drivers/gpu/drm/amd/display/include/fixed31_32.h

   1 /*
   2  * Copyright 2012-15 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
  26 #ifndef __DAL_FIXED31_32_H__
  27 #define __DAL_FIXED31_32_H__
  28
  29 #ifndef LLONG_MAX
  30 #define LLONG_MAX 9223372036854775807ll
  31 #endif
  32 #ifndef LLONG_MIN
  33 #define LLONG_MIN (-LLONG_MAX - 1ll)
  34 #endif
  35
  36 #define FIXED31_32_BITS_PER_FRACTIONAL_PART 32
  37 #ifndef LLONG_MIN
  38 #define LLONG_MIN (1LL<<63)
  39 #endif
  40 #ifndef LLONG_MAX
  41 #define LLONG_MAX (-1LL>>1)
  42 #endif
  43
  44 /*
  45  * @brief
  46  * Arithmetic operations on real numbers
  47  * represented as fixed-point numbers.
  48  * There are: 1 bit for sign,
  49  * 31 bit for integer part,
  50  * 32 bits for fractional part.
  51  *
  52  * @note
  53  * Currently, overflows and underflows are asserted;
  54  * no special result returned.
  55  */
  56
  57 struct fixed31_32 {
  58         long long value;
  59 };
  60
  61
  62 /*
  63  * @brief
  64  * Useful constants
  65  */
  66
  67 static const struct fixed31_32 dc_fixpt_zero = { 0 };
  68 static const struct fixed31_32 dc_fixpt_epsilon = { 1LL };
  69 static const struct fixed31_32 dc_fixpt_half = { 0x80000000LL };
  70 static const struct fixed31_32 dc_fixpt_one = { 0x100000000LL };
  71
  72 /*
  73  * @brief
  74  * Initialization routines
  75  */
  76
  77 /*
  78  * @brief
  79  * result = numerator / denominator
  80  */
  81 struct fixed31_32 dc_fixpt_from_fraction(long long numerator, long long denominator);
  82
  83 /*
  84  * @brief
  85  * result = arg
  86  */
  87 static inline struct fixed31_32 dc_fixpt_from_int(int arg)
  88 {
  89         struct fixed31_32 res;
  90
  91         res.value = (long long) arg << FIXED31_32_BITS_PER_FRACTIONAL_PART;
  92
  93         return res;
  94 }
  95
  96 /*
  97  * @brief
  98  * Unary operators
  99  */
 100
 101 /*
 102  * @brief
 103  * result = -arg
 104  */
 105 static inline struct fixed31_32 dc_fixpt_neg(struct fixed31_32 arg)
 106 {
 107         struct fixed31_32 res;
 108
 109         res.value = -arg.value;
 110
 111         return res;
 112 }
 113
 114 /*
 115  * @brief
 116  * result = abs(arg) := (arg >= 0) ? arg : -arg
 117  */
 118 static inline struct fixed31_32 dc_fixpt_abs(struct fixed31_32 arg)
 119 {
 120         if (arg.value < 0)
 121                 return dc_fixpt_neg(arg);
 122         else
 123                 return arg;
 124 }
 125
 126 /*
 127  * @brief
 128  * Binary relational operators
 129  */
 130
 131 /*
 132  * @brief
 133  * result = arg1 < arg2
 134  */
 135 static inline bool dc_fixpt_lt(struct fixed31_32 arg1, struct fixed31_32 arg2)
 136 {
 137         return arg1.value < arg2.value;
 138 }
 139
 140 /*
 141  * @brief
 142  * result = arg1 <= arg2
 143  */
 144 static inline bool dc_fixpt_le(struct fixed31_32 arg1, struct fixed31_32 arg2)
 145 {
 146         return arg1.value <= arg2.value;
 147 }
 148
 149 /*
 150  * @brief
 151  * result = arg1 == arg2
 152  */
 153 static inline bool dc_fixpt_eq(struct fixed31_32 arg1, struct fixed31_32 arg2)
 154 {
 155         return arg1.value == arg2.value;
 156 }
 157
 158 /*
 159  * @brief
 160  * result = min(arg1, arg2) := (arg1 <= arg2) ? arg1 : arg2
 161  */
