xref: /openbmc/linux/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.c (revision d699090510c3223641a23834b4710e2d4309a6ad)
1 /*
2  * Copyright 2022 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  * Authors: AMD
23  *
24  */
25 
26 /* FILE POLICY AND INTENDED USAGE:
27  * This file implements all generic dp link training helper functions and top
28  * level generic training sequence. All variations of dp link training sequence
29  * should be called inside the top level training functions in this file to
30  * ensure the integrity of our overall training procedure across different types
31  * of link encoding and back end hardware.
32  */
33 #include "link_dp_training.h"
34 #include "link_dp_training_8b_10b.h"
35 #include "link_dp_training_128b_132b.h"
36 #include "link_dp_training_auxless.h"
37 #include "link_dp_training_dpia.h"
38 #include "link_dp_training_fixed_vs_pe_retimer.h"
39 #include "link_dpcd.h"
40 #include "link/accessories/link_dp_trace.h"
41 #include "link_dp_phy.h"
42 #include "link_dp_capability.h"
43 #include "link_edp_panel_control.h"
44 #include "link/link_detection.h"
45 #include "link/link_validation.h"
46 #include "atomfirmware.h"
47 #include "link_enc_cfg.h"
48 #include "resource.h"
49 #include "dm_helpers.h"
50 
51 #define DC_LOGGER \
52 	link->ctx->logger
53 
54 #define POST_LT_ADJ_REQ_LIMIT 6
55 #define POST_LT_ADJ_REQ_TIMEOUT 200
56 #define LINK_TRAINING_RETRY_DELAY 50 /* ms */
57 
dp_log_training_result(struct dc_link * link,const struct link_training_settings * lt_settings,enum link_training_result status)58 void dp_log_training_result(
59 	struct dc_link *link,
60 	const struct link_training_settings *lt_settings,
61 	enum link_training_result status)
62 {
63 	char *link_rate = "Unknown";
64 	char *lt_result = "Unknown";
65 	char *lt_spread = "Disabled";
66 
67 	switch (lt_settings->link_settings.link_rate) {
68 	case LINK_RATE_LOW:
69 		link_rate = "RBR";
70 		break;
71 	case LINK_RATE_RATE_2:
72 		link_rate = "R2";
73 		break;
74 	case LINK_RATE_RATE_3:
75 		link_rate = "R3";
76 		break;
77 	case LINK_RATE_HIGH:
78 		link_rate = "HBR";
79 		break;
80 	case LINK_RATE_RBR2:
81 		link_rate = "RBR2";
82 		break;
83 	case LINK_RATE_RATE_6:
84 		link_rate = "R6";
85 		break;
86 	case LINK_RATE_HIGH2:
87 		link_rate = "HBR2";
88 		break;
89 	case LINK_RATE_RATE_8:
90 		link_rate = "R8";
91 		break;
92 	case LINK_RATE_HIGH3:
93 		link_rate = "HBR3";
94 		break;
95 	case LINK_RATE_UHBR10:
96 		link_rate = "UHBR10";
97 		break;
98 	case LINK_RATE_UHBR13_5:
99 		link_rate = "UHBR13.5";
100 		break;
101 	case LINK_RATE_UHBR20:
102 		link_rate = "UHBR20";
103 		break;
104 	default:
105 		break;
106 	}
107 
108 	switch (status) {
109 	case LINK_TRAINING_SUCCESS:
110 		lt_result = "pass";
111 		break;
112 	case LINK_TRAINING_CR_FAIL_LANE0:
113 		lt_result = "CR failed lane0";
114 		break;
115 	case LINK_TRAINING_CR_FAIL_LANE1:
116 		lt_result = "CR failed lane1";
117 		break;
118 	case LINK_TRAINING_CR_FAIL_LANE23:
119 		lt_result = "CR failed lane23";
120 		break;
121 	case LINK_TRAINING_EQ_FAIL_CR:
122 		lt_result = "CR failed in EQ";
123 		break;
124 	case LINK_TRAINING_EQ_FAIL_CR_PARTIAL:
125 		lt_result = "CR failed in EQ partially";
126 		break;
127 	case LINK_TRAINING_EQ_FAIL_EQ:
128 		lt_result = "EQ failed";
129 		break;
130 	case LINK_TRAINING_LQA_FAIL:
131 		lt_result = "LQA failed";
132 		break;
133 	case LINK_TRAINING_LINK_LOSS:
134 		lt_result = "Link loss";
135 		break;
136 	case DP_128b_132b_LT_FAILED:
137 		lt_result = "LT_FAILED received";
138 		break;
139 	case DP_128b_132b_MAX_LOOP_COUNT_REACHED:
140 		lt_result = "max loop count reached";
141 		break;
142 	case DP_128b_132b_CHANNEL_EQ_DONE_TIMEOUT:
143 		lt_result = "channel EQ timeout";
144 		break;
145 	case DP_128b_132b_CDS_DONE_TIMEOUT:
146 		lt_result = "CDS timeout";
147 		break;
148 	default:
149 		break;
150 	}
151 
152 	switch (lt_settings->link_settings.link_spread) {
153 	case LINK_SPREAD_DISABLED:
154 		lt_spread = "Disabled";
155 		break;
156 	case LINK_SPREAD_05_DOWNSPREAD_30KHZ:
157 		lt_spread = "0.5% 30KHz";
158 		break;
159 	case LINK_SPREAD_05_DOWNSPREAD_33KHZ:
160 		lt_spread = "0.5% 33KHz";
161 		break;
162 	default:
163 		break;
164 	}
165 
166 	/* Connectivity log: link training */
167 
168 	/* TODO - DP2.0 Log: add connectivity log for FFE PRESET */
169 
170 	CONN_MSG_LT(link, "%sx%d %s VS=%d, PE=%d, DS=%s",
171 				link_rate,
172 				lt_settings->link_settings.lane_count,
173 				lt_result,
174 				lt_settings->hw_lane_settings[0].VOLTAGE_SWING,
175 				lt_settings->hw_lane_settings[0].PRE_EMPHASIS,
176 				lt_spread);
177 }
178 
dp_initialize_scrambling_data_symbols(struct dc_link * link,enum dc_dp_training_pattern pattern)179 uint8_t dp_initialize_scrambling_data_symbols(
180 	struct dc_link *link,
181 	enum dc_dp_training_pattern pattern)
182 {
183 	uint8_t disable_scrabled_data_symbols = 0;
184 
185 	switch (pattern) {
186 	case DP_TRAINING_PATTERN_SEQUENCE_1:
187 	case DP_TRAINING_PATTERN_SEQUENCE_2:
188 	case DP_TRAINING_PATTERN_SEQUENCE_3:
189 		disable_scrabled_data_symbols = 1;
190 		break;
191 	case DP_TRAINING_PATTERN_SEQUENCE_4:
192 	case DP_128b_132b_TPS1:
193 	case DP_128b_132b_TPS2:
194 		disable_scrabled_data_symbols = 0;
195 		break;
196 	default:
197 		ASSERT(0);
198 		DC_LOG_HW_LINK_TRAINING("%s: Invalid HW Training pattern: %d\n",
199 			__func__, pattern);
200 		break;
201 	}
202 	return disable_scrabled_data_symbols;
203 }
204 
205 enum dpcd_training_patterns
dp_training_pattern_to_dpcd_training_pattern(struct dc_link * link,enum dc_dp_training_pattern pattern)206 	dp_training_pattern_to_dpcd_training_pattern(
207 	struct dc_link *link,
208 	enum dc_dp_training_pattern pattern)
209 {
210 	enum dpcd_training_patterns dpcd_tr_pattern =
211 	DPCD_TRAINING_PATTERN_VIDEOIDLE;
212 
213 	switch (pattern) {
214 	case DP_TRAINING_PATTERN_SEQUENCE_1:
215 		DC_LOG_HW_LINK_TRAINING("%s: Using DP training pattern TPS1\n", __func__);
216 		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_1;
217 		break;
218 	case DP_TRAINING_PATTERN_SEQUENCE_2:
219 		DC_LOG_HW_LINK_TRAINING("%s: Using DP training pattern TPS2\n", __func__);
220 		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_2;
221 		break;
222 	case DP_TRAINING_PATTERN_SEQUENCE_3:
223 		DC_LOG_HW_LINK_TRAINING("%s: Using DP training pattern TPS3\n", __func__);
224 		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_3;
225 		break;
226 	case DP_TRAINING_PATTERN_SEQUENCE_4:
227 		DC_LOG_HW_LINK_TRAINING("%s: Using DP training pattern TPS4\n", __func__);
228 		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_4;
229 		break;
230 	case DP_128b_132b_TPS1:
231 		DC_LOG_HW_LINK_TRAINING("%s: Using DP 128b/132b training pattern TPS1\n", __func__);
232 		dpcd_tr_pattern = DPCD_128b_132b_TPS1;
233 		break;
234 	case DP_128b_132b_TPS2:
235 		DC_LOG_HW_LINK_TRAINING("%s: Using DP 128b/132b training pattern TPS2\n", __func__);
236 		dpcd_tr_pattern = DPCD_128b_132b_TPS2;
237 		break;
238 	case DP_128b_132b_TPS2_CDS:
239 		DC_LOG_HW_LINK_TRAINING("%s: Using DP 128b/132b training pattern TPS2 CDS\n",
240 					__func__);
241 		dpcd_tr_pattern = DPCD_128b_132b_TPS2_CDS;
242 		break;
243 	case DP_TRAINING_PATTERN_VIDEOIDLE:
244 		DC_LOG_HW_LINK_TRAINING("%s: Using DP training pattern videoidle\n", __func__);
245 		dpcd_tr_pattern = DPCD_TRAINING_PATTERN_VIDEOIDLE;
246 		break;
247 	default:
248 		ASSERT(0);
249 		DC_LOG_HW_LINK_TRAINING("%s: Invalid HW Training pattern: %d\n",
250 			__func__, pattern);
251 		break;
252 	}
253 
254 	return dpcd_tr_pattern;
255 }
256 
dp_get_nibble_at_index(const uint8_t * buf,uint32_t index)257 uint8_t dp_get_nibble_at_index(const uint8_t *buf,
258 	uint32_t index)
259 {
260 	uint8_t nibble;
261 	nibble = buf[index / 2];
262 
263 	if (index % 2)
264 		nibble >>= 4;
265 	else
266 		nibble &= 0x0F;
267 
268 	return nibble;
269 }
270 
dp_wait_for_training_aux_rd_interval(struct dc_link * link,uint32_t wait_in_micro_secs)271 void dp_wait_for_training_aux_rd_interval(
