summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c
blob: 8cdaa6eef5d370d18d5de77c07575010bcddcdf7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
/*
 * Copyright 2019 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Author: AMD
 */

#include <drm/drm_dsc.h>
#include "dc_hw_types.h"
#include "dsc.h"
#include <drm/drm_dp_helper.h>
#include "dc.h"
#include "rc_calc.h"

/* This module's internal functions */

/* default DSC policy target bitrate limit is 16bpp */
static uint32_t dsc_policy_max_target_bpp_limit = 16;

static uint32_t dc_dsc_bandwidth_in_kbps_from_timing(
	const struct dc_crtc_timing *timing)
{
	uint32_t bits_per_channel = 0;
	uint32_t kbps;

	if (timing->flags.DSC) {
		kbps = (timing->pix_clk_100hz * timing->dsc_cfg.bits_per_pixel);
		kbps = kbps / 160 + ((kbps % 160) ? 1 : 0);
		return kbps;
	}

	switch (timing->display_color_depth) {
	case COLOR_DEPTH_666:
		bits_per_channel = 6;
		break;
	case COLOR_DEPTH_888:
		bits_per_channel = 8;
		break;
	case COLOR_DEPTH_101010:
		bits_per_channel = 10;
		break;
	case COLOR_DEPTH_121212:
		bits_per_channel = 12;
		break;
	case COLOR_DEPTH_141414:
		bits_per_channel = 14;
		break;
	case COLOR_DEPTH_161616:
		bits_per_channel = 16;
		break;
	default:
		break;
	}

	ASSERT(bits_per_channel != 0);

	kbps = timing->pix_clk_100hz / 10;
	kbps *= bits_per_channel;

	if (timing->flags.Y_ONLY != 1) {
		/*Only YOnly make reduce bandwidth by 1/3 compares to RGB*/
		kbps *= 3;
		if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR420)
			kbps /= 2;
		else if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR422)
			kbps = kbps * 2 / 3;
	}

	return kbps;

}

static bool dsc_buff_block_size_from_dpcd(int dpcd_buff_block_size, int *buff_block_size)
{

	switch (dpcd_buff_block_size) {
	case DP_DSC_RC_BUF_BLK_SIZE_1:
		*buff_block_size = 1024;
		break;
	case DP_DSC_RC_BUF_BLK_SIZE_4:
		*buff_block_size = 4 * 1024;
		break;
	case DP_DSC_RC_BUF_BLK_SIZE_16:
		*buff_block_size = 16 * 1024;
		break;
	case DP_DSC_RC_BUF_BLK_SIZE_64:
		*buff_block_size = 64 * 1024;
		break;
	default: {
			dm_error("%s: DPCD DSC buffer size not recognized.\n", __func__);
			return false;
		}
	}

	return true;
}


static bool dsc_line_buff_depth_from_dpcd(int dpcd_line_buff_bit_depth, int *line_buff_bit_depth)
{
	if (0 <= dpcd_line_buff_bit_depth && dpcd_line_buff_bit_depth <= 7)
		*line_buff_bit_depth = dpcd_line_buff_bit_depth + 9;
	else if (dpcd_line_buff_bit_depth == 8)
		*line_buff_bit_depth = 8;
	else {
		dm_error("%s: DPCD DSC buffer depth not recognized.\n", __func__);
		return false;
	}

	return true;
}


static bool dsc_throughput_from_dpcd(int dpcd_throughput, int *throughput)
{
	switch (dpcd_throughput) {
	case DP_DSC_THROUGHPUT_MODE_0_UNSUPPORTED:
		*throughput = 0;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_170:
		*throughput = 170;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_340:
		*throughput = 340;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_400:
		*throughput = 400;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_450:
		*throughput = 450;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_500:
		*throughput = 500;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_550:
		*throughput = 550;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_600:
		*throughput = 600;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_650:
		*throughput = 650;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_700:
		*throughput = 700;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_750:
		*throughput = 750;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_800:
		*throughput = 800;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_850:
		*throughput = 850;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_900:
		*throughput = 900;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_950:
		*throughput = 950;
		break;
	case DP_DSC_THROUGHPUT_MODE_0_1000:
		*throughput = 1000;
		break;
	default: {
			dm_error("%s: DPCD DSC throughput mode not recognized.\n", __func__);
			return false;
		}
	}

	return true;
}


static bool dsc_bpp_increment_div_from_dpcd(int bpp_increment_dpcd, uint32_t *bpp_increment_div)
{

