1 /* $NetBSD: amdgpu_dcn_calc_math.c,v 1.2 2021/12/18 23:45:01 riastradh Exp $ */
2
3 /*
4 * Copyright 2017 Advanced Micro Devices, Inc.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 *
24 * Authors: AMD
25 *
26 */
27
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: amdgpu_dcn_calc_math.c,v 1.2 2021/12/18 23:45:01 riastradh Exp $");
30
31 #include "dcn_calc_math.h"
32
33 #define isNaN(number) ((number) != (number))
34
35 /*
36 * NOTE:
37 * This file is gcc-parseable HW gospel, coming straight from HW engineers.
38 *
39 * It doesn't adhere to Linux kernel style and sometimes will do things in odd
40 * ways. Unless there is something clearly wrong with it the code should
41 * remain as-is as it provides us with a guarantee from HW that it is correct.
42 */
43
dcn_bw_mod(const float arg1,const float arg2)44 float dcn_bw_mod(const float arg1, const float arg2)
45 {
46 if (isNaN(arg1))
47 return arg2;
48 if (isNaN(arg2))
49 return arg1;
50 return arg1 - arg1 * ((int) (arg1 / arg2));
51 }
52
dcn_bw_min2(const float arg1,const float arg2)53 float dcn_bw_min2(const float arg1, const float arg2)
54 {
55 if (isNaN(arg1))
56 return arg2;
57 if (isNaN(arg2))
58 return arg1;
59 return arg1 < arg2 ? arg1 : arg2;
60 }
61
dcn_bw_max(const unsigned int arg1,const unsigned int arg2)62 unsigned int dcn_bw_max(const unsigned int arg1, const unsigned int arg2)
63 {
64 return arg1 > arg2 ? arg1 : arg2;
65 }
dcn_bw_max2(const float arg1,const float arg2)66 float dcn_bw_max2(const float arg1, const float arg2)
67 {
68 if (isNaN(arg1))
69 return arg2;
70 if (isNaN(arg2))
71 return arg1;
72 return arg1 > arg2 ? arg1 : arg2;
73 }
74
dcn_bw_floor2(const float arg,const float significance)75 float dcn_bw_floor2(const float arg, const float significance)
76 {
77 if (significance == 0)
78 return 0;
79 return ((int) (arg / significance)) * significance;
80 }
dcn_bw_floor(const float arg)81 float dcn_bw_floor(const float arg)
82 {
83 return ((int) (arg));
84 }
85
dcn_bw_ceil(const float arg)86 float dcn_bw_ceil(const float arg)
87 {
88 float flr = dcn_bw_floor2(arg, 1);
89
90 return flr + 0.00001 >= arg ? arg : flr + 1;
91 }
92
dcn_bw_ceil2(const float arg,const float significance)93 float dcn_bw_ceil2(const float arg, const float significance)
94 {
95 float flr = dcn_bw_floor2(arg, significance);
96 if (significance == 0)
97 return 0;
98 return flr + 0.00001 >= arg ? arg : flr + significance;
99 }
100
dcn_bw_max3(float v1,float v2,float v3)101 float dcn_bw_max3(float v1, float v2, float v3)
102 {
103 return v3 > dcn_bw_max2(v1, v2) ? v3 : dcn_bw_max2(v1, v2);
104 }
105
dcn_bw_max5(float v1,float v2,float v3,float v4,float v5)106 float dcn_bw_max5(float v1, float v2, float v3, float v4, float v5)
107 {
108 return dcn_bw_max3(v1, v2, v3) > dcn_bw_max2(v4, v5) ? dcn_bw_max3(v1, v2, v3) : dcn_bw_max2(v4, v5);
109 }
110
dcn_bw_pow(float a,float exp)111 float dcn_bw_pow(float a, float exp)
112 {
113 float temp;
114 /*ASSERT(exp == (int)exp);*/
115 if ((int)exp == 0)
116 return 1;
117 temp = dcn_bw_pow(a, (int)(exp / 2));
118 if (((int)exp % 2) == 0) {
119 return temp * temp;
120 } else {
121 if ((int)exp > 0)
122 return a * temp * temp;
123 else
124 return (temp * temp) / a;
125 }
126 }
127
dcn_bw_fabs(double a)128 double dcn_bw_fabs(double a)
129 {
130 if (a > 0)
131 return (a);
132 else
133 return (-a);
134 }
135
136
dcn_bw_log(float a,float b)137 float dcn_bw_log(float a, float b)
138 {
139 int * const exp_ptr = (int *)(&a);
140 int x = *exp_ptr;
141 const int log_2 = ((x >> 23) & 255) - 128;
142 x &= ~(255 << 23);
143 x += 127 << 23;
144 *exp_ptr = x;
145
146 a = ((-1.0f / 3) * a + 2) * a - 2.0f / 3;
147
148 if (b > 2.00001 || b < 1.99999)
149 return (a + log_2) / dcn_bw_log(b, 2);
150 else
151 return (a + log_2);
152 }
153