272 	struct dc_link *link,
273 	uint32_t wait_in_micro_secs)
274 {
275 	fsleep(wait_in_micro_secs);
276 
277 	DC_LOG_HW_LINK_TRAINING("%s:\n wait = %d\n",
278 		__func__,
279 		wait_in_micro_secs);
280 }
281 
282 /* maximum pre emphasis level allowed for each voltage swing level*/
283 static const enum dc_pre_emphasis voltage_swing_to_pre_emphasis[] = {
284 		PRE_EMPHASIS_LEVEL3,
285 		PRE_EMPHASIS_LEVEL2,
286 		PRE_EMPHASIS_LEVEL1,
287 		PRE_EMPHASIS_DISABLED };
288 
get_max_pre_emphasis_for_voltage_swing(enum dc_voltage_swing voltage)289 static enum dc_pre_emphasis get_max_pre_emphasis_for_voltage_swing(
290 	enum dc_voltage_swing voltage)
291 {
292 	enum dc_pre_emphasis pre_emphasis;
293 	pre_emphasis = PRE_EMPHASIS_MAX_LEVEL;
294 
295 	if (voltage <= VOLTAGE_SWING_MAX_LEVEL)
296 		pre_emphasis = voltage_swing_to_pre_emphasis[voltage];
297 
298 	return pre_emphasis;
299 
300 }
301 
maximize_lane_settings(const struct link_training_settings * lt_settings,struct dc_lane_settings lane_settings[LANE_COUNT_DP_MAX])302 static void maximize_lane_settings(const struct link_training_settings *lt_settings,
303 		struct dc_lane_settings lane_settings[LANE_COUNT_DP_MAX])
304 {
305 	uint32_t lane;
306 	struct dc_lane_settings max_requested;
307 
308 	max_requested.VOLTAGE_SWING = lane_settings[0].VOLTAGE_SWING;
309 	max_requested.PRE_EMPHASIS = lane_settings[0].PRE_EMPHASIS;
310 	max_requested.FFE_PRESET = lane_settings[0].FFE_PRESET;
311 
312 	/* Determine what the maximum of the requested settings are*/
313 	for (lane = 1; lane < lt_settings->link_settings.lane_count; lane++) {
314 		if (lane_settings[lane].VOLTAGE_SWING > max_requested.VOLTAGE_SWING)
315 			max_requested.VOLTAGE_SWING = lane_settings[lane].VOLTAGE_SWING;
316 
317 		if (lane_settings[lane].PRE_EMPHASIS > max_requested.PRE_EMPHASIS)
318 			max_requested.PRE_EMPHASIS = lane_settings[lane].PRE_EMPHASIS;
319 		if (lane_settings[lane].FFE_PRESET.settings.level >
320 				max_requested.FFE_PRESET.settings.level)
321 			max_requested.FFE_PRESET.settings.level =
322 					lane_settings[lane].FFE_PRESET.settings.level;
323 	}
324 
325 	/* make sure the requested settings are
326 	 * not higher than maximum settings*/
327 	if (max_requested.VOLTAGE_SWING > VOLTAGE_SWING_MAX_LEVEL)
328 		max_requested.VOLTAGE_SWING = VOLTAGE_SWING_MAX_LEVEL;
329 
330 	if (max_requested.PRE_EMPHASIS > PRE_EMPHASIS_MAX_LEVEL)
331 		max_requested.PRE_EMPHASIS = PRE_EMPHASIS_MAX_LEVEL;
332 	if (max_requested.FFE_PRESET.settings.level > DP_FFE_PRESET_MAX_LEVEL)
333 		max_requested.FFE_PRESET.settings.level = DP_FFE_PRESET_MAX_LEVEL;
334 
335 	/* make sure the pre-emphasis matches the voltage swing*/
336 	if (max_requested.PRE_EMPHASIS >
337 		get_max_pre_emphasis_for_voltage_swing(
338 			max_requested.VOLTAGE_SWING))
339 		max_requested.PRE_EMPHASIS =
340 		get_max_pre_emphasis_for_voltage_swing(
341 			max_requested.VOLTAGE_SWING);
342 
343 	for (lane = 0; lane < LANE_COUNT_DP_MAX; lane++) {
344 		lane_settings[lane].VOLTAGE_SWING = max_requested.VOLTAGE_SWING;
345 		lane_settings[lane].PRE_EMPHASIS = max_requested.PRE_EMPHASIS;
346 		lane_settings[lane].FFE_PRESET = max_requested.FFE_PRESET;
347 	}
348 }
349 
dp_hw_to_dpcd_lane_settings(const struct link_training_settings * lt_settings,const struct dc_lane_settings hw_lane_settings[LANE_COUNT_DP_MAX],union dpcd_training_lane dpcd_lane_settings[LANE_COUNT_DP_MAX])350 void dp_hw_to_dpcd_lane_settings(
351 		const struct link_training_settings *lt_settings,
352 		const struct dc_lane_settings hw_lane_settings[LANE_COUNT_DP_MAX],
353 		union dpcd_training_lane dpcd_lane_settings[LANE_COUNT_DP_MAX])
354 {
355 	uint8_t lane = 0;
356 
357 	for (lane = 0; lane < LANE_COUNT_DP_MAX; lane++) {
358 		if (link_dp_get_encoding_format(&lt_settings->link_settings) ==
359 				DP_8b_10b_ENCODING) {
360 			dpcd_lane_settings[lane].bits.VOLTAGE_SWING_SET =
361 					(uint8_t)(hw_lane_settings[lane].VOLTAGE_SWING);
362 			dpcd_lane_settings[lane].bits.PRE_EMPHASIS_SET =
363 					(uint8_t)(hw_lane_settings[lane].PRE_EMPHASIS);
364 			dpcd_lane_settings[lane].bits.MAX_SWING_REACHED =
365 					(hw_lane_settings[lane].VOLTAGE_SWING ==
366 							VOLTAGE_SWING_MAX_LEVEL ? 1 : 0);
367 			dpcd_lane_settings[lane].bits.MAX_PRE_EMPHASIS_REACHED =
368 					(hw_lane_settings[lane].PRE_EMPHASIS ==
369 							PRE_EMPHASIS_MAX_LEVEL ? 1 : 0);
370 		} else if (link_dp_get_encoding_format(&lt_settings->link_settings) ==
371 				DP_128b_132b_ENCODING) {
372 			dpcd_lane_settings[lane].tx_ffe.PRESET_VALUE =
373 					hw_lane_settings[lane].FFE_PRESET.settings.level;
374 		}
375 	}
376 }
377 
get_dpcd_link_rate(const struct dc_link_settings * link_settings)378 uint8_t get_dpcd_link_rate(const struct dc_link_settings *link_settings)
379 {
380 	uint8_t link_rate = 0;
381 	enum dp_link_encoding encoding = link_dp_get_encoding_format(link_settings);
382 
383 	if (encoding == DP_128b_132b_ENCODING)
384 		switch (link_settings->link_rate) {
385 		case LINK_RATE_UHBR10:
386 			link_rate = 0x1;
387 			break;
388 		case LINK_RATE_UHBR20:
389 			link_rate = 0x2;
390 			break;
391 		case LINK_RATE_UHBR13_5:
392 			link_rate = 0x4;
393 			break;
394 		default:
395 			link_rate = 0;
396 			break;
397 		}
398 	else if (encoding == DP_8b_10b_ENCODING)
399 		link_rate = (uint8_t) link_settings->link_rate;
400 	else
401 		link_rate = 0;
402 
403 	return link_rate;
404 }
405 
406 /* Only used for channel equalization */
dp_translate_training_aux_read_interval(uint32_t dpcd_aux_read_interval)407 uint32_t dp_translate_training_aux_read_interval(uint32_t dpcd_aux_read_interval)
408 {
409 	unsigned int aux_rd_interval_us = 400;
410 
411 	switch (dpcd_aux_read_interval) {
412 	case 0x01:
413 		aux_rd_interval_us = 4000;
414 		break;
415 	case 0x02:
416 		aux_rd_interval_us = 8000;
417 		break;
418 	case 0x03:
419 		aux_rd_interval_us = 12000;
420 		break;
421 	case 0x04:
422 		aux_rd_interval_us = 16000;
423 		break;
424 	case 0x05:
425 		aux_rd_interval_us = 32000;
426 		break;
427 	case 0x06:
428 		aux_rd_interval_us = 64000;
429 		break;
430 	default:
431 		break;
432 	}
433 
434 	return aux_rd_interval_us;
435 }
436 
dp_get_cr_failure(enum dc_lane_count ln_count,union lane_status * dpcd_lane_status)437 enum link_training_result dp_get_cr_failure(enum dc_lane_count ln_count,
438 					union lane_status *dpcd_lane_status)
439 {
440 	enum link_training_result result = LINK_TRAINING_SUCCESS;
441 
442 	if (ln_count >= LANE_COUNT_ONE && !dpcd_lane_status[0].bits.CR_DONE_0)
443 		result = LINK_TRAINING_CR_FAIL_LANE0;
444 	else if (ln_count >= LANE_COUNT_TWO && !dpcd_lane_status[1].bits.CR_DONE_0)
445 		result = LINK_TRAINING_CR_FAIL_LANE1;
446 	else if (ln_count >= LANE_COUNT_FOUR && !dpcd_lane_status[2].bits.CR_DONE_0)
447 		result = LINK_TRAINING_CR_FAIL_LANE23;
448 	else if (ln_count >= LANE_COUNT_FOUR && !dpcd_lane_status[3].bits.CR_DONE_0)
449 		result = LINK_TRAINING_CR_FAIL_LANE23;
450 	return result;
451 }
452 
is_repeater(const struct link_training_settings * lt_settings,uint32_t offset)453 bool is_repeater(const struct link_training_settings *lt_settings, uint32_t offset)
454 {
455 	return (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) && (offset != 0);
456 }
457 
dp_is_max_vs_reached(const struct link_training_settings * lt_settings)458 bool dp_is_max_vs_reached(
459 	const struct link_training_settings *lt_settings)
460 {
461 	uint32_t lane;
462 	for (lane = 0; lane <
463 		(uint32_t)(lt_settings->link_settings.lane_count);
464 		lane++) {
465 		if (lt_settings->dpcd_lane_settings[lane].bits.VOLTAGE_SWING_SET
466 			== VOLTAGE_SWING_MAX_LEVEL)
467 			return true;
468 	}
469 	return false;
470 
471 }
472 
dp_is_cr_done(enum dc_lane_count ln_count,union lane_status * dpcd_lane_status)473 bool dp_is_cr_done(enum dc_lane_count ln_count,
474 	union lane_status *dpcd_lane_status)
475 {
476 	bool done = true;
477 	uint32_t lane;
