1 /*
2 * Copyright 2019 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 * Author: AMD
23 */
24
25 #include <drm/display/drm_dp_helper.h>
26 #include <drm/display/drm_dsc_helper.h>
27 #include "dc_hw_types.h"
28 #include "dsc.h"
29 #include "dc.h"
30 #include "rc_calc.h"
31 #include "fixed31_32.h"
32
33 /* This module's internal functions */
34
35 /* default DSC policy target bitrate limit is 16bpp */
36 static uint32_t dsc_policy_max_target_bpp_limit = 16;
37
38 /* default DSC policy enables DSC only when needed */
39 static bool dsc_policy_enable_dsc_when_not_needed;
40
41 static bool dsc_policy_disable_dsc_stream_overhead;
42
43 #ifndef MAX
44 #define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
45 #endif
46 #ifndef MIN
47 #define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
48 #endif
49
50 /* Forward Declerations */
51 static bool decide_dsc_bandwidth_range(
52 const uint32_t min_bpp_x16,
53 const uint32_t max_bpp_x16,
54 const uint32_t num_slices_h,
55 const struct dsc_enc_caps *dsc_caps,
56 const struct dc_crtc_timing *timing,
57 struct dc_dsc_bw_range *range);
58
59 static uint32_t compute_bpp_x16_from_target_bandwidth(
60 const uint32_t bandwidth_in_kbps,
61 const struct dc_crtc_timing *timing,
62 const uint32_t num_slices_h,
63 const uint32_t bpp_increment_div,
64 const bool is_dp);
65
66 static void get_dsc_enc_caps(
67 const struct display_stream_compressor *dsc,
68 struct dsc_enc_caps *dsc_enc_caps,
69 int pixel_clock_100Hz);
70
71 static bool intersect_dsc_caps(
72 const struct dsc_dec_dpcd_caps *dsc_sink_caps,
73 const struct dsc_enc_caps *dsc_enc_caps,
74 enum dc_pixel_encoding pixel_encoding,
75 struct dsc_enc_caps *dsc_common_caps);
76
77 static bool setup_dsc_config(
78 const struct dsc_dec_dpcd_caps *dsc_sink_caps,
79 const struct dsc_enc_caps *dsc_enc_caps,
80 int target_bandwidth_kbps,
81 const struct dc_crtc_timing *timing,
82 int min_slice_height_override,
83 int max_dsc_target_bpp_limit_override_x16,
84 struct dc_dsc_config *dsc_cfg);
85
dsc_buff_block_size_from_dpcd(int dpcd_buff_block_size,int * buff_block_size)86 static bool dsc_buff_block_size_from_dpcd(int dpcd_buff_block_size, int *buff_block_size)
87 {
88
89 switch (dpcd_buff_block_size) {
90 case DP_DSC_RC_BUF_BLK_SIZE_1:
91 *buff_block_size = 1024;
92 break;
93 case DP_DSC_RC_BUF_BLK_SIZE_4:
94 *buff_block_size = 4 * 1024;
95 break;
96 case DP_DSC_RC_BUF_BLK_SIZE_16:
97 *buff_block_size = 16 * 1024;
98 break;
99 case DP_DSC_RC_BUF_BLK_SIZE_64:
100 *buff_block_size = 64 * 1024;
101 break;
102 default: {
103 dm_error("%s: DPCD DSC buffer size not recognized.\n", __func__);
104 return false;
105 }
106 }
107
108 return true;
109 }
110
111
dsc_line_buff_depth_from_dpcd(int dpcd_line_buff_bit_depth,int * line_buff_bit_depth)112 static bool dsc_line_buff_depth_from_dpcd(int dpcd_line_buff_bit_depth, int *line_buff_bit_depth)
113 {
114 if (0 <= dpcd_line_buff_bit_depth && dpcd_line_buff_bit_depth <= 7)
115 *line_buff_bit_depth = dpcd_line_buff_bit_depth + 9;
116 else if (dpcd_line_buff_bit_depth == 8)
117 *line_buff_bit_depth = 8;
118 else {
119 dm_error("%s: DPCD DSC buffer depth not recognized.\n", __func__);
120 return false;
121 }
122
123 return true;
124 }
125
126
dsc_throughput_from_dpcd(int dpcd_throughput,int * throughput)127 static bool dsc_throughput_from_dpcd(int dpcd_throughput, int *throughput)
128 {
129 switch (dpcd_throughput) {
130 case DP_DSC_THROUGHPUT_MODE_0_UNSUPPORTED:
131 *throughput = 0;
132 break;
133 case DP_DSC_THROUGHPUT_MODE_0_170:
134 *throughput = 170;
135 break;
136 case DP_DSC_THROUGHPUT_MODE_0_340:
137 *throughput = 340;
138 break;
139 case DP_DSC_THROUGHPUT_MODE_0_400:
140 *throughput = 400;
141 break;
142 case DP_DSC_THROUGHPUT_MODE_0_450:
143 *throughput = 450;
144 break;
145 case DP_DSC_THROUGHPUT_MODE_0_500:
146 *throughput = 500;
147 break;
148 case DP_DSC_THROUGHPUT_MODE_0_550:
149 *throughput = 550;
150 break;
151 case DP_DSC_THROUGHPUT_MODE_0_600:
152 *throughput = 600;
153 break;
154 case DP_DSC_THROUGHPUT_MODE_0_650:
155 *throughput = 650;
156 break;
157 case DP_DSC_THROUGHPUT_MODE_0_700:
158 *throughput = 700;
159 break;
160 case DP_DSC_THROUGHPUT_MODE_0_750:
161 *throughput = 750;
162 break;
163 case DP_DSC_THROUGHPUT_MODE_0_800:
164 *throughput = 800;
