1 /* 2 * Copyright (c) 2016 Intel Corporation 3 * 4 * Permission to use, copy, modify, distribute, and sell this software and its 5 * documentation for any purpose is hereby granted without fee, provided that 6 * the above copyright notice appear in all copies and that both that copyright 7 * notice and this permission notice appear in supporting documentation, and 8 * that the name of the copyright holders not be used in advertising or 9 * publicity pertaining to distribution of the software without specific, 10 * written prior permission. The copyright holders make no representations 11 * about the suitability of this software for any purpose. It is provided "as 12 * is" without express or implied warranty. 13 * 14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO 16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR 17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, 18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 20 * OF THIS SOFTWARE. 21 */ 22 23 #include <linux/uaccess.h> 24 25 #include <drm/drm_atomic.h> 26 #include <drm/drm_color_mgmt.h> 27 #include <drm/drm_crtc.h> 28 #include <drm/drm_device.h> 29 #include <drm/drm_drv.h> 30 #include <drm/drm_print.h> 31 32 #include "drm_crtc_internal.h" 33 34 /** 35 * DOC: overview 36 * 37 * Color management or color space adjustments is supported through a set of 5 38 * properties on the &drm_crtc object. They are set up by calling 39 * drm_crtc_enable_color_mgmt(). 40 * 41 * "DEGAMMA_LUT”: 42 * Blob property to set the degamma lookup table (LUT) mapping pixel data 43 * from the framebuffer before it is given to the transformation matrix. 44 * The data is interpreted as an array of &struct drm_color_lut elements. 45 * Hardware might choose not to use the full precision of the LUT elements 46 * nor use all the elements of the LUT (for example the hardware might 47 * choose to interpolate between LUT[0] and LUT[4]). 48 * 49 * Setting this to NULL (blob property value set to 0) means a 50 * linear/pass-thru gamma table should be used. This is generally the 51 * driver boot-up state too. Drivers can access this blob through 52 * &drm_crtc_state.degamma_lut. 53 * 54 * “DEGAMMA_LUT_SIZE”: 55 * Unsinged range property to give the size of the lookup table to be set 56 * on the DEGAMMA_LUT property (the size depends on the underlying 57 * hardware). If drivers support multiple LUT sizes then they should 58 * publish the largest size, and sub-sample smaller sized LUTs (e.g. for 59 * split-gamma modes) appropriately. 60 * 61 * “CTM”: 62 * Blob property to set the current transformation matrix (CTM) apply to 63 * pixel data after the lookup through the degamma LUT and before the 64 * lookup through the gamma LUT. The data is interpreted as a struct 65 * &drm_color_ctm. 66 * 67 * Setting this to NULL (blob property value set to 0) means a 68 * unit/pass-thru matrix should be used. This is generally the driver 69 * boot-up state too. Drivers can access the blob for the color conversion 70 * matrix through &drm_crtc_state.ctm. 71 * 72 * “GAMMA_LUT”: 73 * Blob property to set the gamma lookup table (LUT) mapping pixel data 74 * after the transformation matrix to data sent to the connector. The 75 * data is interpreted as an array of &struct drm_color_lut elements. 76 * Hardware might choose not to use the full precision of the LUT elements 77 * nor use all the elements of the LUT (for example the hardware might 78 * choose to interpolate between LUT[0] and LUT[4]). 