cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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dvb_math.h (1811B)

      1/*
      2 * dvb-math provides some complex fixed-point math
      3 * operations shared between the dvb related stuff
      4 *
      5 * Copyright (C) 2006 Christoph Pfister (christophpfister@gmail.com)
      6 *
      7 * This library is free software; you can redistribute it and/or modify
      8 * it under the terms of the GNU Lesser General Public License as
      9 * published by the Free Software Foundation; either version 2.1 of
     10 * the License, or (at your option) any later version.
     11 *
     12 * This program is distributed in the hope that it will be useful,
     13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
     14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
     15 * GNU Lesser General Public License for more details.
     16 */
     17
     18#ifndef __DVB_MATH_H
     19#define __DVB_MATH_H
     20
     21#include <linux/types.h>
     22
     23/**
     24 * intlog2 - computes log2 of a value; the result is shifted left by 24 bits
     25 *
     26 * @value: The value (must be != 0)
     27 *
     28 * to use rational values you can use the following method:
     29 *
     30 *   intlog2(value) = intlog2(value * 2^x) - x * 2^24
     31 *
     32 * Some usecase examples:
     33 *
     34 *	intlog2(8) will give 3 << 24 = 3 * 2^24
     35 *
     36 *	intlog2(9) will give 3 << 24 + ... = 3.16... * 2^24
     37 *
     38 *	intlog2(1.5) = intlog2(3) - 2^24 = 0.584... * 2^24
     39 *
     40 *
     41 * return: log2(value) * 2^24
     42 */
     43extern unsigned int intlog2(u32 value);
     44
     45/**
     46 * intlog10 - computes log10 of a value; the result is shifted left by 24 bits
     47 *
     48 * @value: The value (must be != 0)
     49 *
     50 * to use rational values you can use the following method:
     51 *
     52 *   intlog10(value) = intlog10(value * 10^x) - x * 2^24
     53 *
     54 * An usecase example:
     55 *
     56 *	intlog10(1000) will give 3 << 24 = 3 * 2^24
     57 *
     58 *   due to the implementation intlog10(1000) might be not exactly 3 * 2^24
     59 *
     60 * look at intlog2 for similar examples
     61 *
     62 * return: log10(value) * 2^24
     63 */
     64extern unsigned int intlog10(u32 value);
     65
     66#endif