xref: /linux/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c (revision 92c4c9fdc838d3b41a996bb700ea64b9e78fc7ea)
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 dp specific link capability retrieval sequence. It is
28  * responsible for retrieving, parsing, overriding, deciding capability obtained
29  * from dp link. Link capability consists of encoders, DPRXs, cables, retimers,
30  * usb and all other possible backend capabilities. Other components should
31  * include this header file in order to access link capability. Accessing link
32  * capability by dereferencing dc_link outside dp_link_capability is not a
33  * recommended method as it makes the component dependent on the underlying data
34  * structure used to represent link capability instead of function interfaces.
35  */
36 
37 #include "link_dp_capability.h"
38 #include "link_ddc.h"
39 #include "link_dpcd.h"
40 #include "link_dp_dpia.h"
41 #include "link_dp_phy.h"
42 #include "link_edp_panel_control.h"
43 #include "link_dp_irq_handler.h"
44 #include "link/accessories/link_dp_trace.h"
45 #include "link/link_detection.h"
46 #include "link/link_validation.h"
47 #include "link_dp_training.h"
48 #include "atomfirmware.h"
49 #include "resource.h"
50 #include "link_enc_cfg.h"
51 #include "dc_dmub_srv.h"
52 #include "gpio_service_interface.h"
53 
54 #define DC_TRACE_LEVEL_MESSAGE(...) /* do nothing */
55 
56 #define DC_LOGGER \
57 	link->ctx->logger
58 
59 #ifndef MAX
60 #define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
61 #endif
62 #ifndef MIN
63 #define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
64 #endif
65 
66 struct dp_lt_fallback_entry {
67 	enum dc_lane_count lane_count;
68 	enum dc_link_rate link_rate;
69 };
70 
71 static const struct dp_lt_fallback_entry dp_lt_fallbacks[] = {
72 		/* This link training fallback array is ordered by
73 		 * link bandwidth from highest to lowest.
74 		 * DP specs makes it a normative policy to always
75 		 * choose the next highest link bandwidth during
76 		 * link training fallback.
77 		 */
78 		{LANE_COUNT_FOUR, LINK_RATE_UHBR20},
79 		{LANE_COUNT_FOUR, LINK_RATE_UHBR13_5},
80 		{LANE_COUNT_TWO, LINK_RATE_UHBR20},
81 		{LANE_COUNT_FOUR, LINK_RATE_UHBR10},
82 		{LANE_COUNT_TWO, LINK_RATE_UHBR13_5},
83 		{LANE_COUNT_FOUR, LINK_RATE_HIGH3},
84 		{LANE_COUNT_ONE, LINK_RATE_UHBR20},
85 		{LANE_COUNT_TWO, LINK_RATE_UHBR10},
86 		{LANE_COUNT_FOUR, LINK_RATE_HIGH2},
87 		{LANE_COUNT_ONE, LINK_RATE_UHBR13_5},
88 		{LANE_COUNT_TWO, LINK_RATE_HIGH3},
89 		{LANE_COUNT_ONE, LINK_RATE_UHBR10},
90 		{LANE_COUNT_TWO, LINK_RATE_HIGH2},
91 		{LANE_COUNT_FOUR, LINK_RATE_HIGH},
92 		{LANE_COUNT_ONE, LINK_RATE_HIGH3},
93 		{LANE_COUNT_FOUR, LINK_RATE_LOW},
94 		{LANE_COUNT_ONE, LINK_RATE_HIGH2},
95 		{LANE_COUNT_TWO, LINK_RATE_HIGH},
96 		{LANE_COUNT_TWO, LINK_RATE_LOW},
97 		{LANE_COUNT_ONE, LINK_RATE_HIGH},
98 		{LANE_COUNT_ONE, LINK_RATE_LOW},
99 };
100 
101 static const struct dc_link_settings fail_safe_link_settings = {
102 		.lane_count = LANE_COUNT_ONE,
103 		.link_rate = LINK_RATE_LOW,
104 		.link_spread = LINK_SPREAD_DISABLED,
105 };
106 
is_dp_active_dongle(const struct dc_link * link)107 bool is_dp_active_dongle(const struct dc_link *link)
108 {
109 	return (link->dpcd_caps.dongle_type >= DISPLAY_DONGLE_DP_VGA_CONVERTER) &&
110 				(link->dpcd_caps.dongle_type <= DISPLAY_DONGLE_DP_HDMI_CONVERTER);
111 }
112 
is_dp_branch_device(const struct dc_link * link)113 bool is_dp_branch_device(const struct dc_link *link)
114 {
115 	return link->dpcd_caps.is_branch_dev;
116 }
117 
translate_dpcd_max_bpc(enum dpcd_downstream_port_max_bpc bpc)118 static int translate_dpcd_max_bpc(enum dpcd_downstream_port_max_bpc bpc)
119 {
120 	switch (bpc) {
121 	case DOWN_STREAM_MAX_8BPC:
122 		return 8;
123 	case DOWN_STREAM_MAX_10BPC:
124 		return 10;
125 	case DOWN_STREAM_MAX_12BPC:
126 		return 12;
127 	case DOWN_STREAM_MAX_16BPC:
128 		return 16;
129 	default:
130 		break;
131 	}
132 
133 	return -1;
134 }
135 
dp_parse_lttpr_repeater_count(uint8_t lttpr_repeater_count)136 uint8_t dp_parse_lttpr_repeater_count(uint8_t lttpr_repeater_count)
137 {
138 	switch (lttpr_repeater_count) {
139 	case 0x80: // 1 lttpr repeater
140 		return 1;
141 	case 0x40: // 2 lttpr repeaters
142 		return 2;
143 	case 0x20: // 3 lttpr repeaters
144 		return 3;
145 	case 0x10: // 4 lttpr repeaters
146 		return 4;
147 	case 0x08: // 5 lttpr repeaters
148 		return 5;
149 	case 0x04: // 6 lttpr repeaters
150 		return 6;
151 	case 0x02: // 7 lttpr repeaters
152 		return 7;
153 	case 0x01: // 8 lttpr repeaters
154 		return 8;
155 	default:
156 		break;
157 	}
158 	return 0; // invalid value
159 }
160 
dp_get_closest_lttpr_offset(uint8_t lttpr_count)161 uint32_t dp_get_closest_lttpr_offset(uint8_t lttpr_count)
162 {
163 	/* Calculate offset for LTTPR closest to DPTX which is highest in the chain
164 	 * Offset is 0 for single LTTPR cases as base LTTPR DPCD addresses target LTTPR 1
165 	 */
166 	return DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE * (lttpr_count - 1);
167 }
168 
link_bw_kbps_from_raw_frl_link_rate_data(uint8_t bw)169 uint32_t link_bw_kbps_from_raw_frl_link_rate_data(uint8_t bw)
170 {
171 	switch (bw) {
172 	case 0b001:
173 		return 9000000;
174 	case 0b010:
175 		return 18000000;
176 	case 0b011:
177 		return 24000000;
178 	case 0b100:
179 		return 32000000;
180 	case 0b101:
181 		return 40000000;
182 	case 0b110:
183 		return 48000000;
184 	}
185 
186 	return 0;
187 }
188 
linkRateInKHzToLinkRateMultiplier(uint32_t link_rate_in_khz)189 static enum dc_link_rate linkRateInKHzToLinkRateMultiplier(uint32_t link_rate_in_khz)
190 {
191 	enum dc_link_rate link_rate;
192 	// LinkRate is normally stored as a multiplier of 0.27 Gbps per lane. Do the translation.
193 	switch (link_rate_in_khz) {
194 	case 1620000:
195 		link_rate = LINK_RATE_LOW;	// Rate_1 (RBR)	- 1.62 Gbps/Lane
196 		break;
197 	case 2160000:
198 		link_rate = LINK_RATE_RATE_2;	// Rate_2	- 2.16 Gbps/Lane
199 		break;
200 	case 2430000:
201 		link_rate = LINK_RATE_RATE_3;	// Rate_3	- 2.43 Gbps/Lane
202 		break;
203 	case 2700000:
204 		link_rate = LINK_RATE_HIGH;	// Rate_4 (HBR)	- 2.70 Gbps/Lane
205 		break;
206 	case 3240000:
207 		link_rate = LINK_RATE_RBR2;	// Rate_5 (RBR2)- 3.24 Gbps/Lane
208 		break;
209 	case 4320000:
210 		link_rate = LINK_RATE_RATE_6;	// Rate_6	- 4.32 Gbps/Lane
211 		break;
212 	case 5400000:
213 		link_rate = LINK_RATE_HIGH2;	// Rate_7 (HBR2)- 5.40 Gbps/Lane
214 		break;
215 	case 6750000:
216 		link_rate = LINK_RATE_RATE_8;	// Rate_8	- 6.75 Gbps/Lane
217 		break;
218 	case 8100000:
219 		link_rate = LINK_RATE_HIGH3;	// Rate_9 (HBR3)- 8.10 Gbps/Lane
220 		break;
221 	case 10000000:
222 		link_rate = LINK_RATE_UHBR10;	// UHBR10 - 10.0 Gbps/Lane
223 		break;
224 	case 13500000:
225 		link_rate = LINK_RATE_UHBR13_5;	// UHBR13.5 - 13.5 Gbps/Lane
226 		break;
227 	case 20000000:
228 		link_rate = LINK_RATE_UHBR20;	// UHBR20 - 20.0 Gbps/Lane
229 		break;
230 
231 	default:
232 		link_rate = LINK_RATE_UNKNOWN;
233 		break;
234 	}
235 	return link_rate;
236 }
237 
intersect_cable_id(union dp_cable_id * a,union dp_cable_id * b)238 static union dp_cable_id intersect_cable_id(
239 		union dp_cable_id *a, union dp_cable_id *b)
240 {
241 	union dp_cable_id out;
242 
243 	out.bits.UHBR10_20_CAPABILITY = MIN(a->bits.UHBR10_20_CAPABILITY,
244 			b->bits.UHBR10_20_CAPABILITY);
245 	out.bits.UHBR13_5_CAPABILITY = MIN(a->bits.UHBR13_5_CAPABILITY,
246 			b->bits.UHBR13_5_CAPABILITY);
247 	out.bits.CABLE_TYPE = MAX(a->bits.CABLE_TYPE, b->bits.CABLE_TYPE);
248 
249 	return out;
250 }
251 
252 /*
253  * Return PCON's post FRL link training supported BW if its non-zero, otherwise return max_supported_frl_bw.