79 * 80 * Setting this to NULL (blob property value set to 0) means a 81 * linear/pass-thru gamma table should be used. This is generally the 82 * driver boot-up state too. Drivers can access this blob through 83 * &drm_crtc_state.gamma_lut. 84 * 85 * “GAMMA_LUT_SIZE”: 86 * Unsigned range property to give the size of the lookup table to be set 87 * on the GAMMA_LUT property (the size depends on the underlying hardware). 88 * If drivers support multiple LUT sizes then they should publish the 89 * largest size, and sub-sample smaller sized LUTs (e.g. for split-gamma 90 * modes) appropriately. 91 * 92 * There is also support for a legacy gamma table, which is set up by calling 93 * drm_mode_crtc_set_gamma_size(). The DRM core will then alias the legacy gamma 94 * ramp with "GAMMA_LUT" or, if that is unavailable, "DEGAMMA_LUT". 95 * 96 * Support for different non RGB color encodings is controlled through 97 * &drm_plane specific COLOR_ENCODING and COLOR_RANGE properties. They 98 * are set up by calling drm_plane_create_color_properties(). 99 * 100 * "COLOR_ENCODING": 101 * Optional plane enum property to support different non RGB 102 * color encodings. The driver can provide a subset of standard 103 * enum values supported by the DRM plane. 104 * 105 * "COLOR_RANGE": 106 * Optional plane enum property to support different non RGB 107 * color parameter ranges. The driver can provide a subset of 108 * standard enum values supported by the DRM plane. 109 */ 110 111 /** 112 * drm_color_ctm_s31_32_to_qm_n 113 * 114 * @user_input: input value 115 * @m: number of integer bits, only support m <= 32, include the sign-bit 116 * @n: number of fractional bits, only support n <= 32 117 * 118 * Convert and clamp S31.32 sign-magnitude to Qm.n (signed 2's complement). 119 * The sign-bit BIT(m+n-1) and above are 0 for positive value and 1 for negative 120 * the range of value is [-2^(m-1), 2^(m-1) - 2^-n] 121 * 122 * For example 123 * A Q3.12 format number: 124 * - required bit: 3 + 12 = 15bits 125 * - range: [-2^2, 2^2 - 2^−15] 126 * 127 * NOTE: the m can be zero if all bit_precision are used to present fractional 128 * bits like Q0.32 129 */ 130 u64 drm_color_ctm_s31_32_to_qm_n(u64 user_input, u32 m, u32 n) 131 { 132 u64 mag = (user_input & ~BIT_ULL(63)) >> (32 - n); 133 bool negative = !!(user_input & BIT_ULL(63)); 134 s64 val; 135 136 WARN_ON(m > 32 || n > 32); 137 138 val = clamp_val(mag, 0, negative ? 139 BIT_ULL(n + m - 1) : BIT_ULL(n + m - 1) - 1); 140 141 return negative ? -val : val; 142 } 143 EXPORT_SYMBOL(drm_color_ctm_s31_32_to_qm_n); 144 145 /** 146 * drm_crtc_enable_color_mgmt - enable color management properties 147 * @crtc: DRM CRTC 148 * @degamma_lut_size: the size of the degamma lut (before CSC) 149 * @has_ctm: whether to attach ctm_property for CSC matrix 150 * @gamma_lut_size: the size of the gamma lut (after CSC) 151 * 152 * This function lets the driver enable the color correction 153 * properties on a CRTC. This includes 3 degamma, csc and gamma 154 * properties that userspace can set and 2 size properties to inform 155 * the userspace of the lut sizes. Each of the properties are 156 * optional. The gamma and degamma properties are only attached if 157 * their size is not 0 and ctm_property is only attached if has_ctm is 158 * true. 159 */ 160 void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc, 161 uint degamma_lut_size, 162 bool has_ctm, 163 uint gamma_lut_size) 164 { 165 struct drm_device *dev = crtc->dev; 166 