1 /* 2 * include/asm-xtensa/bitops.h 3 * 4 * Atomic operations that C can't guarantee us.Useful for resource counting etc. 5 * 6 * This file is subject to the terms and conditions of the GNU General Public 7 * License. See the file "COPYING" in the main directory of this archive 8 * for more details. 9 * 10 * Copyright (C) 2001 - 2007 Tensilica Inc. 11 */ 12 13 #ifndef _XTENSA_BITOPS_H 14 #define _XTENSA_BITOPS_H 15 16 #ifndef _LINUX_BITOPS_H 17 #error only <linux/bitops.h> can be included directly 18 #endif 19 20 #include <asm/processor.h> 21 #include <asm/byteorder.h> 22 #include <asm/barrier.h> 23 24 #include <asm-generic/bitops/non-atomic.h> 25 26 #if XCHAL_HAVE_NSA 27 28 static inline unsigned long __cntlz (unsigned long x) 29 { 30 int lz; 31 asm ("nsau %0, %1" : "=r" (lz) : "r" (x)); 32 return lz; 33 } 34 35 /* 36 * ffz: Find first zero in word. Undefined if no zero exists. 37 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). 38 */ 39 40 static inline int ffz(unsigned long x) 41 { 42 return 31 - __cntlz(~x & -~x); 43 } 44 45 /* 46 * __ffs: Find first bit set in word. Return 0 for bit 0 47 */ 48 49 static inline unsigned long __ffs(unsigned long x) 50 { 51 return 31 - __cntlz(x & -x); 52 } 53 54 /* 55 * ffs: Find first bit set in word. This is defined the same way as 56 * the libc and compiler builtin ffs routines, therefore 57 * differs in spirit from the above ffz (man ffs). 58 */ 59 60 static inline int ffs(unsigned long x) 61 { 62 return 32 - __cntlz(x & -x); 63 } 64 65 /* 66 * fls: Find last (most-significant) bit set in word. 67 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. 68 */ 69 70 static inline int fls (unsigned int x) 71 { 72 return 32 - __cntlz(x); 73 } 74 75 /** 76 * __fls - find last (most-significant) set bit in a long word 77 * @word: the word to search 78 * 79 * Undefined if no set bit exists, so code should check against 0 first. 80 */ 81 static inline unsigned long __fls(unsigned long word) 82 { 83 return 31 - __cntlz(word); 84 } 85 #else 86 87 /* Use the generic implementation if we don't have the nsa/nsau instructions. */ 88 89 # include <asm-generic/bitops/ffs.h> 90 # include <asm-generic/bitops/__ffs.h> 91 # include <asm-generic/bitops/ffz.h> 92 # include <asm-generic/bitops/fls.h> 93 # include <asm-generic/bitops/__fls.h> 94 95 #endif 96 97 #include <asm-generic/bitops/fls64.h> 98 99 #if XCHAL_HAVE_EXCLUSIVE 100 101 #define BIT_OP(op, insn, inv) \ 102 static inline void op##_bit(unsigned int bit, volatile unsigned long *p)\ 103 { \ 104 unsigned long tmp; \ 105 unsigned long mask = 1UL << (bit & 31); \ 106 \ 107 p += bit >> 5; \ 108 \ 109 __asm__ __volatile__( \ 110 "1: l32ex %[tmp], %[addr]\n" \ 111 " "insn" %[tmp], %[tmp], %[mask]\n" \ 112 " s32ex %[tmp], %[addr]\n" \ 113 " getex %[tmp]\n" \ 114 " beqz %[tmp], 1b\n" \ 115 : [tmp] "=&a" (tmp) \ 116 : [mask] "a" (inv mask), [addr] "a" (p) \ 117 : "memory"); \ 118 } 119 120 #define TEST_AND_BIT_OP(op, insn, inv) \ 121 static inline int \ 122 test_and_##op##_bit(unsigned int bit, volatile unsigned long *p) \ 123 { \ 124 unsigned long tmp, value; \ 125 unsigned long mask = 1UL << (bit & 31); \ 126 \ 127 p += bit >> 5; \ 128 \ 129 __asm__ __volatile__( \ 130 "1: l32ex %[value], %[addr]\n" \ 131 " "insn" %[tmp], %[value], %[mask]\n" \ 132 " s32ex %[tmp], %[addr]\n" \ 133 " getex %[tmp]\n" \ 134 " beqz %[tmp], 1b\n" \ 135 : [tmp] "=&a" (tmp), [value] "=&a" (value) \ 136 : [mask] "a" (inv mask), [addr] "a" (p) \ 137 : "memory"); \ 138 \ 139 return value & mask; \ 140 } 141 142 #elif XCHAL_HAVE_S32C1I 143 144 #define BIT_OP(op, insn, inv) \ 145 static inline void op##_bit(unsigned int bit, volatile unsigned long *p)\ 146 { \ 147 unsigned long tmp, value; \ 148 unsigned long mask = 1UL << (bit & 31); \ 149 \ 150 p += bit >> 5; \ 151 \ 152 __asm__ __volatile__( \ 153 "1: l32i %[value], %[mem]\n" \ 154 " wsr %[value], scompare1\n" \ 155 " "insn" %[tmp], %[value], %[mask]\n" \ 156 " s32c1i %[tmp], %[mem]\n" \ 157 " bne %[tmp], %[value], 1b\n" \ 158 : [tmp] "=&a" (tmp), [value] "=&a" (value), \ 159 [mem] "+m" (*p) \ 160 : [mask] "a" (inv mask) \ 161 : "memory"); \ 162 } 163 164 #define TEST_AND_BIT_OP(op, insn, inv) \ 165 static inline int \ 166 test_and_##op##_bit(unsigned int bit, volatile unsigned long *p) \ 167 { \ 168 unsigned long tmp, value; \ 169 unsigned long mask = 1UL << (bit & 31); \ 170 \ 171 p += bit >> 5; \ 172 \ 173 __asm__ __volatile__( \ 174 "1: l32i %[value], %[mem]\n" \ 175 " wsr %[value], scompare1\n" \ 176 " "insn" %[tmp], %[value], %[mask]\n" \ 177 " s32c1i %[tmp], %[mem]\n" \ 178 " bne %[tmp], %[value], 1b\n" \ 179 : [tmp] "=&a" (tmp), [value] "=&a" (value), \ 180 [mem] "+m" (*p) \ 181 : [mask] "a" (inv mask) \ 182 : "memory"); \ 183 \ 184 return tmp & mask; \ 185 } 186 187 #else 188 189 #define BIT_OP(op, insn, inv) 190 #define TEST_AND_BIT_OP(op, insn, inv) 191 192 #include <asm-generic/bitops/atomic.h> 193 194 #endif /* XCHAL_HAVE_S32C1I */ 195 196 #define BIT_OPS(op, insn, inv) \ 197 BIT_OP(op, insn, inv) \ 198 TEST_AND_BIT_OP(op, insn, inv) 199 200 BIT_OPS(set, "or", ) 201 BIT_OPS(clear, "and", ~) 202 BIT_OPS(change, "xor", ) 203 204 #undef BIT_OPS 205 #undef BIT_OP 206 #undef TEST_AND_BIT_OP 207 208 #include <asm-generic/bitops/le.h> 209 210 #include <asm-generic/bitops/ext2-atomic-setbit.h> 211 212 #include <asm-generic/bitops/hweight.h> 213 #include <asm-generic/bitops/lock.h> 214 #include <asm-generic/bitops/sched.h> 215 216 #endif /* _XTENSA_BITOPS_H */ 217