254  */
intersect_frl_link_bw_support(const uint32_t max_supported_frl_bw_in_kbps,const union hdmi_encoded_link_bw hdmi_encoded_link_bw)255 static uint32_t intersect_frl_link_bw_support(
256 	const uint32_t max_supported_frl_bw_in_kbps,
257 	const union hdmi_encoded_link_bw hdmi_encoded_link_bw)
258 {
259 	uint32_t supported_bw_in_kbps = max_supported_frl_bw_in_kbps;
260 
261 	/* Skip checking FRL_MODE bit, as certain PCON will clear
262 	 * it despite supporting the link BW indicated in the other bits.
263 	 */
264 	if (hdmi_encoded_link_bw.bits.BW_48Gbps)
265 		supported_bw_in_kbps = 48000000;
266 	else if (hdmi_encoded_link_bw.bits.BW_40Gbps)
267 		supported_bw_in_kbps = 40000000;
268 	else if (hdmi_encoded_link_bw.bits.BW_32Gbps)
269 		supported_bw_in_kbps = 32000000;
270 	else if (hdmi_encoded_link_bw.bits.BW_24Gbps)
271 		supported_bw_in_kbps = 24000000;
272 	else if (hdmi_encoded_link_bw.bits.BW_18Gbps)
273 		supported_bw_in_kbps = 18000000;
274 	else if (hdmi_encoded_link_bw.bits.BW_9Gbps)
275 		supported_bw_in_kbps = 9000000;
276 	else if (hdmi_encoded_link_bw.bits.FRL_LINK_TRAINING_FINISHED)
277 		supported_bw_in_kbps = 0; /* This case should only get hit in regulated autonomous mode. */
278 
279 	return supported_bw_in_kbps;
280 }
281 
get_clock_source_id(struct dc_link * link)282 static enum clock_source_id get_clock_source_id(struct dc_link *link)
283 {
284 	enum clock_source_id dp_cs_id = CLOCK_SOURCE_ID_UNDEFINED;
285 	struct clock_source *dp_cs = link->dc->res_pool->dp_clock_source;
286 
287 	if (dp_cs != NULL) {
288 		dp_cs_id = dp_cs->id;
289 	} else {
290 		/*
291 		 * dp clock source is not initialized for some reason.
292 		 * Should not happen, CLOCK_SOURCE_ID_EXTERNAL will be used
293 		 */
294 		ASSERT(dp_cs);
295 	}
296 
297 	return dp_cs_id;
298 }
299 
dp_wa_power_up_0010FA(struct dc_link * link,uint8_t * dpcd_data,int length)300 static void dp_wa_power_up_0010FA(struct dc_link *link, uint8_t *dpcd_data,
301 		int length)
302 {
303 	int retry = 0;
304 
305 	if (!link->dpcd_caps.dpcd_rev.raw) {
306 		do {
307 			dpcd_write_rx_power_ctrl(link, true);
308 			core_link_read_dpcd(link, DP_DPCD_REV,
309 							dpcd_data, length);
310 			link->dpcd_caps.dpcd_rev.raw = dpcd_data[
311 				DP_DPCD_REV -
312 				DP_DPCD_REV];
313 		} while (retry++ < 4 && !link->dpcd_caps.dpcd_rev.raw);
314 	}
315 
316 	if (link->dpcd_caps.dongle_type == DISPLAY_DONGLE_DP_VGA_CONVERTER) {
317 		switch (link->dpcd_caps.branch_dev_id) {
318 		/* 0010FA active dongles (DP-VGA, DP-DLDVI converters) power down
319 		 * all internal circuits including AUX communication preventing
320 		 * reading DPCD table and EDID (spec violation).
321 		 * Encoder will skip DP RX power down on disable_output to
322 		 * keep receiver powered all the time.*/
323 		case DP_BRANCH_DEVICE_ID_0010FA:
324 		case DP_BRANCH_DEVICE_ID_0080E1:
325 		case DP_BRANCH_DEVICE_ID_00E04C:
326 			link->wa_flags.dp_keep_receiver_powered = true;
327 			break;
328 
329 		/* TODO: May need work around for other dongles. */
330 		default:
331 			link->wa_flags.dp_keep_receiver_powered = false;
332 			break;
333 		}
334 	} else
335 		link->wa_flags.dp_keep_receiver_powered = false;
336 }
337 
dp_is_fec_supported(const struct dc_link * link)338 bool dp_is_fec_supported(const struct dc_link *link)
339 {
340 	/* TODO - use asic cap instead of link_enc->features
341 	 * we no longer know which link enc to use for this link before commit
342 	 */
343 	struct resource_context *res_ctx = &link->dc->current_state->res_ctx;
344 	struct resource_pool *res_pool = link->dc->res_pool;
345 	struct link_encoder *link_enc = get_temp_dio_link_enc(res_ctx, res_pool, link);
346 
347 	if (!link->dc->config.unify_link_enc_assignment)
348 		link_enc = link_enc_cfg_get_link_enc(link);
349 	ASSERT(link_enc);
350 
351 	return (dc_is_dp_signal(link->connector_signal) && link_enc &&
352 			link_enc->features.fec_supported &&
353 			link->dpcd_caps.fec_cap.bits.FEC_CAPABLE);
354 }
355 
dp_should_enable_fec(const struct dc_link * link)356 bool dp_should_enable_fec(const struct dc_link *link)
357 {
358 	bool force_disable = false;
359 
360 	if (link->dc->debug.disable_fec)
361 		force_disable = true;
362 	else if (link->fec_state == dc_link_fec_enabled)
363 		force_disable = false;
364 	else if (link->connector_signal != SIGNAL_TYPE_DISPLAY_PORT_MST &&
365 			link->local_sink &&
366 			link->local_sink->edid_caps.panel_patch.disable_fec)
367 		force_disable = true;
368 	else if (link->connector_signal == SIGNAL_TYPE_EDP
369 			&& (link->dpcd_caps.dsc_caps.dsc_basic_caps.fields.
370 			 dsc_support.DSC_SUPPORT == false
371 				|| link->panel_config.dsc.disable_dsc_edp
372 				|| !link->dc->caps.edp_dsc_support))
373 		force_disable = true;
374 
375 	return !force_disable && dp_is_fec_supported(link);
376 }
377 
dp_is_128b_132b_signal(struct pipe_ctx * pipe_ctx)378 bool dp_is_128b_132b_signal(struct pipe_ctx *pipe_ctx)
379 {
380 	/* If this assert is hit then we have a link encoder dynamic management issue */
381 	ASSERT(pipe_ctx->stream_res.hpo_dp_stream_enc ? pipe_ctx->link_res.hpo_dp_link_enc != NULL : true);
382 	return (pipe_ctx->stream_res.hpo_dp_stream_enc &&
383 			pipe_ctx->link_res.hpo_dp_link_enc &&
384 			dc_is_dp_signal(pipe_ctx->stream->signal));
385 }
386 
dp_is_lttpr_present(struct dc_link * link)387 bool dp_is_lttpr_present(struct dc_link *link)
388 {
389 	/* Some sink devices report invalid LTTPR revision, so don't validate against that cap */
390 	uint32_t lttpr_count = dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
391 	bool is_lttpr_present = (lttpr_count > 0 &&
392 			link->dpcd_caps.lttpr_caps.max_lane_count > 0 &&
393 			link->dpcd_caps.lttpr_caps.max_lane_count <= 4);
394 
395 	if (lttpr_count > 0 && !is_lttpr_present)
396 		DC_LOG_ERROR("LTTPR count is nonzero but invalid lane count reported. Assuming no LTTPR present.\n");
397 
398 	return is_lttpr_present;
399 }
400 
401 /* in DP compliance test, DPR-120 may have
402  * a random value in its MAX_LINK_BW dpcd field.
403  * We map it to the maximum supported link rate that
404  * is smaller than MAX_LINK_BW in this case.
405  */
get_link_rate_from_max_link_bw(uint8_t max_link_bw)406 static enum dc_link_rate get_link_rate_from_max_link_bw(
407 		 uint8_t max_link_bw)
408 {
409 	enum dc_link_rate link_rate;
410 
411 	if (max_link_bw >= LINK_RATE_HIGH3) {
412 		link_rate = LINK_RATE_HIGH3;
413 	} else if (max_link_bw < LINK_RATE_HIGH3
414 			&& max_link_bw >= LINK_RATE_HIGH2) {
415 		link_rate = LINK_RATE_HIGH2;
416 	} else if (max_link_bw < LINK_RATE_HIGH2
417 			&& max_link_bw >= LINK_RATE_HIGH) {
418 		link_rate = LINK_RATE_HIGH;
419 	} else if (max_link_bw < LINK_RATE_HIGH
420 			&& max_link_bw >= LINK_RATE_LOW) {
421 		link_rate = LINK_RATE_LOW;
422 	} else {
423 		link_rate = LINK_RATE_UNKNOWN;
424 	}
425 
426 	return link_rate;
427 }
428 
get_lttpr_max_lane_count(struct dc_link * link)429 static enum dc_lane_count get_lttpr_max_lane_count(struct dc_link *link)
430 {
431 	enum dc_lane_count lttpr_max_lane_count = LANE_COUNT_UNKNOWN;
432 
433 	if (link->dpcd_caps.lttpr_caps.max_lane_count <= LANE_COUNT_DP_MAX)
434 		lttpr_max_lane_count = link->dpcd_caps.lttpr_caps.max_lane_count;
435 
436 	/* if bw_allocation is enabled and nrd_max_lane_count is set, use it */
437 	if (link->dpia_bw_alloc_config.bw_alloc_enabled &&
438 			link->dpia_bw_alloc_config.nrd_max_lane_count > 0)
439 		lttpr_max_lane_count = link->dpia_bw_alloc_config.nrd_max_lane_count;
440 
441 	return lttpr_max_lane_count;
442 }
443 
get_lttpr_max_link_rate(struct dc_link * link)444 static enum dc_link_rate get_lttpr_max_link_rate(struct dc_link *link)
445 {
446 
447 	enum dc_link_rate lttpr_max_link_rate = LINK_RATE_UNKNOWN;
448 
449 	switch (link->dpcd_caps.lttpr_caps.max_link_rate) {
450 	case LINK_RATE_LOW:
451 	case LINK_RATE_HIGH:
452 	case LINK_RATE_HIGH2:
453 	case LINK_RATE_HIGH3:
454 		lttpr_max_link_rate = link->dpcd_caps.lttpr_caps.max_link_rate;
455 		break;
456 	}
457 
458 	/* if bw_allocation is enabled and nrd_max_link_rate is set, use it */
459 	if (link->dpia_bw_alloc_config.bw_alloc_enabled &&
460 			link->dpia_bw_alloc_config.nrd_max_link_rate > 0)
461 		lttpr_max_link_rate = link->dpia_bw_alloc_config.nrd_max_link_rate;
462 
463 	if (link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.bits.UHBR20)
464 		lttpr_max_link_rate = LINK_RATE_UHBR20;
465 	else if (link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.bits.UHBR13_5)
466 		lttpr_max_link_rate = LINK_RATE_UHBR13_5;
467 	else if (link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.bits.UHBR10)
468 		lttpr_max_link_rate = LINK_RATE_UHBR10;
469 
470 	return lttpr_max_link_rate;
471 }
472 
get_cable_max_link_rate(struct dc_link * link)473 static enum dc_link_rate get_cable_max_link_rate(struct dc_link *link)
474 {
475 	enum dc_link_rate cable_max_link_rate = LINK_RATE_UNKNOWN;
476 
477 	if (link->dpcd_caps.cable_id.bits.UHBR10_20_CAPABILITY & DP_UHBR20) {
478 		cable_max_link_rate = LINK_RATE_UHBR20;
479 	} else if (link->dpcd_caps.cable_id.bits.UHBR13_5_CAPABILITY) {
480 		cable_max_link_rate = LINK_RATE_UHBR13_5;
481 	} else if (link->dpcd_caps.cable_id.bits.UHBR10_20_CAPABILITY & DP_UHBR10) {
482 		// allow DP40 cables to do UHBR13.5 for passive or unknown cable type
483 		if (link->dpcd_caps.cable_id.bits.CABLE_TYPE < 2) {
484 			cable_max_link_rate = LINK_RATE_UHBR13_5;
485 		} else {
486 			cable_max_link_rate = LINK_RATE_UHBR10;
487 		}
488 	}
489 
490 	return cable_max_link_rate;
491 }
492 
reached_minimum_lane_count(enum dc_lane_count lane_count)493 static inline bool reached_minimum_lane_count(enum dc_lane_count lane_count)
494 {
495 	return lane_count <= LANE_COUNT_ONE;
496 }
497 
reached_minimum_link_rate(enum dc_link_rate link_rate)498 static inline bool reached_minimum_link_rate(enum dc_link_rate link_rate)
499 {
500 	return link_rate <= LINK_RATE_LOW;
501 }
502 
reduce_lane_count(enum dc_lane_count lane_count)503 static enum dc_lane_count reduce_lane_count(enum dc_lane_count lane_count)
504 {
505 	switch (lane_count) {
506 	case LANE_COUNT_FOUR:
507 		return LANE_COUNT_TWO;
508 	case LANE_COUNT_TWO:
509 		return LANE_COUNT_ONE;
510 	case LANE_COUNT_ONE:
511 		return LANE_COUNT_UNKNOWN;
512 	default:
513 		return LANE_COUNT_UNKNOWN;
514 	}
515 }
516 
reduce_link_rate(const struct dc_link * link,enum dc_link_rate link_rate)517 static enum dc_link_rate reduce_link_rate(const struct dc_link *link, enum dc_link_rate link_rate)
518 {
519 	// NEEDSWORK: provide some details about why this function never returns some of the
520 	// obscure link rates such as 4.32 Gbps or 3.24 Gbps and if such behavior is intended.