478 	/*LANEx_CR_DONE bits All 1's?*/
479 	for (lane = 0; lane < (uint32_t)(ln_count); lane++) {
480 		if (!dpcd_lane_status[lane].bits.CR_DONE_0)
481 			done = false;
482 	}
483 	return done;
484 
485 }
486 
dp_is_ch_eq_done(enum dc_lane_count ln_count,union lane_status * dpcd_lane_status)487 bool dp_is_ch_eq_done(enum dc_lane_count ln_count,
488 		union lane_status *dpcd_lane_status)
489 {
490 	bool done = true;
491 	uint32_t lane;
492 	for (lane = 0; lane < (uint32_t)(ln_count); lane++)
493 		if (!dpcd_lane_status[lane].bits.CHANNEL_EQ_DONE_0)
494 			done = false;
495 	return done;
496 }
497 
dp_is_symbol_locked(enum dc_lane_count ln_count,union lane_status * dpcd_lane_status)498 bool dp_is_symbol_locked(enum dc_lane_count ln_count,
499 		union lane_status *dpcd_lane_status)
500 {
501 	bool locked = true;
502 	uint32_t lane;
503 	for (lane = 0; lane < (uint32_t)(ln_count); lane++)
504 		if (!dpcd_lane_status[lane].bits.SYMBOL_LOCKED_0)
505 			locked = false;
506 	return locked;
507 }
508 
dp_is_interlane_aligned(union lane_align_status_updated align_status)509 bool dp_is_interlane_aligned(union lane_align_status_updated align_status)
510 {
511 	return align_status.bits.INTERLANE_ALIGN_DONE == 1;
512 }
513 
dp_check_link_loss_status(struct dc_link * link,const struct link_training_settings * link_training_setting)514 enum link_training_result dp_check_link_loss_status(
515 	struct dc_link *link,
516 	const struct link_training_settings *link_training_setting)
517 {
518 	enum link_training_result status = LINK_TRAINING_SUCCESS;
519 	union lane_status lane_status;
520 	union lane_align_status_updated dpcd_lane_status_updated;
521 	uint8_t dpcd_buf[6] = {0};
522 	uint32_t lane;
523 
524 	core_link_read_dpcd(
525 			link,
526 			DP_SINK_COUNT,
527 			(uint8_t *)(dpcd_buf),
528 			sizeof(dpcd_buf));
529 
530 	/*parse lane status*/
531 	for (lane = 0; lane < link->cur_link_settings.lane_count; lane++) {
532 		/*
533 		 * check lanes status
534 		 */
535 		lane_status.raw = dp_get_nibble_at_index(&dpcd_buf[2], lane);
536 		dpcd_lane_status_updated.raw = dpcd_buf[4];
537 
538 		if (!lane_status.bits.CHANNEL_EQ_DONE_0 ||
539 			!lane_status.bits.CR_DONE_0 ||
540 			!lane_status.bits.SYMBOL_LOCKED_0 ||
541 			!dp_is_interlane_aligned(dpcd_lane_status_updated)) {
542 			/* if one of the channel equalization, clock
543 			 * recovery or symbol lock is dropped
544 			 * consider it as (link has been
545 			 * dropped) dp sink status has changed
546 			 */
547 			status = LINK_TRAINING_LINK_LOSS;
548 			break;
549 		}
550 	}
551 
552 	return status;
553 }
554 
dp_get_lane_status_and_lane_adjust(struct dc_link * link,const struct link_training_settings * link_training_setting,union lane_status ln_status[LANE_COUNT_DP_MAX],union lane_align_status_updated * ln_align,union lane_adjust ln_adjust[LANE_COUNT_DP_MAX],uint32_t offset)555 enum dc_status dp_get_lane_status_and_lane_adjust(
556 	struct dc_link *link,
557 	const struct link_training_settings *link_training_setting,
558 	union lane_status ln_status[LANE_COUNT_DP_MAX],
559 	union lane_align_status_updated *ln_align,
560 	union lane_adjust ln_adjust[LANE_COUNT_DP_MAX],
561 	uint32_t offset)
562 {
563 	unsigned int lane01_status_address = DP_LANE0_1_STATUS;
564 	uint8_t lane_adjust_offset = 4;
565 	unsigned int lane01_adjust_address;
566 	uint8_t dpcd_buf[6] = {0};
567 	uint32_t lane;
568 	enum dc_status status;
569 
570 	if (is_repeater(link_training_setting, offset)) {
571 		lane01_status_address =
572 				DP_LANE0_1_STATUS_PHY_REPEATER1 +
573 				((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (offset - 1));
574 		lane_adjust_offset = 3;
575 	}
576 
577 	status = core_link_read_dpcd(
578 		link,
579 		lane01_status_address,
580 		(uint8_t *)(dpcd_buf),
581 		sizeof(dpcd_buf));
582 
583 	if (status != DC_OK) {
584 		DC_LOG_HW_LINK_TRAINING("%s:\n Failed to read from address 0x%X,"
585 			" keep current lane status and lane adjust unchanged",
586 			__func__,
587 			lane01_status_address);
588 		return status;
589 	}
590 
591 	for (lane = 0; lane <
592 		(uint32_t)(link_training_setting->link_settings.lane_count);
593 		lane++) {
594 
595 		ln_status[lane].raw =
596 			dp_get_nibble_at_index(&dpcd_buf[0], lane);
597 		ln_adjust[lane].raw =
598 			dp_get_nibble_at_index(&dpcd_buf[lane_adjust_offset], lane);
599 	}
600 
601 	ln_align->raw = dpcd_buf[2];
602 
603 	if (is_repeater(link_training_setting, offset)) {
604 		DC_LOG_HW_LINK_TRAINING("%s:\n LTTPR Repeater ID: %d\n"
605 				" 0x%X Lane01Status = %x\n 0x%X Lane23Status = %x\n ",
606 			__func__,
607 			offset,
608 			lane01_status_address, dpcd_buf[0],
609 			lane01_status_address + 1, dpcd_buf[1]);
610 
611 		lane01_adjust_address = DP_ADJUST_REQUEST_LANE0_1_PHY_REPEATER1 +
612 				((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (offset - 1));
613 
614 		DC_LOG_HW_LINK_TRAINING("%s:\n LTTPR Repeater ID: %d\n"
615 				" 0x%X Lane01AdjustRequest = %x\n 0x%X Lane23AdjustRequest = %x\n",
616 					__func__,
617 					offset,
618 					lane01_adjust_address,
619 					dpcd_buf[lane_adjust_offset],
620 					lane01_adjust_address + 1,
621 					dpcd_buf[lane_adjust_offset + 1]);
622 	} else {
623 		DC_LOG_HW_LINK_TRAINING("%s:\n 0x%X Lane01Status = %x\n 0x%X Lane23Status = %x\n ",
624 			__func__,
625 			lane01_status_address, dpcd_buf[0],
626 			lane01_status_address + 1, dpcd_buf[1]);
627 
628 		lane01_adjust_address = DP_ADJUST_REQUEST_LANE0_1;
629 
630 		DC_LOG_HW_LINK_TRAINING("%s:\n 0x%X Lane01AdjustRequest = %x\n 0x%X Lane23AdjustRequest = %x\n",
631 			__func__,
632 			lane01_adjust_address,
633 			dpcd_buf[lane_adjust_offset],
634 			lane01_adjust_address + 1,
635 			dpcd_buf[lane_adjust_offset + 1]);
636 	}
637 
638 	return status;
639 }
640 
override_lane_settings(const struct link_training_settings * lt_settings,struct dc_lane_settings lane_settings[LANE_COUNT_DP_MAX])641 static void override_lane_settings(const struct link_training_settings *lt_settings,
642 		struct dc_lane_settings lane_settings[LANE_COUNT_DP_MAX])
643 {
644 	uint32_t lane;
645 
646 	if (lt_settings->voltage_swing == NULL &&
647 			lt_settings->pre_emphasis == NULL &&
648 			lt_settings->ffe_preset == NULL &&
649 			lt_settings->post_cursor2 == NULL)
650 
651 		return;
652 
653 	for (lane = 0; lane < LANE_COUNT_DP_MAX; lane++) {
654 		if (lt_settings->voltage_swing)
655 			lane_settings[lane].VOLTAGE_SWING = *lt_settings->voltage_swing;
656 		if (lt_settings->pre_emphasis)
657 			lane_settings[lane].PRE_EMPHASIS = *lt_settings->pre_emphasis;
658 		if (lt_settings->post_cursor2)
659 			lane_settings[lane].POST_CURSOR2 = *lt_settings->post_cursor2;
660 		if (lt_settings->ffe_preset)
661 			lane_settings[lane].FFE_PRESET = *lt_settings->ffe_preset;
662 	}
663 }
664 
dp_get_lttpr_mode_override(struct dc_link * link,enum lttpr_mode * override)665 void dp_get_lttpr_mode_override(struct dc_link *link, enum lttpr_mode *override)
666 {
667 	if (!dp_is_lttpr_present(link))
668 		return;
669 
670 	if (link->dc->debug.lttpr_mode_override == LTTPR_MODE_TRANSPARENT) {
671 		*override = LTTPR_MODE_TRANSPARENT;
672 	} else if (link->dc->debug.lttpr_mode_override == LTTPR_MODE_NON_TRANSPARENT) {
673 		*override = LTTPR_MODE_NON_TRANSPARENT;
674 	} else if (link->dc->debug.lttpr_mode_override == LTTPR_MODE_NON_LTTPR) {
675 		*override = LTTPR_MODE_NON_LTTPR;
676 	}
677 	DC_LOG_DC("lttpr_mode_override chose LTTPR_MODE = %d\n", (uint8_t)(*override));
678 }
679 
override_training_settings(struct dc_link * link,const struct dc_link_training_overrides * overrides,struct link_training_settings * lt_settings)680 void override_training_settings(
681 		struct dc_link *link,
682 		const struct dc_link_training_overrides *overrides,
683 		struct link_training_settings *lt_settings)
684 {
685 	uint32_t lane;
686 
687 	/* Override link spread */
688 	if (!link->dp_ss_off && overrides->downspread != NULL)
689 		lt_settings->link_settings.link_spread = *overrides->downspread ?