165 break;
166 case DP_DSC_THROUGHPUT_MODE_0_850:
167 *throughput = 850;
168 break;
169 case DP_DSC_THROUGHPUT_MODE_0_900:
170 *throughput = 900;
171 break;
172 case DP_DSC_THROUGHPUT_MODE_0_950:
173 *throughput = 950;
174 break;
175 case DP_DSC_THROUGHPUT_MODE_0_1000:
176 *throughput = 1000;
177 break;
178 default: {
179 dm_error("%s: DPCD DSC throughput mode not recognized.\n", __func__);
180 return false;
181 }
182 }
183
184 return true;
185 }
186
187
dsc_bpp_increment_div_from_dpcd(uint8_t bpp_increment_dpcd,uint32_t * bpp_increment_div)188 static bool dsc_bpp_increment_div_from_dpcd(uint8_t bpp_increment_dpcd, uint32_t *bpp_increment_div)
189 {
190 // Mask bpp increment dpcd field to avoid reading other fields
191 bpp_increment_dpcd &= 0x7;
192
193 switch (bpp_increment_dpcd) {
194 case 0:
195 *bpp_increment_div = 16;
196 break;
197 case 1:
198 *bpp_increment_div = 8;
199 break;
200 case 2:
201 *bpp_increment_div = 4;
202 break;
203 case 3:
204 *bpp_increment_div = 2;
205 break;
206 case 4:
207 *bpp_increment_div = 1;
208 break;
209 default: {
210 dm_error("%s: DPCD DSC bits-per-pixel increment not recognized.\n", __func__);
211 return false;
212 }
213 }
214
215 return true;
216 }
217
218
219
dc_dsc_parse_dsc_dpcd(const struct dc * dc,const uint8_t * dpcd_dsc_basic_data,const uint8_t * dpcd_dsc_branch_decoder_caps,struct dsc_dec_dpcd_caps * dsc_sink_caps)220 bool dc_dsc_parse_dsc_dpcd(const struct dc *dc,
221 const uint8_t *dpcd_dsc_basic_data,
222 const uint8_t *dpcd_dsc_branch_decoder_caps,
223 struct dsc_dec_dpcd_caps *dsc_sink_caps)
224 {
225 if (!dpcd_dsc_basic_data)
226 return false;
227
228 dsc_sink_caps->is_dsc_supported =
229 (dpcd_dsc_basic_data[DP_DSC_SUPPORT - DP_DSC_SUPPORT] & DP_DSC_DECOMPRESSION_IS_SUPPORTED) != 0;
230 if (!dsc_sink_caps->is_dsc_supported)
231 return false;
232
233 dsc_sink_caps->dsc_version = dpcd_dsc_basic_data[DP_DSC_REV - DP_DSC_SUPPORT];
234
235 {
236 int buff_block_size;
237 int buff_size;
238
239 if (!dsc_buff_block_size_from_dpcd(dpcd_dsc_basic_data[DP_DSC_RC_BUF_BLK_SIZE - DP_DSC_SUPPORT],
240 &buff_block_size))
241 return false;
242
243 buff_size = dpcd_dsc_basic_data[DP_DSC_RC_BUF_SIZE - DP_DSC_SUPPORT] + 1;
244 dsc_sink_caps->rc_buffer_size = buff_size * buff_block_size;
245 }
246
247 dsc_sink_caps->slice_caps1.raw = dpcd_dsc_basic_data[DP_DSC_SLICE_CAP_1 - DP_DSC_SUPPORT];
248 if (!dsc_line_buff_depth_from_dpcd(dpcd_dsc_basic_data[DP_DSC_LINE_BUF_BIT_DEPTH - DP_DSC_SUPPORT],
249 &dsc_sink_caps->lb_bit_depth))
250 return false;
251
252 dsc_sink_caps->is_block_pred_supported =
253 (dpcd_dsc_basic_data[DP_DSC_BLK_PREDICTION_SUPPORT - DP_DSC_SUPPORT] &
254 DP_DSC_BLK_PREDICTION_IS_SUPPORTED) != 0;
255
256 dsc_sink_caps->edp_max_bits_per_pixel =
257 dpcd_dsc_basic_data[DP_DSC_MAX_BITS_PER_PIXEL_LOW - DP_DSC_SUPPORT] |
258 dpcd_dsc_basic_data[DP_DSC_MAX_BITS_PER_PIXEL_HI - DP_DSC_SUPPORT] << 8;
259
260 dsc_sink_caps->color_formats.raw = dpcd_dsc_basic_data[DP_DSC_DEC_COLOR_FORMAT_CAP - DP_DSC_SUPPORT];
261 dsc_sink_caps->color_depth.raw = dpcd_dsc_basic_data[DP_DSC_DEC_COLOR_DEPTH_CAP - DP_DSC_SUPPORT];
262
263 {
264 int dpcd_throughput = dpcd_dsc_basic_data[DP_DSC_PEAK_THROUGHPUT - DP_DSC_SUPPORT];
265
266 if (!dsc_throughput_from_dpcd(dpcd_throughput & DP_DSC_THROUGHPUT_MODE_0_MASK,
267 &dsc_sink_caps->throughput_mode_0_mps))
268 return false;
269
270 dpcd_throughput = (dpcd_throughput & DP_DSC_THROUGHPUT_MODE_1_MASK) >> DP_DSC_THROUGHPUT_MODE_1_SHIFT;
271 if (!dsc_throughput_from_dpcd(dpcd_throughput, &dsc_sink_caps->throughput_mode_1_mps))
272 return false;
273 }
274
275 dsc_sink_caps->max_slice_width = dpcd_dsc_basic_data[DP_DSC_MAX_SLICE_WIDTH - DP_DSC_SUPPORT] * 320;
276 dsc_sink_caps->slice_caps2.raw = dpcd_dsc_basic_data[DP_DSC_SLICE_CAP_2 - DP_DSC_SUPPORT];
277
278 if (!dsc_bpp_increment_div_from_dpcd(dpcd_dsc_basic_data[DP_DSC_BITS_PER_PIXEL_INC - DP_DSC_SUPPORT],
279 &dsc_sink_caps->bpp_increment_div))
280 return false;
281
282 if (dc->debug.dsc_bpp_increment_div) {
283 /* dsc_bpp_increment_div should onl be 1, 2, 4, 8 or 16, but rather than rejecting invalid values,
284 * we'll accept all and get it into range. This also makes the above check against 0 redundant,
285 * but that one stresses out the override will be only used if it's not 0.