 162 static inline struct fixed31_32 dc_fixpt_min(struct fixed31_32 arg1, struct fixed31_32 arg2)
 163 {
 164         if (arg1.value <= arg2.value)
 165                 return arg1;
 166         else
 167                 return arg2;
 168 }
 169
 170 /*
 171  * @brief
 172  * result = max(arg1, arg2) := (arg1 <= arg2) ? arg2 : arg1
 173  */
 174 static inline struct fixed31_32 dc_fixpt_max(struct fixed31_32 arg1, struct fixed31_32 arg2)
 175 {
 176         if (arg1.value <= arg2.value)
 177                 return arg2;
 178         else
 179                 return arg1;
 180 }
 181
 182 /*
 183  * @brief
 184  *          | min_value, when arg <= min_value
 185  * result = | arg, when min_value < arg < max_value
 186  *          | max_value, when arg >= max_value
 187  */
 188 static inline struct fixed31_32 dc_fixpt_clamp(
 189         struct fixed31_32 arg,
 190         struct fixed31_32 min_value,
 191         struct fixed31_32 max_value)
 192 {
 193         if (dc_fixpt_le(arg, min_value))
 194                 return min_value;
 195         else if (dc_fixpt_le(max_value, arg))
 196                 return max_value;
 197         else
 198                 return arg;
 199 }
 200
 201 /*
 202  * @brief
 203  * Binary shift operators
 204  */
 205
 206 /*
 207  * @brief
 208  * result = arg << shift
 209  */
 210 static inline struct fixed31_32 dc_fixpt_shl(struct fixed31_32 arg, unsigned char shift)
 211 {
 212         ASSERT(((arg.value >= 0) && (arg.value <= LLONG_MAX >> shift)) ||
 213                 ((arg.value < 0) && (arg.value >= ~(LLONG_MAX >> shift))));
 214
 215         arg.value = arg.value << shift;
 216
 217         return arg;
 218 }
 219
 220 /*
 221  * @brief
 222  * result = arg >> shift
 223  */
 224 static inline struct fixed31_32 dc_fixpt_shr(struct fixed31_32 arg, unsigned char shift)
 225 {
 226         bool negative = arg.value < 0;
 227
 228         if (negative)
 229                 arg.value = -arg.value;
 230         arg.value = arg.value >> shift;
 231         if (negative)
 232                 arg.value = -arg.value;
 233         return arg;
 234 }
 235
 236 /*
 237  * @brief
 238  * Binary additive operators
 239  */
 240
 241 /*
 242  * @brief
 243  * result = arg1 + arg2
 244  */
 245 static inline struct fixed31_32 dc_fixpt_add(struct fixed31_32 arg1, struct fixed31_32 arg2)
 246 {
 247         struct fixed31_32 res;
 248
 249         ASSERT(((arg1.value >= 0) && (LLONG_MAX - arg1.value >= arg2.value)) ||
 250                 ((arg1.value < 0) && (LLONG_MIN - arg1.value <= arg2.value)));
 251
 252         res.value = arg1.value + arg2.value;
 253
 254         return res;
 255 }
 256
 257 /*
 258  * @brief
 259  * result = arg1 + arg2
 260  */
 261 static inline struct fixed31_32 dc_fixpt_add_int(struct fixed31_32 arg1, int arg2)
 262 {
 263         return dc_fixpt_add(arg1, dc_fixpt_from_int(arg2));
 264 }
 265
 266 /*
 267  * @brief
 268  * result = arg1 - arg2
 269  */
 270 static inline struct fixed31_32 dc_fixpt_sub(struct fixed31_32 arg1, struct fixed31_32 arg2)
 271 {
 272         struct fixed31_32 res;
 273
 274         ASSERT(((arg2.value >= 0) && (LLONG_MIN + arg2.value <= arg1.value)) ||
 275                 ((arg2.value < 0) && (LLONG_MAX + arg2.value >= arg1.value)));
 276