521 	//
522 
523 	switch (link_rate) {
524 	case LINK_RATE_UHBR20:
525 		return LINK_RATE_UHBR13_5;
526 	case LINK_RATE_UHBR13_5:
527 		return LINK_RATE_UHBR10;
528 	case LINK_RATE_UHBR10:
529 		return LINK_RATE_HIGH3;
530 	case LINK_RATE_HIGH3:
531 		if (link->connector_signal == SIGNAL_TYPE_EDP && link->dc->debug.support_eDP1_5)
532 			return LINK_RATE_RATE_8;
533 		return LINK_RATE_HIGH2;
534 	case LINK_RATE_RATE_8:
535 		return LINK_RATE_HIGH2;
536 	case LINK_RATE_HIGH2:
537 		return LINK_RATE_HIGH;
538 	case LINK_RATE_RATE_6:
539 	case LINK_RATE_RBR2:
540 		return LINK_RATE_HIGH;
541 	case LINK_RATE_HIGH:
542 		return LINK_RATE_LOW;
543 	case LINK_RATE_RATE_3:
544 	case LINK_RATE_RATE_2:
545 		return LINK_RATE_LOW;
546 	case LINK_RATE_LOW:
547 	default:
548 		return LINK_RATE_UNKNOWN;
549 	}
550 }
551 
increase_lane_count(enum dc_lane_count lane_count)552 static enum dc_lane_count increase_lane_count(enum dc_lane_count lane_count)
553 {
554 	switch (lane_count) {
555 	case LANE_COUNT_ONE:
556 		return LANE_COUNT_TWO;
557 	case LANE_COUNT_TWO:
558 		return LANE_COUNT_FOUR;
559 	default:
560 		return LANE_COUNT_UNKNOWN;
561 	}
562 }
563 
increase_link_rate(struct dc_link * link,enum dc_link_rate link_rate)564 static enum dc_link_rate increase_link_rate(struct dc_link *link,
565 		enum dc_link_rate link_rate)
566 {
567 	switch (link_rate) {
568 	case LINK_RATE_LOW:
569 		return LINK_RATE_HIGH;
570 	case LINK_RATE_HIGH:
571 		return LINK_RATE_HIGH2;
572 	case LINK_RATE_HIGH2:
573 		return LINK_RATE_HIGH3;
574 	case LINK_RATE_HIGH3:
575 		return LINK_RATE_UHBR10;
576 	case LINK_RATE_UHBR10:
577 		/* upto DP2.x specs UHBR13.5 is the only link rate that could be
578 		 * not supported by DPRX when higher link rate is supported.
579 		 * so we treat it as a special case for code simplicity. When we
580 		 * have new specs with more link rates like this, we should
581 		 * consider a more generic solution to handle discrete link
582 		 * rate capabilities.
583 		 */
584 		return link->dpcd_caps.dp_128b_132b_supported_link_rates.bits.UHBR13_5 ?
585 				LINK_RATE_UHBR13_5 : LINK_RATE_UHBR20;
586 	case LINK_RATE_UHBR13_5:
587 		return LINK_RATE_UHBR20;
588 	default:
589 		return LINK_RATE_UNKNOWN;
590 	}
591 }
592 
increase_edp_link_rate(struct dc_link * link,struct dc_link_settings * current_link_setting)593 static void increase_edp_link_rate(struct dc_link *link,
594 		struct dc_link_settings *current_link_setting)
595 {
596 	if (current_link_setting->use_link_rate_set) {
597 		if (current_link_setting->link_rate_set < link->dpcd_caps.edp_supported_link_rates_count) {
598 			current_link_setting->link_rate_set++;
599 			current_link_setting->link_rate =
600 				link->dpcd_caps.edp_supported_link_rates[current_link_setting->link_rate_set];
601 		} else {
602 			current_link_setting->use_link_rate_set = false;
603 			current_link_setting->link_rate = LINK_RATE_UHBR10;
604 		}
605 	} else {
606 		current_link_setting->link_rate = increase_link_rate(link, current_link_setting->link_rate);
607 	}
608 }
609 
decide_fallback_link_setting_max_bw_policy(struct dc_link * link,const struct dc_link_settings * max,struct dc_link_settings * cur,enum link_training_result training_result)610 static bool decide_fallback_link_setting_max_bw_policy(
611 		struct dc_link *link,
612 		const struct dc_link_settings *max,
613 		struct dc_link_settings *cur,
614 		enum link_training_result training_result)
615 {
616 	uint32_t cur_idx = 0, next_idx;
617 	bool found = false;
618 
619 	if (training_result == LINK_TRAINING_ABORT)
620 		return false;
621 
622 	while (cur_idx < ARRAY_SIZE(dp_lt_fallbacks))
623 		/* find current index */
624 		if (dp_lt_fallbacks[cur_idx].lane_count == cur->lane_count &&
625 				dp_lt_fallbacks[cur_idx].link_rate == cur->link_rate)
626 			break;
627 		else
628 			cur_idx++;
629 
630 	next_idx = cur_idx + 1;
631 
632 	while (next_idx < ARRAY_SIZE(dp_lt_fallbacks))
633 		/* find next index */
634 		if (dp_lt_fallbacks[next_idx].lane_count > max->lane_count ||
635 				dp_lt_fallbacks[next_idx].link_rate > max->link_rate)
636 			next_idx++;
637 		else if (dp_lt_fallbacks[next_idx].link_rate == LINK_RATE_UHBR13_5 &&
638 				link->dpcd_caps.dp_128b_132b_supported_link_rates.bits.UHBR13_5 == 0)
639 			/* upto DP2.x specs UHBR13.5 is the only link rate that
640 			 * could be not supported by DPRX when higher link rate
641 			 * is supported. so we treat it as a special case for
642 			 * code simplicity. When we have new specs with more
643 			 * link rates like this, we should consider a more
644 			 * generic solution to handle discrete link rate
645 			 * capabilities.
646 			 */
647 			next_idx++;
648 		else
649 			break;
650 
651 	if (next_idx < ARRAY_SIZE(dp_lt_fallbacks)) {
652 		cur->lane_count = dp_lt_fallbacks[next_idx].lane_count;
653 		cur->link_rate = dp_lt_fallbacks[next_idx].link_rate;
654 		found = true;
655 	}
656 
657 	return found;
658 }
659 
660 /*
661  * function: set link rate and lane count fallback based
662  * on current link setting and last link training result
663  * return value:
664  *			true - link setting could be set
665  *			false - has reached minimum setting
666  *					and no further fallback could be done
667  */
decide_fallback_link_setting(struct dc_link * link,struct dc_link_settings * max,struct dc_link_settings * cur,enum link_training_result training_result)668 bool decide_fallback_link_setting(
669 		struct dc_link *link,
670 		struct dc_link_settings *max,
671 		struct dc_link_settings *cur,
672 		enum link_training_result training_result)
673 {
674 	if (link_dp_get_encoding_format(max) == DP_128b_132b_ENCODING ||
675 			link->dc->debug.force_dp2_lt_fallback_method)
676 		return decide_fallback_link_setting_max_bw_policy(link, max,
677 				cur, training_result);
678 
679 	switch (training_result) {
680 	case LINK_TRAINING_CR_FAIL_LANE0:
681 	case LINK_TRAINING_CR_FAIL_LANE1:
682 	case LINK_TRAINING_CR_FAIL_LANE23:
683 	case LINK_TRAINING_LQA_FAIL:
684 	{
685 		if (!reached_minimum_link_rate(cur->link_rate)) {
686 			cur->link_rate = reduce_link_rate(link, cur->link_rate);
687 		} else if (!reached_minimum_lane_count(cur->lane_count)) {
688 			cur->link_rate = max->link_rate;
689 			if (training_result == LINK_TRAINING_CR_FAIL_LANE0)
690 				return false;
691 			else if (training_result == LINK_TRAINING_CR_FAIL_LANE1)
692 				cur->lane_count = LANE_COUNT_ONE;
693 			else if (training_result == LINK_TRAINING_CR_FAIL_LANE23)
694 				cur->lane_count = LANE_COUNT_TWO;
695 			else
696 				cur->lane_count = reduce_lane_count(cur->lane_count);
697 		} else {
698 			return false;
699 		}
700 		break;
701 	}
702 	case LINK_TRAINING_EQ_FAIL_EQ:
703 	case LINK_TRAINING_EQ_FAIL_CR_PARTIAL:
704 	{
705 		if (!reached_minimum_lane_count(cur->lane_count)) {
706 			cur->lane_count = reduce_lane_count(cur->lane_count);
707 		} else if (!reached_minimum_link_rate(cur->link_rate)) {
708 			cur->link_rate = reduce_link_rate(link, cur->link_rate);
709 			/* Reduce max link rate to avoid potential infinite loop.