286 */
287 if (dc->debug.dsc_bpp_increment_div >= 1)
288 dsc_sink_caps->bpp_increment_div = 1;
289 if (dc->debug.dsc_bpp_increment_div >= 2)
290 dsc_sink_caps->bpp_increment_div = 2;
291 if (dc->debug.dsc_bpp_increment_div >= 4)
292 dsc_sink_caps->bpp_increment_div = 4;
293 if (dc->debug.dsc_bpp_increment_div >= 8)
294 dsc_sink_caps->bpp_increment_div = 8;
295 if (dc->debug.dsc_bpp_increment_div >= 16)
296 dsc_sink_caps->bpp_increment_div = 16;
297 }
298
299 /* Extended caps */
300 if (dpcd_dsc_branch_decoder_caps == NULL) { // branch decoder DPCD DSC data can be null for non branch device
301 dsc_sink_caps->branch_overall_throughput_0_mps = 0;
302 dsc_sink_caps->branch_overall_throughput_1_mps = 0;
303 dsc_sink_caps->branch_max_line_width = 0;
304 return true;
305 }
306
307 dsc_sink_caps->branch_overall_throughput_0_mps =
308 dpcd_dsc_branch_decoder_caps[DP_DSC_BRANCH_OVERALL_THROUGHPUT_0 - DP_DSC_BRANCH_OVERALL_THROUGHPUT_0];
309 if (dsc_sink_caps->branch_overall_throughput_0_mps == 0)
310 dsc_sink_caps->branch_overall_throughput_0_mps = 0;
311 else if (dsc_sink_caps->branch_overall_throughput_0_mps == 1)
312 dsc_sink_caps->branch_overall_throughput_0_mps = 680;
313 else {
314 dsc_sink_caps->branch_overall_throughput_0_mps *= 50;
315 dsc_sink_caps->branch_overall_throughput_0_mps += 600;
316 }
317
318 dsc_sink_caps->branch_overall_throughput_1_mps =
319 dpcd_dsc_branch_decoder_caps[DP_DSC_BRANCH_OVERALL_THROUGHPUT_1 - DP_DSC_BRANCH_OVERALL_THROUGHPUT_0];
320 if (dsc_sink_caps->branch_overall_throughput_1_mps == 0)
321 dsc_sink_caps->branch_overall_throughput_1_mps = 0;
322 else if (dsc_sink_caps->branch_overall_throughput_1_mps == 1)
323 dsc_sink_caps->branch_overall_throughput_1_mps = 680;
324 else {
325 dsc_sink_caps->branch_overall_throughput_1_mps *= 50;
326 dsc_sink_caps->branch_overall_throughput_1_mps += 600;
327 }
328
329 dsc_sink_caps->branch_max_line_width =
330 dpcd_dsc_branch_decoder_caps[DP_DSC_BRANCH_MAX_LINE_WIDTH - DP_DSC_BRANCH_OVERALL_THROUGHPUT_0] * 320;
331 ASSERT(dsc_sink_caps->branch_max_line_width == 0 || dsc_sink_caps->branch_max_line_width >= 5120);
332
333 dsc_sink_caps->is_dp = true;
334 return true;
335 }
336
337
338 /* If DSC is possbile, get DSC bandwidth range based on [min_bpp, max_bpp] target bitrate range and
339 * timing's pixel clock and uncompressed bandwidth.
340 * If DSC is not possible, leave '*range' untouched.
341 */
dc_dsc_compute_bandwidth_range(const struct display_stream_compressor * dsc,uint32_t dsc_min_slice_height_override,uint32_t min_bpp_x16,uint32_t max_bpp_x16,const struct dsc_dec_dpcd_caps * dsc_sink_caps,const struct dc_crtc_timing * timing,struct dc_dsc_bw_range * range)342 bool dc_dsc_compute_bandwidth_range(
343 const struct display_stream_compressor *dsc,
344 uint32_t dsc_min_slice_height_override,
345 uint32_t min_bpp_x16,
346 uint32_t max_bpp_x16,
347 const struct dsc_dec_dpcd_caps *dsc_sink_caps,
348 const struct dc_crtc_timing *timing,
349 struct dc_dsc_bw_range *range)
350 {
351 bool is_dsc_possible = false;
352 struct dsc_enc_caps dsc_enc_caps;
353 struct dsc_enc_caps dsc_common_caps;
354 struct dc_dsc_config config;
355
356 get_dsc_enc_caps(dsc, &dsc_enc_caps, timing->pix_clk_100hz);
357
358 is_dsc_possible = intersect_dsc_caps(dsc_sink_caps, &dsc_enc_caps,
359 timing->pixel_encoding, &dsc_common_caps);
360
361 if (is_dsc_possible)
362 is_dsc_possible = setup_dsc_config(dsc_sink_caps, &dsc_enc_caps, 0, timing,
363 dsc_min_slice_height_override, max_bpp_x16, &config);
364
365 if (is_dsc_possible)
366 is_dsc_possible = decide_dsc_bandwidth_range(min_bpp_x16, max_bpp_x16,
367 config.num_slices_h, &dsc_common_caps, timing, range);
368
369 return is_dsc_possible;
370 }
371
get_dsc_enc_caps(const struct display_stream_compressor * dsc,struct dsc_enc_caps * dsc_enc_caps,int pixel_clock_100Hz)372 static void get_dsc_enc_caps(
373 const struct display_stream_compressor *dsc,
374 struct dsc_enc_caps *dsc_enc_caps,
375 int pixel_clock_100Hz)
376 {
377 // This is a static HW query, so we can use any DSC
378
379 memset(dsc_enc_caps, 0, sizeof(struct dsc_enc_caps));
380 if (dsc) {
381 if (!dsc->ctx->dc->debug.disable_dsc)
382 dsc->funcs->dsc_get_enc_caps(dsc_enc_caps, pixel_clock_100Hz);
383 if (dsc->ctx->dc->debug.native422_support)
384 dsc_enc_caps->color_formats.bits.YCBCR_NATIVE_422 = 1;
385 }
386 }
387
388 /* Returns 'false' if no intersection was found for at least one capability.
389 * It also implicitly validates some sink caps against invalid value of zero.
