diff options
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/include/asm/bitops.h | 114 |
1 files changed, 76 insertions, 38 deletions
diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h index 49df8c4c9d25..bac4a960b24c 100644 --- a/arch/mips/include/asm/bitops.h +++ b/arch/mips/include/asm/bitops.h @@ -558,39 +558,67 @@ static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long * __clear_bit(nr, addr); } -#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64) - /* * Return the bit position (0..63) of the most significant 1 bit in a word * Returns -1 if no 1 bit exists */ -static inline unsigned long __fls(unsigned long x) +static inline unsigned long __fls(unsigned long word) { - int lz; + int num; - if (sizeof(x) == 4) { + if (BITS_PER_LONG == 32 && + __builtin_constant_p(cpu_has_mips_r) && cpu_has_mips_r) { __asm__( " .set push \n" " .set mips32 \n" " clz %0, %1 \n" " .set pop \n" - : "=r" (lz) - : "r" (x)); + : "=r" (num) + : "r" (word)); - return 31 - lz; + return 31 - num; } - BUG_ON(sizeof(x) != 8); + if (BITS_PER_LONG == 64 && + __builtin_constant_p(cpu_has_mips64) && cpu_has_mips64) { + __asm__( + " .set push \n" + " .set mips64 \n" + " dclz %0, %1 \n" + " .set pop \n" + : "=r" (num) + : "r" (word)); - __asm__( - " .set push \n" - " .set mips64 \n" - " dclz %0, %1 \n" - " .set pop \n" - : "=r" (lz) - : "r" (x)); + return 63 - num; + } + + num = BITS_PER_LONG - 1; - return 63 - lz; +#if BITS_PER_LONG == 64 + if (!(word & (~0ul << 32))) { + num -= 32; + word <<= 32; + } +#endif + if (!(word & (~0ul << (BITS_PER_LONG-16)))) { + num -= 16; + word <<= 16; + } + if (!(word & (~0ul << (BITS_PER_LONG-8)))) { + num -= 8; + word <<= 8; + } + if (!(word & (~0ul << (BITS_PER_LONG-4)))) { + num -= 4; + word <<= 4; + } + if (!(word & (~0ul << (BITS_PER_LONG-2)))) { + num -= 2; + word <<= 2; + } + if (!(word & (~0ul << (BITS_PER_LONG-1)))) + num -= 1; + return num; } /* @@ -612,23 +640,43 @@ static inline unsigned long __ffs(unsigned long word) * This is defined the same way as ffs. * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. */ -static inline int fls(int word) +static inline int fls(int x) { - __asm__("clz %0, %1" : "=r" (word) : "r" (word)); + int r; - return 32 - word; -} + if (__builtin_constant_p(cpu_has_mips_r) && cpu_has_mips_r) { + __asm__("clz %0, %1" : "=r" (x) : "r" (x)); -#if defined(CONFIG_64BIT) && defined(CONFIG_CPU_MIPS64) -static inline int fls64(__u64 word) -{ - __asm__("dclz %0, %1" : "=r" (word) : "r" (word)); + return 32 - x; + } - return 64 - word; + r = 32; + if (!x) + return 0; + if (!(x & 0xffff0000u)) { + x <<= 16; + r -= 16; + } + if (!(x & 0xff000000u)) { + x <<= 8; + r -= 8; + } + if (!(x & 0xf0000000u)) { + x <<= 4; + r -= 4; + } + if (!(x & 0xc0000000u)) { + x <<= 2; + r -= 2; + } + if (!(x & 0x80000000u)) { + x <<= 1; + r -= 1; + } + return r; } -#else + #include <asm-generic/bitops/fls64.h> -#endif /* * ffs - find first bit set. @@ -646,16 +694,6 @@ static inline int ffs(int word) return fls(word & -word); } -#else - -#include <asm-generic/bitops/__ffs.h> -#include <asm-generic/bitops/__fls.h> -#include <asm-generic/bitops/ffs.h> -#include <asm-generic/bitops/fls.h> -#include <asm-generic/bitops/fls64.h> - -#endif /*defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64) */ - #include <asm-generic/bitops/ffz.h> #include <asm-generic/bitops/find.h> |