710 			 * Needed so that any subsequent CR_FAIL fallback can't
711 			 * re-set the link rate higher than the link rate from
712 			 * the latest EQ_FAIL fallback.
713 			 */
714 			max->link_rate = cur->link_rate;
715 			cur->lane_count = max->lane_count;
716 		} else {
717 			return false;
718 		}
719 		break;
720 	}
721 	case LINK_TRAINING_EQ_FAIL_CR:
722 	{
723 		if (!reached_minimum_link_rate(cur->link_rate)) {
724 			cur->link_rate = reduce_link_rate(link, cur->link_rate);
725 			/* Reduce max link rate to avoid potential infinite loop.
726 			 * Needed so that any subsequent CR_FAIL fallback can't
727 			 * re-set the link rate higher than the link rate from
728 			 * the latest EQ_FAIL fallback.
729 			 */
730 			max->link_rate = cur->link_rate;
731 			cur->lane_count = max->lane_count;
732 		} else {
733 			return false;
734 		}
735 		break;
736 	}
737 	default:
738 		return false;
739 	}
740 	return true;
741 }
decide_dp_link_settings(struct dc_link * link,struct dc_link_settings * link_setting,uint32_t req_bw)742 static bool decide_dp_link_settings(struct dc_link *link, struct dc_link_settings *link_setting, uint32_t req_bw)
743 {
744 	struct dc_link_settings initial_link_setting = {
745 		LANE_COUNT_ONE, LINK_RATE_LOW, LINK_SPREAD_DISABLED, false, 0};
746 	struct dc_link_settings current_link_setting =
747 			initial_link_setting;
748 	uint32_t link_bw;
749 
750 	if (req_bw > dp_link_bandwidth_kbps(link, &link->verified_link_cap))
751 		return false;
752 
753 	if (link->preferred_link_setting.link_rate != LINK_RATE_UNKNOWN)
754 		initial_link_setting.link_rate = link->preferred_link_setting.link_rate;
755 
756 	/* search for the minimum link setting that:
757 	 * 1. is supported according to the link training result
758 	 * 2. could support the b/w requested by the timing
759 	 */
760 	while (current_link_setting.link_rate <=
761 			link->verified_link_cap.link_rate) {
762 		link_bw = dp_link_bandwidth_kbps(
763 				link,
764 				&current_link_setting);
765 		if (req_bw <= link_bw) {
766 			*link_setting = current_link_setting;
767 			return true;
768 		}
769 
770 		if (current_link_setting.lane_count <
771 				link->verified_link_cap.lane_count) {
772 			current_link_setting.lane_count =
773 					increase_lane_count(
774 							current_link_setting.lane_count);
775 		} else {
776 			current_link_setting.link_rate =
777 					increase_link_rate(link,
778 							current_link_setting.link_rate);
779 			current_link_setting.lane_count =
780 					initial_link_setting.lane_count;
781 		}
782 	}
783 
784 	return false;
785 }
786 
edp_decide_link_settings(struct dc_link * link,struct dc_link_settings * link_setting,uint32_t req_bw)787 bool edp_decide_link_settings(struct dc_link *link,
788 		struct dc_link_settings *link_setting, uint32_t req_bw)
789 {
790 	struct dc_link_settings initial_link_setting;
791 	struct dc_link_settings current_link_setting;
792 	uint32_t link_bw;
793 
794 	/*
795 	 * edp_supported_link_rates_count is only valid for eDP v1.4 or higher.
796 	 * Per VESA eDP spec, "The DPCD revision for eDP v1.4 is 13h"
797 	 */
798 	if (!edp_is_ilr_optimization_enabled(link)) {
799 		*link_setting = link->verified_link_cap;
800 		return true;
801 	}
802 
803 	memset(&initial_link_setting, 0, sizeof(initial_link_setting));
804 	initial_link_setting.lane_count = LANE_COUNT_ONE;
805 	initial_link_setting.link_rate = link->dpcd_caps.edp_supported_link_rates[0];
806 	initial_link_setting.link_spread = LINK_SPREAD_DISABLED;
807 	initial_link_setting.use_link_rate_set = true;
808 	initial_link_setting.link_rate_set = 0;
809 	current_link_setting = initial_link_setting;
810 
811 	/* search for the minimum link setting that:
812 	 * 1. is supported according to the link training result
813 	 * 2. could support the b/w requested by the timing
814 	 */
815 	while (current_link_setting.link_rate <=
816 			link->verified_link_cap.link_rate) {
817 		link_bw = dp_link_bandwidth_kbps(
818 				link,
819 				&current_link_setting);
820 		if (req_bw <= link_bw) {
821 			*link_setting = current_link_setting;
822 			return true;
823 		}
824 
825 		if (current_link_setting.lane_count <
826 				link->verified_link_cap.lane_count) {
827 			current_link_setting.lane_count =
828 					increase_lane_count(
829 							current_link_setting.lane_count);
830 		} else {
831 			increase_edp_link_rate(link, &current_link_setting);
832 		}
833 	}
834 	return false;
835 }
836 
decide_edp_link_settings_with_dsc(struct dc_link * link,struct dc_link_settings * link_setting,uint32_t req_bw,enum dc_link_rate max_link_rate)837 bool decide_edp_link_settings_with_dsc(struct dc_link *link,
838 		struct dc_link_settings *link_setting,
839 		uint32_t req_bw,
840 		enum dc_link_rate max_link_rate)
841 {
842 	struct dc_link_settings initial_link_setting;
843 	struct dc_link_settings current_link_setting;
844 	uint32_t link_bw;
845 
846 	unsigned int policy = 0;
847 
848 	policy = link->panel_config.dsc.force_dsc_edp_policy;
849 	if (max_link_rate == LINK_RATE_UNKNOWN)
850 		max_link_rate = link->verified_link_cap.link_rate;
851 	/*
852 	 * edp_supported_link_rates_count is only valid for eDP v1.4 or higher.
853 	 * Per VESA eDP spec, "The DPCD revision for eDP v1.4 is 13h"
854 	 */
855 	if (!edp_is_ilr_optimization_enabled(link)) {
856 		/* for DSC enabled case, we search for minimum lane count */
857 		memset(&initial_link_setting, 0, sizeof(initial_link_setting));
858 		initial_link_setting.lane_count = LANE_COUNT_ONE;
859 		initial_link_setting.link_rate = LINK_RATE_LOW;
860 		initial_link_setting.link_spread = LINK_SPREAD_DISABLED;
861 		initial_link_setting.use_link_rate_set = false;
862 		initial_link_setting.link_rate_set = 0;
863 		current_link_setting = initial_link_setting;
864 		if (req_bw > dp_link_bandwidth_kbps(link, &link->verified_link_cap))
865 			return false;
866 
867 		/* search for the minimum link setting that:
868 		 * 1. is supported according to the link training result
869 		 * 2. could support the b/w requested by the timing
870 		 */
871 		while (current_link_setting.link_rate <=
872 				max_link_rate) {
873 			link_bw = dp_link_bandwidth_kbps(
874 					link,
875 					&current_link_setting);
876 			if (req_bw <= link_bw) {
877 				*link_setting = current_link_setting;
878 				return true;
879 			}
880 			if (policy) {
881 				/* minimize lane */
882 				if (current_link_setting.link_rate < max_link_rate) {
883 					increase_edp_link_rate(link, &current_link_setting);
884 				} else {
885 					if (current_link_setting.lane_count <
886 									link->verified_link_cap.lane_count) {
887 						current_link_setting.lane_count =
888 								increase_lane_count(
889 										current_link_setting.lane_count);
890 						current_link_setting.link_rate = initial_link_setting.link_rate;
891 					} else
892 						break;
893 				}
894 			} else {
895 				/* minimize link rate */
896 				if (current_link_setting.lane_count <
897 						link->verified_link_cap.lane_count) {
898 					current_link_setting.lane_count =
899 							increase_lane_count(
900 									current_link_setting.lane_count);
901 				} else {
902 					increase_edp_link_rate(link, &current_link_setting);
903 					current_link_setting.lane_count =
904 							initial_link_setting.lane_count;
905 				}
906 			}
907 		}
908 		return false;
909 	}
910 
911 	/* if optimize edp link is supported */
912 	memset(&initial_link_setting, 0, sizeof(initial_link_setting));
913 	initial_link_setting.lane_count = LANE_COUNT_ONE;
914 	initial_link_setting.link_rate = link->dpcd_caps.edp_supported_link_rates[0];
915 	initial_link_setting.link_spread = LINK_SPREAD_DISABLED;
916 	initial_link_setting.use_link_rate_set = true;
917 	initial_link_setting.link_rate_set = 0;
918 	current_link_setting = initial_link_setting;
919 
920 	/* search for the minimum link setting that:
921 	 * 1. is supported according to the link training result
922 	 * 2. could support the b/w requested by the timing
923 	 */
924 	while (current_link_setting.link_rate <=
925 			max_link_rate) {
926 		link_bw = dp_link_bandwidth_kbps(
927 				link,
928 				&current_link_setting);
929 		if (req_bw <= link_bw) {
930 			*link_setting = current_link_setting;
931 			return true;
932 		}
933 		if (policy) {
934 			/* minimize lane */
935 			if (current_link_setting.link_rate < max_link_rate) {
936 				increase_edp_link_rate(link, &current_link_setting);
937 			} else {