390 */
intersect_dsc_caps(const struct dsc_dec_dpcd_caps * dsc_sink_caps,const struct dsc_enc_caps * dsc_enc_caps,enum dc_pixel_encoding pixel_encoding,struct dsc_enc_caps * dsc_common_caps)391 static bool intersect_dsc_caps(
392 const struct dsc_dec_dpcd_caps *dsc_sink_caps,
393 const struct dsc_enc_caps *dsc_enc_caps,
394 enum dc_pixel_encoding pixel_encoding,
395 struct dsc_enc_caps *dsc_common_caps)
396 {
397 int32_t max_slices;
398 int32_t total_sink_throughput;
399
400 memset(dsc_common_caps, 0, sizeof(struct dsc_enc_caps));
401
402 dsc_common_caps->dsc_version = min(dsc_sink_caps->dsc_version, dsc_enc_caps->dsc_version);
403 if (!dsc_common_caps->dsc_version)
404 return false;
405
406 dsc_common_caps->slice_caps.bits.NUM_SLICES_1 =
407 dsc_sink_caps->slice_caps1.bits.NUM_SLICES_1 && dsc_enc_caps->slice_caps.bits.NUM_SLICES_1;
408 dsc_common_caps->slice_caps.bits.NUM_SLICES_2 =
409 dsc_sink_caps->slice_caps1.bits.NUM_SLICES_2 && dsc_enc_caps->slice_caps.bits.NUM_SLICES_2;
410 dsc_common_caps->slice_caps.bits.NUM_SLICES_4 =
411 dsc_sink_caps->slice_caps1.bits.NUM_SLICES_4 && dsc_enc_caps->slice_caps.bits.NUM_SLICES_4;
412 dsc_common_caps->slice_caps.bits.NUM_SLICES_8 =
413 dsc_sink_caps->slice_caps1.bits.NUM_SLICES_8 && dsc_enc_caps->slice_caps.bits.NUM_SLICES_8;
414 if (!dsc_common_caps->slice_caps.raw)
415 return false;
416
417 dsc_common_caps->lb_bit_depth = min(dsc_sink_caps->lb_bit_depth, dsc_enc_caps->lb_bit_depth);
418 if (!dsc_common_caps->lb_bit_depth)
419 return false;
420
421 dsc_common_caps->is_block_pred_supported =
422 dsc_sink_caps->is_block_pred_supported && dsc_enc_caps->is_block_pred_supported;
423
424 dsc_common_caps->color_formats.raw = dsc_sink_caps->color_formats.raw & dsc_enc_caps->color_formats.raw;
425 if (!dsc_common_caps->color_formats.raw)
426 return false;
427
428 dsc_common_caps->color_depth.raw = dsc_sink_caps->color_depth.raw & dsc_enc_caps->color_depth.raw;
429 if (!dsc_common_caps->color_depth.raw)
430 return false;
431
432 max_slices = 0;
433 if (dsc_common_caps->slice_caps.bits.NUM_SLICES_1)
434 max_slices = 1;
435
436 if (dsc_common_caps->slice_caps.bits.NUM_SLICES_2)
437 max_slices = 2;
438
439 if (dsc_common_caps->slice_caps.bits.NUM_SLICES_4)
440 max_slices = 4;
441
442 total_sink_throughput = max_slices * dsc_sink_caps->throughput_mode_0_mps;
443 if (pixel_encoding == PIXEL_ENCODING_YCBCR422 || pixel_encoding == PIXEL_ENCODING_YCBCR420)
444 total_sink_throughput = max_slices * dsc_sink_caps->throughput_mode_1_mps;
445
446 dsc_common_caps->max_total_throughput_mps = min(total_sink_throughput, dsc_enc_caps->max_total_throughput_mps);
447
448 dsc_common_caps->max_slice_width = min(dsc_sink_caps->max_slice_width, dsc_enc_caps->max_slice_width);
449 if (!dsc_common_caps->max_slice_width)
450 return false;
451
452 dsc_common_caps->bpp_increment_div = min(dsc_sink_caps->bpp_increment_div, dsc_enc_caps->bpp_increment_div);
453
454 // TODO DSC: Remove this workaround for N422 and 420 once it's fixed, or move it to get_dsc_encoder_caps()
455 if (pixel_encoding == PIXEL_ENCODING_YCBCR422 || pixel_encoding == PIXEL_ENCODING_YCBCR420)
456 dsc_common_caps->bpp_increment_div = min(dsc_common_caps->bpp_increment_div, (uint32_t)8);
457
458 dsc_common_caps->edp_sink_max_bits_per_pixel = dsc_sink_caps->edp_max_bits_per_pixel;
459 dsc_common_caps->is_dp = dsc_sink_caps->is_dp;
460 return true;
461 }
462
dsc_div_by_10_round_up(uint32_t value)463 static inline uint32_t dsc_div_by_10_round_up(uint32_t value)
464 {
465 return (value + 9) / 10;
466 }
467
compute_bpp_x16_from_target_bandwidth(const uint32_t bandwidth_in_kbps,const struct dc_crtc_timing * timing,const uint32_t num_slices_h,const uint32_t bpp_increment_div,const bool is_dp)468 static uint32_t compute_bpp_x16_from_target_bandwidth(
469 const uint32_t bandwidth_in_kbps,
470 const struct dc_crtc_timing *timing,
471 const uint32_t num_slices_h,
472 const uint32_t bpp_increment_div,
473 const bool is_dp)
474 {
475 uint32_t overhead_in_kbps;
476 struct fixed31_32 effective_bandwidth_in_kbps;
477 struct fixed31_32 bpp_x16;
478
479 overhead_in_kbps = dc_dsc_stream_bandwidth_overhead_in_kbps(
480 timing, num_slices_h, is_dp);
481 effective_bandwidth_in_kbps = dc_fixpt_from_int(bandwidth_in_kbps);
482 effective_bandwidth_in_kbps = dc_fixpt_sub_int(effective_bandwidth_in_kbps,
483 overhead_in_kbps);
484 bpp_x16 = dc_fixpt_mul_int(effective_bandwidth_in_kbps, 10);
485 bpp_x16 = dc_fixpt_div_int(bpp_x16, timing->pix_clk_100hz);
486 bpp_x16 = dc_fixpt_from_int(dc_fixpt_floor(dc_fixpt_mul_int(bpp_x16, bpp_increment_div)));
487 bpp_x16 = dc_fixpt_div_int(bpp_x16, bpp_increment_div);
488 bpp_x16 = dc_fixpt_mul_int(bpp_x16, 16);
489 return dc_fixpt_floor(bpp_x16);
490 }
491
492 /* Decide DSC bandwidth range based on signal, timing, specs specific and input min and max
493 * requirements.
494 * The range output includes decided min/max target bpp, the respective bandwidth requirements
495 * and native timing bandwidth requirement when DSC is not used.