struct drm_mode_config *config = &dev->mode_config; 167 168 if (degamma_lut_size) { 169 drm_object_attach_property(&crtc->base, 170 config->degamma_lut_property, 0); 171 drm_object_attach_property(&crtc->base, 172 config->degamma_lut_size_property, 173 degamma_lut_size); 174 } 175 176 if (has_ctm) 177 drm_object_attach_property(&crtc->base, 178 config->ctm_property, 0); 179 180 if (gamma_lut_size) { 181 drm_object_attach_property(&crtc->base, 182 config->gamma_lut_property, 0); 183 drm_object_attach_property(&crtc->base, 184 config->gamma_lut_size_property, 185 gamma_lut_size); 186 } 187 } 188 EXPORT_SYMBOL(drm_crtc_enable_color_mgmt); 189 190 /** 191 * drm_mode_crtc_set_gamma_size - set the gamma table size 192 * @crtc: CRTC to set the gamma table size for 193 * @gamma_size: size of the gamma table 194 * 195 * Drivers which support gamma tables should set this to the supported gamma 196 * table size when initializing the CRTC. Currently the drm core only supports a 197 * fixed gamma table size. 198 * 199 * Returns: 200 * Zero on success, negative errno on failure. 201 */ 202 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc, 203 int gamma_size) 204 { 205 uint16_t *r_base, *g_base, *b_base; 206 int i; 207 208 crtc->gamma_size = gamma_size; 209 210 crtc->gamma_store = kcalloc(gamma_size, sizeof(uint16_t) * 3, 211 GFP_KERNEL); 212 if (!crtc->gamma_store) { 213 crtc->gamma_size = 0; 214 return -ENOMEM; 215 } 216 217 r_base = crtc->gamma_store; 218 g_base = r_base + gamma_size; 219 b_base = g_base + gamma_size; 220 for (i = 0; i < gamma_size; i++) { 221 r_base[i] = i << 8; 222 g_base[i] = i << 8; 223 b_base[i] = i << 8; 224 } 225 226 227 return 0; 228 } 229 EXPORT_SYMBOL(drm_mode_crtc_set_gamma_size); 230 231 /** 232 * drm_crtc_supports_legacy_gamma - does the crtc support legacy gamma correction table 233 * @crtc: CRTC object 234 * 235 * Returns true/false if the given crtc supports setting the legacy gamma 236 * correction table. 237 */ 238 static bool drm_crtc_supports_legacy_gamma(struct drm_crtc *crtc) 239 { 240 u32 gamma_id = crtc->dev->mode_config.gamma_lut_property->base.id; 241 u32 degamma_id = crtc->dev->mode_config.degamma_lut_property->base.id; 242 243 if (!crtc->gamma_size) 244 return false; 245 246 if (crtc->funcs->gamma_set) 247 return true; 248 249 return !!(drm_mode_obj_find_prop_id(&crtc->base, gamma_id) || 250 drm_mode_obj_find_prop_id(&crtc->base, degamma_id)); 251 } 252 253 /** 254 * drm_crtc_legacy_gamma_set - set the legacy gamma correction table 255 * @crtc: CRTC object 256 * @red: red correction table 257 * @green: green correction table 258 * @blue: green correction table 259 * @size: size of the tables 260 * @ctx: lock acquire context 261 * 262 * Implements support for legacy gamma correction table for drivers 263 * that have set drm_crtc_funcs.gamma_set or that support color management 264 * through the DEGAMMA_LUT/GAMMA_LUT properties. See 265 * drm_crtc_enable_color_mgmt() and the containing chapter for 266 * how the atomic color management and gamma tables work. 267 * 268 * This function sets the gamma using drm_crtc_funcs.gamma_set if set, or 269 * alternatively using crtc color management properties. 