	switch (bpp_increment_dpcd) {
	case 0:
		*bpp_increment_div = 16;
		break;
	case 1:
		*bpp_increment_div = 8;
		break;
	case 2:
		*bpp_increment_div = 4;
		break;
	case 3:
		*bpp_increment_div = 2;
		break;
	case 4:
		*bpp_increment_div = 1;
		break;
	default: {
		dm_error("%s: DPCD DSC bits-per-pixel increment not recognized.\n", __func__);
		return false;
	}
	}

	return true;
}

static void get_dsc_enc_caps(
	const struct display_stream_compressor *dsc,
	struct dsc_enc_caps *dsc_enc_caps,
	int pixel_clock_100Hz)
{
	// This is a static HW query, so we can use any DSC

	memset(dsc_enc_caps, 0, sizeof(struct dsc_enc_caps));
	if (dsc) {
		if (!dsc->ctx->dc->debug.disable_dsc)
			dsc->funcs->dsc_get_enc_caps(dsc_enc_caps, pixel_clock_100Hz);
		if (dsc->ctx->dc->debug.native422_support)
			dsc_enc_caps->color_formats.bits.YCBCR_NATIVE_422 = 1;
	}
}

/* Returns 'false' if no intersection was found for at least one capablity.
 * It also implicitly validates some sink caps against invalid value of zero.
 */
static bool 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)
{
	int32_t max_slices;
	int32_t total_sink_throughput;

	memset(dsc_common_caps, 0, sizeof(struct dsc_enc_caps));

	dsc_common_caps->dsc_version = min(dsc_sink_caps->dsc_version, dsc_enc_caps->dsc_version);
	if (!dsc_common_caps->dsc_version)
		return false;

	dsc_common_caps->slice_caps.bits.NUM_SLICES_1 = dsc_sink_caps->slice_caps1.bits.NUM_SLICES_1 && dsc_enc_caps->slice_caps.bits.NUM_SLICES_1;
	dsc_common_caps->slice_caps.bits.NUM_SLICES_2 = dsc_sink_caps->slice_caps1.bits.NUM_SLICES_2 && dsc_enc_caps->slice_caps.bits.NUM_SLICES_2;
	dsc_common_caps->slice_caps.bits.NUM_SLICES_4 = dsc_sink_caps->slice_caps1.bits.NUM_SLICES_4 && dsc_enc_caps->slice_caps.bits.NUM_SLICES_4;
	dsc_common_caps->slice_caps.bits.NUM_SLICES_8 = dsc_sink_caps->slice_caps1.bits.NUM_SLICES_8 && dsc_enc_caps->slice_caps.bits.NUM_SLICES_8;
	if (!dsc_common_caps->slice_caps.raw)
		return false;

	dsc_common_caps->lb_bit_depth = min(dsc_sink_caps->lb_bit_depth, dsc_enc_caps->lb_bit_depth);
	if (!dsc_common_caps->lb_bit_depth)
		return false;

	dsc_common_caps->is_block_pred_supported = dsc_sink_caps->is_block_pred_supported && dsc_enc_caps->is_block_pred_supported;

	dsc_common_caps->color_formats.raw = dsc_sink_caps->color_formats.raw & dsc_enc_caps->color_formats.raw;
	if (!dsc_common_caps->color_formats.raw)
		return false;

	dsc_common_caps->color_depth.raw = dsc_sink_caps->color_depth.raw & dsc_enc_caps->color_depth.raw;
	if (!dsc_common_caps->color_depth.raw)
		return false;

	max_slices = 0;
	if (dsc_common_caps->slice_caps.bits.NUM_SLICES_1)
		max_slices = 1;

	if (dsc_common_caps->slice_caps.bits.NUM_SLICES_2)
		max_slices = 2;

	if (dsc_common_caps->slice_caps.bits.NUM_SLICES_4)
		max_slices = 4;

	total_sink_throughput = max_slices * dsc_sink_caps->throughput_mode_0_mps;
	if (pixel_encoding == PIXEL_ENCODING_YCBCR422 || pixel_encoding == PIXEL_ENCODING_YCBCR420)
		total_sink_throughput = max_slices * dsc_sink_caps->throughput_mode_1_mps;

	dsc_common_caps->max_total_throughput_mps = min(total_sink_throughput, dsc_enc_caps->max_total_throughput_mps);

	dsc_common_caps->max_slice_width = min(dsc_sink_caps->max_slice_width, dsc_enc_caps->max_slice_width);
	if (!dsc_common_caps->max_slice_width)
		return false;

	dsc_common_caps->bpp_increment_div = min(dsc_sink_caps->bpp_increment_div, dsc_enc_caps->bpp_increment_div);

