Hi David, url: https://github.com/0day-ci/linux/commits/David-Francis/Make-DRM-DSC-helpers-more-generally-usable/20190214-052541 smatch warnings: drivers/gpu/drm/drm_dsc.c:306 drm_dsc_compute_rc_parameters() warn: impossible condition '(vdsc_cfg->nfl_bpg_offset > 65535) => (0-u16max > u16max)' drivers/gpu/drm/drm_dsc.c:340 drm_dsc_compute_rc_parameters() warn: impossible condition '(vdsc_cfg->scale_increment_interval > 65535) => (0-u16max > u16max)' # https://github.com/0day-ci/linux/commit/932e204c9cbe2995451a800351bcd781fa7cb1c5 git remote add linux-review https://github.com/0day-ci/linux git remote update linux-review git checkout 932e204c9cbe2995451a800351bcd781fa7cb1c5 vim +306 drivers/gpu/drm/drm_dsc.c 932e204c David Francis 2019-02-13 230 932e204c David Francis 2019-02-13 231 /** 932e204c David Francis 2019-02-13 232 * drm_dsc_compute_rc_parameters() - Write rate control 932e204c David Francis 2019-02-13 233 * parameters to the dsc configuration. Some configuration 932e204c David Francis 2019-02-13 234 * fields must be present beforehand. 932e204c David Francis 2019-02-13 235 * 932e204c David Francis 2019-02-13 236 * @dsc_cfg: 932e204c David Francis 2019-02-13 237 * DSC Configuration data partially filled by driver 932e204c David Francis 2019-02-13 238 */ 932e204c David Francis 2019-02-13 239 int drm_dsc_compute_rc_parameters(struct drm_dsc_config *vdsc_cfg) 932e204c David Francis 2019-02-13 240 { 932e204c David Francis 2019-02-13 241 unsigned long groups_per_line = 0; 932e204c David Francis 2019-02-13 242 unsigned long groups_total = 0; 932e204c David Francis 2019-02-13 243 unsigned long num_extra_mux_bits = 0; 932e204c David Francis 2019-02-13 244 unsigned long slice_bits = 0; 932e204c David Francis 2019-02-13 245 unsigned long hrd_delay = 0; 932e204c David Francis 2019-02-13 246 unsigned long final_scale = 0; 932e204c David Francis 2019-02-13 247 unsigned long rbs_min = 0; 932e204c David Francis 2019-02-13 248 932e204c David Francis 2019-02-13 249 /* Number of groups used to code each line of a slice */ 932e204c David Francis 2019-02-13 250 groups_per_line = DIV_ROUND_UP(vdsc_cfg->slice_width, 932e204c David Francis 2019-02-13 251 DSC_RC_PIXELS_PER_GROUP); 932e204c David Francis 2019-02-13 252 932e204c David Francis 2019-02-13 253 /* chunksize in Bytes */ 932e204c David Francis 2019-02-13 254 vdsc_cfg->slice_chunk_size = DIV_ROUND_UP(vdsc_cfg->slice_width * 932e204c David Francis 2019-02-13 255 vdsc_cfg->bits_per_pixel, 932e204c David Francis 2019-02-13 256 (8 * 16)); 932e204c David Francis 2019-02-13 257 932e204c David Francis 2019-02-13 258 if (vdsc_cfg->convert_rgb) 932e204c David Francis 2019-02-13 259 num_extra_mux_bits = 3 * (vdsc_cfg->mux_word_size + 932e204c David Francis 2019-02-13 260 (4 * vdsc_cfg->bits_per_component + 4) 932e204c David Francis 2019-02-13 261 - 2); 932e204c David Francis 2019-02-13 262 else 932e204c David Francis 2019-02-13 263 num_extra_mux_bits = 3 * vdsc_cfg->mux_word_size + 932e204c David Francis 2019-02-13 264 (4 * vdsc_cfg->bits_per_component + 4) + 932e204c David Francis 2019-02-13 265 2 * (4 * vdsc_cfg->bits_per_component) - 2; 932e204c David Francis 2019-02-13 266 /* Number of bits in one Slice */ 932e204c David Francis 2019-02-13 267 slice_bits = 8 * vdsc_cfg->slice_chunk_size * vdsc_cfg->slice_height; 932e204c David Francis 2019-02-13 268 932e204c David Francis 2019-02-13 269 while ((num_extra_mux_bits > 0) && 932e204c David Francis 2019-02-13 270 ((slice_bits - num_extra_mux_bits) % vdsc_cfg->mux_word_size)) 932e204c David Francis 2019-02-13 271 num_extra_mux_bits--; 932e204c David Francis 2019-02-13 272 932e204c David Francis 2019-02-13 273 if (groups_per_line < vdsc_cfg->initial_scale_value - 8) 932e204c David Francis 2019-02-13 274 vdsc_cfg->initial_scale_value = groups_per_line + 8; 932e204c David Francis 2019-02-13 275 932e204c David Francis 2019-02-13 276 /* scale_decrement_interval calculation according to DSC spec 1.11 */ 932e204c David Francis 2019-02-13 277 if (vdsc_cfg->initial_scale_value > 8) 932e204c David Francis 2019-02-13 278 vdsc_cfg->scale_decrement_interval = groups_per_line / 932e204c David Francis 2019-02-13 279 (vdsc_cfg->initial_scale_value - 8); 932e204c David