270 */ 271 static int drm_crtc_legacy_gamma_set(struct drm_crtc *crtc, 272 u16 *red, u16 *green, u16 *blue, 273 u32 size, 274 struct drm_modeset_acquire_ctx *ctx) 275 { 276 struct drm_device *dev = crtc->dev; 277 struct drm_atomic_state *state; 278 struct drm_crtc_state *crtc_state; 279 struct drm_property_blob *blob; 280 struct drm_color_lut *blob_data; 281 u32 gamma_id = dev->mode_config.gamma_lut_property->base.id; 282 u32 degamma_id = dev->mode_config.degamma_lut_property->base.id; 283 bool use_gamma_lut; 284 int i, ret = 0; 285 bool replaced; 286 287 if (crtc->funcs->gamma_set) 288 return crtc->funcs->gamma_set(crtc, red, green, blue, size, ctx); 289 290 if (drm_mode_obj_find_prop_id(&crtc->base, gamma_id)) 291 use_gamma_lut = true; 292 else if (drm_mode_obj_find_prop_id(&crtc->base, degamma_id)) 293 use_gamma_lut = false; 294 else 295 return -ENODEV; 296 297 state = drm_atomic_state_alloc(crtc->dev); 298 if (!state) 299 return -ENOMEM; 300 301 blob = drm_property_create_blob(dev, 302 sizeof(struct drm_color_lut) * size, 303 NULL); 304 if (IS_ERR(blob)) { 305 ret = PTR_ERR(blob); 306 blob = NULL; 307 goto fail; 308 } 309 310 /* Prepare GAMMA_LUT with the legacy values. */ 311 blob_data = blob->data; 312 for (i = 0; i < size; i++) { 313 blob_data[i].red = red[i]; 314 blob_data[i].green = green[i]; 315 blob_data[i].blue = blue[i]; 316 } 317 318 state->acquire_ctx = ctx; 319 crtc_state = drm_atomic_get_crtc_state(state, crtc); 320 if (IS_ERR(crtc_state)) { 321 ret = PTR_ERR(crtc_state); 322 goto fail; 323 } 324 325 /* Set GAMMA_LUT and reset DEGAMMA_LUT and CTM */ 326 replaced = drm_property_replace_blob(&crtc_state->degamma_lut, 327 use_gamma_lut ? NULL : blob); 328 replaced |= drm_property_replace_blob(&crtc_state->ctm, NULL); 329 replaced |= drm_property_replace_blob(&crtc_state->gamma_lut, 330 use_gamma_lut ? blob : NULL); 331 crtc_state->color_mgmt_changed |= replaced; 332 333 ret = drm_atomic_commit(state); 334 335 fail: 336 drm_atomic_state_put(state); 337 drm_property_blob_put(blob); 338 return ret; 339 } 340 341 /** 342 * drm_mode_gamma_set_ioctl - set the gamma table 343 * @dev: DRM device 344 * @data: ioctl data 345 * @file_priv: DRM file info 346 * 347 * Set the gamma table of a CRTC to the one passed in by the user. Userspace can 348 * inquire the required gamma table size through drm_mode_gamma_get_ioctl. 349 * 350 * Called by the user via ioctl. 351 * 352 * Returns: 353 * Zero on success, negative errno on failure. 354 */ 355 int drm_mode_gamma_set_ioctl(struct drm_device *dev, 356 void *data, struct drm_file *file_priv) 357 { 358 struct drm_mode_crtc_lut *crtc_lut = data; 359 struct drm_crtc *crtc; 360 void *r_base, *g_base, *b_base; 361 int size; 362 struct drm_modeset_acquire_ctx ctx; 363 int ret = 0; 364 365 if (!drm_core_check_feature(dev, DRIVER_MODESET)) 366 return -EOPNOTSUPP; 367 368 crtc = drm_crtc_find(dev, file_priv, crtc_lut->crtc_id); 369 if (!crtc) 370 return -ENOENT; 371 372 if (!drm_crtc_supports_legacy_gamma(crtc)) 373 return -ENOSYS; 374 375 /* memcpy into gamma store */ 376 if (crtc_lut->gamma_size != crtc->gamma_size) 377 return -EINVAL; 378 379 DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, ret); 380 381 size = crtc_lut->gamma_size * (sizeof(uint16_t)); 382 r_base = crtc->gamma_store; 383 if (copy_from_user(r_base, (void __user *)(unsigned long)crtc_lut->red, size)) { 384 ret = -EFAULT; 385 goto out; 386 } 387 388 g_base = r_base + size; 389 if (copy_from_user(g_base, (void __user *)(unsigned long)crtc_lut->green, size)) { 390 ret = -EFAULT; 391 goto out; 392 } 393 394 b_base = g_base + size; 395 if (copy_from_user(b_base, (void __user *)(unsigned long)crtc_lut->blue, size)) { 396 ret = -EFAULT; 397 goto out; 398 } 399 400 ret = drm_crtc_legacy_gamma_set(crtc, r_base, g_base, b_base, 401 crtc->gamma_size, &ctx); 402 403 out: 404 DRM_MODESET_LOCK_ALL_END(dev, ctx, ret); 405 return ret; 406 407 } 408 409 /** 410 * drm_mode_gamma_get_ioctl - get the gamma table 411 * @dev: DRM device 412 * @data: ioctl data 413 * @file_priv: DRM file info 414 * 415 * Copy the current gamma table into the storage provided. This also provides 416 * the gamma table size the driver expects, which can be used to size the 417 * allocated storage. 