690 				LINK_SPREAD_05_DOWNSPREAD_30KHZ
691 				: LINK_SPREAD_DISABLED;
692 
693 	/* Override lane settings */
694 	if (overrides->voltage_swing != NULL)
695 		lt_settings->voltage_swing = overrides->voltage_swing;
696 	if (overrides->pre_emphasis != NULL)
697 		lt_settings->pre_emphasis = overrides->pre_emphasis;
698 	if (overrides->post_cursor2 != NULL)
699 		lt_settings->post_cursor2 = overrides->post_cursor2;
700 	if (link->wa_flags.force_dp_ffe_preset && !dp_is_lttpr_present(link))
701 		lt_settings->ffe_preset = &link->forced_dp_ffe_preset;
702 	if (overrides->ffe_preset != NULL)
703 		lt_settings->ffe_preset = overrides->ffe_preset;
704 	/* Override HW lane settings with BIOS forced values if present */
705 	if ((link->chip_caps & EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) &&
706 			lt_settings->lttpr_mode == LTTPR_MODE_TRANSPARENT) {
707 		lt_settings->voltage_swing = &link->bios_forced_drive_settings.VOLTAGE_SWING;
708 		lt_settings->pre_emphasis = &link->bios_forced_drive_settings.PRE_EMPHASIS;
709 		lt_settings->always_match_dpcd_with_hw_lane_settings = false;
710 	}
711 	for (lane = 0; lane < LANE_COUNT_DP_MAX; lane++) {
712 		lt_settings->hw_lane_settings[lane].VOLTAGE_SWING =
713 			lt_settings->voltage_swing != NULL ?
714 			*lt_settings->voltage_swing :
715 			VOLTAGE_SWING_LEVEL0;
716 		lt_settings->hw_lane_settings[lane].PRE_EMPHASIS =
717 			lt_settings->pre_emphasis != NULL ?
718 			*lt_settings->pre_emphasis
719 			: PRE_EMPHASIS_DISABLED;
720 		lt_settings->hw_lane_settings[lane].POST_CURSOR2 =
721 			lt_settings->post_cursor2 != NULL ?
722 			*lt_settings->post_cursor2
723 			: POST_CURSOR2_DISABLED;
724 	}
725 
726 	if (lt_settings->always_match_dpcd_with_hw_lane_settings)
727 		dp_hw_to_dpcd_lane_settings(lt_settings,
728 				lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
729 
730 	/* Override training timings */
731 	if (overrides->cr_pattern_time != NULL)
732 		lt_settings->cr_pattern_time = *overrides->cr_pattern_time;
733 	if (overrides->eq_pattern_time != NULL)
734 		lt_settings->eq_pattern_time = *overrides->eq_pattern_time;
735 	if (overrides->pattern_for_cr != NULL)
736 		lt_settings->pattern_for_cr = *overrides->pattern_for_cr;
737 	if (overrides->pattern_for_eq != NULL)
738 		lt_settings->pattern_for_eq = *overrides->pattern_for_eq;
739 	if (overrides->enhanced_framing != NULL)
740 		lt_settings->enhanced_framing = *overrides->enhanced_framing;
741 	if (link->preferred_training_settings.fec_enable != NULL)
742 		lt_settings->should_set_fec_ready = *link->preferred_training_settings.fec_enable;
743 
744 	/* Check DP tunnel LTTPR mode debug option. */
745 	if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA && link->dc->debug.dpia_debug.bits.force_non_lttpr)
746 		lt_settings->lttpr_mode = LTTPR_MODE_NON_LTTPR;
747 
748 	dp_get_lttpr_mode_override(link, &lt_settings->lttpr_mode);
749 
750 }
751 
decide_cr_training_pattern(const struct dc_link_settings * link_settings)752 enum dc_dp_training_pattern decide_cr_training_pattern(
753 		const struct dc_link_settings *link_settings)
754 {
755 	switch (link_dp_get_encoding_format(link_settings)) {
756 	case DP_8b_10b_ENCODING:
757 	default:
758 		return DP_TRAINING_PATTERN_SEQUENCE_1;
759 	case DP_128b_132b_ENCODING:
760 		return DP_128b_132b_TPS1;
761 	}
762 }
763 
decide_eq_training_pattern(struct dc_link * link,const struct dc_link_settings * link_settings)764 enum dc_dp_training_pattern decide_eq_training_pattern(struct dc_link *link,
765 		const struct dc_link_settings *link_settings)
766 {
767 	struct link_encoder *link_enc;
768 	struct encoder_feature_support *enc_caps;
769 	struct dpcd_caps *rx_caps = &link->dpcd_caps;
770 	enum dc_dp_training_pattern pattern = DP_TRAINING_PATTERN_SEQUENCE_2;
771 
772 	link_enc = link_enc_cfg_get_link_enc(link);
773 	ASSERT(link_enc);
774 	enc_caps = &link_enc->features;
775 
776 	switch (link_dp_get_encoding_format(link_settings)) {
777 	case DP_8b_10b_ENCODING:
778 		if (enc_caps->flags.bits.IS_TPS4_CAPABLE &&
779 				rx_caps->max_down_spread.bits.TPS4_SUPPORTED)
780 			pattern = DP_TRAINING_PATTERN_SEQUENCE_4;
781 		else if (enc_caps->flags.bits.IS_TPS3_CAPABLE &&
782 				rx_caps->max_ln_count.bits.TPS3_SUPPORTED)
783 			pattern = DP_TRAINING_PATTERN_SEQUENCE_3;
784 		else
785 			pattern = DP_TRAINING_PATTERN_SEQUENCE_2;
786 		break;
787 	case DP_128b_132b_ENCODING:
788 		pattern = DP_128b_132b_TPS2;
789 		break;
790 	default:
791 		pattern = DP_TRAINING_PATTERN_SEQUENCE_2;
792 		break;
793 	}
794 	return pattern;
795 }
796 
dp_decide_lttpr_mode(struct dc_link * link,struct dc_link_settings * link_setting)797 enum lttpr_mode dp_decide_lttpr_mode(struct dc_link *link,
798 		struct dc_link_settings *link_setting)
799 {
800 	enum dp_link_encoding encoding = link_dp_get_encoding_format(link_setting);
801 
802 	if (encoding == DP_8b_10b_ENCODING)
803 		return dp_decide_8b_10b_lttpr_mode(link);
804 	else if (encoding == DP_128b_132b_ENCODING)
805 		return dp_decide_128b_132b_lttpr_mode(link);
806 
807 	ASSERT(0);
808 	return LTTPR_MODE_NON_LTTPR;
809 }
810 
dp_decide_lane_settings(const struct link_training_settings * lt_settings,const union lane_adjust ln_adjust[LANE_COUNT_DP_MAX],struct dc_lane_settings hw_lane_settings[LANE_COUNT_DP_MAX],union dpcd_training_lane * dpcd_lane_settings)811 void dp_decide_lane_settings(
812 		const struct link_training_settings *lt_settings,
813 		const union lane_adjust ln_adjust[LANE_COUNT_DP_MAX],
814 		struct dc_lane_settings hw_lane_settings[LANE_COUNT_DP_MAX],
815 		union dpcd_training_lane *dpcd_lane_settings)
816 {
817 	uint32_t lane;
818 
819 	for (lane = 0; lane < LANE_COUNT_DP_MAX; lane++) {
820 		if (link_dp_get_encoding_format(&lt_settings->link_settings) ==
821 				DP_8b_10b_ENCODING) {
822 			hw_lane_settings[lane].VOLTAGE_SWING =
823 					(enum dc_voltage_swing)(ln_adjust[lane].bits.
824 							VOLTAGE_SWING_LANE);
825 			hw_lane_settings[lane].PRE_EMPHASIS =
826 					(enum dc_pre_emphasis)(ln_adjust[lane].bits.
827 							PRE_EMPHASIS_LANE);
828 		} else if (link_dp_get_encoding_format(&lt_settings->link_settings) ==
829 				DP_128b_132b_ENCODING) {
830 			hw_lane_settings[lane].FFE_PRESET.raw =
831 					ln_adjust[lane].tx_ffe.PRESET_VALUE;
832 		}
833 	}
834 	dp_hw_to_dpcd_lane_settings(lt_settings, hw_lane_settings, dpcd_lane_settings);
835 
836 	if (lt_settings->disallow_per_lane_settings) {
837 		/* we find the maximum of the requested settings across all lanes*/
838 		/* and set this maximum for all lanes*/
839 		maximize_lane_settings(lt_settings, hw_lane_settings);
840 		override_lane_settings(lt_settings, hw_lane_settings);
841 
842 		if (lt_settings->always_match_dpcd_with_hw_lane_settings)
843 			dp_hw_to_dpcd_lane_settings(lt_settings, hw_lane_settings, dpcd_lane_settings);
844 	}
845 
846 }
847 
dp_decide_training_settings(struct dc_link * link,const struct dc_link_settings * link_settings,struct link_training_settings * lt_settings)848 void dp_decide_training_settings(
849 		struct dc_link *link,
850 		const struct dc_link_settings *link_settings,
851 		struct link_training_settings *lt_settings)
852 {
853 	if (link_dp_get_encoding_format(link_settings) == DP_8b_10b_ENCODING)
854 		decide_8b_10b_training_settings(link, link_settings, lt_settings);
855 	else if (link_dp_get_encoding_format(link_settings) == DP_128b_132b_ENCODING)
856 		decide_128b_132b_training_settings(link, link_settings, lt_settings);
857 }
858 
859 
configure_lttpr_mode_transparent(struct dc_link * link)860 enum dc_status configure_lttpr_mode_transparent(struct dc_link *link)
861 {
862 	uint8_t repeater_mode = DP_PHY_REPEATER_MODE_TRANSPARENT;
863 
864 	DC_LOG_HW_LINK_TRAINING("%s\n Set LTTPR to Transparent Mode\n", __func__);
865 	return core_link_write_dpcd(link,
866 			DP_PHY_REPEATER_MODE,
867 			(uint8_t *)&repeater_mode,
868 			sizeof(repeater_mode));
869 }
870 
configure_lttpr_mode_non_transparent(struct dc_link * link,const struct link_training_settings * lt_settings)871 static enum dc_status configure_lttpr_mode_non_transparent(
872 		struct dc_link *link,
873 		const struct link_training_settings *lt_settings)
874 {
875 	/* aux timeout is already set to extended */
876 	/* RESET/SET lttpr mode to enable non transparent mode */
877 	uint8_t repeater_cnt;
878 	uint32_t aux_interval_address;
879 	uint8_t repeater_id;
880 	enum dc_status result = DC_ERROR_UNEXPECTED;
881 	uint8_t repeater_mode = DP_PHY_REPEATER_MODE_TRANSPARENT;
882 	const struct dc *dc = link->dc;
883 
884 	enum dp_link_encoding encoding = dc->link_srv->dp_get_encoding_format(&lt_settings->link_settings);
885 
886 	if (encoding == DP_8b_10b_ENCODING) {
887 		DC_LOG_HW_LINK_TRAINING("%s\n Set LTTPR to Transparent Mode\n", __func__);
888 		result = core_link_write_dpcd(link,
889 				DP_PHY_REPEATER_MODE,
890 				(uint8_t *)&repeater_mode,
891 				sizeof(repeater_mode));
892 
893 	}
894 
895 	if (result == DC_OK) {
896 		link->dpcd_caps.lttpr_caps.mode = repeater_mode;
897 	}
898 
899 	if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) {
900 
901 		DC_LOG_HW_LINK_TRAINING("%s\n Set LTTPR to Non Transparent Mode\n", __func__);
902 
903 		repeater_mode = DP_PHY_REPEATER_MODE_NON_TRANSPARENT;
904 		result = core_link_write_dpcd(link,
905 				DP_PHY_REPEATER_MODE,
906 				(uint8_t *)&repeater_mode,
907 				sizeof(repeater_mode));
908 
909 		if (result == DC_OK) {
910 			link->dpcd_caps.lttpr_caps.mode = repeater_mode;
911 		}
912 
913 		if (encoding == DP_8b_10b_ENCODING) {
914 			repeater_cnt = dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
915 
916 			/* Driver does not need to train the first hop. Skip DPCD read and clear
917 			 * AUX_RD_INTERVAL for DPTX-to-DPIA hop.