496 */
decide_dsc_bandwidth_range(const uint32_t min_bpp_x16,const uint32_t max_bpp_x16,const uint32_t num_slices_h,const struct dsc_enc_caps * dsc_caps,const struct dc_crtc_timing * timing,struct dc_dsc_bw_range * range)497 static bool decide_dsc_bandwidth_range(
498 const uint32_t min_bpp_x16,
499 const uint32_t max_bpp_x16,
500 const uint32_t num_slices_h,
501 const struct dsc_enc_caps *dsc_caps,
502 const struct dc_crtc_timing *timing,
503 struct dc_dsc_bw_range *range)
504 {
505 uint32_t preferred_bpp_x16 = timing->dsc_fixed_bits_per_pixel_x16;
506
507 memset(range, 0, sizeof(*range));
508
509 /* apply signal, timing, specs and explicitly specified DSC range requirements */
510 if (preferred_bpp_x16) {
511 if (preferred_bpp_x16 <= max_bpp_x16 &&
512 preferred_bpp_x16 >= min_bpp_x16) {
513 range->max_target_bpp_x16 = preferred_bpp_x16;
514 range->min_target_bpp_x16 = preferred_bpp_x16;
515 }
516 }
517 /* TODO - make this value generic to all signal types */
518 else if (dsc_caps->edp_sink_max_bits_per_pixel) {
519 /* apply max bpp limitation from edp sink */
520 range->max_target_bpp_x16 = MIN(dsc_caps->edp_sink_max_bits_per_pixel,
521 max_bpp_x16);
522 range->min_target_bpp_x16 = min_bpp_x16;
523 }
524 else {
525 range->max_target_bpp_x16 = max_bpp_x16;
526 range->min_target_bpp_x16 = min_bpp_x16;
527 }
528
529 /* populate output structure */
530 if (range->max_target_bpp_x16 >= range->min_target_bpp_x16 && range->min_target_bpp_x16 > 0) {
531 /* native stream bandwidth */
532 range->stream_kbps = dc_bandwidth_in_kbps_from_timing(timing);
533
534 /* max dsc target bpp */
535 range->max_kbps = dc_dsc_stream_bandwidth_in_kbps(timing,
536 range->max_target_bpp_x16, num_slices_h, dsc_caps->is_dp);
537
538 /* min dsc target bpp */
539 range->min_kbps = dc_dsc_stream_bandwidth_in_kbps(timing,
540 range->min_target_bpp_x16, num_slices_h, dsc_caps->is_dp);
541 }
542
543 return range->max_kbps >= range->min_kbps && range->min_kbps > 0;
544 }
545
546 /* Decides if DSC should be used and calculates target bpp if it should, applying DSC policy.
547 *
548 * Returns:
549 * - 'true' if target bpp is decided
550 * - 'false' if target bpp cannot be decided (e.g. cannot fit even with min DSC bpp),
551 */
decide_dsc_target_bpp_x16(const struct dc_dsc_policy * policy,const struct dsc_enc_caps * dsc_common_caps,const int target_bandwidth_kbps,const struct dc_crtc_timing * timing,const int num_slices_h,int * target_bpp_x16)552 static bool decide_dsc_target_bpp_x16(
553 const struct dc_dsc_policy *policy,
554 const struct dsc_enc_caps *dsc_common_caps,
555 const int target_bandwidth_kbps,
556 const struct dc_crtc_timing *timing,
557 const int num_slices_h,
558 int *target_bpp_x16)
559 {
560 struct dc_dsc_bw_range range;
561
562 *target_bpp_x16 = 0;
563
564 if (decide_dsc_bandwidth_range(policy->min_target_bpp * 16, policy->max_target_bpp * 16,
565 num_slices_h, dsc_common_caps, timing, &range)) {
566 if (target_bandwidth_kbps >= range.stream_kbps) {
567 if (policy->enable_dsc_when_not_needed)
568 /* enable max bpp even dsc is not needed */
569 *target_bpp_x16 = range.max_target_bpp_x16;
570 } else if (target_bandwidth_kbps >= range.max_kbps) {
571 /* use max target bpp allowed */
572 *target_bpp_x16 = range.max_target_bpp_x16;
573 } else if (target_bandwidth_kbps >= range.min_kbps) {
574 /* use target bpp that can take entire target bandwidth */
575 *target_bpp_x16 = compute_bpp_x16_from_target_bandwidth(
576 target_bandwidth_kbps, timing, num_slices_h,
577 dsc_common_caps->bpp_increment_div,
578 dsc_common_caps->is_dp);
579 }
580 }
581
582 return *target_bpp_x16 != 0;
583 }
584
585 #define MIN_AVAILABLE_SLICES_SIZE 6
586
get_available_dsc_slices(union dsc_enc_slice_caps slice_caps,int * available_slices)587 static int get_available_dsc_slices(union dsc_enc_slice_caps slice_caps, int *available_slices)
588 {
589 int idx = 0;
590
591 memset(available_slices, -1, MIN_AVAILABLE_SLICES_SIZE);
592
593 if (slice_caps.bits.NUM_SLICES_1)
594 available_slices[idx++] = 1;
595
596 if (slice_caps.bits.NUM_SLICES_2)
597 available_slices[idx++] = 2;
598
599 if (slice_caps.bits.NUM_SLICES_4)
600 available_slices[idx++] = 4;
601
602 if (slice_caps.bits.NUM_SLICES_8)
603 available_slices[idx++] = 8;
604
605 return idx;
606 }
607
608
get_max_dsc_slices(union dsc_enc_slice_caps slice_caps)609 static int get_max_dsc_slices(union dsc_enc_slice_caps slice_caps)
610 {
611 int max_slices = 0;
612 int available_slices[MIN_AVAILABLE_SLICES_SIZE];
613 int end_idx = get_available_dsc_slices(slice_caps, &available_slices[0]);
614
615 if (end_idx > 0)
616 max_slices = available_slices[end_idx - 1];
617
618 return max_slices;
619 }
620
621
622 // Increment slice number in available slice numbers stops if possible, or just increment if not
inc_num_slices(union dsc_enc_slice_caps slice_caps,int num_slices)623 static int inc_num_slices(union dsc_enc_slice_caps slice_caps, int num_slices)
624 {
625 // Get next bigger num slices available in common caps
626 int available_slices[MIN_AVAILABLE_SLICES_SIZE];
627 int end_idx;
628 int i;
629 int new_num_slices = num_slices;
630
631 end_idx = get_available_dsc_slices(slice_caps, &available_slices[0]);
632 if (end_idx == 0) {
633 // No available slices found
634 new_num_slices++;
635 return new_num_slices;
636 }
637
638 // Numbers of slices found - get the next bigger number
639 for (i = 0; i < end_idx; i++) {
640 if (new_num_slices < available_slices[i]) {
641 new_num_slices = available_slices[i];
642 break;
643 }
644 }
645
646 if (new_num_slices == num_slices) // No biger number of slices found
647 new_num_slices++;
648
649 return new_num_slices;
650 }
651
652
653 // Decrement slice number in available slice numbers stops if possible, or just decrement if not. Stop at zero.
