arch/frv/include/asm/bitops.h

   1 /* bitops.h: bit operations for the Fujitsu FR-V CPUs
   2  *
   3  * For an explanation of how atomic ops work in this arch, see:
   4  *   Documentation/frv/atomic-ops.txt
   5  *
   6  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
   7  * Written by David Howells (dhowells@redhat.com)
   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
  11  * as published by the Free Software Foundation; either version
  12  * 2 of the License, or (at your option) any later version.
  13  */
  14 #ifndef _ASM_BITOPS_H
  15 #define _ASM_BITOPS_H
  16
  17 #include <linux/compiler.h>
  18 #include <asm/byteorder.h>
  19
  20 #ifdef __KERNEL__
  21
  22 #ifndef _LINUX_BITOPS_H
  23 #error only <linux/bitops.h> can be included directly
  24 #endif
  25
  26 #include <asm-generic/bitops/ffz.h>
  27
  28 #include <asm/atomic.h>
  29
  30 static inline int test_and_clear_bit(unsigned long nr, volatile void *addr)
  31 {
  32         unsigned int *ptr = (void *)addr;
  33         unsigned int mask = 1UL << (nr & 31);
  34         ptr += nr >> 5;
  35         return (__atomic32_fetch_and(~mask, ptr) & mask) != 0;
  36 }
  37
  38 static inline int test_and_set_bit(unsigned long nr, volatile void *addr)
  39 {
  40         unsigned int *ptr = (void *)addr;
  41         unsigned int mask = 1UL << (nr & 31);
  42         ptr += nr >> 5;
  43         return (__atomic32_fetch_or(mask, ptr) & mask) != 0;
  44 }
  45
  46 static inline int test_and_change_bit(unsigned long nr, volatile void *addr)
  47 {
  48         unsigned int *ptr = (void *)addr;
  49         unsigned int mask = 1UL << (nr & 31);
  50         ptr += nr >> 5;
  51         return (__atomic32_fetch_xor(mask, ptr) & mask) != 0;
  52 }
  53
  54 static inline void clear_bit(unsigned long nr, volatile void *addr)
  55 {
  56         test_and_clear_bit(nr, addr);
  57 }
  58
  59 static inline void set_bit(unsigned long nr, volatile void *addr)
  60 {
  61         test_and_set_bit(nr, addr);
  62 }
  63
  64 static inline void change_bit(unsigned long nr, volatile void *addr)
  65 {
  66         test_and_change_bit(nr, addr);
  67 }
  68
  69 static inline void __clear_bit(unsigned long nr, volatile void *addr)
  70 {
  71         volatile unsigned long *a = addr;
  72         int mask;
  73
  74         a += nr >> 5;
  75         mask = 1 << (nr & 31);
  76         *a &= ~mask;
  77 }
  78
  79 static inline void __set_bit(unsigned long nr, volatile void *addr)
  80 {
  81         volatile unsigned long *a = addr;
  82         int mask;
  83
  84         a += nr >> 5;
  85         mask = 1 << (nr & 31);
  86         *a |= mask;
  87 }
  88
  89 static inline void __change_bit(unsigned long nr, volatile void *addr)
  90 {
  91         volatile unsigned long *a = addr;
  92         int mask;
  93
  94         a += nr >> 5;
  95         mask = 1 << (nr & 31);
  96         *a ^= mask;
  97 }
  98
  99 static inline int __test_and_clear_bit(unsigned long nr, volatile void *addr)
 100 {
 101         volatile unsigned long *a = addr;
 102         int mask, retval;
 103
 104         a += nr >> 5;
 105         mask = 1 << (nr & 31);
 106         retval = (mask & *a) != 0;
 107         *a &= ~mask;
 108         return retval;
 109 }
 110
 111 static inline int __test_and_set_bit(unsigned long nr, volatile void *addr)
 112 {
 113         volatile unsigned long *a = addr;
 114         int mask, retval;
 115
 116         a += nr >> 5;
 117         mask = 1 << (nr & 31);
 118         retval = (mask & *a) != 0;
 119         *a |= mask;
 120         return retval;
 121 }
 122
 123 static inline int __test_and_change_bit(unsigned long nr, volatile void *addr)
 124 {
 125         volatile unsigned long *a = addr;
 126         int mask, retval;
 127
 128         a += nr >> 5;
 129         mask = 1 << (nr & 31);
 130         retval = (mask & *a) != 0;
 131         *a ^= mask;
 132         return retval;
 133 }
 134
 135 /*
 136  * This routine doesn't need to be atomic.