918 			 */
919 			if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA && repeater_cnt > 0 && repeater_cnt < MAX_REPEATER_CNT)
920 				link->dpcd_caps.lttpr_caps.aux_rd_interval[--repeater_cnt] = 0;
921 
922 			for (repeater_id = repeater_cnt; repeater_id > 0 && repeater_id < MAX_REPEATER_CNT; repeater_id--) {
923 				aux_interval_address = DP_TRAINING_AUX_RD_INTERVAL_PHY_REPEATER1 +
924 						((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (repeater_id - 1));
925 				core_link_read_dpcd(
926 						link,
927 						aux_interval_address,
928 						(uint8_t *)&link->dpcd_caps.lttpr_caps.aux_rd_interval[repeater_id - 1],
929 						sizeof(link->dpcd_caps.lttpr_caps.aux_rd_interval[repeater_id - 1]));
930 				link->dpcd_caps.lttpr_caps.aux_rd_interval[repeater_id - 1] &= 0x7F;
931 			}
932 		}
933 	}
934 
935 	return result;
936 }
937 
dpcd_configure_lttpr_mode(struct dc_link * link,struct link_training_settings * lt_settings)938 enum dc_status dpcd_configure_lttpr_mode(struct dc_link *link, struct link_training_settings *lt_settings)
939 {
940 	enum dc_status status = DC_OK;
941 
942 	if (lt_settings->lttpr_mode == LTTPR_MODE_TRANSPARENT)
943 		status = configure_lttpr_mode_transparent(link);
944 
945 	else if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT)
946 		status = configure_lttpr_mode_non_transparent(link, lt_settings);
947 
948 	return status;
949 }
950 
repeater_training_done(struct dc_link * link,uint32_t offset)951 void repeater_training_done(struct dc_link *link, uint32_t offset)
952 {
953 	union dpcd_training_pattern dpcd_pattern = {0};
954 
955 	const uint32_t dpcd_base_lt_offset =
956 			DP_TRAINING_PATTERN_SET_PHY_REPEATER1 +
957 				((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (offset - 1));
958 	/* Set training not in progress*/
959 	dpcd_pattern.v1_4.TRAINING_PATTERN_SET = DPCD_TRAINING_PATTERN_VIDEOIDLE;
960 
961 	core_link_write_dpcd(
962 		link,
963 		dpcd_base_lt_offset,
964 		&dpcd_pattern.raw,
965 		1);
966 
967 	DC_LOG_HW_LINK_TRAINING("%s\n LTTPR Id: %d 0x%X pattern = %x\n",
968 		__func__,
969 		offset,
970 		dpcd_base_lt_offset,
971 		dpcd_pattern.v1_4.TRAINING_PATTERN_SET);
972 }
973 
dpcd_exit_training_mode(struct dc_link * link,enum dp_link_encoding encoding)974 static void dpcd_exit_training_mode(struct dc_link *link, enum dp_link_encoding encoding)
975 {
976 	uint8_t sink_status = 0;
977 	uint8_t i;
978 
979 	/* clear training pattern set */
980 	dpcd_set_training_pattern(link, DP_TRAINING_PATTERN_VIDEOIDLE);
981 
982 	if (encoding == DP_128b_132b_ENCODING) {
983 		/* poll for intra-hop disable */
984 		for (i = 0; i < 10; i++) {
985 			if ((core_link_read_dpcd(link, DP_SINK_STATUS, &sink_status, 1) == DC_OK) &&
986 					(sink_status & DP_INTRA_HOP_AUX_REPLY_INDICATION) == 0)
987 				break;
988 			fsleep(1000);
989 		}
990 	}
991 }
992 
dpcd_configure_channel_coding(struct dc_link * link,struct link_training_settings * lt_settings)993 enum dc_status dpcd_configure_channel_coding(struct dc_link *link,
994 		struct link_training_settings *lt_settings)
995 {
996 	enum dp_link_encoding encoding =
997 			link_dp_get_encoding_format(
998 					&lt_settings->link_settings);
999 	enum dc_status status;
1000 
1001 	status = core_link_write_dpcd(
1002 			link,
1003 			DP_MAIN_LINK_CHANNEL_CODING_SET,
1004 			(uint8_t *) &encoding,
1005 			1);
1006 	DC_LOG_HW_LINK_TRAINING("%s:\n 0x%X MAIN_LINK_CHANNEL_CODING_SET = %x\n",
1007 					__func__,
1008 					DP_MAIN_LINK_CHANNEL_CODING_SET,
1009 					encoding);
1010 
1011 	return status;
1012 }
1013 
dpcd_set_training_pattern(struct dc_link * link,enum dc_dp_training_pattern training_pattern)1014 void dpcd_set_training_pattern(
1015 	struct dc_link *link,
1016 	enum dc_dp_training_pattern training_pattern)
1017 {
1018 	union dpcd_training_pattern dpcd_pattern = {0};
1019 
1020 	dpcd_pattern.v1_4.TRAINING_PATTERN_SET =
1021 			dp_training_pattern_to_dpcd_training_pattern(
1022 					link, training_pattern);
1023 
1024 	core_link_write_dpcd(
1025 		link,
1026 		DP_TRAINING_PATTERN_SET,
1027 		&dpcd_pattern.raw,
1028 		1);
1029 
1030 	DC_LOG_HW_LINK_TRAINING("%s\n %x pattern = %x\n",
1031 		__func__,
1032 		DP_TRAINING_PATTERN_SET,
1033 		dpcd_pattern.v1_4.TRAINING_PATTERN_SET);
1034 }
1035 
dpcd_set_link_settings(struct dc_link * link,const struct link_training_settings * lt_settings)1036 enum dc_status dpcd_set_link_settings(
1037 	struct dc_link *link,
1038 	const struct link_training_settings *lt_settings)
1039 {
1040 	uint8_t rate;
1041 	enum dc_status status;
1042 
1043 	union down_spread_ctrl downspread = {0};
1044 	union lane_count_set lane_count_set = {0};
1045 
1046 	downspread.raw = (uint8_t)
1047 	(lt_settings->link_settings.link_spread);
1048 
1049 	lane_count_set.bits.LANE_COUNT_SET =
1050 	lt_settings->link_settings.lane_count;
1051 
1052 	lane_count_set.bits.ENHANCED_FRAMING = lt_settings->enhanced_framing;
1053 	lane_count_set.bits.POST_LT_ADJ_REQ_GRANTED = 0;
1054 
1055 
1056 	if (link->ep_type == DISPLAY_ENDPOINT_PHY &&
1057 			lt_settings->pattern_for_eq < DP_TRAINING_PATTERN_SEQUENCE_4) {
1058 		lane_count_set.bits.POST_LT_ADJ_REQ_GRANTED =
1059 				link->dpcd_caps.max_ln_count.bits.POST_LT_ADJ_REQ_SUPPORTED;
1060 	}
1061 
1062 	status = core_link_write_dpcd(link, DP_DOWNSPREAD_CTRL,
1063 		&downspread.raw, sizeof(downspread));
1064 
1065 	status = core_link_write_dpcd(link, DP_LANE_COUNT_SET,
1066 		&lane_count_set.raw, 1);
1067 
1068 	if (link->dpcd_caps.dpcd_rev.raw >= DPCD_REV_13 &&
1069 			lt_settings->link_settings.use_link_rate_set == true) {
1070 		rate = 0;
1071 		/* WA for some MUX chips that will power down with eDP and lose supported
1072 		 * link rate set for eDP 1.4. Source reads DPCD 0x010 again to ensure
1073 		 * MUX chip gets link rate set back before link training.
