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(arg: numerator); |
73 | arg2_value = abs_i64(arg: denominator); |
74 | res_value = div64_u64_rem(dividend: arg1_value, divisor: arg2_value, remainder: &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(dividend: arg.value, divisor: abs_i64(arg: significance.value)); |
117 | result.value = abs_i64(arg: 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(dividend: arg.value, divisor: abs_i64(arg: significance.value)); |
129 | result.value = abs_i64(arg: significance.value) * multiplicand; |
130 | if (abs_i64(arg: result.value) < abs_i64(arg: arg.value)) { |
131 | if (arg.value < 0) |
132 | result.value -= abs_i64(arg: significance.value); |
133 | else |
134 | result.value += abs_i64(arg: 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(arg: arg1.value); |
147 | uint64_t arg2_value = abs_i64(arg: 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(numerator: 1, denominator: 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 | |