1 /* $NetBSD: fixed31_32.h,v 1.3 2021/12/19 10:59:02 riastradh Exp $ */ 2 3 /* 4 * Copyright 2012-15 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 #ifndef __DAL_FIXED31_32_H__ 29 #define __DAL_FIXED31_32_H__ 30 31 #include "os_types.h" 32 33 #ifndef LLONG_MAX 34 #define LLONG_MAX 9223372036854775807ll 35 #endif 36 #ifndef LLONG_MIN 37 #define LLONG_MIN (-LLONG_MAX - 1ll) 38 #endif 39 40 #define FIXED31_32_BITS_PER_FRACTIONAL_PART 32 41 #ifndef LLONG_MIN 42 #define LLONG_MIN (1LL<<63) 43 #endif 44 #ifndef LLONG_MAX 45 #define LLONG_MAX (-1LL>>1) 46 #endif 47 48 /* 49 * @brief 50 * Arithmetic operations on real numbers 51 * represented as fixed-point numbers. 52 * There are: 1 bit for sign, 53 * 31 bit for integer part, 54 * 32 bits for fractional part. 55 * 56 * @note 57 * Currently, overflows and underflows are asserted; 58 * no special result returned. 59 */ 60 61 struct fixed31_32 { 62 long long value; 63 }; 64 65 66 /* 67 * @brief 68 * Useful constants 69 */ 70 71 static const struct fixed31_32 dc_fixpt_zero = { 0 }; 72 static const struct fixed31_32 dc_fixpt_epsilon = { 1LL }; 73 static const struct fixed31_32 dc_fixpt_half = { 0x80000000LL }; 74 static const struct fixed31_32 dc_fixpt_one = { 0x100000000LL }; 75 76 static const struct fixed31_32 dc_fixpt_pi = { 13493037705LL }; 77 static const struct fixed31_32 dc_fixpt_two_pi = { 26986075409LL }; 78 static const struct fixed31_32 dc_fixpt_e = { 11674931555LL }; 79 static const struct fixed31_32 dc_fixpt_ln2 = { 2977044471LL }; 80 static const struct fixed31_32 dc_fixpt_ln2_div_2 = { 1488522236LL }; 81 82 /* 83 * @brief 84 * Initialization routines 85 */ 86 87 /* 88 * @brief 89 * result = numerator / denominator 90 */ 91 struct fixed31_32 dc_fixpt_from_fraction(long long numerator, long long denominator); 92 93 /* 94 * @brief 95 * result = arg 96 */ 97 static inline struct fixed31_32 dc_fixpt_from_int(int arg) 98 { 99 struct fixed31_32 res; 100 101 res.value = (long long) arg << FIXED31_32_BITS_PER_FRACTIONAL_PART; 102 103 return res; 104 } 105 106 /* 107 * @brief 108 * Unary operators 109 */ 110 111 /* 112 * @brief 113 * result = -arg 114 */ 115 static inline struct fixed31_32 dc_fixpt_neg(struct fixed31_32 arg) 116 { 117 struct fixed31_32 res; 118 119 res.value = -arg.value; 120 121 return res; 122 } 123 124 /* 125 * @brief 126 * result = abs(arg) := (arg >= 0) ? arg : -arg 127 */ 128 static inline struct fixed31_32 dc_fixpt_abs(struct fixed31_32 arg) 129 { 130 if (arg.value < 0) 131 return dc_fixpt_neg(arg); 132 else 133 return arg; 134 } 135 136 /* 137 * @brief 138 * Binary relational operators 139 */ 140 141 /* 142 * @brief 143 * result = arg1 < arg2 144 */ 145 static inline bool dc_fixpt_lt(struct fixed31_32 arg1, struct fixed31_32 arg2) 146 { 147 return arg1.value < arg2.value; 148 } 149 150 /* 151 * @brief 152 * result = arg1 <= arg2 153 */ 154 static inline bool dc_fixpt_le(struct fixed31_32 arg1, struct fixed31_32 arg2) 155 { 156 return arg1.value <= arg2.value; 157 } 158 159 /* 160 * @brief 161 * result = arg1 == arg2 162 */ 163 static inline bool dc_fixpt_eq(struct fixed31_32 arg1, struct fixed31_32 arg2) 164 { 165 return arg1.value == arg2.value; 166 } 167 168 /* 169 * @brief 170 * result = min(arg1, arg2) := (arg1 <= arg2) ? arg1 : arg2 171 */ 172 static inline struct fixed31_32 dc_fixpt_min(struct fixed31_32 arg1, struct fixed31_32 arg2) 173 { 174 if (arg1.value <= arg2.value) 175 return arg1; 176 else 177 return arg2; 178 } 179 180 /* 181 * @brief 182 * result = max(arg1, arg2) := (arg1 <= arg2) ? arg2 : arg1 183 */ 184 static inline struct fixed31_32 dc_fixpt_max(struct fixed31_32 arg1, struct fixed31_32 arg2) 185 { 186 if (arg1.value <= arg2.value) 187 return arg2; 188 else 189 return arg1; 190 } 191 192 /* 193 * @brief 194 * | min_value, when arg <= min_value 195 * result = | arg, when min_value < arg < max_value 196 * | max_value, when arg >= max_value 197 */ 198 static inline struct fixed31_32 dc_fixpt_clamp( 199 struct fixed31_32 arg, 200 struct fixed31_32 min_value, 201 struct fixed31_32 max_value) 202 { 203 if (dc_fixpt_le(arg, min_value)) 204 return min_value; 205 else if (dc_fixpt_le(max_value, arg)) 206 return max_value; 207 else 208 return arg; 209 } 210 211 /* 212 * @brief 213 * Binary shift operators 214 */ 215 216 /* 217 * @brief 218 * result = arg << shift 219 */ 220 static inline struct fixed31_32 dc_fixpt_shl(struct fixed31_32 arg, unsigned char shift) 221 { 222 ASSERT(((arg.value >= 0) && (arg.value <= LLONG_MAX >> shift)) || 223 ((arg.value < 0) && (arg.value >= ~(LLONG_MAX >> shift)))); 224 225 arg.value = arg.value << shift; 226 227 return arg; 228 } 229 230 /* 231 * @brief 232 * result = arg >> shift 233 */ 234 static inline struct fixed31_32 dc_fixpt_shr(struct fixed31_32 arg, unsigned char shift) 235 { 236 bool negative = arg.value < 0; 237 238 if (negative) 239 arg.value = -arg.value; 240 arg.value = arg.value >> shift; 241 if (negative) 242 arg.value = -arg.value; 243 return arg; 244 } 245 246 /* 247 * @brief 248 * Binary additive operators 249 */ 250 251 /* 252 * @brief 253 * result = arg1 + arg2 254 */ 255 static inline struct fixed31_32 dc_fixpt_add(struct fixed31_32 arg1, struct fixed31_32 arg2) 256 { 257 struct fixed31_32 res; 258 259 ASSERT(((arg1.value >= 0) && (LLONG_MAX - arg1.value >= arg2.value)) || 260 ((arg1.value < 0) && (LLONG_MIN - arg1.value <= arg2.value))); 261 262 res.value = arg1.value + arg2.value; 263 264 return res; 265 } 266 267 /* 268 * @brief 269 * result = arg1 + arg2 270 */ 271 static inline struct fixed31_32 dc_fixpt_add_int(struct fixed31_32 arg1, int arg2) 272 { 273 return dc_fixpt_add(arg1, dc_fixpt_from_int(arg2)); 274 } 275 276 /* 277 * @brief 278 * result = arg1 - arg2 279 */ 280 static inline struct fixed31_32 dc_fixpt_sub(struct fixed31_32 arg1, struct fixed31_32 arg2) 281 { 282 struct fixed31_32 res; 283 284 ASSERT(((arg2.value >= 0) && (LLONG_MIN + arg2.value <= arg1.value)) || 285 ((arg2.value < 0) && (LLONG_MAX + arg2.value >= arg1.value))); 286 287 res.value = arg1.value - arg2.value; 288 289 return res; 290 } 291 292 /* 293 * @brief 294 * result = arg1 - arg2 295 */ 296 static inline struct fixed31_32 dc_fixpt_sub_int(struct fixed31_32 arg1, int arg2) 297 { 298 return dc_fixpt_sub(arg1, dc_fixpt_from_int(arg2)); 299 } 300 301 302 /* 303 * @brief 304 * Binary multiplicative operators 305 */ 306 307 /* 308 * @brief 309 * result = arg1 * arg2 310 */ 311 struct fixed31_32 dc_fixpt_mul(struct fixed31_32 arg1, struct fixed31_32 arg2); 312 313 314 /* 315 * @brief 316 * result = arg1 * arg2 317 */ 318 static inline struct fixed31_32 dc_fixpt_mul_int(struct fixed31_32 arg1, int arg2) 319 { 320 return dc_fixpt_mul(arg1, dc_fixpt_from_int(arg2)); 321 } 322 323 /* 324 * @brief 325 * result = square(arg) := arg * arg 326 */ 327 struct fixed31_32 dc_fixpt_sqr(struct fixed31_32 arg); 328 329 /* 330 * @brief 331 * result = arg1 / arg2 332 */ 333 static inline struct fixed31_32 dc_fixpt_div_int(struct fixed31_32 arg1, long long arg2) 334 { 335 return dc_fixpt_from_fraction(arg1.value, dc_fixpt_from_int(arg2).value); 336 } 337 338 /* 339 * @brief 340 * result = arg1 / arg2 341 */ 342 static inline struct fixed31_32 dc_fixpt_div(struct fixed31_32 arg1, struct fixed31_32 arg2) 343 { 344 return dc_fixpt_from_fraction(arg1.value, arg2.value); 345 } 346 347 /* 348 * @brief 349 * Reciprocal function 350 */ 351 352 /* 353 * @brief 354 * result = reciprocal(arg) := 1 / arg 355 * 356 * @note 357 * No special actions taken in case argument is zero. 358 */ 359 struct fixed31_32 dc_fixpt_recip(struct fixed31_32 arg); 360 361 /* 362 * @brief 363 * Trigonometric functions 364 */ 365 366 /* 367 * @brief 368 * result = sinc(arg) := sin(arg) / arg 369 * 370 * @note 371 * Argument specified in radians, 372 * internally it's normalized to [-2pi...2pi] range. 373 */ 374 struct fixed31_32 dc_fixpt_sinc(struct fixed31_32 arg); 375 376 /* 377 * @brief 378 * result = sin(arg) 379 * 380 * @note 381 * Argument specified in radians, 382 * internally it's normalized to [-2pi...2pi] range. 383 */ 384 struct fixed31_32 dc_fixpt_sin(struct fixed31_32 arg); 385 386 /* 387 * @brief 388 * result = cos(arg) 389 * 390 * @note 391 * Argument specified in radians 392 * and should be in [-2pi...2pi] range - 393 * passing arguments outside that range 394 * will cause incorrect result! 395 */ 396 struct fixed31_32 dc_fixpt_cos(struct fixed31_32 arg); 397 398 /* 399 * @brief 400 * Transcendent functions 401 */ 402 403 /* 404 * @brief 405 * result = exp(arg) 406 * 407 * @note 408 * Currently, function is verified for abs(arg) <= 1. 409 */ 410 struct fixed31_32 dc_fixpt_exp(struct fixed31_32 arg); 411 412 /* 413 * @brief 414 * result = log(arg) 415 * 416 * @note 417 * Currently, abs(arg) should be less than 1. 