 313         *ADDR &= ~mask;
 314         local_irq_restore(flags);
 315         return retval;
 316 }
 317
 318 static __inline__ int ext2_test_bit(int nr, const volatile void *addr)
 319 {
 320         int mask;
 321         const volatile unsigned char *ADDR = (const unsigned char *)addr;
 322
 323         ADDR += nr >> 3;
 324         mask = 1 << (nr & 0x07);
 325         return ((mask & *ADDR) != 0);
 326 }
 327
 328 #define ext2_find_first_zero_bit(addr, size) \
 329         ext2_find_next_zero_bit((addr), (size), 0)
 330
 331 static __inline__ unsigned long ext2_find_next_zero_bit(void *addr,
 332                                                         unsigned long size,
 333                                                         unsigned long offset)
 334 {
 335         unsigned long *p = ((unsigned long *)addr) + (offset >> 5);
 336         unsigned long result = offset & ~31UL;
 337         unsigned long tmp;
 338
 339         if (offset >= size)
 340                 return size;
 341         size -= result;
 342         offset &= 31UL;
 343         if (offset) {
 344                 tmp = *(p++);
 345                 tmp |= ~0UL >> (32 - offset);
 346                 if (size < 32)
 347                         goto found_first;
 348                 if (~tmp)
 349                         goto found_middle;
 350                 size -= 32;
 351                 result += 32;
 352         }
 353         while (size & ~31UL) {
 354                 if (~(tmp = *(p++)))
 355                         goto found_middle;
 356                 result += 32;
 357                 size -= 32;
 358         }
 359         if (!size)
 360                 return result;
 361         tmp = *p;
 362
 363       found_first:
 364         tmp |= ~0UL >> size;
 365       found_middle:
 366         return result + ffz(tmp);
 367 }
 368
 369 /* Bitmap functions for the minix filesystem. */
 370 #define minix_test_and_set_bit(nr,addr)         test_and_set_bit(nr,addr)
 371 #define minix_set_bit(nr,addr)                  set_bit(nr,addr)
 372 #define minix_test_and_clear_bit(nr,addr)       test_and_clear_bit(nr,addr)
 373 #define minix_test_bit(nr,addr)                 test_bit(nr,addr)
 374 #define minix_find_first_zero_bit(addr,size)    find_first_zero_bit(addr,size)
 375
 376 #endif
 377
 378 #endif