418 * 419 * Called by the user via ioctl. 420 * 421 * Returns: 422 * Zero on success, negative errno on failure. 423 */ 424 int drm_mode_gamma_get_ioctl(struct drm_device *dev, 425 void *data, struct drm_file *file_priv) 426 { 427 struct drm_mode_crtc_lut *crtc_lut = data; 428 struct drm_crtc *crtc; 429 void *r_base, *g_base, *b_base; 430 int size; 431 int ret = 0; 432 433 if (!drm_core_check_feature(dev, DRIVER_MODESET)) 434 return -EOPNOTSUPP; 435 436 crtc = drm_crtc_find(dev, file_priv, crtc_lut->crtc_id); 437 if (!crtc) 438 return -ENOENT; 439 440 /* memcpy into gamma store */ 441 if (crtc_lut->gamma_size != crtc->gamma_size) 442 return -EINVAL; 443 444 drm_modeset_lock(&crtc->mutex, NULL); 445 size = crtc_lut->gamma_size * (sizeof(uint16_t)); 446 r_base = crtc->gamma_store; 447 if (copy_to_user((void __user *)(unsigned long)crtc_lut->red, r_base, size)) { 448 ret = -EFAULT; 449 goto out; 450 } 451 452 g_base = r_base + size; 453 if (copy_to_user((void __user *)(unsigned long)crtc_lut->green, g_base, size)) { 454 ret = -EFAULT; 455 goto out; 456 } 457 458 b_base = g_base + size; 459 if (copy_to_user((void __user *)(unsigned long)crtc_lut->blue, b_base, size)) { 460 ret = -EFAULT; 461 goto out; 462 } 463 out: 464 drm_modeset_unlock(&crtc->mutex); 465 return ret; 466 } 467 468 static const char * const color_encoding_name[] = { 469 [DRM_COLOR_YCBCR_BT601] = "ITU-R BT.601 YCbCr", 470 [DRM_COLOR_YCBCR_BT709] = "ITU-R BT.709 YCbCr", 471 [DRM_COLOR_YCBCR_BT2020] = "ITU-R BT.2020 YCbCr", 472 }; 473 474 static const char * const color_range_name[] = { 475 [DRM_COLOR_YCBCR_FULL_RANGE] = "YCbCr full range", 476 [DRM_COLOR_YCBCR_LIMITED_RANGE] = "YCbCr limited range", 477 }; 478 479 /** 480 * drm_get_color_encoding_name - return a string for color encoding 481 * @encoding: color encoding to compute name of 482 * 483 * In contrast to the other drm_get_*_name functions this one here returns a 484 * const pointer and hence is threadsafe. 485 */ 486 const char *drm_get_color_encoding_name(enum drm_color_encoding encoding) 487 { 488 if (WARN_ON(encoding >= ARRAY_SIZE(color_encoding_name))) 489 return "unknown"; 490 491 return color_encoding_name[encoding]; 492 } 493 494 /** 495 * drm_get_color_range_name - return a string for color range 496 * @range: color range to compute name of 497 * 498 * In contrast to the other drm_get_*_name functions this one here returns a 499 * const pointer and hence is threadsafe. 500 */ 501 const char *drm_get_color_range_name(enum drm_color_range range) 502 { 503 if (WARN_ON(range >= ARRAY_SIZE(color_range_name))) 504 return "unknown"; 505 506 return color_range_name[range]; 507 } 508 509 /** 510 * drm_plane_create_color_properties - color encoding related plane properties 511 * @plane: plane object 512 * @supported_encodings: bitfield indicating supported color encodings 513 * @supported_ranges: bitfileld indicating supported color ranges 514 * @default_encoding: default color encoding 515 * @default_range: default color range 516 * 517 * Create and attach plane specific COLOR_ENCODING and COLOR_RANGE 518 * properties to @plane. The supported encodings and ranges should 519 * be provided in supported_encodings and supported_ranges bitmasks. 