1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright 2023 Advanced Micro Devices, Inc. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a 6 * copy of this software and associated documentation files (the "Software"), 7 * to deal in the Software without restriction, including without limitation 8 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 9 * and/or sell copies of the Software, and to permit persons to whom the 10 * Software is furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice and this permission notice shall be included in 13 * all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 21 * OTHER DEALINGS IN THE SOFTWARE. 22 * 23 * Authors: AMD 24 * 25 */ 26 #include "dm_services.h" 27 #include "bw_fixed.h" 28 29 #define MAX_I64 \ 30 ((int64_t)((1ULL << 63) - 1)) 31 32 #define MIN_I64 \ 33 (-MAX_I64 - 1) 34 35 #define FRACTIONAL_PART_MASK \ 36 ((1ULL << BW_FIXED_BITS_PER_FRACTIONAL_PART) - 1) 37 38 #define GET_FRACTIONAL_PART(x) \ 39 (FRACTIONAL_PART_MASK & (x)) 40 41 static uint64_t abs_i64(int64_t arg) 42 { 43 if (arg >= 0) 44 return (uint64_t)(arg); 45 else 46 return (uint64_t)(-arg); 47 } 48 49 struct bw_fixed bw_int_to_fixed_nonconst(int64_t value) 50 { 51 struct bw_fixed res; 52 53 ASSERT(value < BW_FIXED_MAX_I32 && value > BW_FIXED_MIN_I32); 54 res.value = value << BW_FIXED_BITS_PER_FRACTIONAL_PART; 55 return res; 56 } 57 58 struct bw_fixed bw_frc_to_fixed(int64_t numerator, int64_t denominator) 59 { 60 struct bw_fixed res; 61 bool arg1_negative = numerator < 0; 62 bool arg2_negative = denominator < 0; 63 uint64_t arg1_value; 64 uint64_t arg2_value; 65 uint64_t remainder; 66 67 /* determine integer part */ 68 uint64_t res_value; 69 70 ASSERT(denominator != 0); 71 72 arg1_value = abs_i64(numerator); 73 arg2_value = abs_i64(denominator); 74 res_value = div64_u64_rem(arg1_value, arg2_value, &remainder); 75 76 ASSERT(res_value <= BW_FIXED_MAX_I32); 77 78 /* determine fractional part */ 79 { 80 uint32_t i = BW_FIXED_BITS_PER_FRACTIONAL_PART; 81 82 do { 83 remainder <<= 1; 84 85 res_value <<= 1; 86 87 if (remainder >= arg2_value) { 88 res_value |= 1; 89 remainder -= arg2_value; 90 } 91 } while (--i != 0); 92 } 93 94 /* round up LSB */ 95 { 96 uint64_t summand = (remainder << 1) >= arg2_value; 97 98 ASSERT(res_value <= MAX_I64 - summand); 99 100 res_value += summand; 101 } 102 103 res.value = (int64_t)(res_value); 104 105 if (arg1_negative ^ arg2_negative) 106 res.value = -res.value; 107 return res; 108 } 109 110 struct bw_fixed bw_floor2(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(const struct bw_fixed arg, 123 const struct bw_fixed significance) 124 { 125 struct bw_fixed result; 126 int64_t multiplicand; 127 128 multiplicand = div64_s64(arg.value, abs_i64(significance.value)); 129 result.value = abs_i64(significance.value) * multiplicand; 130 if (abs_i64(result.value) < abs_i64(arg.value)) { 131 if (arg.value < 0) 132 result.value -= abs_i64(significance.value); 133 else 134 result.value += abs_i64(significance.value); 135 } 136 return result; 137 } 138 139 struct bw_fixed bw_mul(const struct bw_fixed arg1, const struct bw_fixed arg2) 140 { 141 struct bw_fixed res; 142 143 bool arg1_negative = arg1.value < 0; 144 bool arg2_negative = arg2.value < 0; 145 146 uint64_t arg1_value = abs_i64(arg1.value); 147 uint64_t arg2_value = abs_i64(arg2.value); 148 149 uint64_t arg1_int = BW_FIXED_GET_INTEGER_PART(arg1_value); 150 uint64_t arg2_int = BW_FIXED_GET_INTEGER_PART(arg2_value); 151 152 uint64_t arg1_fra = GET_FRACTIONAL_PART(arg1_value); 153 uint64_t arg2_fra = GET_FRACTIONAL_PART(arg2_value); 154 155 uint64_t tmp; 156 157 res.value = arg1_int * arg2_int; 158 159 ASSERT(res.value <= BW_FIXED_MAX_I32); 160 161 res.value <<= BW_FIXED_BITS_PER_FRACTIONAL_PART; 162 163 tmp = arg1_int * arg2_fra; 164 165 ASSERT(tmp <= (uint64_t)(MAX_I64 - res.value)); 166 167 res.value += tmp; 168 169 tmp = arg2_int * arg1_fra; 170 171 ASSERT(tmp <= (uint64_t)(MAX_I64 - res.value)); 172 173 res.value += tmp; 174 175 tmp = arg1_fra * arg2_fra; 176 177 tmp = (tmp >> BW_FIXED_BITS_PER_FRACTIONAL_PART) + 178 (tmp >= (uint64_t)(bw_frc_to_fixed(1, 2).value)); 179 180 ASSERT(tmp <= (uint64_t)(MAX_I64 - res.value)); 181 182 res.value += tmp; 183 184 if (arg1_negative ^ arg2_negative) 185 res.value = -res.value; 186 return res; 187 } 188 189