938 				if (current_link_setting.lane_count < link->verified_link_cap.lane_count) {
939 					current_link_setting.lane_count =
940 							increase_lane_count(
941 									current_link_setting.lane_count);
942 					current_link_setting.link_rate_set = initial_link_setting.link_rate_set;
943 					current_link_setting.use_link_rate_set = initial_link_setting.use_link_rate_set;
944 					current_link_setting.link_rate =
945 						link->dpcd_caps.edp_supported_link_rates[current_link_setting.link_rate_set];
946 				} else
947 					break;
948 			}
949 		} else {
950 			/* minimize link rate */
951 			if (current_link_setting.lane_count <
952 					link->verified_link_cap.lane_count) {
953 				current_link_setting.lane_count =
954 						increase_lane_count(
955 								current_link_setting.lane_count);
956 			} else {
957 				increase_edp_link_rate(link, &current_link_setting);
958 				if (current_link_setting.link_rate == LINK_RATE_UNKNOWN)
959 					break;
960 			}
961 		}
962 	}
963 	return false;
964 }
965 
decide_mst_link_settings(const struct dc_link * link,struct dc_link_settings * link_setting)966 static bool decide_mst_link_settings(const struct dc_link *link, struct dc_link_settings *link_setting)
967 {
968 	*link_setting = link->verified_link_cap;
969 	return true;
970 }
971 
link_decide_link_settings(struct dc_stream_state * stream,struct dc_link_settings * link_setting)972 bool link_decide_link_settings(struct dc_stream_state *stream,
973 	struct dc_link_settings *link_setting)
974 {
975 	struct dc_link *link = stream->link;
976 	uint32_t req_bw = dc_bandwidth_in_kbps_from_timing(&stream->timing, dc_link_get_highest_encoding_format(link));
977 
978 	memset(link_setting, 0, sizeof(*link_setting));
979 
980 	if (dc_is_dp_signal(stream->signal)  &&
981 			link->preferred_link_setting.lane_count != LANE_COUNT_UNKNOWN &&
982 			link->preferred_link_setting.link_rate != LINK_RATE_UNKNOWN) {
983 		/* if preferred is specified through AMDDP, use it, if it's enough
984 		 * to drive the mode
985 		 */
986 		*link_setting = link->preferred_link_setting;
987 	} else if (stream->signal == SIGNAL_TYPE_DISPLAY_PORT_MST) {
988 		/* MST doesn't perform link training for now
989 		 * TODO: add MST specific link training routine
990 		 */
991 		decide_mst_link_settings(link, link_setting);
992 	} else if (stream->signal == SIGNAL_TYPE_VIRTUAL) {
993 		link_setting->lane_count = LANE_COUNT_FOUR;
994 		link_setting->link_rate = LINK_RATE_HIGH3;
995 	} else if (link->connector_signal == SIGNAL_TYPE_EDP) {
996 		/* enable edp link optimization for DSC eDP case */
997 		if (stream->timing.flags.DSC) {
998 			enum dc_link_rate max_link_rate = LINK_RATE_UNKNOWN;
999 
1000 			if (link->panel_config.dsc.force_dsc_edp_policy) {
1001 				/* calculate link max link rate cap*/
1002 				struct dc_link_settings tmp_link_setting;
1003 				struct dc_crtc_timing tmp_timing = stream->timing;
1004 				uint32_t orig_req_bw;
1005 
1006 				tmp_link_setting.link_rate = LINK_RATE_UNKNOWN;
1007 				tmp_timing.flags.DSC = 0;
1008 				orig_req_bw = dc_bandwidth_in_kbps_from_timing(&tmp_timing,
1009 						dc_link_get_highest_encoding_format(link));
1010 				edp_decide_link_settings(link, &tmp_link_setting, orig_req_bw);
1011 				max_link_rate = tmp_link_setting.link_rate;
1012 			}
1013 			decide_edp_link_settings_with_dsc(link, link_setting, req_bw, max_link_rate);
1014 		} else {
1015 			edp_decide_link_settings(link, link_setting, req_bw);
1016 		}
1017 	} else {
1018 		decide_dp_link_settings(link, link_setting, req_bw);
1019 	}
1020 
1021 	return link_setting->lane_count != LANE_COUNT_UNKNOWN &&
1022 			link_setting->link_rate != LINK_RATE_UNKNOWN;
1023 }
1024 
link_dp_get_encoding_format(const struct dc_link_settings * link_settings)1025 enum dp_link_encoding link_dp_get_encoding_format(const struct dc_link_settings *link_settings)
1026 {
1027 	if ((link_settings->link_rate >= LINK_RATE_LOW) &&
1028 			(link_settings->link_rate <= LINK_RATE_HIGH3))
1029 		return DP_8b_10b_ENCODING;
1030 	else if ((link_settings->link_rate >= LINK_RATE_UHBR10) &&
1031 			(link_settings->link_rate <= LINK_RATE_UHBR20))
1032 		return DP_128b_132b_ENCODING;
1033 	return DP_UNKNOWN_ENCODING;
1034 }
1035 
mst_decide_link_encoding_format(const struct dc_link * link)1036 enum dp_link_encoding mst_decide_link_encoding_format(const struct dc_link *link)
1037 {
1038 	struct dc_link_settings link_settings = {0};
1039 
1040 	if (!dc_is_dp_signal(link->connector_signal))
1041 		return DP_UNKNOWN_ENCODING;
1042 
1043 	if (link->preferred_link_setting.lane_count !=
1044 			LANE_COUNT_UNKNOWN &&
1045 			link->preferred_link_setting.link_rate !=
1046 					LINK_RATE_UNKNOWN) {
1047 		link_settings = link->preferred_link_setting;
1048 	} else {
1049 		decide_mst_link_settings(link, &link_settings);
1050 	}
1051 
1052 	return link_dp_get_encoding_format(&link_settings);
1053 }
1054 
read_dp_device_vendor_id(struct dc_link * link)1055 static void read_dp_device_vendor_id(struct dc_link *link)
1056 {
1057 	struct dp_device_vendor_id dp_id = {0};
1058 
1059 	/* read IEEE branch device id */
1060 	core_link_read_dpcd(
1061 		link,
1062 		DP_BRANCH_OUI,
1063 		(uint8_t *)&dp_id,
1064 		sizeof(dp_id));
1065 
1066 	link->dpcd_caps.branch_dev_id =
1067 		(dp_id.ieee_oui[0] << 16) +
1068 		(dp_id.ieee_oui[1] << 8) +
1069 		dp_id.ieee_oui[2];
1070 
1071 	memmove(
1072 		link->dpcd_caps.branch_dev_name,
1073 		dp_id.ieee_device_id,
1074 		sizeof(dp_id.ieee_device_id));
1075 }
1076 
wake_up_aux_channel(struct dc_link * link)1077 static enum dc_status wake_up_aux_channel(struct dc_link *link)
1078 {
1079 	enum dc_status status = DC_ERROR_UNEXPECTED;
1080 	uint32_t aux_channel_retry_cnt = 0;
1081 	uint8_t dpcd_power_state = '\0';
1082 
1083 	while (status != DC_OK && aux_channel_retry_cnt < 10) {
1084 		status = core_link_read_dpcd(link, DP_SET_POWER,
1085 				&dpcd_power_state, sizeof(dpcd_power_state));
1086 
1087 		/* Delay 1 ms if AUX CH is in power down state. Based on spec
1088 		 * section 2.3.1.2, if AUX CH may be powered down due to
1089 		 * write to DPCD 600h = 2. Sink AUX CH is monitoring differential
1090 		 * signal and may need up to 1 ms before being able to reply.
1091 		 */
1092 		if (status != DC_OK || dpcd_power_state == DP_SET_POWER_D3) {
1093 			fsleep(1000);
1094 			aux_channel_retry_cnt++;
1095 		}
1096 	}
1097 
1098 	if (status != DC_OK) {
1099 		dpcd_power_state = DP_SET_POWER_D0;
1100 		status = core_link_write_dpcd(
1101 				link,
1102 				DP_SET_POWER,
1103 				&dpcd_power_state,
1104 				sizeof(dpcd_power_state));
1105 
1106 		dpcd_power_state = DP_SET_POWER_D3;
1107 		status = core_link_write_dpcd(
1108 				link,
1109 				DP_SET_POWER,
1110 				&dpcd_power_state,
1111 				sizeof(dpcd_power_state));
1112 		DC_LOG_DC("%s: Failed to power up sink\n", __func__);
1113 		return DC_ERROR_UNEXPECTED;
1114 	}
1115 
1116 	return DC_OK;
1117 }
1118 
read_and_intersect_post_frl_lt_status(struct dc_link * link)1119 static void read_and_intersect_post_frl_lt_status(
1120 	struct dc_link *link)
1121 {
1122 	union autonomous_mode_and_frl_link_status autonomous_mode_caps = {0};
1123 	union hdmi_tx_link_status hdmi_tx_link_status = {0};
1124 	union hdmi_encoded_link_bw hdmi_encoded_link_bw = {0};
1125 
1126 	/* Check if dongle supports regulated autonomous mode. */
1127 	core_link_read_dpcd(link, DP_REGULATED_AUTONOMOUS_MODE_SUPPORTED_AND_HDMI_LINK_TRAINING_STATUS,
1128 		&autonomous_mode_caps.raw, sizeof(autonomous_mode_caps));
1129 
1130 	link->dpcd_caps.dongle_caps.dp_hdmi_regulated_autonomous_mode_support =
1131 			autonomous_mode_caps.bits.REGULATED_AUTONOMOUS_MODE_SUPPORTED;
1132 
1133 	if (link->dpcd_caps.dongle_caps.dp_hdmi_regulated_autonomous_mode_support) {
1134 		DC_LOG_DC("%s: PCON supports regulated autonomous mode.\n", __func__);
1135 
1136 		core_link_read_dpcd(link, DP_PCON_HDMI_TX_LINK_STATUS,
1137 				&hdmi_tx_link_status.raw, sizeof(hdmi_tx_link_status));
1138 	}
1139 
1140 	// Intersect reported max link bw support with the supported link rate post FRL link training
1141 	if (core_link_read_dpcd(link, DP_PCON_HDMI_POST_FRL_STATUS,
1142 			&hdmi_encoded_link_bw.raw, sizeof(hdmi_encoded_link_bw)) == DC_OK) {
1143 
1144 		if (link->dpcd_caps.dongle_caps.dp_hdmi_regulated_autonomous_mode_support &&
1145 				(!hdmi_tx_link_status.bits.HDMI_TX_READY_STATUS ||
1146 						!hdmi_encoded_link_bw.bits.FRL_LINK_TRAINING_FINISHED)) {
