1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Support for Intel Camera Imaging ISP subsystem. 4 * Copyright (c) 2015, Intel Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms and conditions of the GNU General Public License, 8 * version 2, as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 */ 15 16 #include <linux/slab.h> 17 18 #include <math_support.h> 19 #include "sh_css_param_shading.h" 20 #include "ia_css_shading.h" 21 #include "assert_support.h" 22 #include "sh_css_defs.h" 23 #include "sh_css_internal.h" 24 #include "ia_css_debug.h" 25 #include "ia_css_pipe_binarydesc.h" 26 27 #include "sh_css_hrt.h" 28 29 #include "platform_support.h" 30 31 /* Bilinear interpolation on shading tables: 32 * For each target point T, we calculate the 4 surrounding source points: 33 * ul (upper left), ur (upper right), ll (lower left) and lr (lower right). 34 * We then calculate the distances from the T to the source points: x0, x1, 35 * y0 and y1. 36 * We then calculate the value of T: 37 * dx0*dy0*Slr + dx0*dy1*Sur + dx1*dy0*Sll + dx1*dy1*Sul. 38 * We choose a grid size of 1x1 which means: 39 * dx1 = 1-dx0 40 * dy1 = 1-dy0 41 * 42 * Sul dx0 dx1 Sur 43 * .<----->|<------------->. 44 * ^ 45 * dy0| 46 * v T 47 * - . 48 * ^ 49 * | 50 * dy1| 51 * v 52 * . . 53 * Sll Slr 54 * 55 * Padding: 56 * The area that the ISP operates on can include padding both on the left 57 * and the right. We need to padd the shading table such that the shading 58 * values end up on the correct pixel values. This means we must padd the 59 * shading table to match the ISP padding. 60 * We can have 5 cases: 61 * 1. All 4 points fall in the left padding. 62 * 2. The left 2 points fall in the left padding. 63 * 3. All 4 points fall in the cropped (target) region. 64 * 4. The right 2 points fall in the right padding. 65 * 5. All 4 points fall in the right padding. 66 * Cases 1 and 5 are easy to handle: we simply use the 67 * value 1 in the shading table. 68 * Cases 2 and 4 require interpolation that takes into 69 * account how far into the padding area the pixels 70 * fall. We extrapolate the shading table into the 71 * padded area and then interpolate. 72 */ 73 static void 74 crop_and_interpolate(unsigned int cropped_width, 75 unsigned int cropped_height, 76 unsigned int left_padding, 77 int right_padding, 78 int top_padding, 79 const struct ia_css_shading_table *in_table, 80 struct ia_css_shading_table *out_table, 81 enum ia_css_sc_color color) 82 { 83 unsigned int i, j, 84 sensor_width, 85 sensor_height, 86 table_width, 87 table_height, 88 table_cell_h, 89 out_cell_size, 90 in_cell_size, 91 out_start_row, 92 padded_width; 93 int out_start_col, /* can be negative to indicate padded space */ 94 table_cell_w; 95 unsigned short *in_ptr, 96 *out_ptr; 97 98 assert(in_table); 99 assert(out_table); 100 101 sensor_width = in_table->sensor_width; 102 sensor_height = in_table->sensor_height; 103 table_width = in_table->width; 104 table_height = in_table->height; 105 in_ptr = in_table->data[color]; 106 out_ptr = out_table->data[color]; 107 108 padded_width = cropped_width + left_padding + right_padding; 109 out_cell_size = CEIL_DIV(padded_width, out_table->width - 1); 110 in_cell_size = CEIL_DIV(sensor_width, table_width - 1); 111 112 out_start_col = ((int)sensor_width - (int)cropped_width) / 2 - left_padding; 113 out_start_row = ((int)sensor_height - (int)cropped_height) / 2 - top_padding; 114 table_cell_w = (int)((table_width - 1) * in_cell_size); 115 table_cell_h = (table_height - 1) * in_cell_size; 116 117 for (i = 0; i < out_table->height; i++) { 118 int ty, src_y0, src_y1; 119 unsigned int sy0, sy1, dy0, dy1, divy; 120 121 /* 122 * calculate target point and make sure it falls within 123 * the table 124 */ 125 ty = out_start_row + i * out_cell_size; 126 127 /* calculate closest source points in shading table and 128 make sure they fall within the table */ 129 src_y0 = ty / (int)in_cell_size; 130 if (in_cell_size < out_cell_size) 131 src_y1 = (ty + out_cell_size) / in_cell_size; 132 else 133 src_y1 = src_y0 + 1; 134 src_y0 = clamp(src_y0, 0, (int)table_height - 1); 135 src_y1 = clamp(src_y1, 0, (int)table_height - 1); 136 ty = min(clamp(ty, 0, (int)sensor_height - 1), 137 (int)table_cell_h); 138 139 /* calculate closest source points for distance computation */ 140 sy0 = min(src_y0 * in_cell_size, sensor_height - 1); 141 sy1 = min(src_y1 * in_cell_size, sensor_height - 1); 142 /* calculate distance between source and target pixels */ 143 dy0 = ty - sy0; 144 dy1 = sy1 - ty; 145 divy = sy1 - sy0; 146 if (divy == 0) { 147 dy0 = 1; 148 divy = 1; 149 } 150 151 for (j = 0; j < out_table->width; j++, out_ptr++) { 152 int tx, src_x0, src_x1; 153 unsigned int sx0, sx1, dx0, dx1, divx; 154 unsigned short s_ul, s_ur, s_ll, s_lr; 155 156 /* calculate target point */ 157 tx = out_start_col + j * out_cell_size; 158 /* calculate closest source points. */ 159 src_x0 = tx / (int)in_cell_size; 160 if (in_cell_size < out_cell_size) { 161 src_x1 = (tx + out_cell_size) / 162 (int)in_cell_size; 163 } else { 164 src_x1 = src_x0 + 1; 165 } 166 /* if src points fall in padding, select closest ones.*/ 167 src_x0 = clamp(src_x0, 0, (int)table_width - 1); 168 src_x1 = clamp(src_x1, 0, (int)table_width - 1); 169 tx = min(clamp(tx, 0, (int)sensor_width - 1), 170 (int)table_cell_w); 171 /* 172 * calculate closest source points for distance 173 * computation 174 */ 175 sx0 = min(src_x0 * in_cell_size, sensor_width - 1); 176 sx1 = min(src_x1 * in_cell_size, sensor_width - 1); 177 /* 178 * calculate distances between source and target 179 * pixels 180 */ 181 dx0 = tx - sx0; 182 dx1 = sx1 - tx; 183 divx = sx1 - sx0; 184 /* if we're at the edge, we just use the closest 185 * point still in the grid. We make up for the divider 186 * in this case by setting the distance to 187 * out_cell_size, since it's actually 0. 188 */ 189 if (divx == 0) { 190 dx0 = 1; 191 divx = 1; 192 } 193 194 /* get source pixel values */ 195 s_ul = in_ptr[(table_width * src_y0) + src_x0]; 196 s_ur = in_ptr[(table_width * src_y0) + src_x1]; 197 s_ll = in_ptr[(table_width * src_y1) + src_x0]; 198 s_lr = in_ptr[(table_width * src_y1) + src_x1]; 199 200 *out_ptr = (unsigned short)((dx0 * dy0 * s_lr + dx0 * dy1 * s_ur + dx1 * dy0 * 201 s_ll + dx1 * dy1 * s_ul) / 202 (divx * divy)); 203 } 204 } 205 } 206 207 void 208 sh_css_params_shading_id_table_generate( 209 struct ia_css_shading_table **target_table, 210 unsigned int table_width, 211 unsigned int table_height) 212 { 213 /* initialize table with ones, shift becomes zero */ 214 unsigned int i, j; 215 struct ia_css_shading_table *result; 216 217 assert(target_table); 218 219 result = ia_css_shading_table_alloc(table_width, table_height); 220 if (!result) { 221 *target_table = NULL; 222 return; 223 } 224 225 for (i = 0; i < IA_CSS_SC_NUM_COLORS; i++) { 226 for (j = 0; j < table_height * table_width; j++) 227 result->data[i][j] = 1; 228 } 229 result->fraction_bits = 0; 230 *target_table = result; 231 } 232 233 void 234 prepare_shading_table(const struct ia_css_shading_table *in_table, 235 unsigned int sensor_binning, 236 struct ia_css_shading_table **target_table, 237 const struct ia_css_binary *binary, 238 unsigned int bds_factor) 239 { 240 unsigned int input_width, input_height, table_width, table_height, i; 241 unsigned int left_padding, top_padding, left_cropping; 242 unsigned int bds_numerator, bds_denominator; 243 int right_padding; 244 245 struct ia_css_shading_table *result; 246 247 assert(target_table); 248 assert(binary); 249 250 if (!in_table) { 251 sh_css_params_shading_id_table_generate(target_table, 252 binary->sctbl_width_per_color, 253 binary->sctbl_height); 254 return; 255 } 256 257 /* 258 * We use the ISP input resolution for the shading table because 259 * shading correction is performed in the bayer domain (before bayer 260 * down scaling). 