 277         res.value = arg1.value - arg2.value;
 278
 279         return res;
 280 }
 281
 282 /*
 283  * @brief
 284  * result = arg1 - arg2
 285  */
 286 static inline struct fixed31_32 dc_fixpt_sub_int(struct fixed31_32 arg1, int arg2)
 287 {
 288         return dc_fixpt_sub(arg1, dc_fixpt_from_int(arg2));
 289 }
 290
 291
 292 /*
 293  * @brief
 294  * Binary multiplicative operators
 295  */
 296
 297 /*
 298  * @brief
 299  * result = arg1 * arg2
 300  */
 301 struct fixed31_32 dc_fixpt_mul(struct fixed31_32 arg1, struct fixed31_32 arg2);
 302
 303
 304 /*
 305  * @brief
 306  * result = arg1 * arg2
 307  */
 308 static inline struct fixed31_32 dc_fixpt_mul_int(struct fixed31_32 arg1, int arg2)
 309 {
 310         return dc_fixpt_mul(arg1, dc_fixpt_from_int(arg2));
 311 }
 312
 313 /*
 314  * @brief
 315  * result = square(arg) := arg * arg
 316  */
 317 struct fixed31_32 dc_fixpt_sqr(struct fixed31_32 arg);
 318
 319 /*
 320  * @brief
 321  * result = arg1 / arg2
 322  */
 323 static inline struct fixed31_32 dc_fixpt_div_int(struct fixed31_32 arg1, long long arg2)
 324 {
 325         return dc_fixpt_from_fraction(arg1.value, dc_fixpt_from_int(arg2).value);
 326 }
 327
 328 /*
 329  * @brief
 330  * result = arg1 / arg2
 331  */
 332 static inline struct fixed31_32 dc_fixpt_div(struct fixed31_32 arg1, struct fixed31_32 arg2)
 333 {
 334         return dc_fixpt_from_fraction(arg1.value, arg2.value);
 335 }
 336
 337 /*
 338  * @brief
 339  * Reciprocal function
 340  */
 341
 342 /*
 343  * @brief
 344  * result = reciprocal(arg) := 1 / arg
 345  *
 346  * @note
 347  * No special actions taken in case argument is zero.
 348  */
 349 struct fixed31_32 dc_fixpt_recip(struct fixed31_32 arg);
 350
 351 /*
 352  * @brief
 353  * Trigonometric functions
 354  */
 355
 356 /*
 357  * @brief
 358  * result = sinc(arg) := sin(arg) / arg
 359  *
 360  * @note
 361  * Argument specified in radians,
 362  * internally it's normalized to [-2pi...2pi] range.
 363  */
 364 struct fixed31_32 dc_fixpt_sinc(struct fixed31_32 arg);
 365
 366 /*
 367  * @brief
 368  * result = sin(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_sin(struct fixed31_32 arg);
 375
 376 /*
 377  * @brief
 378  * result = cos(arg)
 379  *
 380  * @note
 381  * Argument specified in radians
 382  * and should be in [-2pi...2pi] range -
 383  * passing arguments outside that range
 384  * will cause incorrect result!
 385  */
 386 struct fixed31_32 dc_fixpt_cos(struct fixed31_32 arg);
 387
 388 /*
 389  * @brief
 390  * Transcendent functions
 391  */
 392
 393 /*
 394  * @brief
 395  * result = exp(arg)
 396  *
 397  * @note
 398  * Currently, function is verified for abs(arg) <= 1.
 399  */
 400 struct fixed31_32 dc_fixpt_exp(struct fixed31_32 arg);
 401
 402 /*
 403  * @brief
 404  * result = log(arg)
 405  *
 406  * @note
 407  * Currently, abs(arg) should be less than 1.
 408  * No normalization is done.
 409  * Currently, no special actions taken
 410  * in case of invalid argument(s). Take care!
 411  */
 412 struct fixed31_32 dc_fixpt_log(struct fixed31_32 arg);
 413
 414 /*
 415  * @brief
 416  * Power function
 417  */
 418
 419 /*
 420  * @brief
 421  * result = pow(arg1, arg2)
 422  *
 423  * @note
 424  * Currently, abs(arg1) should be less than 1. Take care!