1147 			DC_LOG_WARNING("%s: PCON TX link training has not finished.\n", __func__);
1148 
1149 			/* Link training not finished, ignore values from this DPCD reg. */
1150 			return;
1151 		}
1152 
1153 		link->dpcd_caps.dongle_caps.dp_hdmi_frl_max_link_bw_in_kbps = intersect_frl_link_bw_support(
1154 				link->dpcd_caps.dongle_caps.dp_hdmi_frl_max_link_bw_in_kbps,
1155 				hdmi_encoded_link_bw);
1156 		DC_LOG_DC("%s: pcon frl link bw = %u\n", __func__,
1157 			link->dpcd_caps.dongle_caps.dp_hdmi_frl_max_link_bw_in_kbps);
1158 	}
1159 }
1160 
get_active_converter_info(uint8_t data,struct dc_link * link)1161 static void get_active_converter_info(
1162 	uint8_t data, struct dc_link *link)
1163 {
1164 	union dp_downstream_port_present ds_port = { .byte = data };
1165 	memset(&link->dpcd_caps.dongle_caps, 0, sizeof(link->dpcd_caps.dongle_caps));
1166 
1167 	/* decode converter info*/
1168 	if (!ds_port.fields.PORT_PRESENT) {
1169 		link->dpcd_caps.dongle_type = DISPLAY_DONGLE_NONE;
1170 		set_dongle_type(link->ddc,
1171 				link->dpcd_caps.dongle_type);
1172 		link->dpcd_caps.is_branch_dev = false;
1173 		return;
1174 	}
1175 
1176 	/* DPCD 0x5 bit 0 = 1, it indicate it's branch device */
1177 	link->dpcd_caps.is_branch_dev = ds_port.fields.PORT_PRESENT;
1178 
1179 	switch (ds_port.fields.PORT_TYPE) {
1180 	case DOWNSTREAM_VGA:
1181 		link->dpcd_caps.dongle_type = DISPLAY_DONGLE_DP_VGA_CONVERTER;
1182 		break;
1183 	case DOWNSTREAM_DVI_HDMI_DP_PLUS_PLUS:
1184 		/* At this point we don't know is it DVI or HDMI or DP++,
1185 		 * assume DVI.*/
1186 		link->dpcd_caps.dongle_type = DISPLAY_DONGLE_DP_DVI_CONVERTER;
1187 		break;
1188 	default:
1189 		link->dpcd_caps.dongle_type = DISPLAY_DONGLE_NONE;
1190 		break;
1191 	}
1192 
1193 	if (link->dpcd_caps.dpcd_rev.raw >= DPCD_REV_11) {
1194 		uint8_t det_caps[16] = {0}; /* CTS 4.2.2.7 expects source to read Detailed Capabilities Info : 00080h-0008F.*/
1195 		union dwnstream_port_caps_byte0 *port_caps =
1196 			(union dwnstream_port_caps_byte0 *)det_caps;
1197 		if (core_link_read_dpcd(link, DP_DOWNSTREAM_PORT_0,
1198 				det_caps, sizeof(det_caps)) == DC_OK) {
1199 
1200 			switch (port_caps->bits.DWN_STRM_PORTX_TYPE) {
1201 			/*Handle DP case as DONGLE_NONE*/
1202 			case DOWN_STREAM_DETAILED_DP:
1203 				link->dpcd_caps.dongle_type = DISPLAY_DONGLE_NONE;
1204 				break;
1205 			case DOWN_STREAM_DETAILED_VGA:
1206 				link->dpcd_caps.dongle_type =
1207 					DISPLAY_DONGLE_DP_VGA_CONVERTER;
1208 				break;
1209 			case DOWN_STREAM_DETAILED_DVI:
1210 				link->dpcd_caps.dongle_type =
1211 					DISPLAY_DONGLE_DP_DVI_CONVERTER;
1212 				break;
1213 			case DOWN_STREAM_DETAILED_HDMI:
1214 			case DOWN_STREAM_DETAILED_DP_PLUS_PLUS:
1215 				/*Handle DP++ active converter case, process DP++ case as HDMI case according DP1.4 spec*/
1216 				link->dpcd_caps.dongle_type =
1217 					DISPLAY_DONGLE_DP_HDMI_CONVERTER;
1218 
1219 				link->dpcd_caps.dongle_caps.dongle_type = link->dpcd_caps.dongle_type;
1220 				if (ds_port.fields.DETAILED_CAPS) {
1221 
1222 					union dwnstream_port_caps_byte3_hdmi
1223 						hdmi_caps = {.raw = det_caps[3] };
1224 					union dwnstream_port_caps_byte2
1225 						hdmi_color_caps = {.raw = det_caps[2] };
1226 					link->dpcd_caps.dongle_caps.dp_hdmi_max_pixel_clk_in_khz =
1227 						det_caps[1] * 2500;
1228 
1229 					link->dpcd_caps.dongle_caps.is_dp_hdmi_s3d_converter =
1230 						hdmi_caps.bits.FRAME_SEQ_TO_FRAME_PACK;
1231 					/*YCBCR capability only for HDMI case*/
1232 					if (port_caps->bits.DWN_STRM_PORTX_TYPE
1233 							== DOWN_STREAM_DETAILED_HDMI) {
1234 						link->dpcd_caps.dongle_caps.is_dp_hdmi_ycbcr422_pass_through =
1235 								hdmi_caps.bits.YCrCr422_PASS_THROUGH;
1236 						link->dpcd_caps.dongle_caps.is_dp_hdmi_ycbcr420_pass_through =
1237 								hdmi_caps.bits.YCrCr420_PASS_THROUGH;
1238 						link->dpcd_caps.dongle_caps.is_dp_hdmi_ycbcr422_converter =
1239 								hdmi_caps.bits.YCrCr422_CONVERSION;
1240 						link->dpcd_caps.dongle_caps.is_dp_hdmi_ycbcr420_converter =
1241 								hdmi_caps.bits.YCrCr420_CONVERSION;
1242 					}
1243 
1244 					link->dpcd_caps.dongle_caps.dp_hdmi_max_bpc =
1245 						translate_dpcd_max_bpc(
1246 							hdmi_color_caps.bits.MAX_BITS_PER_COLOR_COMPONENT);
1247 
1248 					if (link->dc->caps.dp_hdmi21_pcon_support) {
1249 
1250 						link->dpcd_caps.dongle_caps.dp_hdmi_frl_max_link_bw_in_kbps =
1251 								link_bw_kbps_from_raw_frl_link_rate_data(
1252 										hdmi_color_caps.bits.MAX_ENCODED_LINK_BW_SUPPORT);
1253 
1254 						read_and_intersect_post_frl_lt_status(link);
1255 
1256 						if (link->dpcd_caps.dongle_caps.dp_hdmi_frl_max_link_bw_in_kbps > 0)
1257 							link->dpcd_caps.dongle_caps.extendedCapValid = true;
1258 					}
1259 
1260 					if (link->dpcd_caps.dongle_caps.dp_hdmi_max_pixel_clk_in_khz != 0)
1261 						link->dpcd_caps.dongle_caps.extendedCapValid = true;
1262 				}
1263 
1264 				break;
1265 			}
1266 		}
1267 	}
1268 
1269 	set_dongle_type(link->ddc, link->dpcd_caps.dongle_type);
1270 
1271 	{
1272 		struct dp_sink_hw_fw_revision dp_hw_fw_revision = {0};
1273 
1274 		core_link_read_dpcd(
1275 			link,
1276 			DP_BRANCH_REVISION_START,
1277 			(uint8_t *)&dp_hw_fw_revision,
1278 			sizeof(dp_hw_fw_revision));
1279 
1280 		link->dpcd_caps.branch_hw_revision =
1281 			dp_hw_fw_revision.ieee_hw_rev;
1282 
1283 		memmove(
1284 			link->dpcd_caps.branch_fw_revision,
1285 			dp_hw_fw_revision.ieee_fw_rev,
1286 			sizeof(dp_hw_fw_revision.ieee_fw_rev));
1287 	}
1288 
1289 	core_link_read_dpcd(
1290 		link,
1291 		DP_BRANCH_VENDOR_SPECIFIC_START,
1292 		(uint8_t *)link->dpcd_caps.branch_vendor_specific_data,
1293 		sizeof(link->dpcd_caps.branch_vendor_specific_data));
1294 
1295 	if (link->dpcd_caps.dpcd_rev.raw >= DPCD_REV_14 &&
1296 			link->dpcd_caps.dongle_type != DISPLAY_DONGLE_NONE) {
1297 		union dp_dfp_cap_ext dfp_cap_ext;
1298 		memset(&dfp_cap_ext, '\0', sizeof (dfp_cap_ext));
1299 		core_link_read_dpcd(
1300 				link,
1301 				DP_DFP_CAPABILITY_EXTENSION_SUPPORT,
1302 				dfp_cap_ext.raw,
1303 				sizeof(dfp_cap_ext.raw));
1304 		link->dpcd_caps.dongle_caps.dfp_cap_ext.supported = dfp_cap_ext.fields.supported;
1305 		link->dpcd_caps.dongle_caps.dfp_cap_ext.max_pixel_rate_in_mps =
1306 				dfp_cap_ext.fields.max_pixel_rate_in_mps[0] +
1307 				(dfp_cap_ext.fields.max_pixel_rate_in_mps[1] << 8);
1308 		link->dpcd_caps.dongle_caps.dfp_cap_ext.max_video_h_active_width =
1309 				dfp_cap_ext.fields.max_video_h_active_width[0] +
1310 				(dfp_cap_ext.fields.max_video_h_active_width[1] << 8);
1311 		link->dpcd_caps.dongle_caps.dfp_cap_ext.max_video_v_active_height =
1312 				dfp_cap_ext.fields.max_video_v_active_height[0] +
1313 				(dfp_cap_ext.fields.max_video_v_active_height[1] << 8);
1314 		link->dpcd_caps.dongle_caps.dfp_cap_ext.encoding_format_caps =
1315 				dfp_cap_ext.fields.encoding_format_caps;
1316 		link->dpcd_caps.dongle_caps.dfp_cap_ext.rgb_color_depth_caps =
1317 				dfp_cap_ext.fields.rgb_color_depth_caps;
1318 		link->dpcd_caps.dongle_caps.dfp_cap_ext.ycbcr444_color_depth_caps =
1319 				dfp_cap_ext.fields.ycbcr444_color_depth_caps;
1320 		link->dpcd_caps.dongle_caps.dfp_cap_ext.ycbcr422_color_depth_caps =
1321 				dfp_cap_ext.fields.ycbcr422_color_depth_caps;
1322 		link->dpcd_caps.dongle_caps.dfp_cap_ext.ycbcr420_color_depth_caps =
1323 				dfp_cap_ext.fields.ycbcr420_color_depth_caps;
1324 		DC_LOG_DP2("DFP capability extension is read at link %d", link->link_index);
1325 		DC_LOG_DP2("\tdfp_cap_ext.supported = %s", link->dpcd_caps.dongle_caps.dfp_cap_ext.supported ? "true" : "false");
1326 		DC_LOG_DP2("\tdfp_cap_ext.max_pixel_rate_in_mps = %d", link->dpcd_caps.dongle_caps.dfp_cap_ext.max_pixel_rate_in_mps);
1327 		DC_LOG_DP2("\tdfp_cap_ext.max_video_h_active_width = %d", link->dpcd_caps.dongle_caps.dfp_cap_ext.max_video_h_active_width);
1328 		DC_LOG_DP2("\tdfp_cap_ext.max_video_v_active_height = %d", link->dpcd_caps.dongle_caps.dfp_cap_ext.max_video_v_active_height);
1329 	}
1330 }
1331 
apply_usbc_combo_phy_reset_wa(struct dc_link * link,struct dc_link_settings * link_settings)1332 static void apply_usbc_combo_phy_reset_wa(struct dc_link *link,
1333 		struct dc_link_settings *link_settings)
1334 {
1335 	/* Temporary Renoir-specific workaround PHY will sometimes be in bad
1336 	 * state on hotplugging display from certain USB-C dongle, so add extra
1337 	 * cycle of enabling and disabling the PHY before first link training.
