1 /* 2 * Copyright 2015 Advanced Micro Devices, Inc. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice shall be included in 12 * all copies or substantial portions of the Software. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 20 * OTHER DEALINGS IN THE SOFTWARE. 21 * 22 * Authors: AMD 23 * 24 */ 25 #include "dm_services.h" 26 #include "bw_fixed.h" 27 28 #define MAX_I64 \ 29 ((int64_t)((1ULL << 63) - 1)) 30 31 #define MIN_I64 \ 32 (-MAX_I64 - 1) 33 34 #define FRACTIONAL_PART_MASK \ 35 ((1ULL << BW_FIXED_BITS_PER_FRACTIONAL_PART) - 1) 36 37 #define GET_FRACTIONAL_PART(x) \ 38 (FRACTIONAL_PART_MASK & (x)) 39 40 static uint64_t abs_i64(int64_t arg) 41 { 42 if (arg >= 0) 43 return (uint64_t)(arg); 44 else 45 return (uint64_t)(-arg); 46 } 47 48 struct bw_fixed bw_int_to_fixed_nonconst(int64_t value) 49 { 50 struct bw_fixed res; 51 52 ASSERT(value < BW_FIXED_MAX_I32 && value > BW_FIXED_MIN_I32); 53 res.value = value << BW_FIXED_BITS_PER_FRACTIONAL_PART; 54 return res; 55 } 56 57 struct bw_fixed bw_frc_to_fixed(int64_t numerator, int64_t denominator) 58 { 59 struct bw_fixed res; 60 bool arg1_negative = numerator < 0; 61 bool arg2_negative = denominator < 0; 62 uint64_t arg1_value; 63 uint64_t arg2_value; 64 uint64_t remainder; 65 66 /* determine integer part */ 67 uint64_t res_value; 68 69 ASSERT(denominator != 0); 70 71 arg1_value = abs_i64(numerator); 72 arg2_value = abs_i64(denominator); 73 res_value = div64_u64_rem(arg1_value, arg2_value, &remainder); 74 75 ASSERT(res_value <= BW_FIXED_MAX_I32); 76 77 /* determine fractional part */ 78 { 79 uint32_t i = BW_FIXED_BITS_PER_FRACTIONAL_PART; 80 81 do { 82 remainder <<= 1; 83 84 res_value <<= 1; 85 86 if (remainder >= arg2_value) { 87 res_value |= 1; 88 remainder -= arg2_value; 89 } 90 } while (--i != 0); 91 } 92 93 /* round up LSB */ 94 { 95 uint64_t summand = (remainder << 1) >= arg2_value; 96 97 ASSERT(res_value <= MAX_I64 - summand); 98 99 res_value += summand; 100 } 101 102 res.value = (int64_t)(res_value); 103 104 if (arg1_negative ^ arg2_negative) 105 res.value = -res.value; 106 return res; 107 } 108 109 struct bw_fixed bw_floor2( 110 const struct bw_fixed arg, 111 const struct bw_fixed significance) 112 { 113 struct bw_fixed result; 114 int64_t multiplicand; 115 116 multiplicand = div64_s64(arg.value, abs_i64(significance.value)); 117 result.value = abs_i64(significance.value) * multiplicand; 118 ASSERT(abs_i64(result.value) <= abs_i64(arg.value)); 119 return result; 120 } 121 122 struct bw_fixed bw_ceil2( 123 const struct bw_fixed arg, 124 const struct bw_fixed significance) 125 { 126 struct bw_fixed result; 127 int64_t multiplicand; 128 129 multiplicand = div64_s64(arg.value, abs_i64(significance.value)); 130 result.value = abs_i64(significance.value) * multiplicand; 131 if (abs_i64(result.value) < abs_i64(arg.value)) { 132 if (arg.value < 0) 133 result.value -= abs_i64(significance.value); 134 else 135 result.value += abs_i64(significance.value); 136 } 137 return result; 138 } 139 140 struct bw_fixed bw_mul(const struct bw_fixed arg1, const struct bw_fixed arg2) 141 { 142 struct bw_fixed res; 143 144 bool arg1_negative = arg1.value < 0; 145 bool arg2_negative = arg2.value < 0; 146 147 uint64_t arg1_value = abs_i64(arg1.value); 148 uint64_t arg2_value = abs_i64(arg2.value); 149 150 uint64_t arg1_int = BW_FIXED_GET_INTEGER_PART(arg1_value); 151 uint64_t arg2_int = BW_FIXED_GET_INTEGER_PART(arg2_value); 152 153 uint64_t arg1_fra = GET_FRACTIONAL_PART(arg1_value); 154 uint64_t arg2_fra = GET_FRACTIONAL_PART(arg2_value); 155 156 uint64_t tmp; 157 158 res.value = arg1_int * arg2_int; 159 160 ASSERT(res.value <= BW_FIXED_MAX_I32); 161 162 res.value <<= BW_FIXED_BITS_PER_FRACTIONAL_PART; 163 164 tmp = arg1_int * arg2_fra; 165 166 ASSERT(tmp <= (uint64_t)(MAX_I64 - res.value)); 167 168 res.value += tmp; 169 170 tmp = arg2_int * arg1_fra; 171 172 ASSERT(tmp <= (uint64_t)(MAX_I64 - res.value)); 173 174 res.value += tmp; 175 176 tmp = arg1_fra * arg2_fra; 177 178 tmp = (tmp >> BW_FIXED_BITS_PER_FRACTIONAL_PART) + 179 (tmp >= (uint64_t)(bw_frc_to_fixed(1, 2).value)); 180 181 ASSERT(tmp <= (uint64_t)(MAX_I64 - res.value)); 182 183 res.value += tmp; 184 185 if (arg1_negative ^ arg2_negative) 186 res.value = -res.value; 187 return res; 188 } 189 190