261 */ 262 input_height = binary->in_frame_info.res.height; 263 input_width = binary->in_frame_info.res.width; 264 left_padding = binary->left_padding; 265 left_cropping = (binary->info->sp.pipeline.left_cropping == 0) ? 266 binary->dvs_envelope.width : 2 * ISP_VEC_NELEMS; 267 268 sh_css_bds_factor_get_numerator_denominator 269 (bds_factor, &bds_numerator, &bds_denominator); 270 271 left_padding = (left_padding + binary->info->sp.pipeline.left_cropping) * 272 bds_numerator / bds_denominator - 273 binary->info->sp.pipeline.left_cropping; 274 right_padding = (binary->internal_frame_info.res.width - 275 binary->effective_in_frame_res.width * bds_denominator / 276 bds_numerator - left_cropping) * bds_numerator / bds_denominator; 277 top_padding = binary->info->sp.pipeline.top_cropping * bds_numerator / 278 bds_denominator - 279 binary->info->sp.pipeline.top_cropping; 280 281 /* 282 * We take into account the binning done by the sensor. We do this 283 * by cropping the non-binned part of the shading table and then 284 * increasing the size of a grid cell with this same binning factor. 285 */ 286 input_width <<= sensor_binning; 287 input_height <<= sensor_binning; 288 /* 289 * We also scale the padding by the same binning factor. This will 290 * make it much easier later on to calculate the padding of the 291 * shading table. 292 */ 293 left_padding <<= sensor_binning; 294 right_padding <<= sensor_binning; 295 top_padding <<= sensor_binning; 296 297 /* 298 * during simulation, the used resolution can exceed the sensor 299 * resolution, so we clip it. 300 */ 301 input_width = min(input_width, in_table->sensor_width); 302 input_height = min(input_height, in_table->sensor_height); 303 304 /* This prepare_shading_table() function is called only in legacy API (not in new API). 305 Then, the legacy shading table width and height should be used. */ 306 table_width = binary->sctbl_width_per_color; 307 table_height = binary->sctbl_height; 308 309 result = ia_css_shading_table_alloc(table_width, table_height); 310 if (!result) { 311 *target_table = NULL; 312 return; 313 } 314 result->sensor_width = in_table->sensor_width; 315 result->sensor_height = in_table->sensor_height; 316 result->fraction_bits = in_table->fraction_bits; 317 318 /* 319 * now we crop the original shading table and then interpolate to the 320 * requested resolution and decimation factor. 321 */ 322 for (i = 0; i < IA_CSS_SC_NUM_COLORS; i++) { 323 crop_and_interpolate(input_width, input_height, 324 left_padding, right_padding, top_padding, 325 in_table, 326 result, i); 327 } 328 *target_table = result; 329 } 330 331 struct ia_css_shading_table * 332 ia_css_shading_table_alloc( 333 unsigned int width, 334 unsigned int height) 335 { 336 unsigned int i; 337 struct ia_css_shading_table *me; 338 339 IA_CSS_ENTER(""); 340 341 me = kmalloc(sizeof(*me), GFP_KERNEL); 342 if (!me) 343 return me; 344 345 me->width = width; 346 me->height = height; 347 me->sensor_width = 0; 348 me->sensor_height = 0; 349 me->fraction_bits = 0; 350 for (i = 0; i < IA_CSS_SC_NUM_COLORS; i++) { 351 me->data[i] = 352 kvmalloc(width * height * sizeof(*me->data[0]), 353 GFP_KERNEL); 354 if (!me->data[i]) { 355 unsigned int j; 356 357 for (j = 0; j < i; j++) { 358 kvfree(me->data[j]); 359 me->data[j] = NULL; 360 } 361 kfree(me); 362 return NULL; 363 } 364 } 365 366 IA_CSS_LEAVE(""); 367 return me; 368 } 369 370 void 371 ia_css_shading_table_free(struct ia_css_shading_table *table) 372 { 373 unsigned int i; 374 375 if (!table) 376 return; 377 378 /* 379 * We only output logging when the table is not NULL, otherwise 380 * logs will give the impression that a table was freed. 381 */ 382 IA_CSS_ENTER(""); 383 384 for (i = 0; i < IA_CSS_SC_NUM_COLORS; i++) { 385 if (table->data[i]) { 386 kvfree(table->data[i]); 387 table->data[i] = NULL; 388 } 389 } 390 kfree(table); 391 392 IA_CSS_LEAVE(""); 393 } 394