	// TODO DSC: Remove this workaround for N422 and 420 once it's fixed, or move it to get_dsc_encoder_caps()
	if (pixel_encoding == PIXEL_ENCODING_YCBCR422 || pixel_encoding == PIXEL_ENCODING_YCBCR420)
		dsc_common_caps->bpp_increment_div = min(dsc_common_caps->bpp_increment_div, (uint32_t)8);

	return true;
}

static inline uint32_t dsc_div_by_10_round_up(uint32_t value)
{
	return (value + 9) / 10;
}

/* Get DSC bandwidth range based on [min_bpp, max_bpp] target bitrate range, and timing's pixel clock
 * and uncompressed bandwidth.
 */
static void get_dsc_bandwidth_range(
		const uint32_t min_bpp,
		const uint32_t max_bpp,
		const struct dsc_enc_caps *dsc_caps,
		const struct dc_crtc_timing *timing,
		struct dc_dsc_bw_range *range)
{
	/* native stream bandwidth */
	range->stream_kbps = dc_dsc_bandwidth_in_kbps_from_timing(timing);

	/* max dsc target bpp */
	range->max_kbps = dsc_div_by_10_round_up(max_bpp * timing->pix_clk_100hz);
	range->max_target_bpp_x16 = max_bpp * 16;
	if (range->max_kbps > range->stream_kbps) {
		/* max dsc target bpp is capped to native bandwidth */
		range->max_kbps = range->stream_kbps;
		range->max_target_bpp_x16 = calc_dsc_bpp_x16(range->stream_kbps, timing->pix_clk_100hz, dsc_caps->bpp_increment_div);
	}

	/* min dsc target bpp */
	range->min_kbps = dsc_div_by_10_round_up(min_bpp * timing->pix_clk_100hz);
	range->min_target_bpp_x16 = min_bpp * 16;
	if (range->min_kbps > range->max_kbps) {
		/* min dsc target bpp is capped to max dsc bandwidth*/
		range->min_kbps = range->max_kbps;
		range->min_target_bpp_x16 = range->max_target_bpp_x16;
	}
}


/* Decides if DSC should be used and calculates target bpp if it should, applying DSC policy.
 *
 * Returns:
 *     - 'true' if DSC was required by policy and was successfully applied
 *     - 'false' if DSC was not necessary (e.g. if uncompressed stream fits 'target_bandwidth_kbps'),
 *        or if it couldn't be applied based on DSC policy.
 */
static bool 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,
		int *target_bpp_x16)
{
	bool should_use_dsc = false;
	struct dc_dsc_bw_range range;

	memset(&range, 0, sizeof(range));

	get_dsc_bandwidth_range(policy->min_target_bpp, policy->max_target_bpp,
			dsc_common_caps, timing, &range);
	if (target_bandwidth_kbps >= range.stream_kbps) {
		/* enough bandwidth without dsc */
		*target_bpp_x16 = 0;
		should_use_dsc = false;
	} else if (target_bandwidth_kbps >= range.max_kbps) {
		/* use max target bpp allowed */
		*target_bpp_x16 = range.max_target_bpp_x16;
		should_use_dsc = true;
	} else if (target_bandwidth_kbps >= range.min_kbps) {
		/* use target bpp that can take entire target bandwidth */
		*target_bpp_x16 = calc_dsc_bpp_x16(target_bandwidth_kbps, timing->pix_clk_100hz, dsc_common_caps->bpp_increment_div);
		should_use_dsc = true;
	} else {
		/* not enough bandwidth to fulfill minimum requirement */
		*target_bpp_x16 = 0;
		should_use_dsc = false;
	}

	return should_use_dsc;
}

#define MIN_AVAILABLE_SLICES_SIZE  4

static int get_available_dsc_slices(union dsc_enc_slice_caps slice_caps, int *available_slices)
{
	int idx = 0;

	memset(available_slices, -1, MIN_AVAILABLE_SLICES_SIZE);

	if (slice_caps.bits.NUM_SLICES_1)
		available_slices[idx++] = 1;

	if (slice_caps.bits.NUM_SLICES_2)
		available_slices[idx++] = 2;

	if (slice_caps.bits.NUM_SLICES_4)
		available_slices[idx++] = 4;

	if (slice_caps.bits.NUM_SLICES_8)
		available_slices[idx++] = 8;

	return idx;
}


static int get_max_dsc_slices(union dsc_enc_slice_caps slice_caps)
{
	int max_slices = 0;
	int available_slices[MIN_AVAILABLE_SLICES_SIZE];
	int end_idx = get_available_dsc_slices(slice_caps, &available_slices[0]);

	if (end_idx > 0)
		max_slices = available_slices[end_idx - 1];

	return max_slices;
}


// Increment sice number in available sice numbers stops if possible, or just increment if not
static int inc_num_slices(union dsc_enc_slice_caps slice_caps, int num_slices)
{
	// Get next bigger num slices available in common caps
	int available_slices[MIN_AVAILABLE_SLICES_SIZE];
	int end_idx;
	int i;
	int new_num_slices = num_slices;

	end_idx = get_available_dsc_slices(slice_caps, &available_slices[0]);
	if (end_idx == 0) {
		// No available slices found
		new_num_slices++;
		return new_num_slices;
	}