1338 	 */
1339 	struct link_resource link_res = {0};
1340 	enum clock_source_id dp_cs_id = get_clock_source_id(link);
1341 
1342 	dp_enable_link_phy(link, &link_res, link->connector_signal,
1343 			dp_cs_id, link_settings);
1344 	dp_disable_link_phy(link, &link_res, link->connector_signal);
1345 }
1346 
dp_overwrite_extended_receiver_cap(struct dc_link * link)1347 bool dp_overwrite_extended_receiver_cap(struct dc_link *link)
1348 {
1349 	uint8_t dpcd_data[16] = {0};
1350 	uint32_t read_dpcd_retry_cnt = 3;
1351 	enum dc_status status = DC_ERROR_UNEXPECTED;
1352 	union dp_downstream_port_present ds_port = { 0 };
1353 	union down_stream_port_count down_strm_port_count;
1354 	union edp_configuration_cap edp_config_cap;
1355 
1356 	int i;
1357 
1358 	for (i = 0; i < read_dpcd_retry_cnt; i++) {
1359 		status = core_link_read_dpcd(
1360 				link,
1361 				DP_DPCD_REV,
1362 				dpcd_data,
1363 				sizeof(dpcd_data));
1364 		if (status == DC_OK)
1365 			break;
1366 	}
1367 
1368 	link->dpcd_caps.dpcd_rev.raw =
1369 		dpcd_data[DP_DPCD_REV - DP_DPCD_REV];
1370 
1371 	if (dpcd_data[DP_MAX_LANE_COUNT - DP_DPCD_REV] == 0)
1372 		return false;
1373 
1374 	ds_port.byte = dpcd_data[DP_DOWNSTREAMPORT_PRESENT -
1375 			DP_DPCD_REV];
1376 
1377 	get_active_converter_info(ds_port.byte, link);
1378 
1379 	down_strm_port_count.raw = dpcd_data[DP_DOWN_STREAM_PORT_COUNT -
1380 			DP_DPCD_REV];
1381 
1382 	link->dpcd_caps.allow_invalid_MSA_timing_param =
1383 		down_strm_port_count.bits.IGNORE_MSA_TIMING_PARAM;
1384 
1385 	link->dpcd_caps.max_ln_count.raw = dpcd_data[
1386 		DP_MAX_LANE_COUNT - DP_DPCD_REV];
1387 
1388 	link->dpcd_caps.max_down_spread.raw = dpcd_data[
1389 		DP_MAX_DOWNSPREAD - DP_DPCD_REV];
1390 
1391 	link->reported_link_cap.lane_count =
1392 		link->dpcd_caps.max_ln_count.bits.MAX_LANE_COUNT;
1393 	link->reported_link_cap.link_rate = dpcd_data[
1394 		DP_MAX_LINK_RATE - DP_DPCD_REV];
1395 	link->reported_link_cap.link_spread =
1396 		link->dpcd_caps.max_down_spread.bits.MAX_DOWN_SPREAD ?
1397 		LINK_SPREAD_05_DOWNSPREAD_30KHZ : LINK_SPREAD_DISABLED;
1398 
1399 	edp_config_cap.raw = dpcd_data[
1400 		DP_EDP_CONFIGURATION_CAP - DP_DPCD_REV];
1401 	link->dpcd_caps.panel_mode_edp =
1402 		edp_config_cap.bits.ALT_SCRAMBLER_RESET;
1403 	link->dpcd_caps.dpcd_display_control_capable =
1404 		edp_config_cap.bits.DPCD_DISPLAY_CONTROL_CAPABLE;
1405 
1406 	return true;
1407 }
1408 
dpcd_set_source_specific_data(struct dc_link * link)1409 void dpcd_set_source_specific_data(struct dc_link *link)
1410 {
1411 	if (!link->dc->vendor_signature.is_valid) {
1412 		enum dc_status __maybe_unused result_write_min_hblank = DC_NOT_SUPPORTED;
1413 		struct dpcd_amd_signature amd_signature = {0};
1414 		struct dpcd_amd_device_id amd_device_id = {0};
1415 
1416 		if (link->is_dds) {
1417 			uint8_t dpcd_dp_edp_backlight_mode = 0;
1418 
1419 			/*
1420 			 * Write 0 to bits 0:1 for dp_edp_backlight_mode_set register
1421 			 * if platform is DDS
1422 			 */
1423 			core_link_read_dpcd(link, DP_EDP_BACKLIGHT_MODE_SET_REGISTER,
1424 				&dpcd_dp_edp_backlight_mode, sizeof(uint8_t));
1425 			dpcd_dp_edp_backlight_mode &= ~0x3;
1426 
1427 			core_link_write_dpcd(link, DP_EDP_BACKLIGHT_MODE_SET_REGISTER,
1428 				&dpcd_dp_edp_backlight_mode, sizeof(uint8_t));
1429 		}
1430 
1431 		amd_device_id.device_id_byte1 =
1432 				(uint8_t)(link->ctx->asic_id.chip_id);
1433 		amd_device_id.device_id_byte2 =
1434 				(uint8_t)(link->ctx->asic_id.chip_id >> 8);
1435 		amd_device_id.dce_version =
1436 				(uint8_t)(link->ctx->dce_version);
1437 		amd_device_id.dal_version_byte1 = 0x0; // needed? where to get?
1438 		amd_device_id.dal_version_byte2 = 0x0; // needed? where to get?
1439 
1440 		core_link_read_dpcd(link, DP_SOURCE_OUI,
1441 				(uint8_t *)(&amd_signature),
1442 				sizeof(amd_signature));
1443 
1444 		if (!((amd_signature.AMD_IEEE_TxSignature_byte1 == 0x0) &&
1445 			(amd_signature.AMD_IEEE_TxSignature_byte2 == 0x0) &&
1446 			(amd_signature.AMD_IEEE_TxSignature_byte3 == 0x1A))) {
1447 
1448 			amd_signature.AMD_IEEE_TxSignature_byte1 = 0x0;
1449 			amd_signature.AMD_IEEE_TxSignature_byte2 = 0x0;
1450 			amd_signature.AMD_IEEE_TxSignature_byte3 = 0x1A;
1451 
1452 			core_link_write_dpcd(link, DP_SOURCE_OUI,
1453 				(uint8_t *)(&amd_signature),
1454 				sizeof(amd_signature));
1455 		}
1456 
1457 		core_link_write_dpcd(link, DP_SOURCE_OUI+0x03,
1458 				(uint8_t *)(&amd_device_id),
1459 				sizeof(amd_device_id));
1460 
1461 		if (link->ctx->dce_version >= DCN_VERSION_2_0 &&
1462 			link->dc->caps.min_horizontal_blanking_period != 0) {
1463 
1464 			uint8_t hblank_size = (uint8_t)link->dc->caps.min_horizontal_blanking_period;
1465 
1466 			result_write_min_hblank = core_link_write_dpcd(link,
1467 				DP_SOURCE_MINIMUM_HBLANK_SUPPORTED, (uint8_t *)(&hblank_size),
1468 				sizeof(hblank_size));
1469 		}
1470 		DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
1471 							WPP_BIT_FLAG_DC_DETECTION_DP_CAPS,
1472 							"result=%u link_index=%u enum dce_version=%d DPCD=0x%04X min_hblank=%u branch_dev_id=0x%x branch_dev_name='%c%c%c%c%c%c'",
1473 							result_write_min_hblank,
1474 							link->link_index,
1475 							link->ctx->dce_version,
1476 							DP_SOURCE_MINIMUM_HBLANK_SUPPORTED,
1477 							link->dc->caps.min_horizontal_blanking_period,
1478 							link->dpcd_caps.branch_dev_id,
1479 							link->dpcd_caps.branch_dev_name[0],
1480 							link->dpcd_caps.branch_dev_name[1],
1481 							link->dpcd_caps.branch_dev_name[2],
1482 							link->dpcd_caps.branch_dev_name[3],
1483 							link->dpcd_caps.branch_dev_name[4],
1484 							link->dpcd_caps.branch_dev_name[5]);
1485 	} else {
1486 		core_link_write_dpcd(link, DP_SOURCE_OUI,
1487 				link->dc->vendor_signature.data.raw,
1488 				sizeof(link->dc->vendor_signature.data.raw));
1489 	}
1490 }
1491 
dpcd_write_cable_id_to_dprx(struct dc_link * link)1492 void dpcd_write_cable_id_to_dprx(struct dc_link *link)
1493 {
1494 	if (!link->dpcd_caps.channel_coding_cap.bits.DP_128b_132b_SUPPORTED ||
1495 			link->dpcd_caps.cable_id.raw == 0 ||
1496 			link->dprx_states.cable_id_written)
1497 		return;
1498 
1499 	core_link_write_dpcd(link, DP_CABLE_ATTRIBUTES_UPDATED_BY_DPTX,
1500 			&link->dpcd_caps.cable_id.raw,
1501 			sizeof(link->dpcd_caps.cable_id.raw));
1502 
1503 	link->dprx_states.cable_id_written = 1;
1504 }
1505 
get_usbc_cable_id(struct dc_link * link,union dp_cable_id * cable_id)1506 static bool get_usbc_cable_id(struct dc_link *link, union dp_cable_id *cable_id)
1507 {
1508 	union dmub_rb_cmd cmd;
1509 
1510 	if (!link->ctx->dmub_srv ||
1511 			link->ep_type != DISPLAY_ENDPOINT_PHY ||
1512 			link->link_enc->features.flags.bits.DP_IS_USB_C == 0)
1513 		return false;
1514 
1515 	memset(&cmd, 0, sizeof(cmd));
1516 	cmd.cable_id.header.type = DMUB_CMD_GET_USBC_CABLE_ID;
1517 	cmd.cable_id.header.payload_bytes = sizeof(cmd.cable_id.data);
1518 	cmd.cable_id.data.input.phy_inst = resource_transmitter_to_phy_idx(
1519 			link->dc, link->link_enc->transmitter);
1520 	if (dc_wake_and_execute_dmub_cmd(link->dc->ctx, &cmd, DM_DMUB_WAIT_TYPE_WAIT_WITH_REPLY) &&
1521 			cmd.cable_id.header.ret_status == 1) {
1522 		cable_id->raw = cmd.cable_id.data.output_raw;
1523 		DC_LOG_DC("usbc_cable_id = %d.\n", cable_id->raw);
1524 	}
1525 	return cmd.cable_id.header.ret_status == 1;
1526 }
1527 
retrieve_cable_id(struct dc_link * link)1528 static void retrieve_cable_id(struct dc_link *link)
1529 {
1530 	union dp_cable_id usbc_cable_id = {0};
1531 
1532 	link->dpcd_caps.cable_id.raw = 0;
1533 	core_link_read_dpcd(link, DP_CABLE_ATTRIBUTES_UPDATED_BY_DPRX,
1534 			&link->dpcd_caps.cable_id.raw, sizeof(uint8_t));
1535 
1536 	if (get_usbc_cable_id(link, &usbc_cable_id))