1074 		 */
1075 		if (link->connector_signal == SIGNAL_TYPE_EDP) {
1076 			uint8_t supported_link_rates[16];
1077 
1078 			core_link_read_dpcd(link, DP_SUPPORTED_LINK_RATES,
1079 					supported_link_rates, sizeof(supported_link_rates));
1080 		}
1081 		status = core_link_write_dpcd(link, DP_LINK_BW_SET, &rate, 1);
1082 		status = core_link_write_dpcd(link, DP_LINK_RATE_SET,
1083 				&lt_settings->link_settings.link_rate_set, 1);
1084 	} else {
1085 		rate = get_dpcd_link_rate(&lt_settings->link_settings);
1086 
1087 		status = core_link_write_dpcd(link, DP_LINK_BW_SET, &rate, 1);
1088 	}
1089 
1090 	if (rate) {
1091 		DC_LOG_HW_LINK_TRAINING("%s\n %x rate = %x\n %x lane = %x framing = %x\n %x spread = %x\n",
1092 			__func__,
1093 			DP_LINK_BW_SET,
1094 			lt_settings->link_settings.link_rate,
1095 			DP_LANE_COUNT_SET,
1096 			lt_settings->link_settings.lane_count,
1097 			lt_settings->enhanced_framing,
1098 			DP_DOWNSPREAD_CTRL,
1099 			lt_settings->link_settings.link_spread);
1100 	} else {
1101 		DC_LOG_HW_LINK_TRAINING("%s\n %x rate set = %x\n %x lane = %x framing = %x\n %x spread = %x\n",
1102 			__func__,
1103 			DP_LINK_RATE_SET,
1104 			lt_settings->link_settings.link_rate_set,
1105 			DP_LANE_COUNT_SET,
1106 			lt_settings->link_settings.lane_count,
1107 			lt_settings->enhanced_framing,
1108 			DP_DOWNSPREAD_CTRL,
1109 			lt_settings->link_settings.link_spread);
1110 	}
1111 
1112 	return status;
1113 }
1114 
dpcd_set_lane_settings(struct dc_link * link,const struct link_training_settings * link_training_setting,uint32_t offset)1115 enum dc_status dpcd_set_lane_settings(
1116 	struct dc_link *link,
1117 	const struct link_training_settings *link_training_setting,
1118 	uint32_t offset)
1119 {
1120 	unsigned int lane0_set_address;
1121 	enum dc_status status;
1122 	lane0_set_address = DP_TRAINING_LANE0_SET;
1123 
1124 	if (is_repeater(link_training_setting, offset))
1125 		lane0_set_address = DP_TRAINING_LANE0_SET_PHY_REPEATER1 +
1126 		((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (offset - 1));
1127 
1128 	status = core_link_write_dpcd(link,
1129 		lane0_set_address,
1130 		(uint8_t *)(link_training_setting->dpcd_lane_settings),
1131 		link_training_setting->link_settings.lane_count);
1132 
1133 	if (is_repeater(link_training_setting, offset)) {
1134 		DC_LOG_HW_LINK_TRAINING("%s\n LTTPR Repeater ID: %d\n"
1135 				" 0x%X VS set = %x  PE set = %x max VS Reached = %x  max PE Reached = %x\n",
1136 			__func__,
1137 			offset,
1138 			lane0_set_address,
1139 			link_training_setting->dpcd_lane_settings[0].bits.VOLTAGE_SWING_SET,
1140 			link_training_setting->dpcd_lane_settings[0].bits.PRE_EMPHASIS_SET,
1141 			link_training_setting->dpcd_lane_settings[0].bits.MAX_SWING_REACHED,
1142 			link_training_setting->dpcd_lane_settings[0].bits.MAX_PRE_EMPHASIS_REACHED);
1143 
1144 	} else {
1145 		DC_LOG_HW_LINK_TRAINING("%s\n 0x%X VS set = %x  PE set = %x max VS Reached = %x  max PE Reached = %x\n",
1146 			__func__,
1147 			lane0_set_address,
1148 			link_training_setting->dpcd_lane_settings[0].bits.VOLTAGE_SWING_SET,
1149 			link_training_setting->dpcd_lane_settings[0].bits.PRE_EMPHASIS_SET,
1150 			link_training_setting->dpcd_lane_settings[0].bits.MAX_SWING_REACHED,
1151 			link_training_setting->dpcd_lane_settings[0].bits.MAX_PRE_EMPHASIS_REACHED);
1152 	}
1153 
1154 	return status;
1155 }
1156 
dpcd_set_lt_pattern_and_lane_settings(struct dc_link * link,const struct link_training_settings * lt_settings,enum dc_dp_training_pattern pattern,uint32_t offset)1157 void dpcd_set_lt_pattern_and_lane_settings(
1158 	struct dc_link *link,
1159 	const struct link_training_settings *lt_settings,
1160 	enum dc_dp_training_pattern pattern,
1161 	uint32_t offset)
1162 {
1163 	uint32_t dpcd_base_lt_offset;
1164 	uint8_t dpcd_lt_buffer[5] = {0};
1165 	union dpcd_training_pattern dpcd_pattern = {0};
1166 	uint32_t size_in_bytes;
1167 	bool edp_workaround = false; /* TODO link_prop.INTERNAL */
1168 	dpcd_base_lt_offset = DP_TRAINING_PATTERN_SET;
1169 
1170 	if (is_repeater(lt_settings, offset))
1171 		dpcd_base_lt_offset = DP_TRAINING_PATTERN_SET_PHY_REPEATER1 +
1172 			((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (offset - 1));
1173 
1174 	/*****************************************************************
1175 	* DpcdAddress_TrainingPatternSet
1176 	*****************************************************************/
1177 	dpcd_pattern.v1_4.TRAINING_PATTERN_SET =
1178 		dp_training_pattern_to_dpcd_training_pattern(link, pattern);
1179 
1180 	dpcd_pattern.v1_4.SCRAMBLING_DISABLE =
1181 		dp_initialize_scrambling_data_symbols(link, pattern);
1182 
1183 	dpcd_lt_buffer[DP_TRAINING_PATTERN_SET - DP_TRAINING_PATTERN_SET]
1184 		= dpcd_pattern.raw;
1185 
1186 	if (is_repeater(lt_settings, offset)) {
1187 		DC_LOG_HW_LINK_TRAINING("%s\n LTTPR Repeater ID: %d\n 0x%X pattern = %x\n",
1188 			__func__,
1189 			offset,
1190 			dpcd_base_lt_offset,
1191 			dpcd_pattern.v1_4.TRAINING_PATTERN_SET);
1192 	} else {
1193 		DC_LOG_HW_LINK_TRAINING("%s\n 0x%X pattern = %x\n",
1194 			__func__,
1195 			dpcd_base_lt_offset,
1196 			dpcd_pattern.v1_4.TRAINING_PATTERN_SET);
1197 	}
1198 
1199 	/* concatenate everything into one buffer*/
1200 	size_in_bytes = lt_settings->link_settings.lane_count *
1201 			sizeof(lt_settings->dpcd_lane_settings[0]);
1202 
1203 	 // 0x00103 - 0x00102
1204 	memmove(
1205 		&dpcd_lt_buffer[DP_TRAINING_LANE0_SET - DP_TRAINING_PATTERN_SET],
1206 		lt_settings->dpcd_lane_settings,
1207 		size_in_bytes);
1208 
1209 	if (is_repeater(lt_settings, offset)) {
1210 		if (link_dp_get_encoding_format(&lt_settings->link_settings) ==
1211 				DP_128b_132b_ENCODING)
1212 			DC_LOG_HW_LINK_TRAINING("%s:\n LTTPR Repeater ID: %d\n"
1213 					" 0x%X TX_FFE_PRESET_VALUE = %x\n",
1214 					__func__,
1215 					offset,
1216 					dpcd_base_lt_offset,
1217 					lt_settings->dpcd_lane_settings[0].tx_ffe.PRESET_VALUE);
1218 		else if (link_dp_get_encoding_format(&lt_settings->link_settings) ==
1219 				DP_8b_10b_ENCODING)
1220 		DC_LOG_HW_LINK_TRAINING("%s:\n LTTPR Repeater ID: %d\n"
1221 				" 0x%X VS set = %x PE set = %x max VS Reached = %x  max PE Reached = %x\n",
1222 			__func__,
1223 			offset,
1224 			dpcd_base_lt_offset,
1225 			lt_settings->dpcd_lane_settings[0].bits.VOLTAGE_SWING_SET,
1226 			lt_settings->dpcd_lane_settings[0].bits.PRE_EMPHASIS_SET,
1227 			lt_settings->dpcd_lane_settings[0].bits.MAX_SWING_REACHED,
1228 			lt_settings->dpcd_lane_settings[0].bits.MAX_PRE_EMPHASIS_REACHED);
1229 	} else {
1230 		if (link_dp_get_encoding_format(&lt_settings->link_settings) ==
1231 				DP_128b_132b_ENCODING)
1232 			DC_LOG_HW_LINK_TRAINING("%s:\n 0x%X TX_FFE_PRESET_VALUE = %x\n",
1233 					__func__,
1234 					dpcd_base_lt_offset,
1235 					lt_settings->dpcd_lane_settings[0].tx_ffe.PRESET_VALUE);
1236 		else if (link_dp_get_encoding_format(&lt_settings->link_settings) ==
1237 				DP_8b_10b_ENCODING)
1238 			DC_LOG_HW_LINK_TRAINING("%s:\n 0x%X VS set = %x  PE set = %x max VS Reached = %x  max PE Reached = %x\n",
1239 					__func__,
1240 					dpcd_base_lt_offset,
1241 					lt_settings->dpcd_lane_settings[0].bits.VOLTAGE_SWING_SET,
1242 					lt_settings->dpcd_lane_settings[0].bits.PRE_EMPHASIS_SET,
1243 					lt_settings->dpcd_lane_settings[0].bits.MAX_SWING_REACHED,
1244 					lt_settings->dpcd_lane_settings[0].bits.MAX_PRE_EMPHASIS_REACHED);
1245 	}
1246 	if (edp_workaround) {
1247 		/* for eDP write in 2 parts because the 5-byte burst is
1248 		* causing issues on some eDP panels (EPR#366724)
1249 		*/
1250 		core_link_write_dpcd(
1251 			link,
1252 			DP_TRAINING_PATTERN_SET,
1253 			&dpcd_pattern.raw,
1254 			sizeof(dpcd_pattern.raw));
1255 
1256 		core_link_write_dpcd(
1257 			link,
1258 			DP_TRAINING_LANE0_SET,
1259 			(uint8_t *)(lt_settings->dpcd_lane_settings),
1260 			size_in_bytes);
1261 
1262 	} else if (link_dp_get_encoding_format(&lt_settings->link_settings) ==
1263 			DP_128b_132b_ENCODING) {
1264 		core_link_write_dpcd(
1265 				link,
1266 				dpcd_base_lt_offset,
1267 				dpcd_lt_buffer,
1268 				sizeof(dpcd_lt_buffer));
1269 	} else
1270 		/* write it all in (1 + number-of-lanes)-byte burst*/
1271 		core_link_write_dpcd(
1272 				link,
1273 				dpcd_base_lt_offset,
1274 				dpcd_lt_buffer,
1275 				size_in_bytes + sizeof(dpcd_pattern.raw));
1276 }
1277 
start_clock_recovery_pattern_early(struct dc_link * link,const struct link_resource * link_res,struct link_training_settings * lt_settings,uint32_t offset)1278 void start_clock_recovery_pattern_early(struct dc_link *link,