	// Numbers of slices found - get the next bigger number
	for (i = 0; i < end_idx; i++) {
		if (new_num_slices < available_slices[i]) {
			new_num_slices = available_slices[i];
			break;
		}
	}

	if (new_num_slices == num_slices) // No biger number of slices found
		new_num_slices++;

	return new_num_slices;
}


// Decrement sice number in available sice numbers stops if possible, or just decrement if not. Stop at zero.
static int dec_num_slices(union dsc_enc_slice_caps slice_caps, int num_slices)
{
	// Get next bigger num slices available in common caps
	int available_slices[MIN_AVAILABLE_SLICES_SIZE];
	int end_idx;
	int i;
	int new_num_slices = num_slices;

	end_idx = get_available_dsc_slices(slice_caps, &available_slices[0]);
	if (end_idx == 0 && new_num_slices > 0) {
		// No numbers of slices found
		new_num_slices++;
		return new_num_slices;
	}

	// Numbers of slices found - get the next smaller number
	for (i = end_idx - 1; i >= 0; i--) {
		if (new_num_slices > available_slices[i]) {
			new_num_slices = available_slices[i];
			break;
		}
	}

	if (new_num_slices == num_slices) {
		// No smaller number of slices found
		new_num_slices--;
		if (new_num_slices < 0)
			new_num_slices = 0;
	}

	return new_num_slices;
}


// Choose next bigger number of slices if the requested number of slices is not available
static int fit_num_slices_up(union dsc_enc_slice_caps slice_caps, int num_slices)
{
	// Get next bigger num slices available in common caps
	int available_slices[MIN_AVAILABLE_SLICES_SIZE];
	int end_idx;
	int i;
	int new_num_slices = num_slices;

	end_idx = get_available_dsc_slices(slice_caps, &available_slices[0]);
	if (end_idx == 0) {
		// No available slices found
		new_num_slices++;
		return new_num_slices;
	}

	// Numbers of slices found - get the equal or next bigger number
	for (i = 0; i < end_idx; i++) {
		if (new_num_slices <= available_slices[i]) {
			new_num_slices = available_slices[i];
			break;
		}
	}

	return new_num_slices;
}


/* Attempts to set DSC configuration for the stream, applying DSC policy.
 * Returns 'true' if successful or 'false' if not.
 *
 * Parameters:
 *
 * dsc_sink_caps       - DSC sink decoder capabilities (from DPCD)
 *
 * dsc_enc_caps        - DSC encoder capabilities
 *
 * target_bandwidth_kbps  - Target bandwidth to fit the stream into.
 *                          If 0, do not calculate target bpp.
 *
 * timing              - The stream timing to fit into 'target_bandwidth_kbps' or apply
 *                       maximum compression to, if 'target_badwidth == 0'
 *
 * dsc_cfg             - DSC configuration to use if it was possible to come up with
 *                       one for the given inputs.
 *                       The target bitrate after DSC can be calculated by multiplying
 *                       dsc_cfg.bits_per_pixel (in U6.4 format) by pixel rate, e.g.
 *
 *                       dsc_stream_bitrate_kbps = (int)ceil(timing->pix_clk_khz * dsc_cfg.bits_per_pixel / 16.0);
 */
static bool 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,
		struct dc_dsc_config *dsc_cfg)
{
	struct dsc_enc_caps dsc_common_caps;
	int max_slices_h;
	int min_slices_h;
	int num_slices_h;
	int pic_width;
	int slice_width;
	int target_bpp;
	int sink_per_slice_throughput_mps;
	int branch_max_throughput_mps = 0;
	bool is_dsc_possible = false;
	int pic_height;
	int slice_height;
	struct dc_dsc_policy policy;

	memset(dsc_cfg, 0, sizeof(struct dc_dsc_config));

	dc_dsc_get_policy_for_timing(timing, &policy);
	pic_width = timing->h_addressable + timing->h_border_left + timing->h_border_right;
	pic_height = timing->v_addressable + timing->v_border_top + timing->v_border_bottom;

	if (!dsc_sink_caps->is_dsc_supported)
		goto done;

	if (dsc_sink_caps->branch_max_line_width && dsc_sink_caps->branch_max_line_width < pic_width)
		goto done;