dec_num_slices(union dsc_enc_slice_caps slice_caps,int num_slices)654 static int dec_num_slices(union dsc_enc_slice_caps slice_caps, int num_slices)
655 {
656 // Get next bigger num slices available in common caps
657 int available_slices[MIN_AVAILABLE_SLICES_SIZE];
658 int end_idx;
659 int i;
660 int new_num_slices = num_slices;
661
662 end_idx = get_available_dsc_slices(slice_caps, &available_slices[0]);
663 if (end_idx == 0 && new_num_slices > 0) {
664 // No numbers of slices found
665 new_num_slices++;
666 return new_num_slices;
667 }
668
669 // Numbers of slices found - get the next smaller number
670 for (i = end_idx - 1; i >= 0; i--) {
671 if (new_num_slices > available_slices[i]) {
672 new_num_slices = available_slices[i];
673 break;
674 }
675 }
676
677 if (new_num_slices == num_slices) {
678 // No smaller number of slices found
679 new_num_slices--;
680 if (new_num_slices < 0)
681 new_num_slices = 0;
682 }
683
684 return new_num_slices;
685 }
686
687
688 // Choose next bigger number of slices if the requested number of slices is not available
fit_num_slices_up(union dsc_enc_slice_caps slice_caps,int num_slices)689 static int fit_num_slices_up(union dsc_enc_slice_caps slice_caps, int num_slices)
690 {
691 // Get next bigger num slices available in common caps
692 int available_slices[MIN_AVAILABLE_SLICES_SIZE];
693 int end_idx;
694 int i;
695 int new_num_slices = num_slices;
696
697 end_idx = get_available_dsc_slices(slice_caps, &available_slices[0]);
698 if (end_idx == 0) {
699 // No available slices found
700 new_num_slices++;
701 return new_num_slices;
702 }
703
704 // Numbers of slices found - get the equal or next bigger number
705 for (i = 0; i < end_idx; i++) {
706 if (new_num_slices <= available_slices[i]) {
707 new_num_slices = available_slices[i];
708 break;
709 }
710 }
711
712 return new_num_slices;
713 }
714
715
716 /* Attempts to set DSC configuration for the stream, applying DSC policy.
717 * Returns 'true' if successful or 'false' if not.
718 *
719 * Parameters:
720 *
721 * dsc_sink_caps - DSC sink decoder capabilities (from DPCD)
722 *
723 * dsc_enc_caps - DSC encoder capabilities
724 *
725 * target_bandwidth_kbps - Target bandwidth to fit the stream into.
726 * If 0, do not calculate target bpp.
727 *
728 * timing - The stream timing to fit into 'target_bandwidth_kbps' or apply
729 * maximum compression to, if 'target_badwidth == 0'
730 *
731 * dsc_cfg - DSC configuration to use if it was possible to come up with
732 * one for the given inputs.
733 * The target bitrate after DSC can be calculated by multiplying
734 * dsc_cfg.bits_per_pixel (in U6.4 format) by pixel rate, e.g.
735 *
736 * dsc_stream_bitrate_kbps = (int)ceil(timing->pix_clk_khz * dsc_cfg.bits_per_pixel / 16.0);
737 */
setup_dsc_config(const struct dsc_dec_dpcd_caps * dsc_sink_caps,const struct dsc_enc_caps * dsc_enc_caps,int target_bandwidth_kbps,const struct dc_crtc_timing * timing,int min_slice_height_override,int max_dsc_target_bpp_limit_override_x16,struct dc_dsc_config * dsc_cfg)738 static bool setup_dsc_config(
739 const struct dsc_dec_dpcd_caps *dsc_sink_caps,
740 const struct dsc_enc_caps *dsc_enc_caps,
741 int target_bandwidth_kbps,
742 const struct dc_crtc_timing *timing,
743 int min_slice_height_override,
744 int max_dsc_target_bpp_limit_override_x16,
745 struct dc_dsc_config *dsc_cfg)
746 {
747 struct dsc_enc_caps dsc_common_caps;
748 int max_slices_h;
749 int min_slices_h;
750 int num_slices_h;
751 int pic_width;
752 int slice_width;
753 int target_bpp;
754 int sink_per_slice_throughput_mps;
755 int branch_max_throughput_mps = 0;
756 bool is_dsc_possible = false;
757 int pic_height;
758 int slice_height;
759 struct dc_dsc_policy policy;
760
761 memset(dsc_cfg, 0, sizeof(struct dc_dsc_config));
762
763 dc_dsc_get_policy_for_timing(timing, max_dsc_target_bpp_limit_override_x16, &policy);
764 pic_width = timing->h_addressable + timing->h_border_left + timing->h_border_right;
765 pic_height = timing->v_addressable + timing->v_border_top + timing->v_border_bottom;
766
767 if (!dsc_sink_caps->is_dsc_supported)
768 goto done;
769
770 if (dsc_sink_caps->branch_max_line_width && dsc_sink_caps->branch_max_line_width < pic_width)
771 goto done;
772
773 // Intersect decoder with encoder DSC caps and validate DSC settings
774 is_dsc_possible = intersect_dsc_caps(dsc_sink_caps, dsc_enc_caps, timing->pixel_encoding, &dsc_common_caps);
775 if (!is_dsc_possible)
776 goto done;
777
778 sink_per_slice_throughput_mps = 0;
779
780 // Validate available DSC settings against the mode timing
781
782 // Validate color format (and pick up the throughput values)
783 dsc_cfg->ycbcr422_simple = false;
784 switch (timing->pixel_encoding) {
785 case PIXEL_ENCODING_RGB:
786 is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.RGB;
787 sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_0_mps;
788 branch_max_throughput_mps = dsc_sink_caps->branch_overall_throughput_0_mps;
789 break;
790 case PIXEL_ENCODING_YCBCR444:
791 is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.YCBCR_444;
792 sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_0_mps;
793 branch_max_throughput_mps = dsc_sink_caps->branch_overall_throughput_0_mps;
794 break;
795 case PIXEL_ENCODING_YCBCR422:
796 is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.YCBCR_NATIVE_422;
797 sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_1_mps;
798 branch_max_throughput_mps = dsc_sink_caps->branch_overall_throughput_1_mps;
799 if (!is_dsc_possible) {
800 is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.YCBCR_SIMPLE_422;
801 dsc_cfg->ycbcr422_simple = is_dsc_possible;
802 sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_0_mps;
803 }
804 break;
805 case PIXEL_ENCODING_YCBCR420:
806 is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.YCBCR_NATIVE_420;
807 sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_1_mps;
808 branch_max_throughput_mps = dsc_sink_caps->branch_overall_throughput_1_mps;
809 break;
810 default:
811 is_dsc_possible = false;
812 }
813
814 // Validate branch's maximum throughput
815 if (branch_max_throughput_mps && dsc_div_by_10_round_up(timing->pix_clk_100hz) > branch_max_throughput_mps * 1000)
816 is_dsc_possible = false;
817
818 if (!is_dsc_possible)
819 goto done;
820
821 // Color depth
822 switch (timing->display_color_depth) {
823 case COLOR_DEPTH_888:
824 is_dsc_possible = (bool)dsc_common_caps.color_depth.bits.COLOR_DEPTH_8_BPC;
825 break;
826 case COLOR_DEPTH_101010:
827 is_dsc_possible = (bool)dsc_common_caps.color_depth.bits.COLOR_DEPTH_10_BPC;
828 break;
829 case COLOR_DEPTH_121212:
830 is_dsc_possible = (bool)dsc_common_caps.color_depth.bits.COLOR_DEPTH_12_BPC;
831 break;
832 default:
833 is_dsc_possible = false;
834 }
835
836 if (!is_dsc_possible)
837 goto done;
838
839 // Slice width (i.e. number of slices per line)
840 max_slices_h = get_max_dsc_slices(dsc_common_caps.slice_caps);
841
842 while (max_slices_h > 0) {
843 if (pic_width % max_slices_h == 0)
844 break;
845
846 max_slices_h = dec_num_slices(dsc_common_caps.slice_caps, max_slices_h);
847 }
848
849 is_dsc_possible = (dsc_common_caps.max_slice_width > 0);
850 if (!is_dsc_possible)
851 goto done;
852
853 min_slices_h = pic_width / dsc_common_caps.max_slice_width;
854 if (pic_width % dsc_common_caps.max_slice_width)
855 min_slices_h++;
856
857 min_slices_h = fit_num_slices_up(dsc_common_caps.slice_caps, min_slices_h);
858
859 while (min_slices_h <= max_slices_h) {
860 int pix_clk_per_slice_khz = dsc_div_by_10_round_up(timing->pix_clk_100hz) / min_slices_h;
861 if (pix_clk_per_slice_khz <= sink_per_slice_throughput_mps * 1000)
862 break;
863
864 min_slices_h = inc_num_slices(dsc_common_caps.slice_caps, min_slices_h);
865 }
866
867 is_dsc_possible = (min_slices_h <= max_slices_h);
868
869 if (pic_width % min_slices_h != 0)
870 min_slices_h = 0; // DSC TODO: Maybe try increasing the number of slices first?