1279 		const struct link_resource *link_res,
1280 		struct link_training_settings *lt_settings,
1281 		uint32_t offset)
1282 {
1283 	DC_LOG_HW_LINK_TRAINING("%s\n GPU sends TPS1. Wait 400us.\n",
1284 			__func__);
1285 	dp_set_hw_training_pattern(link, link_res, lt_settings->pattern_for_cr, offset);
1286 	dp_set_hw_lane_settings(link, link_res, lt_settings, offset);
1287 	udelay(400);
1288 }
1289 
dp_set_hw_test_pattern(struct dc_link * link,const struct link_resource * link_res,enum dp_test_pattern test_pattern,uint8_t * custom_pattern,uint32_t custom_pattern_size)1290 void dp_set_hw_test_pattern(
1291 	struct dc_link *link,
1292 	const struct link_resource *link_res,
1293 	enum dp_test_pattern test_pattern,
1294 	uint8_t *custom_pattern,
1295 	uint32_t custom_pattern_size)
1296 {
1297 	const struct link_hwss *link_hwss = get_link_hwss(link, link_res);
1298 	struct encoder_set_dp_phy_pattern_param pattern_param = {0};
1299 
1300 	pattern_param.dp_phy_pattern = test_pattern;
1301 	pattern_param.custom_pattern = custom_pattern;
1302 	pattern_param.custom_pattern_size = custom_pattern_size;
1303 	pattern_param.dp_panel_mode = dp_get_panel_mode(link);
1304 
1305 	if (link_hwss->ext.set_dp_link_test_pattern)
1306 		link_hwss->ext.set_dp_link_test_pattern(link, link_res, &pattern_param);
1307 }
1308 
dp_set_hw_training_pattern(struct dc_link * link,const struct link_resource * link_res,enum dc_dp_training_pattern pattern,uint32_t offset)1309 bool dp_set_hw_training_pattern(
1310 	struct dc_link *link,
1311 	const struct link_resource *link_res,
1312 	enum dc_dp_training_pattern pattern,
1313 	uint32_t offset)
1314 {
1315 	enum dp_test_pattern test_pattern = DP_TEST_PATTERN_UNSUPPORTED;
1316 
1317 	switch (pattern) {
1318 	case DP_TRAINING_PATTERN_SEQUENCE_1:
1319 		test_pattern = DP_TEST_PATTERN_TRAINING_PATTERN1;
1320 		break;
1321 	case DP_TRAINING_PATTERN_SEQUENCE_2:
1322 		test_pattern = DP_TEST_PATTERN_TRAINING_PATTERN2;
1323 		break;
1324 	case DP_TRAINING_PATTERN_SEQUENCE_3:
1325 		test_pattern = DP_TEST_PATTERN_TRAINING_PATTERN3;
1326 		break;
1327 	case DP_TRAINING_PATTERN_SEQUENCE_4:
1328 		test_pattern = DP_TEST_PATTERN_TRAINING_PATTERN4;
1329 		break;
1330 	case DP_128b_132b_TPS1:
1331 		test_pattern = DP_TEST_PATTERN_128b_132b_TPS1_TRAINING_MODE;
1332 		break;
1333 	case DP_128b_132b_TPS2:
1334 		test_pattern = DP_TEST_PATTERN_128b_132b_TPS2_TRAINING_MODE;
1335 		break;
1336 	default:
1337 		break;
1338 	}
1339 
1340 	dp_set_hw_test_pattern(link, link_res, test_pattern, NULL, 0);
1341 
1342 	return true;
1343 }
1344 
perform_post_lt_adj_req_sequence(struct dc_link * link,const struct link_resource * link_res,struct link_training_settings * lt_settings)1345 static bool perform_post_lt_adj_req_sequence(
1346 		struct dc_link *link,
1347 		const struct link_resource *link_res,
1348 		struct link_training_settings *lt_settings)
1349 {
1350 	enum dc_lane_count lane_count =
1351 	lt_settings->link_settings.lane_count;
1352 
1353 	uint32_t adj_req_count;
1354 	uint32_t adj_req_timer;
1355 	bool req_drv_setting_changed;
1356 	uint32_t lane;
1357 	union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX] = {0};
1358 	union lane_align_status_updated dpcd_lane_status_updated = {0};
1359 	union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
1360 
1361 	req_drv_setting_changed = false;
1362 	for (adj_req_count = 0; adj_req_count < POST_LT_ADJ_REQ_LIMIT;
1363 	adj_req_count++) {
1364 
1365 		req_drv_setting_changed = false;
1366 
1367 		for (adj_req_timer = 0;
1368 			adj_req_timer < POST_LT_ADJ_REQ_TIMEOUT;
1369 			adj_req_timer++) {
1370 
1371 			dp_get_lane_status_and_lane_adjust(
1372 				link,
1373 				lt_settings,
1374 				dpcd_lane_status,
1375 				&dpcd_lane_status_updated,
1376 				dpcd_lane_adjust,
1377 				DPRX);
1378 
1379 			if (dpcd_lane_status_updated.bits.
1380 					POST_LT_ADJ_REQ_IN_PROGRESS == 0)
1381 				return true;
1382 
1383 			if (!dp_is_cr_done(lane_count, dpcd_lane_status))
1384 				return false;
1385 
1386 			if (!dp_is_ch_eq_done(lane_count, dpcd_lane_status) ||
1387 					!dp_is_symbol_locked(lane_count, dpcd_lane_status) ||
1388 					!dp_is_interlane_aligned(dpcd_lane_status_updated))
1389 				return false;
1390 
1391 			for (lane = 0; lane < (uint32_t)(lane_count); lane++) {
1392 
1393 				if (lt_settings->
1394 				dpcd_lane_settings[lane].bits.VOLTAGE_SWING_SET !=
1395 				dpcd_lane_adjust[lane].bits.VOLTAGE_SWING_LANE ||
1396 				lt_settings->dpcd_lane_settings[lane].bits.PRE_EMPHASIS_SET !=
1397 				dpcd_lane_adjust[lane].bits.PRE_EMPHASIS_LANE) {
1398 
1399 					req_drv_setting_changed = true;
1400 					break;
1401 				}
1402 			}
1403 
1404 			if (req_drv_setting_changed) {
1405 				dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
1406 						lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
1407 
1408 				dp_set_drive_settings(link,
1409 						link_res,
1410 						lt_settings);
1411 				break;
1412 			}
1413 
1414 			msleep(1);
1415 		}
1416 
1417 		if (!req_drv_setting_changed) {
1418 			DC_LOG_WARNING("%s: Post Link Training Adjust Request Timed out\n",
1419 				__func__);
1420 
1421 			ASSERT(0);
1422 			return true;
1423 		}
1424 	}
1425 	DC_LOG_WARNING("%s: Post Link Training Adjust Request limit reached\n",
1426 		__func__);
1427 
1428 	ASSERT(0);
1429 	return true;
1430 
1431 }
1432 
dp_transition_to_video_idle(struct dc_link * link,const struct link_resource * link_res,struct link_training_settings * lt_settings,enum link_training_result status)1433 static enum link_training_result dp_transition_to_video_idle(
1434 	struct dc_link *link,
1435 	const struct link_resource *link_res,
1436 	struct link_training_settings *lt_settings,
1437 	enum link_training_result status)
1438 {
1439 	union lane_count_set lane_count_set = {0};
1440 
1441 	/* 4. mainlink output idle pattern*/
1442 	dp_set_hw_test_pattern(link, link_res, DP_TEST_PATTERN_VIDEO_MODE, NULL, 0);
1443 
1444 	/*
1445 	 * 5. post training adjust if required
1446 	 * If the upstream DPTX and downstream DPRX both support TPS4,
1447 	 * TPS4 must be used instead of POST_LT_ADJ_REQ.
1448 	 */
1449 	if (link->dpcd_caps.max_ln_count.bits.POST_LT_ADJ_REQ_SUPPORTED != 1 ||
1450 			lt_settings->pattern_for_eq >= DP_TRAINING_PATTERN_SEQUENCE_4) {
1451 		/* delay 5ms after Main Link output idle pattern and then check
1452 		 * DPCD 0202h.
1453 		 */
1454 		if (link->connector_signal != SIGNAL_TYPE_EDP && status == LINK_TRAINING_SUCCESS) {
1455 			msleep(5);
1456 			status = dp_check_link_loss_status(link, lt_settings);
1457 		}
1458 		return status;
1459 	}
1460 
1461 	if (status == LINK_TRAINING_SUCCESS &&
1462 		perform_post_lt_adj_req_sequence(link, link_res, lt_settings) == false)
1463 		status = LINK_TRAINING_LQA_FAIL;
1464 
1465 	lane_count_set.bits.LANE_COUNT_SET = lt_settings->link_settings.lane_count;
1466 	lane_count_set.bits.ENHANCED_FRAMING = lt_settings->enhanced_framing;
1467 	lane_count_set.bits.POST_LT_ADJ_REQ_GRANTED = 0;
1468 
1469 	core_link_write_dpcd(
1470 		link,
1471 		DP_LANE_COUNT_SET,
1472 		&lane_count_set.raw,
1473 		sizeof(lane_count_set));
1474 
1475 	return status;
1476 }
1477 
dp_perform_link_training(struct dc_link * link,const struct link_resource * link_res,const struct dc_link_settings * link_settings,bool skip_video_pattern)1478 enum link_training_result dp_perform_link_training(
1479 	struct dc_link *link,
1480 	const struct link_resource *link_res,
1481 	const struct dc_link_settings *link_settings,
1482 	bool skip_video_pattern)
1483 {
1484 	enum link_training_result status = LINK_TRAINING_SUCCESS;
1485 	struct link_training_settings lt_settings = {0};
1486 	enum dp_link_encoding encoding =
1487 			link_dp_get_encoding_format(link_settings);
1488 
1489 	/* decide training settings */
1490 	dp_decide_training_settings(
1491 			link,
1492 			link_settings,
1493 			&lt_settings);
1494 
1495 	override_training_settings(
1496 			link,
1497 			&link->preferred_training_settings,
1498 			&lt_settings);
1499 
1500 	/* reset previous training states */
1501 	dpcd_exit_training_mode(link, encoding);
1502 
1503 	/* configure link prior to entering training mode */
1504 	dpcd_configure_lttpr_mode(link, &lt_settings);
1505 	dp_set_fec_ready(link, link_res, lt_settings.should_set_fec_ready);
1506 	dpcd_configure_channel_coding(link, &lt_settings);
1507 
1508 	/* enter training mode:
1509 	 * Per DP specs starting from here, DPTX device shall not issue
1510 	 * Non-LT AUX transactions inside training mode.