	// Intersect decoder with encoder DSC caps and validate DSC settings
	is_dsc_possible = intersect_dsc_caps(dsc_sink_caps, dsc_enc_caps, timing->pixel_encoding, &dsc_common_caps);
	if (!is_dsc_possible)
		goto done;

	if (target_bandwidth_kbps > 0) {
		is_dsc_possible = decide_dsc_target_bpp_x16(
				&policy,
				&dsc_common_caps,
				target_bandwidth_kbps,
				timing,
				&target_bpp);
		dsc_cfg->bits_per_pixel = target_bpp;
	}
	if (!is_dsc_possible)
		goto done;

	sink_per_slice_throughput_mps = 0;

	// Validate available DSC settings against the mode timing

	// Validate color format (and pick up the throughput values)
	dsc_cfg->ycbcr422_simple = false;
	switch (timing->pixel_encoding)	{
	case PIXEL_ENCODING_RGB:
		is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.RGB;
		sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_0_mps;
		branch_max_throughput_mps = dsc_sink_caps->branch_overall_throughput_0_mps;
		break;
	case PIXEL_ENCODING_YCBCR444:
		is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.YCBCR_444;
		sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_0_mps;
		branch_max_throughput_mps = dsc_sink_caps->branch_overall_throughput_0_mps;
		break;
	case PIXEL_ENCODING_YCBCR422:
		is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.YCBCR_NATIVE_422;
		sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_1_mps;
		branch_max_throughput_mps = dsc_sink_caps->branch_overall_throughput_1_mps;
		if (!is_dsc_possible) {
			is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.YCBCR_SIMPLE_422;
			dsc_cfg->ycbcr422_simple = is_dsc_possible;
			sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_0_mps;
		}
		break;
	case PIXEL_ENCODING_YCBCR420:
		is_dsc_possible = (bool)dsc_common_caps.color_formats.bits.YCBCR_NATIVE_420;
		sink_per_slice_throughput_mps = dsc_sink_caps->throughput_mode_1_mps;
		branch_max_throughput_mps = dsc_sink_caps->branch_overall_throughput_1_mps;
		break;
	default:
		is_dsc_possible = false;
	}

	// Validate branch's maximum throughput
	if (branch_max_throughput_mps && dsc_div_by_10_round_up(timing->pix_clk_100hz) > branch_max_throughput_mps * 1000)
		is_dsc_possible = false;

	if (!is_dsc_possible)
		goto done;

	// Color depth
	switch (timing->display_color_depth) {
	case COLOR_DEPTH_888:
		is_dsc_possible = (bool)dsc_common_caps.color_depth.bits.COLOR_DEPTH_8_BPC;
		break;
	case COLOR_DEPTH_101010:
		is_dsc_possible = (bool)dsc_common_caps.color_depth.bits.COLOR_DEPTH_10_BPC;
		break;
	case COLOR_DEPTH_121212:
		is_dsc_possible = (bool)dsc_common_caps.color_depth.bits.COLOR_DEPTH_12_BPC;
		break;
	default:
		is_dsc_possible = false;
	}

	if (!is_dsc_possible)
		goto done;

	// Slice width (i.e. number of slices per line)
	max_slices_h = get_max_dsc_slices(dsc_common_caps.slice_caps);

	while (max_slices_h > 0) {
		if (pic_width % max_slices_h == 0)
			break;

		max_slices_h = dec_num_slices(dsc_common_caps.slice_caps, max_slices_h);
	}

	is_dsc_possible = (dsc_common_caps.max_slice_width > 0);
	if (!is_dsc_possible)
		goto done;

	min_slices_h = pic_width / dsc_common_caps.max_slice_width;
	if (pic_width % dsc_common_caps.max_slice_width)
		min_slices_h++;

	min_slices_h = fit_num_slices_up(dsc_common_caps.slice_caps, min_slices_h);

	while (min_slices_h <= max_slices_h) {
		int pix_clk_per_slice_khz = dsc_div_by_10_round_up(timing->pix_clk_100hz) / min_slices_h;
		if (pix_clk_per_slice_khz <= sink_per_slice_throughput_mps * 1000)
			break;

		min_slices_h = inc_num_slices(dsc_common_caps.slice_caps, min_slices_h);
	}

	if (pic_width % min_slices_h != 0)
		min_slices_h = 0; // DSC TODO: Maybe try increasing the number of slices first?