Francis 2019-02-13 280 else 932e204c David Francis 2019-02-13 281 vdsc_cfg->scale_decrement_interval = DSC_SCALE_DECREMENT_INTERVAL_MAX; 932e204c David Francis 2019-02-13 282 932e204c David Francis 2019-02-13 283 vdsc_cfg->final_offset = vdsc_cfg->rc_model_size - 932e204c David Francis 2019-02-13 284 (vdsc_cfg->initial_xmit_delay * 932e204c David Francis 2019-02-13 285 vdsc_cfg->bits_per_pixel + 8) / 16 + num_extra_mux_bits; 932e204c David Francis 2019-02-13 286 932e204c David Francis 2019-02-13 287 if (vdsc_cfg->final_offset >= vdsc_cfg->rc_model_size) { 932e204c David Francis 2019-02-13 288 DRM_DEBUG_KMS("FinalOfs < RcModelSze for this InitialXmitDelay\n"); 932e204c David Francis 2019-02-13 289 return -ERANGE; 932e204c David Francis 2019-02-13 290 } 932e204c David Francis 2019-02-13 291 932e204c David Francis 2019-02-13 292 final_scale = (vdsc_cfg->rc_model_size * 8) / 932e204c David Francis 2019-02-13 293 (vdsc_cfg->rc_model_size - vdsc_cfg->final_offset); 932e204c David Francis 2019-02-13 294 if (vdsc_cfg->slice_height > 1) 932e204c David Francis 2019-02-13 295 /* 932e204c David Francis 2019-02-13 296 * NflBpgOffset is 16 bit value with 11 fractional bits 932e204c David Francis 2019-02-13 297 * hence we multiply by 2^11 for preserving the 932e204c David Francis 2019-02-13 298 * fractional part 932e204c David Francis 2019-02-13 299 */ 932e204c David Francis 2019-02-13 300 vdsc_cfg->nfl_bpg_offset = DIV_ROUND_UP((vdsc_cfg->first_line_bpg_offset << 11), 932e204c David Francis 2019-02-13 301 (vdsc_cfg->slice_height - 1)); 932e204c David Francis 2019-02-13 302 else 932e204c David Francis 2019-02-13 303 vdsc_cfg->nfl_bpg_offset = 0; 932e204c David Francis 2019-02-13 304 932e204c David Francis 2019-02-13 305 /* 2^16 - 1 */ 932e204c David Francis 2019-02-13 @306 if (vdsc_cfg->nfl_bpg_offset > 65535) { 932e204c David Francis 2019-02-13 307 DRM_DEBUG_KMS("NflBpgOffset is too large for this slice height\n"); 932e204c David Francis 2019-02-13 308 return -ERANGE; 932e204c David Francis 2019-02-13 309 } 932e204c David Francis 2019-02-13 310 932e204c David Francis 2019-02-13 311 /* Number of groups used to code the entire slice */ 932e204c David Francis 2019-02-13 312 groups_total = groups_per_line * vdsc_cfg->slice_height; 932e204c David Francis 2019-02-13 313 932e204c David Francis 2019-02-13 314 /* slice_bpg_offset is 16 bit value with 11 fractional bits */ 932e204c David Francis 2019-02-13 315 vdsc_cfg->slice_bpg_offset = DIV_ROUND_UP(((vdsc_cfg->rc_model_size - 932e204c David Francis 2019-02-13 316 vdsc_cfg->initial_offset + 932e204c David Francis 2019-02-13 317 num_extra_mux_bits) << 11), 932e204c David Francis 2019-02-13 318 groups_total); 932e204c David Francis 2019-02-13 319 932e204c David Francis 2019-02-13 320 if (final_scale > 9) { 932e204c David Francis 2019-02-13 321 /* 932e204c David Francis 2019-02-13 322 * ScaleIncrementInterval = 932e204c David Francis 2019-02-13 323 * finaloffset/((NflBpgOffset + SliceBpgOffset)*8(finalscale - 1.125)) 932e204c David Francis 2019-02-13 324 * as (NflBpgOffset + SliceBpgOffset) has 11 bit fractional value, 932e204c David Francis 2019-02-13 325 * we need divide by 2^11 from pstDscCfg values 932e204c David Francis 2019-02-13 326 */ 932e204c David Francis 2019-02-13 327 vdsc_cfg->scale_increment_interval = 932e204c David Francis 2019-02-13 328 (vdsc_cfg->final_offset * (1 << 11)) / 932e204c David Francis 2019-02-13 329 ((vdsc_cfg->nfl_bpg_offset + 932e204c David Francis 2019-02-13 330 vdsc_cfg->slice_bpg_offset) * 932e204c David Francis 2019-02-13 331 (final_scale - 9)); 932e204c David Francis 2019-02-13 332 } else { 932e204c David Francis 2019-02-13 333 /* 932e204c David Francis 2019-02-13 334 * If finalScaleValue is less than or equal to 9, a value of 0 should 932e204c David Francis 2019-02-13 335 * be used to disable the scale increment at the end of the slice 932e204c David Francis 2019-02-13 336 */ 932e204c David Francis 2019-02-13 337 vdsc_cfg->scale_increment_interval = 0; 932e204c David Francis 2019-02-13 338 } 932e204c David Francis 2019-02-13 339 932e204c David Francis 2019-02-13 @340 if (vdsc_cfg->scale_increment_interval > 65535) { --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