 425  */
 426 static inline struct fixed31_32 dc_fixpt_pow(struct fixed31_32 arg1, struct fixed31_32 arg2)
 427 {
 428         if (arg1.value == 0)
 429                 return arg2.value == 0 ? dc_fixpt_one : dc_fixpt_zero;
 430
 431         return dc_fixpt_exp(
 432                 dc_fixpt_mul(
 433                         dc_fixpt_log(arg1),
 434                         arg2));
 435 }
 436
 437 /*
 438  * @brief
 439  * Rounding functions
 440  */
 441
 442 /*
 443  * @brief
 444  * result = floor(arg) := greatest integer lower than or equal to arg
 445  */
 446 static inline int dc_fixpt_floor(struct fixed31_32 arg)
 447 {
 448         unsigned long long arg_value = arg.value > 0 ? arg.value : -arg.value;
 449
 450         if (arg.value >= 0)
 451                 return (int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART);
 452         else
 453                 return -(int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART);
 454 }
 455
 456 /*
 457  * @brief
 458  * result = round(arg) := integer nearest to arg
 459  */
 460 static inline int dc_fixpt_round(struct fixed31_32 arg)
 461 {
 462         unsigned long long arg_value = arg.value > 0 ? arg.value : -arg.value;
 463
 464         const long long summand = dc_fixpt_half.value;
 465
 466         ASSERT(LLONG_MAX - (long long)arg_value >= summand);
 467
 468         arg_value += summand;
 469
 470         if (arg.value >= 0)
 471                 return (int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART);
 472         else
 473                 return -(int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART);
 474 }
 475
 476 /*
 477  * @brief
 478  * result = ceil(arg) := lowest integer greater than or equal to arg
 479  */
 480 static inline int dc_fixpt_ceil(struct fixed31_32 arg)
 481 {
 482         unsigned long long arg_value = arg.value > 0 ? arg.value : -arg.value;
 483
 484         const long long summand = dc_fixpt_one.value -
 485                 dc_fixpt_epsilon.value;
 486
 487         ASSERT(LLONG_MAX - (long long)arg_value >= summand);
 488
 489         arg_value += summand;
 490
 491         if (arg.value >= 0)
 492                 return (int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART);
 493         else
 494                 return -(int)(arg_value >> FIXED31_32_BITS_PER_FRACTIONAL_PART);
 495 }
 496
 497 /* the following two function are used in scaler hw programming to convert fixed
 498  * point value to format 2 bits from integer part and 19 bits from fractional
 499  * part. The same applies for u0d19, 0 bits from integer part and 19 bits from
 500  * fractional
 501  */
 502
 503 unsigned int dc_fixpt_u4d19(struct fixed31_32 arg);
 504
 505 unsigned int dc_fixpt_u3d19(struct fixed31_32 arg);
 506
 507 unsigned int dc_fixpt_u2d19(struct fixed31_32 arg);
 508
 509 unsigned int dc_fixpt_u0d19(struct fixed31_32 arg);
 510
 511 unsigned int dc_fixpt_clamp_u0d14(struct fixed31_32 arg);
 512
 513 unsigned int dc_fixpt_clamp_u0d10(struct fixed31_32 arg);
 514
 515 int dc_fixpt_s4d19(struct fixed31_32 arg);
 516
 517 static inline struct fixed31_32 dc_fixpt_truncate(struct fixed31_32 arg, unsigned int frac_bits)
 518 {
 519         bool negative = arg.value < 0;
 520
 521         if (frac_bits >= FIXED31_32_BITS_PER_FRACTIONAL_PART) {
 522                 ASSERT(frac_bits == FIXED31_32_BITS_PER_FRACTIONAL_PART);
 523                 return arg;
 524         }
 525
 526         if (negative)
 527                 arg.value = -arg.value;
 528         arg.value &= (~0LL) << (FIXED31_32_BITS_PER_FRACTIONAL_PART - frac_bits);
 529         if (negative)
 530                 arg.value = -arg.value;
 531         return arg;
 532 }
 533
 534 #endif