	is_dsc_possible = (min_slices_h <= max_slices_h);
	if (!is_dsc_possible)
		goto done;

	if (policy.use_min_slices_h) {
		if (min_slices_h > 0)
			num_slices_h = min_slices_h;
		else if (max_slices_h > 0) { // Fall back to max slices if min slices is not working out
			if (policy.max_slices_h)
				num_slices_h = min(policy.max_slices_h, max_slices_h);
			else
				num_slices_h = max_slices_h;
		} else
			is_dsc_possible = false;
	} else {
		if (max_slices_h > 0) {
			if (policy.max_slices_h)
				num_slices_h = min(policy.max_slices_h, max_slices_h);
			else
				num_slices_h = max_slices_h;
		} else if (min_slices_h > 0) // Fall back to min slices if max slices is not possible
			num_slices_h = min_slices_h;
		else
			is_dsc_possible = false;
	}

	if (!is_dsc_possible)
		goto done;

	dsc_cfg->num_slices_h = num_slices_h;
	slice_width = pic_width / num_slices_h;

	is_dsc_possible = slice_width <= dsc_common_caps.max_slice_width;
	if (!is_dsc_possible)
		goto done;

	// Slice height (i.e. number of slices per column): start with policy and pick the first one that height is divisible by.
	// For 4:2:0 make sure the slice height is divisible by 2 as well.
	if (min_slice_height_override == 0)
		slice_height = min(policy.min_slice_height, pic_height);
	else
		slice_height = min(min_slice_height_override, pic_height);

	while (slice_height < pic_height && (pic_height % slice_height != 0 ||
		(timing->pixel_encoding == PIXEL_ENCODING_YCBCR420 && slice_height % 2 != 0)))
		slice_height++;

	if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR420) // For the case when pic_height < dsc_policy.min_sice_height
		is_dsc_possible = (slice_height % 2 == 0);

	if (!is_dsc_possible)
		goto done;

	dsc_cfg->num_slices_v = pic_height/slice_height;

	// Final decission: can we do DSC or not?
	if (is_dsc_possible) {
		// Fill out the rest of DSC settings
		dsc_cfg->block_pred_enable = dsc_common_caps.is_block_pred_supported;
		dsc_cfg->linebuf_depth = dsc_common_caps.lb_bit_depth;
		dsc_cfg->version_minor = (dsc_common_caps.dsc_version & 0xf0) >> 4;
	}

done:
	if (!is_dsc_possible)
		memset(dsc_cfg, 0, sizeof(struct dc_dsc_config));

	return is_dsc_possible;
}

bool 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)
{
	if (!dpcd_dsc_basic_data)
		return false;

	dsc_sink_caps->is_dsc_supported = (dpcd_dsc_basic_data[DP_DSC_SUPPORT - DP_DSC_SUPPORT] & DP_DSC_DECOMPRESSION_IS_SUPPORTED) != 0;
	if (!dsc_sink_caps->is_dsc_supported)
		return false;

	dsc_sink_caps->dsc_version = dpcd_dsc_basic_data[DP_DSC_REV - DP_DSC_SUPPORT];

	{
		int buff_block_size;
		int buff_size;

		if (!dsc_buff_block_size_from_dpcd(dpcd_dsc_basic_data[DP_DSC_RC_BUF_BLK_SIZE - DP_DSC_SUPPORT], &buff_block_size))
			return false;

		buff_size = dpcd_dsc_basic_data[DP_DSC_RC_BUF_SIZE - DP_DSC_SUPPORT] + 1;
		dsc_sink_caps->rc_buffer_size = buff_size * buff_block_size;
	}

	dsc_sink_caps->slice_caps1.raw = dpcd_dsc_basic_data[DP_DSC_SLICE_CAP_1 - DP_DSC_SUPPORT];
	if (!dsc_line_buff_depth_from_dpcd(dpcd_dsc_basic_data[DP_DSC_LINE_BUF_BIT_DEPTH - DP_DSC_SUPPORT], &dsc_sink_caps->lb_bit_depth))
		return false;

	dsc_sink_caps->is_block_pred_supported =
		(dpcd_dsc_basic_data[DP_DSC_BLK_PREDICTION_SUPPORT - DP_DSC_SUPPORT] & DP_DSC_BLK_PREDICTION_IS_SUPPORTED) != 0;

	dsc_sink_caps->edp_max_bits_per_pixel =
		dpcd_dsc_basic_data[DP_DSC_MAX_BITS_PER_PIXEL_LOW - DP_DSC_SUPPORT] |
		dpcd_dsc_basic_data[DP_DSC_MAX_BITS_PER_PIXEL_HI - DP_DSC_SUPPORT] << 8;

	dsc_sink_caps->color_formats.raw = dpcd_dsc_basic_data[DP_DSC_DEC_COLOR_FORMAT_CAP - DP_DSC_SUPPORT];
	dsc_sink_caps->color_depth.raw = dpcd_dsc_basic_data[DP_DSC_DEC_COLOR_DEPTH_CAP - DP_DSC_SUPPORT];

