From: Kuo-Jung Su <dant...@faraday-tech.com> Signed-off-by: Kuo-Jung Su <dant...@faraday-tech.com> --- include/qemu/bitops.h | 59 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 58 insertions(+), 1 deletion(-)
diff --git a/include/qemu/bitops.h b/include/qemu/bitops.h index affcc96..64cbb04 100644 --- a/include/qemu/bitops.h +++ b/include/qemu/bitops.h @@ -3,7 +3,8 @@ * * Copyright (C) 2010 Corentin Chary <corentin.ch...@gmail.com> * - * Mostly inspired by (stolen from) linux/bitmap.h and linux/bitops.h + * Mostly inspired by (stolen from) linux/bitmap.h, linux/bitops.h + * and linux/bitrev.h * * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. * See the COPYING.LIB file in the top-level directory. @@ -273,4 +274,60 @@ static inline uint64_t deposit64(uint64_t value, int start, int length, return (value & ~mask) | ((fieldval << start) & mask); } +/** + * bitrev8: + * @value: the value to reverse bit ordering from + * + * Reverse the 8 bit input @value + * + * Returns: the input @value with reversed bit ordering + */ +static inline uint8_t bitrev8(uint8_t value) +{ + value = (value & 0xF0) >> 4 | (value & 0x0F) << 4; + value = (value & 0xCC) >> 2 | (value & 0x33) << 2; + value = (value & 0xAA) >> 1 | (value & 0x55) << 1; + return value; +} + +/** + * bitrev16: + * @value: the value to reverse bit ordering from + * + * Reverse the 16 bit input @value + * + * Returns: the input @value with reversed bit ordering + */ +static inline uint16_t bitrev16(uint16_t value) +{ + return (bitrev8(value & 0xff) << 8) | bitrev8(value >> 8); +} + +/** + * bitrev32: + * @value: the value to reverse bit ordering from + * + * Reverse the 32 bit input @value + * + * Returns: the input @value with reversed bit ordering + */ +static inline uint32_t bitrev32(uint32_t value) +{ + return (bitrev16(value & 0xffff) << 16) | bitrev16(value >> 16); +} + +/** + * bitrev64: + * @value: the value to reverse bit ordering from + * + * Reverse the 64 bit input @value + * + * Returns: the input @value with reversed bit ordering + */ +static inline uint64_t bitrev64(uint64_t value) +{ + return ((uint64_t)bitrev32(value & 0xffffffffULL) << 32) + | (uint64_t)bitrev32(value >> 32); +} + #endif -- 1.7.9.5