520 * Each bit set in the bitmask indicates that its number as enum 521 * value is supported. 522 */ 523 int drm_plane_create_color_properties(struct drm_plane *plane, 524 u32 supported_encodings, 525 u32 supported_ranges, 526 enum drm_color_encoding default_encoding, 527 enum drm_color_range default_range) 528 { 529 struct drm_device *dev = plane->dev; 530 struct drm_property *prop; 531 struct drm_prop_enum_list enum_list[max_t(int, DRM_COLOR_ENCODING_MAX, 532 DRM_COLOR_RANGE_MAX)]; 533 int i, len; 534 535 if (WARN_ON(supported_encodings == 0 || 536 (supported_encodings & -BIT(DRM_COLOR_ENCODING_MAX)) != 0 || 537 (supported_encodings & BIT(default_encoding)) == 0)) 538 return -EINVAL; 539 540 if (WARN_ON(supported_ranges == 0 || 541 (supported_ranges & -BIT(DRM_COLOR_RANGE_MAX)) != 0 || 542 (supported_ranges & BIT(default_range)) == 0)) 543 return -EINVAL; 544 545 len = 0; 546 for (i = 0; i < DRM_COLOR_ENCODING_MAX; i++) { 547 if ((supported_encodings & BIT(i)) == 0) 548 continue; 549 550 enum_list[len].type = i; 551 enum_list[len].name = color_encoding_name[i]; 552 len++; 553 } 554 555 prop = drm_property_create_enum(dev, 0, "COLOR_ENCODING", 556 enum_list, len); 557 if (!prop) 558 return -ENOMEM; 559 plane->color_encoding_property = prop; 560 drm_object_attach_property(&plane->base, prop, default_encoding); 561 if (plane->state) 562 plane->state->color_encoding = default_encoding; 563 564 len = 0; 565 for (i = 0; i < DRM_COLOR_RANGE_MAX; i++) { 566 if ((supported_ranges & BIT(i)) == 0) 567 continue; 568 569 enum_list[len].type = i; 570 enum_list[len].name = color_range_name[i]; 571 len++; 572 } 573 574 prop = drm_property_create_enum(dev, 0, "COLOR_RANGE", 575 enum_list, len); 576 if (!prop) 577 return -ENOMEM; 578 plane->color_range_property = prop; 579 drm_object_attach_property(&plane->base, prop, default_range); 580 if (plane->state) 581 plane->state->color_range = default_range; 582 583 return 0; 584 } 585 EXPORT_SYMBOL(drm_plane_create_color_properties); 586 587 /** 588 * drm_color_lut_check - check validity of lookup table 589 * @lut: property blob containing LUT to check 590 * @tests: bitmask of tests to run 591 * 592 * Helper to check whether a userspace-provided lookup table is valid and 593 * satisfies hardware requirements. Drivers pass a bitmask indicating which of 594 * the tests in &drm_color_lut_tests should be performed. 595 * 596 * Returns 0 on success, -EINVAL on failure. 597 */ 598 int drm_color_lut_check(const struct drm_property_blob *lut, u32 tests) 599 { 600 const struct drm_color_lut *entry; 601 int i; 602 603 if (!lut || !tests) 604 return 0; 605 606 entry = lut->data; 607 for (i = 0; i < drm_color_lut_size(lut); i++) { 608 if (tests & DRM_COLOR_LUT_EQUAL_CHANNELS) { 609 if (entry[i].red != entry[i].blue || 610 entry[i].red != entry[i].green) { 611 DRM_DEBUG_KMS("All LUT entries must have equal r/g/b\n"); 612 return -EINVAL; 613 } 614 } 615 616 if (i > 0 && tests & DRM_COLOR_LUT_NON_DECREASING) { 617 if (entry[i].red < entry[i - 1].red || 618 entry[i].green < entry[i - 1].green || 619 entry[i].blue < entry[i - 1].blue) { 620 DRM_DEBUG_KMS("LUT entries must never decrease.\n"); 621 return -EINVAL; 622 } 623 } 624 } 625 626 return 0; 627 } 628 EXPORT_SYMBOL(drm_color_lut_check); 629