871
872 if (min_slices_h == 0 && max_slices_h == 0)
873 is_dsc_possible = false;
874
875 if (!is_dsc_possible)
876 goto done;
877
878 if (policy.use_min_slices_h) {
879 if (min_slices_h > 0)
880 num_slices_h = min_slices_h;
881 else if (max_slices_h > 0) { // Fall back to max slices if min slices is not working out
882 if (policy.max_slices_h)
883 num_slices_h = min(policy.max_slices_h, max_slices_h);
884 else
885 num_slices_h = max_slices_h;
886 } else
887 is_dsc_possible = false;
888 } else {
889 if (max_slices_h > 0) {
890 if (policy.max_slices_h)
891 num_slices_h = min(policy.max_slices_h, max_slices_h);
892 else
893 num_slices_h = max_slices_h;
894 } else if (min_slices_h > 0) // Fall back to min slices if max slices is not possible
895 num_slices_h = min_slices_h;
896 else
897 is_dsc_possible = false;
898 }
899
900 if (!is_dsc_possible)
901 goto done;
902
903 dsc_cfg->num_slices_h = num_slices_h;
904 slice_width = pic_width / num_slices_h;
905
906 is_dsc_possible = slice_width <= dsc_common_caps.max_slice_width;
907 if (!is_dsc_possible)
908 goto done;
909
910 // Slice height (i.e. number of slices per column): start with policy and pick the first one that height is divisible by.
911 // For 4:2:0 make sure the slice height is divisible by 2 as well.
912 if (min_slice_height_override == 0)
913 slice_height = min(policy.min_slice_height, pic_height);
914 else
915 slice_height = min(min_slice_height_override, pic_height);
916
917 while (slice_height < pic_height && (pic_height % slice_height != 0 ||
918 (timing->pixel_encoding == PIXEL_ENCODING_YCBCR420 && slice_height % 2 != 0)))
919 slice_height++;
920
921 if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR420) // For the case when pic_height < dsc_policy.min_sice_height
922 is_dsc_possible = (slice_height % 2 == 0);
923
924 if (!is_dsc_possible)
925 goto done;
926
927 dsc_cfg->num_slices_v = pic_height/slice_height;
928
929 if (target_bandwidth_kbps > 0) {
930 is_dsc_possible = decide_dsc_target_bpp_x16(
931 &policy,
932 &dsc_common_caps,
933 target_bandwidth_kbps,
934 timing,
935 num_slices_h,
936 &target_bpp);
937 dsc_cfg->bits_per_pixel = target_bpp;
938 }
939 if (!is_dsc_possible)
940 goto done;
941
942 // Final decission: can we do DSC or not?
943 if (is_dsc_possible) {
944 // Fill out the rest of DSC settings
945 dsc_cfg->block_pred_enable = dsc_common_caps.is_block_pred_supported;
946 dsc_cfg->linebuf_depth = dsc_common_caps.lb_bit_depth;
947 dsc_cfg->version_minor = (dsc_common_caps.dsc_version & 0xf0) >> 4;
948 dsc_cfg->is_dp = dsc_sink_caps->is_dp;
949 }
950
951 done:
952 if (!is_dsc_possible)
953 memset(dsc_cfg, 0, sizeof(struct dc_dsc_config));
954
955 return is_dsc_possible;
956 }
957
dc_dsc_compute_config(const struct display_stream_compressor * dsc,const struct dsc_dec_dpcd_caps * dsc_sink_caps,uint32_t dsc_min_slice_height_override,uint32_t max_target_bpp_limit_override,uint32_t target_bandwidth_kbps,const struct dc_crtc_timing * timing,struct dc_dsc_config * dsc_cfg)958 bool dc_dsc_compute_config(
959 const struct display_stream_compressor *dsc,
960 const struct dsc_dec_dpcd_caps *dsc_sink_caps,
961 uint32_t dsc_min_slice_height_override,
962 uint32_t max_target_bpp_limit_override,
963 uint32_t target_bandwidth_kbps,
964 const struct dc_crtc_timing *timing,
965 struct dc_dsc_config *dsc_cfg)
966 {
967 bool is_dsc_possible = false;
968 struct dsc_enc_caps dsc_enc_caps;
969
970 get_dsc_enc_caps(dsc, &dsc_enc_caps, timing->pix_clk_100hz);
971 is_dsc_possible = setup_dsc_config(dsc_sink_caps,
972 &dsc_enc_caps,
973 target_bandwidth_kbps,
974 timing, dsc_min_slice_height_override,
975 max_target_bpp_limit_override * 16, dsc_cfg);
976 return is_dsc_possible;
977 }
978
dc_dsc_stream_bandwidth_in_kbps(const struct dc_crtc_timing * timing,uint32_t bpp_x16,uint32_t num_slices_h,bool is_dp)979 uint32_t dc_dsc_stream_bandwidth_in_kbps(const struct dc_crtc_timing *timing,
980 uint32_t bpp_x16, uint32_t num_slices_h, bool is_dp)
981 {
982 uint32_t overhead_in_kbps;
983 struct fixed31_32 bpp;
984 struct fixed31_32 actual_bandwidth_in_kbps;
985
986 overhead_in_kbps = dc_dsc_stream_bandwidth_overhead_in_kbps(
987 timing, num_slices_h, is_dp);
988 bpp = dc_fixpt_from_fraction(bpp_x16, 16);
989 actual_bandwidth_in_kbps = dc_fixpt_from_fraction(timing->pix_clk_100hz, 10);
990 actual_bandwidth_in_kbps = dc_fixpt_mul(actual_bandwidth_in_kbps, bpp);