418 * No normalization is done. 419 * Currently, no special actions taken 420 * in case of invalid argument(s). Take care! 421 */ 422 struct fixed31_32 dc_fixpt_log(struct fixed31_32 arg); 423 424 /* 425 * @brief 426 * Power function 427 */ 428 429 /* 430 * @brief 431 * result = pow(arg1, arg2) 432 * 433 * @note 434 * Currently, abs(arg1) should be less than 1. Take care! 435 */ 436 static inline struct fixed31_32 dc_fixpt_pow(struct fixed31_32 arg1, struct fixed31_32 arg2) 437 { 438 return dc_fixpt_exp( 439 dc_fixpt_mul( 440 dc_fixpt_log(arg1), 441 arg2)); 442 } 443 444 /* 445 * @brief 446 * Rounding functions 447 */ 448 449 /* 450 * @brief 451 * result = floor(arg) := greatest integer lower than or equal to arg 452 */ 453 static inline int dc_fixpt_floor(struct fixed31_32 arg) 454 { 455 unsigned long long arg_value = arg.value > 0 ? arg.value : -arg.value; 456 457 if (arg.value >= 0) 458 return (int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART); 459 else 460 return -(int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART); 461 } 462 463 /* 464 * @brief 465 * result = round(arg) := integer nearest to arg 466 */ 467 static inline int dc_fixpt_round(struct fixed31_32 arg) 468 { 469 unsigned long long arg_value = arg.value > 0 ? arg.value : -arg.value; 470 471 const long long summand = dc_fixpt_half.value; 472 473 ASSERT(LLONG_MAX - (long long)arg_value >= summand); 474 475 arg_value += summand; 476 477 if (arg.value >= 0) 478 return (int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART); 479 else 480 return -(int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART); 481 } 482 483 /* 484 * @brief 485 * result = ceil(arg) := lowest integer greater than or equal to arg 486 */ 487 static inline int dc_fixpt_ceil(struct fixed31_32 arg) 488 { 489 unsigned long long arg_value = arg.value > 0 ? arg.value : -arg.value; 490 491 const long long summand = dc_fixpt_one.value - 492 dc_fixpt_epsilon.value; 493 494 ASSERT(LLONG_MAX - (long long)arg_value >= summand); 495 496 arg_value += summand; 497 498 if (arg.value >= 0) 499 return (int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART); 500 else 501 return -(int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART); 502 } 503 504 /* the following two function are used in scaler hw programming to convert fixed 505 * point value to format 2 bits from integer part and 19 bits from fractional 506 * part. The same applies for u0d19, 0 bits from integer part and 19 bits from 507 * fractional 508 */ 509 510 unsigned int dc_fixpt_u4d19(struct fixed31_32 arg); 511 512 unsigned int dc_fixpt_u3d19(struct fixed31_32 arg); 513 514 unsigned int dc_fixpt_u2d19(struct fixed31_32 arg); 515 516 unsigned int dc_fixpt_u0d19(struct fixed31_32 arg); 517 518 unsigned int dc_fixpt_clamp_u0d14(struct fixed31_32 arg); 519 520 unsigned int dc_fixpt_clamp_u0d10(struct fixed31_32 arg); 521 522 int dc_fixpt_s4d19(struct fixed31_32 arg); 523 524 static inline struct fixed31_32 dc_fixpt_truncate(struct fixed31_32 arg, unsigned int frac_bits) 525 { 526 bool negative = arg.value < 0; 527 528 if (frac_bits >= FIXED31_32_BITS_PER_FRACTIONAL_PART) { 529 ASSERT(frac_bits == FIXED31_32_BITS_PER_FRACTIONAL_PART); 530 return arg; 531 } 532 533 if (negative) 534 arg.value = -arg.value; 535 arg.value &= (~0ULL) << (FIXED31_32_BITS_PER_FRACTIONAL_PART - frac_bits); 536 if (negative) 537 arg.value = -arg.value; 538 return arg; 539 } 540 541 #endif 542