 137  */
 138 static inline int
 139 __constant_test_bit(unsigned long nr, const volatile void *addr)
 140 {
 141         return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0;
 142 }
 143
 144 static inline int __test_bit(unsigned long nr, const volatile void *addr)
 145 {
 146         int     * a = (int *) addr;
 147         int     mask;
 148
 149         a += nr >> 5;
 150         mask = 1 << (nr & 0x1f);
 151         return ((mask & *a) != 0);
 152 }
 153
 154 #define test_bit(nr,addr) \
 155 (__builtin_constant_p(nr) ? \
 156  __constant_test_bit((nr),(addr)) : \
 157  __test_bit((nr),(addr)))
 158
 159 #include <asm-generic/bitops/find.h>
 160
 161 /**
 162  * fls - find last bit set
 163  * @x: the word to search
 164  *
 165  * This is defined the same way as ffs:
 166  * - return 32..1 to indicate bit 31..0 most significant bit set
 167  * - return 0 to indicate no bits set
 168  */
 169 #define fls(x)                                          \
 170 ({                                                      \
 171         int bit;                                        \
 172                                                         \
 173         asm("   subcc   %1,gr0,gr0,icc0         \n"     \
 174             "   ckne    icc0,cc4                \n"     \
 175             "   cscan.p %1,gr0,%0       ,cc4,#1 \n"     \
 176             "   csub    %0,%0,%0        ,cc4,#0 \n"     \
 177             "   csub    %2,%0,%0        ,cc4,#1 \n"     \
 178             : "=&r"(bit)                                \
 179             : "r"(x), "r"(32)                           \
 180             : "icc0", "cc4"                             \
 181             );                                          \
 182                                                         \
 183         bit;                                            \
 184 })
 185
 186 /**
 187  * fls64 - find last bit set in a 64-bit value
 188  * @n: the value to search
 189  *
 190  * This is defined the same way as ffs:
 191  * - return 64..1 to indicate bit 63..0 most significant bit set
 192  * - return 0 to indicate no bits set
 193  */
 194 static inline __attribute__((const))
 195 int fls64(u64 n)
 196 {
 197         union {
 198                 u64 ll;
 199                 struct { u32 h, l; };
 200         } _;
 201         int bit, x, y;
 202
 203         _.ll = n;
 204
 205         asm("   subcc.p         %3,gr0,gr0,icc0         \n"
 206             "   subcc           %4,gr0,gr0,icc1         \n"
 207             "   ckne            icc0,cc4                \n"
 208             "   ckne            icc1,cc5                \n"
 209             "   norcr           cc4,cc5,cc6             \n"
 210             "   csub.p          %0,%0,%0        ,cc6,1  \n"
 211             "   orcr            cc5,cc4,cc4             \n"
 212             "   andcr           cc4,cc5,cc4             \n"
 213             "   cscan.p         %3,gr0,%0       ,cc4,0  \n"
 214             "   setlos          #64,%1                  \n"
 215             "   cscan.p         %4,gr0,%0       ,cc4,1  \n"
 216             "   setlos          #32,%2                  \n"
 217             "   csub.p          %1,%0,%0        ,cc4,0  \n"
 218             "   csub            %2,%0,%0        ,cc4,1  \n"
 219             : "=&r"(bit), "=r"(x), "=r"(y)
 220             : "0r"(_.h), "r"(_.l)
 221             : "icc0", "icc1", "cc4", "cc5", "cc6"
 222             );
 223         return bit;
 224
 225 }
 226
 227 /**
 228  * ffs - find first bit set
 229  * @x: the word to search
 230  *
 231  * - return 32..1 to indicate bit 31..0 most least significant bit set
 232  * - return 0 to indicate no bits set
 233  */
 234 static inline __attribute__((const))
 235 int ffs(int x)
 236 {
 237         /* Note: (x & -x) gives us a mask that is the least significant
 238          * (rightmost) 1-bit of the value in x.
 239          */
 240         return fls(x & -x);
 241 }
 242
 243 /**
 244  * __ffs - find first bit set
 245  * @x: the word to search
 246  *
 247  * - return 31..0 to indicate bit 31..0 most least significant bit set
 248  * - if no bits are set in x, the result is undefined
 249  */
 250 static inline __attribute__((const))
 251 int __ffs(unsigned long x)
 252 {
 253         int bit;
 254         asm("scan %1,gr0,%0" : "=r"(bit) : "r"(x & -x));
 255         return 31 - bit;
 256 }
 257
 258 /**
 259  * __fls - find last (most-significant) set bit in a long word
 260  * @word: the word to search
 261  *
 262  * Undefined if no set bit exists, so code should check against 0 first.
 263  */
 264 static inline unsigned long __fls(unsigned long word)
 265 {
 266         unsigned long bit;
 267         asm("scan %1,gr0,%0" : "=r"(bit) : "r"(word));
 268         return bit;
 269 }
 270
 271 /*
 272  * special slimline version of fls() for calculating ilog2_u32()
 273  * - note: no protection against n == 0
 274  */
 275 #define ARCH_HAS_ILOG2_U32
 276 static inline __attribute__((const))
 277 int __ilog2_u32(u32 n)
 278 {
 279         int bit;
 280         asm("scan %1,gr0,%0" : "=r"(bit) : "r"(n));
 281         return 31 - bit;
 282 }
 283
 284 /*
 285  * special slimline version of fls64() for calculating ilog2_u64()
 286  * - note: no protection against n == 0
 287  */
 288 #define ARCH_HAS_ILOG2_U64
 289 static inline __attribute__((const))
 290 int __ilog2_u64(u64 n)
 291 {
 292         union {
 293                 u64 ll;
 294                 struct { u32 h, l; };
 295         } _;
 296         int bit, x, y;
 297
 298         _.ll = n;
 299
 300         asm("   subcc           %3,gr0,gr0,icc0         \n"
 301             "   ckeq            icc0,cc4                \n"
 302             "   cscan.p         %3,gr0,%0       ,cc4,0  \n"
 303             "   setlos          #63,%1                  \n"
 304             "   cscan.p         %4,gr0,%0       ,cc4,1  \n"
 305             "   setlos          #31,%2                  \n"
 306             "   csub.p          %1,%0,%0        ,cc4,0  \n"
 307             "   csub            %2,%0,%0        ,cc4,1  \n"
 308             : "=&r"(bit), "=r"(x), "=r"(y)
 309             : "0r"(_.h), "r"(_.l)
 310             : "icc0", "cc4"
 311             );
 312         return bit;
 313 }
 314
 315 #include <asm-generic/bitops/sched.h>
 316 #include <asm-generic/bitops/hweight.h>
 317 #include <asm-generic/bitops/lock.h>
 318
 319 #include <asm-generic/bitops/le.h>
 320
 321 #include <asm-generic/bitops/ext2-atomic-setbit.h>
 322
 323 #endif /* __KERNEL__ */
 324
 325 #endif /* _ASM_BITOPS_H */