	{
		int dpcd_throughput = dpcd_dsc_basic_data[DP_DSC_PEAK_THROUGHPUT - DP_DSC_SUPPORT];

		if (!dsc_throughput_from_dpcd(dpcd_throughput & DP_DSC_THROUGHPUT_MODE_0_MASK, &dsc_sink_caps->throughput_mode_0_mps))
			return false;

		dpcd_throughput = (dpcd_throughput & DP_DSC_THROUGHPUT_MODE_1_MASK) >> DP_DSC_THROUGHPUT_MODE_1_SHIFT;
		if (!dsc_throughput_from_dpcd(dpcd_throughput, &dsc_sink_caps->throughput_mode_1_mps))
			return false;
	}

	dsc_sink_caps->max_slice_width = dpcd_dsc_basic_data[DP_DSC_MAX_SLICE_WIDTH - DP_DSC_SUPPORT] * 320;
	dsc_sink_caps->slice_caps2.raw = dpcd_dsc_basic_data[DP_DSC_SLICE_CAP_2 - DP_DSC_SUPPORT];

	if (!dsc_bpp_increment_div_from_dpcd(dpcd_dsc_basic_data[DP_DSC_BITS_PER_PIXEL_INC - DP_DSC_SUPPORT], &dsc_sink_caps->bpp_increment_div))
		return false;

	if (dc->debug.dsc_bpp_increment_div) {
		/* dsc_bpp_increment_div should onl be 1, 2, 4, 8 or 16, but rather than rejecting invalid values,
		 * we'll accept all and get it into range. This also makes the above check against 0 redundant,
		 * but that one stresses out the override will be only used if it's not 0.
		 */
		if (dc->debug.dsc_bpp_increment_div >= 1)
			dsc_sink_caps->bpp_increment_div = 1;
		if (dc->debug.dsc_bpp_increment_div >= 2)
			dsc_sink_caps->bpp_increment_div = 2;
		if (dc->debug.dsc_bpp_increment_div >= 4)
			dsc_sink_caps->bpp_increment_div = 4;
		if (dc->debug.dsc_bpp_increment_div >= 8)
			dsc_sink_caps->bpp_increment_div = 8;
		if (dc->debug.dsc_bpp_increment_div >= 16)
			dsc_sink_caps->bpp_increment_div = 16;
	}

	/* Extended caps */
	if (dpcd_dsc_branch_decoder_caps == NULL) { // branch decoder DPCD DSC data can be null for non branch device
		dsc_sink_caps->branch_overall_throughput_0_mps = 0;
		dsc_sink_caps->branch_overall_throughput_1_mps = 0;
		dsc_sink_caps->branch_max_line_width = 0;
		return true;
	}

	dsc_sink_caps->branch_overall_throughput_0_mps = dpcd_dsc_branch_decoder_caps[DP_DSC_BRANCH_OVERALL_THROUGHPUT_0 - DP_DSC_BRANCH_OVERALL_THROUGHPUT_0];
	if (dsc_sink_caps->branch_overall_throughput_0_mps == 0)
		dsc_sink_caps->branch_overall_throughput_0_mps = 0;
	else if (dsc_sink_caps->branch_overall_throughput_0_mps == 1)
		dsc_sink_caps->branch_overall_throughput_0_mps = 680;
	else {
		dsc_sink_caps->branch_overall_throughput_0_mps *= 50;
		dsc_sink_caps->branch_overall_throughput_0_mps += 600;
	}

	dsc_sink_caps->branch_overall_throughput_1_mps = dpcd_dsc_branch_decoder_caps[DP_DSC_BRANCH_OVERALL_THROUGHPUT_1 - DP_DSC_BRANCH_OVERALL_THROUGHPUT_0];
	if (dsc_sink_caps->branch_overall_throughput_1_mps == 0)
		dsc_sink_caps->branch_overall_throughput_1_mps = 0;
	else if (dsc_sink_caps->branch_overall_throughput_1_mps == 1)
		dsc_sink_caps->branch_overall_throughput_1_mps = 680;
	else {
		dsc_sink_caps->branch_overall_throughput_1_mps *= 50;
		dsc_sink_caps->branch_overall_throughput_1_mps += 600;
	}

	dsc_sink_caps->branch_max_line_width = dpcd_dsc_branch_decoder_caps[DP_DSC_BRANCH_MAX_LINE_WIDTH - DP_DSC_BRANCH_OVERALL_THROUGHPUT_0] * 320;
	ASSERT(dsc_sink_caps->branch_max_line_width == 0 || dsc_sink_caps->branch_max_line_width >= 5120);