991 actual_bandwidth_in_kbps = dc_fixpt_add_int(actual_bandwidth_in_kbps, overhead_in_kbps);
992 return dc_fixpt_ceil(actual_bandwidth_in_kbps);
993 }
994
dc_dsc_stream_bandwidth_overhead_in_kbps(const struct dc_crtc_timing * timing,const int num_slices_h,const bool is_dp)995 uint32_t dc_dsc_stream_bandwidth_overhead_in_kbps(
996 const struct dc_crtc_timing *timing,
997 const int num_slices_h,
998 const bool is_dp)
999 {
1000 struct fixed31_32 max_dsc_overhead;
1001 struct fixed31_32 refresh_rate;
1002
1003 if (dsc_policy_disable_dsc_stream_overhead || !is_dp)
1004 return 0;
1005
1006 /* use target bpp that can take entire target bandwidth */
1007 refresh_rate = dc_fixpt_from_int(timing->pix_clk_100hz);
1008 refresh_rate = dc_fixpt_div_int(refresh_rate, timing->h_total);
1009 refresh_rate = dc_fixpt_div_int(refresh_rate, timing->v_total);
1010 refresh_rate = dc_fixpt_mul_int(refresh_rate, 100);
1011
1012 max_dsc_overhead = dc_fixpt_from_int(num_slices_h);
1013 max_dsc_overhead = dc_fixpt_mul_int(max_dsc_overhead, timing->v_total);
1014 max_dsc_overhead = dc_fixpt_mul_int(max_dsc_overhead, 256);
1015 max_dsc_overhead = dc_fixpt_div_int(max_dsc_overhead, 1000);
1016 max_dsc_overhead = dc_fixpt_mul(max_dsc_overhead, refresh_rate);
1017
1018 return dc_fixpt_ceil(max_dsc_overhead);
1019 }
1020
dc_dsc_get_policy_for_timing(const struct dc_crtc_timing * timing,uint32_t max_target_bpp_limit_override_x16,struct dc_dsc_policy * policy)1021 void dc_dsc_get_policy_for_timing(const struct dc_crtc_timing *timing,
1022 uint32_t max_target_bpp_limit_override_x16,
1023 struct dc_dsc_policy *policy)
1024 {
1025 uint32_t bpc = 0;
1026
1027 policy->min_target_bpp = 0;
1028 policy->max_target_bpp = 0;
1029
1030 /* DSC Policy: Use minimum number of slices that fits the pixel clock */
1031 policy->use_min_slices_h = true;
1032
1033 /* DSC Policy: Use max available slices
1034 * (in our case 4 for or 8, depending on the mode)
1035 */
1036 policy->max_slices_h = 0;
1037
1038 /* DSC Policy: Use slice height recommended
1039 * by VESA DSC Spreadsheet user guide
1040 */
1041 policy->min_slice_height = 108;
1042
1043 /* DSC Policy: follow DP specs with an internal upper limit to 16 bpp
1044 * for better interoperability
1045 */
1046 switch (timing->display_color_depth) {
1047 case COLOR_DEPTH_888:
1048 bpc = 8;
1049 break;
1050 case COLOR_DEPTH_101010:
1051 bpc = 10;
1052 break;
1053 case COLOR_DEPTH_121212:
1054 bpc = 12;
1055 break;
1056 default:
1057 return;
1058 }
1059 switch (timing->pixel_encoding) {
1060 case PIXEL_ENCODING_RGB:
1061 case PIXEL_ENCODING_YCBCR444:
1062 case PIXEL_ENCODING_YCBCR422: /* assume no YCbCr422 native support */
1063 /* DP specs limits to 8 */
1064 policy->min_target_bpp = 8;
1065 /* DP specs limits to 3 x bpc */
1066 policy->max_target_bpp = 3 * bpc;
1067 break;
1068 case PIXEL_ENCODING_YCBCR420:
1069 /* DP specs limits to 6 */
1070 policy->min_target_bpp = 6;
1071 /* DP specs limits to 1.5 x bpc assume bpc is an even number */
1072 policy->max_target_bpp = bpc * 3 / 2;
1073 break;
1074 default:
1075 return;
1076 }
1077
1078 /* internal upper limit, default 16 bpp */
1079 if (policy->max_target_bpp > dsc_policy_max_target_bpp_limit)
1080 policy->max_target_bpp = dsc_policy_max_target_bpp_limit;
1081
1082 /* apply override */
1083 if (max_target_bpp_limit_override_x16 && policy->max_target_bpp > max_target_bpp_limit_override_x16 / 16)
1084 policy->max_target_bpp = max_target_bpp_limit_override_x16 / 16;
1085
1086 /* enable DSC when not needed, default false */
1087 if (dsc_policy_enable_dsc_when_not_needed)
1088 policy->enable_dsc_when_not_needed = dsc_policy_enable_dsc_when_not_needed;
1089 else
1090 policy->enable_dsc_when_not_needed = false;
1091 }
1092
dc_dsc_policy_set_max_target_bpp_limit(uint32_t limit)1093 void dc_dsc_policy_set_max_target_bpp_limit(uint32_t limit)
1094 {
1095 dsc_policy_max_target_bpp_limit = limit;
1096 }
1097
dc_dsc_policy_set_enable_dsc_when_not_needed(bool enable)1098 void dc_dsc_policy_set_enable_dsc_when_not_needed(bool enable)
1099 {
1100 dsc_policy_enable_dsc_when_not_needed = enable;
1101 }
1102
dc_dsc_policy_set_disable_dsc_stream_overhead(bool disable)1103 void dc_dsc_policy_set_disable_dsc_stream_overhead(bool disable)
1104 {
1105 dsc_policy_disable_dsc_stream_overhead = disable;
1106 }
1107