1511 	 */
1512 	if ((link->chip_caps & EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) && encoding == DP_8b_10b_ENCODING)
1513 		if (link->dc->config.use_old_fixed_vs_sequence)
1514 			status = dp_perform_fixed_vs_pe_training_sequence_legacy(link, link_res, &lt_settings);
1515 		else
1516 			status = dp_perform_fixed_vs_pe_training_sequence(link, link_res, &lt_settings);
1517 	else if (encoding == DP_8b_10b_ENCODING)
1518 		status = dp_perform_8b_10b_link_training(link, link_res, &lt_settings);
1519 	else if (encoding == DP_128b_132b_ENCODING)
1520 		status = dp_perform_128b_132b_link_training(link, link_res, &lt_settings);
1521 	else
1522 		ASSERT(0);
1523 
1524 	/* exit training mode */
1525 	dpcd_exit_training_mode(link, encoding);
1526 
1527 	/* switch to video idle */
1528 	if ((status == LINK_TRAINING_SUCCESS) || !skip_video_pattern)
1529 		status = dp_transition_to_video_idle(link,
1530 				link_res,
1531 				&lt_settings,
1532 				status);
1533 
1534 	/* dump debug data */
1535 	dp_log_training_result(link, &lt_settings, status);
1536 	if (status != LINK_TRAINING_SUCCESS)
1537 		link->ctx->dc->debug_data.ltFailCount++;
1538 	return status;
1539 }
1540 
perform_link_training_with_retries(const struct dc_link_settings * link_setting,bool skip_video_pattern,int attempts,struct pipe_ctx * pipe_ctx,enum signal_type signal,bool do_fallback)1541 bool perform_link_training_with_retries(
1542 	const struct dc_link_settings *link_setting,
1543 	bool skip_video_pattern,
1544 	int attempts,
1545 	struct pipe_ctx *pipe_ctx,
1546 	enum signal_type signal,
1547 	bool do_fallback)
1548 {
1549 	int j;
1550 	uint8_t delay_between_attempts = LINK_TRAINING_RETRY_DELAY;
1551 	struct dc_stream_state *stream = pipe_ctx->stream;
1552 	struct dc_link *link = stream->link;
1553 	enum dp_panel_mode panel_mode = dp_get_panel_mode(link);
1554 	enum link_training_result status = LINK_TRAINING_CR_FAIL_LANE0;
1555 	struct dc_link_settings cur_link_settings = *link_setting;
1556 	struct dc_link_settings max_link_settings = *link_setting;
1557 	const struct link_hwss *link_hwss = get_link_hwss(link, &pipe_ctx->link_res);
1558 	int fail_count = 0;
1559 	bool is_link_bw_low = false; /* link bandwidth < stream bandwidth */
1560 	bool is_link_bw_min = /* RBR x 1 */
1561 		(cur_link_settings.link_rate <= LINK_RATE_LOW) &&
1562 		(cur_link_settings.lane_count <= LANE_COUNT_ONE);
1563 
1564 	dp_trace_commit_lt_init(link);
1565 
1566 
1567 	if (link_dp_get_encoding_format(&cur_link_settings) == DP_8b_10b_ENCODING)
1568 		/* We need to do this before the link training to ensure the idle
1569 		 * pattern in SST mode will be sent right after the link training
1570 		 */
1571 		link_hwss->setup_stream_encoder(pipe_ctx);
1572 
1573 	dp_trace_set_lt_start_timestamp(link, false);
1574 	j = 0;
1575 	while (j < attempts && fail_count < (attempts * 10)) {
1576 
1577 		DC_LOG_HW_LINK_TRAINING("%s: Beginning link(%d) training attempt %u of %d @ rate(%d) x lane(%d) @ spread = %x\n",
1578 					__func__, link->link_index, (unsigned int)j + 1, attempts,
1579 				       cur_link_settings.link_rate, cur_link_settings.lane_count,
1580 				       cur_link_settings.link_spread);
1581 
1582 		dp_enable_link_phy(
1583 			link,
1584 			&pipe_ctx->link_res,
1585 			signal,
1586 			pipe_ctx->clock_source->id,
1587 			&cur_link_settings);
1588 
1589 		if (stream->sink_patches.dppowerup_delay > 0) {
1590 			int delay_dp_power_up_in_ms = stream->sink_patches.dppowerup_delay;
1591 
1592 			msleep(delay_dp_power_up_in_ms);
1593 		}
1594 
1595 		if (panel_mode == DP_PANEL_MODE_EDP) {
1596 			struct cp_psp *cp_psp = &stream->ctx->cp_psp;
1597 
1598 			if (cp_psp && cp_psp->funcs.enable_assr) {
1599 				/* ASSR is bound to fail with unsigned PSP
1600 				 * verstage used during devlopment phase.
1601 				 * Report and continue with eDP panel mode to
1602 				 * perform eDP link training with right settings
1603 				 */
1604 				bool result;
1605 				result = cp_psp->funcs.enable_assr(cp_psp->handle, link);
1606 				if (!result && link->panel_mode != DP_PANEL_MODE_EDP)
1607 					panel_mode = DP_PANEL_MODE_DEFAULT;
1608 			}
1609 		}
1610 
1611 		dp_set_panel_mode(link, panel_mode);
1612 
1613 		if (link->aux_access_disabled) {
1614 			dp_perform_link_training_skip_aux(link, &pipe_ctx->link_res, &cur_link_settings);
1615 			return true;
1616 		} else {
1617 			/** @todo Consolidate USB4 DP and DPx.x training. */
1618 			if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA) {
1619 				status = dpia_perform_link_training(
1620 						link,
1621 						&pipe_ctx->link_res,
1622 						&cur_link_settings,
1623 						skip_video_pattern);
1624 
1625 				/* Transmit idle pattern once training successful. */
1626 				if (status == LINK_TRAINING_SUCCESS && !is_link_bw_low) {
1627 					dp_set_hw_test_pattern(link, &pipe_ctx->link_res, DP_TEST_PATTERN_VIDEO_MODE, NULL, 0);
1628 					// Update verified link settings to current one
1629 					// Because DPIA LT might fallback to lower link setting.
1630 					if (stream->signal == SIGNAL_TYPE_DISPLAY_PORT_MST) {
1631 						link->verified_link_cap.link_rate = link->cur_link_settings.link_rate;
1632 						link->verified_link_cap.lane_count = link->cur_link_settings.lane_count;
1633 						dm_helpers_dp_mst_update_branch_bandwidth(link->ctx, link);
1634 					}
1635 				}
1636 			} else {
1637 				status = dp_perform_link_training(
1638 						link,
1639 						&pipe_ctx->link_res,
1640 						&cur_link_settings,
1641 						skip_video_pattern);
1642 			}
1643 
1644 			dp_trace_lt_total_count_increment(link, false);
1645 			dp_trace_lt_result_update(link, status, false);
1646 			dp_trace_set_lt_end_timestamp(link, false);
1647 			if (status == LINK_TRAINING_SUCCESS && !is_link_bw_low)
1648 				return true;
1649 		}
1650 
1651 		fail_count++;
1652 		dp_trace_lt_fail_count_update(link, fail_count, false);
1653 		if (link->ep_type == DISPLAY_ENDPOINT_PHY) {
1654 			/* latest link training still fail or link training is aborted
1655 			 * skip delay and keep PHY on
1656 			 */
1657 			if (j == (attempts - 1) || (status == LINK_TRAINING_ABORT))
1658 				break;
1659 		}
1660 
1661 		if (j == (attempts - 1)) {
1662 			DC_LOG_WARNING(
1663 				"%s: Link(%d) training attempt %u of %d failed @ rate(%d) x lane(%d) @ spread = %x : fail reason:(%d)\n",
1664 				__func__, link->link_index, (unsigned int)j + 1, attempts,
1665 				cur_link_settings.link_rate, cur_link_settings.lane_count,
1666 				cur_link_settings.link_spread, status);
1667 		} else {
1668 			DC_LOG_HW_LINK_TRAINING(
1669 				"%s: Link(%d) training attempt %u of %d failed @ rate(%d) x lane(%d) @ spread = %x : fail reason:(%d)\n",
1670 				__func__, link->link_index, (unsigned int)j + 1, attempts,
1671 				cur_link_settings.link_rate, cur_link_settings.lane_count,
1672 				cur_link_settings.link_spread, status);
1673 		}
1674 
1675 		dp_disable_link_phy(link, &pipe_ctx->link_res, signal);
1676 
1677 		/* Abort link training if failure due to sink being unplugged. */
1678 		if (status == LINK_TRAINING_ABORT) {
1679 			enum dc_connection_type type = dc_connection_none;
1680 
1681 			link_detect_connection_type(link, &type);
1682 			if (type == dc_connection_none) {
1683 				DC_LOG_HW_LINK_TRAINING("%s: Aborting training because sink unplugged\n", __func__);
1684 				break;
1685 			}
1686 		}
1687 
1688 		/* Try to train again at original settings if:
1689 		 * - not falling back between training attempts;
1690 		 * - aborted previous attempt due to reasons other than sink unplug;
1691 		 * - successfully trained but at a link rate lower than that required by stream;
1692 		 * - reached minimum link bandwidth.
1693 		 */
1694 		if (!do_fallback || (status == LINK_TRAINING_ABORT) ||
1695 				(status == LINK_TRAINING_SUCCESS && is_link_bw_low) ||
1696 				is_link_bw_min) {
1697 			j++;
1698 			cur_link_settings = *link_setting;
1699 			delay_between_attempts += LINK_TRAINING_RETRY_DELAY;
1700 			is_link_bw_low = false;
1701 			is_link_bw_min = (cur_link_settings.link_rate <= LINK_RATE_LOW) &&
1702 				(cur_link_settings.lane_count <= LANE_COUNT_ONE);
1703 
1704 		} else if (do_fallback) { /* Try training at lower link bandwidth if doing fallback. */
1705 			uint32_t req_bw;
1706 			uint32_t link_bw;
1707 			enum dc_link_encoding_format link_encoding = DC_LINK_ENCODING_UNSPECIFIED;
1708 
1709 			decide_fallback_link_setting(link, &max_link_settings,
1710 					&cur_link_settings, status);
1711 
1712 			if (link_dp_get_encoding_format(&cur_link_settings) == DP_8b_10b_ENCODING)
1713 				link_encoding = DC_LINK_ENCODING_DP_8b_10b;
1714 			else if (link_dp_get_encoding_format(&cur_link_settings) == DP_128b_132b_ENCODING)
1715 				link_encoding = DC_LINK_ENCODING_DP_128b_132b;
1716 
1717 			/* Flag if reduced link bandwidth no longer meets stream requirements or fallen back to
1718 			 * minimum link bandwidth.
1719 			 */
1720 			req_bw = dc_bandwidth_in_kbps_from_timing(&stream->timing, link_encoding);
1721 			link_bw = dp_link_bandwidth_kbps(link, &cur_link_settings);
1722 			is_link_bw_low = (req_bw > link_bw);
1723 			is_link_bw_min = ((cur_link_settings.link_rate <= LINK_RATE_LOW) &&
1724 				(cur_link_settings.lane_count <= LANE_COUNT_ONE));
1725 
1726 			if (is_link_bw_low)
1727 				DC_LOG_WARNING(
1728 					"%s: Link(%d) bandwidth too low after fallback req_bw(%d) > link_bw(%d)\n",
1729 					__func__, link->link_index, req_bw, link_bw);
1730 		}
1731 
1732 		msleep(delay_between_attempts);
1733 	}
1734 
1735 	return false;
1736 }
1737 
1738