	return true;
}


/* If DSC is possbile, get DSC bandwidth range based on [min_bpp, max_bpp] target bitrate range and
 * timing's pixel clock and uncompressed bandwidth.
 * If DSC is not possible, leave '*range' untouched.
 */
bool dc_dsc_compute_bandwidth_range(
		const struct display_stream_compressor *dsc,
		const uint32_t dsc_min_slice_height_override,
		const uint32_t min_bpp,
		const uint32_t max_bpp,
		const struct dsc_dec_dpcd_caps *dsc_sink_caps,
		const struct dc_crtc_timing *timing,
		struct dc_dsc_bw_range *range)
{
	bool is_dsc_possible = false;
	struct dsc_enc_caps dsc_enc_caps;
	struct dsc_enc_caps dsc_common_caps;
	struct dc_dsc_config config;

	get_dsc_enc_caps(dsc, &dsc_enc_caps, timing->pix_clk_100hz);

	is_dsc_possible = intersect_dsc_caps(dsc_sink_caps, &dsc_enc_caps,
			timing->pixel_encoding, &dsc_common_caps);

	if (is_dsc_possible)
		is_dsc_possible = setup_dsc_config(dsc_sink_caps, &dsc_enc_caps, 0, timing,
				dsc_min_slice_height_override, &config);

	if (is_dsc_possible)
		get_dsc_bandwidth_range(min_bpp, max_bpp, &dsc_common_caps, timing, range);

	return is_dsc_possible;
}

bool dc_dsc_compute_config(
		const struct display_stream_compressor *dsc,
		const struct dsc_dec_dpcd_caps *dsc_sink_caps,
		const uint32_t dsc_min_slice_height_override,
		uint32_t target_bandwidth_kbps,
		const struct dc_crtc_timing *timing,
		struct dc_dsc_config *dsc_cfg)
{
	bool is_dsc_possible = false;
	struct dsc_enc_caps dsc_enc_caps;

	get_dsc_enc_caps(dsc, &dsc_enc_caps, timing->pix_clk_100hz);
	is_dsc_possible = setup_dsc_config(dsc_sink_caps,
			&dsc_enc_caps,
			target_bandwidth_kbps,
			timing, dsc_min_slice_height_override, dsc_cfg);
	return is_dsc_possible;
}

void dc_dsc_get_policy_for_timing(const struct dc_crtc_timing *timing, struct dc_dsc_policy *policy)
{
	uint32_t bpc = 0;

	policy->min_target_bpp = 0;
	policy->max_target_bpp = 0;

	/* DSC Policy: Use minimum number of slices that fits the pixel clock */
	policy->use_min_slices_h = true;

	/* DSC Policy: Use max available slices
	 * (in our case 4 for or 8, depending on the mode)
	 */
	policy->max_slices_h = 0;

	/* DSC Policy: Use slice height recommended
	 * by VESA DSC Spreadsheet user guide
	 */
	policy->min_slice_height = 108;

	/* DSC Policy: follow DP specs with an internal upper limit to 16 bpp
	 * for better interoperability
	 */
	switch (timing->display_color_depth) {
	case COLOR_DEPTH_888:
		bpc = 8;
		break;
	case COLOR_DEPTH_101010:
		bpc = 10;
		break;
	case COLOR_DEPTH_121212:
		bpc = 12;
		break;
	default:
		return;
	}
	switch (timing->pixel_encoding) {
	case PIXEL_ENCODING_RGB:
	case PIXEL_ENCODING_YCBCR444:
	case PIXEL_ENCODING_YCBCR422: /* assume no YCbCr422 native support */
		/* DP specs limits to 8 */
		policy->min_target_bpp = 8;
		/* DP specs limits to 3 x bpc */
		policy->max_target_bpp = 3 * bpc;
		break;
	case PIXEL_ENCODING_YCBCR420:
		/* DP specs limits to 6 */
		policy->min_target_bpp = 6;
		/* DP specs limits to 1.5 x bpc assume bpc is an even number */
		policy->max_target_bpp = bpc * 3 / 2;
		break;
	default:
		return;
	}
	/* internal upper limit, default 16 bpp */
	if (policy->max_target_bpp > dsc_policy_max_target_bpp_limit)
		policy->max_target_bpp = dsc_policy_max_target_bpp_limit;
}

void dc_dsc_policy_set_max_target_bpp_limit(uint32_t limit)
{
	dsc_policy_max_target_bpp_limit = limit;
}