1537 		link->dpcd_caps.cable_id = intersect_cable_id(
1538 				&link->dpcd_caps.cable_id, &usbc_cable_id);
1539 }
1540 
read_is_mst_supported(struct dc_link * link)1541 bool read_is_mst_supported(struct dc_link *link)
1542 {
1543 	bool mst          = false;
1544 	enum dc_status st = DC_OK;
1545 	union dpcd_rev rev;
1546 	union mstm_cap cap;
1547 
1548 	if (link->preferred_training_settings.mst_enable &&
1549 		*link->preferred_training_settings.mst_enable == false) {
1550 		return false;
1551 	}
1552 
1553 	rev.raw = 0;
1554 	cap.raw = 0;
1555 
1556 	st = core_link_read_dpcd(link, DP_DPCD_REV, &rev.raw,
1557 			sizeof(rev));
1558 
1559 	if (st == DC_OK && rev.raw >= DPCD_REV_12) {
1560 
1561 		st = core_link_read_dpcd(link, DP_MSTM_CAP,
1562 				&cap.raw, sizeof(cap));
1563 		if (st == DC_OK && cap.bits.MST_CAP == 1)
1564 			mst = true;
1565 	}
1566 	return mst;
1567 
1568 }
1569 
1570 /* Read additional sink caps defined in source specific DPCD area
1571  * This function currently only reads from SinkCapability address (DP_SOURCE_SINK_CAP)
1572  * TODO: Add FS caps and read from DP_SOURCE_SINK_FS_CAP as well
1573  */
dpcd_read_sink_ext_caps(struct dc_link * link)1574 static bool dpcd_read_sink_ext_caps(struct dc_link *link)
1575 {
1576 	uint8_t dpcd_data = 0;
1577 	uint8_t edp_general_cap2 = 0;
1578 
1579 	if (!link)
1580 		return false;
1581 
1582 	if (core_link_read_dpcd(link, DP_SOURCE_SINK_CAP, &dpcd_data, 1) != DC_OK)
1583 		return false;
1584 
1585 	link->dpcd_sink_ext_caps.raw = dpcd_data;
1586 	if (link->is_dds && !link->dpcd_sink_ext_caps.bits.oled) {
1587 		link->dpcd_sink_ext_caps.raw = 0;
1588 		return false;
1589 	}
1590 
1591 	if (core_link_read_dpcd(link, DP_EDP_GENERAL_CAP_2, &edp_general_cap2, 1) != DC_OK)
1592 		return false;
1593 
1594 	link->dpcd_caps.panel_luminance_control = (edp_general_cap2 & DP_EDP_PANEL_LUMINANCE_CONTROL_CAPABLE) != 0;
1595 
1596 	return true;
1597 }
1598 
retrieve_vesa_replay_su_info(struct dc_link * link)1599 static void retrieve_vesa_replay_su_info(struct dc_link *link)
1600 {
1601 	uint8_t dpcd_data = 0;
1602 
1603 	core_link_read_dpcd(link,
1604 		DP_PR_SU_X_GRANULARITY_LOW,
1605 		&dpcd_data,
1606 		sizeof(dpcd_data));
1607 	link->dpcd_caps.vesa_replay_su_info.pr_su_x_granularity = dpcd_data;
1608 
1609 	core_link_read_dpcd(link,
1610 		DP_PR_SU_X_GRANULARITY_HIGH,
1611 		&dpcd_data,
1612 		sizeof(dpcd_data));
1613 	link->dpcd_caps.vesa_replay_su_info.pr_su_x_granularity |= (dpcd_data << 8);
1614 
1615 	core_link_read_dpcd(link,
1616 		DP_PR_SU_Y_GRANULARITY,
1617 		&dpcd_data,
1618 		sizeof(dpcd_data));
1619 	link->dpcd_caps.vesa_replay_su_info.pr_su_y_granularity = dpcd_data;
1620 
1621 	core_link_read_dpcd(link,
1622 		DP_PR_SU_Y_GRANULARITY_EXTENDED_CAP_LOW,
1623 		&dpcd_data,
1624 		sizeof(dpcd_data));
1625 	link->dpcd_caps.vesa_replay_su_info.pr_su_y_granularity_extended_caps = dpcd_data;
1626 
1627 	core_link_read_dpcd(link,
1628 		DP_PR_SU_Y_GRANULARITY_EXTENDED_CAP_HIGH,
1629 		&dpcd_data,
1630 		sizeof(dpcd_data));
1631 	link->dpcd_caps.vesa_replay_su_info.pr_su_y_granularity_extended_caps |= (dpcd_data << 8);
1632 }
1633 
dp_retrieve_lttpr_cap(struct dc_link * link)1634 enum dc_status dp_retrieve_lttpr_cap(struct dc_link *link)
1635 {
1636 	uint8_t lttpr_dpcd_data[10] = {0};
1637 	enum dc_status status;
1638 	bool is_lttpr_present;
1639 	uint32_t lttpr_count;
1640 	uint32_t closest_lttpr_offset;
1641 
1642 	/* Logic to determine LTTPR support*/
1643 	bool vbios_lttpr_interop = link->dc->caps.vbios_lttpr_aware;
1644 
1645 	if (!vbios_lttpr_interop || !link->dc->caps.extended_aux_timeout_support)
1646 		return DC_NOT_SUPPORTED;
1647 
1648 	/* By reading LTTPR capability, RX assumes that we will enable
1649 	 * LTTPR extended aux timeout if LTTPR is present.
1650 	 */
1651 	status = core_link_read_dpcd(
1652 			link,
1653 			DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV,
1654 			lttpr_dpcd_data,
1655 			sizeof(lttpr_dpcd_data));
1656 
1657 	link->dpcd_caps.lttpr_caps.revision.raw =
1658 			lttpr_dpcd_data[DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV -
1659 							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
1660 
1661 	link->dpcd_caps.lttpr_caps.max_link_rate =
1662 			lttpr_dpcd_data[DP_MAX_LINK_RATE_PHY_REPEATER -
1663 							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
1664 
1665 	link->dpcd_caps.lttpr_caps.phy_repeater_cnt =
1666 			lttpr_dpcd_data[DP_PHY_REPEATER_CNT -
1667 							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
1668 
1669 	link->dpcd_caps.lttpr_caps.max_lane_count =
1670 			lttpr_dpcd_data[DP_MAX_LANE_COUNT_PHY_REPEATER -
1671 							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
1672 
1673 	link->dpcd_caps.lttpr_caps.mode =
1674 			lttpr_dpcd_data[DP_PHY_REPEATER_MODE -
1675 							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
1676 
1677 	link->dpcd_caps.lttpr_caps.max_ext_timeout =
1678 			lttpr_dpcd_data[DP_PHY_REPEATER_EXTENDED_WAIT_TIMEOUT -
1679 							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
1680 	link->dpcd_caps.lttpr_caps.main_link_channel_coding.raw =
1681 			lttpr_dpcd_data[DP_MAIN_LINK_CHANNEL_CODING_PHY_REPEATER -
1682 							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
1683 
1684 	link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.raw =
1685 			lttpr_dpcd_data[DP_PHY_REPEATER_128B132B_RATES -
1686 							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
1687 
1688 	link->dpcd_caps.lttpr_caps.alpm.raw =
1689 			lttpr_dpcd_data[DP_LTTPR_ALPM_CAPABILITIES -
1690 							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
1691 
1692 	lttpr_count = dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
1693 
1694 	/* If this chip cap is set, at least one retimer must exist in the chain
1695 	 * Override count to 1 if we receive a known bad count (0 or an invalid value) */
1696 	if (((link->chip_caps & AMD_EXT_DISPLAY_PATH_CAPS__EXT_CHIP_MASK) == AMD_EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) &&
1697 			lttpr_count == 0) {
1698 		/* If you see this message consistently, either the host platform has FIXED_VS flag
1699 		 * incorrectly configured or the sink device is returning an invalid count.
1700 		 */
1701 		DC_LOG_ERROR("lttpr_caps phy_repeater_cnt is 0x%x, forcing it to 0x80.",
1702 			     link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
1703 		link->dpcd_caps.lttpr_caps.phy_repeater_cnt = 0x80;
1704 		lttpr_count = 1;
1705 		DC_LOG_DC("lttpr_caps forced phy_repeater_cnt = %d\n", link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
1706 	}
1707 
1708 	is_lttpr_present = dp_is_lttpr_present(link);
1709 
1710 	DC_LOG_DC("is_lttpr_present = %d\n", is_lttpr_present);
1711 
1712 	if (is_lttpr_present) {
1713 		CONN_DATA_DETECT(link, lttpr_dpcd_data, sizeof(lttpr_dpcd_data), "LTTPR Caps: ");
1714 
1715 		// Identify closest LTTPR to determine if workarounds required for known embedded LTTPR
1716 		closest_lttpr_offset = dp_get_closest_lttpr_offset(lttpr_count);
1717 
1718 		core_link_read_dpcd(link, (DP_LTTPR_IEEE_OUI + closest_lttpr_offset),
1719 				link->dpcd_caps.lttpr_caps.lttpr_ieee_oui, sizeof(link->dpcd_caps.lttpr_caps.lttpr_ieee_oui));
1720 		core_link_read_dpcd(link, (DP_LTTPR_DEVICE_ID + closest_lttpr_offset),
1721 				link->dpcd_caps.lttpr_caps.lttpr_device_id, sizeof(link->dpcd_caps.lttpr_caps.lttpr_device_id));
1722 
1723 		if (lttpr_count > 1) {
1724 			CONN_DATA_DETECT(link, link->dpcd_caps.lttpr_caps.lttpr_ieee_oui, sizeof(link->dpcd_caps.lttpr_caps.lttpr_ieee_oui),
1725 					"Closest LTTPR To Host's IEEE OUI: ");
1726 			CONN_DATA_DETECT(link, link->dpcd_caps.lttpr_caps.lttpr_device_id, sizeof(link->dpcd_caps.lttpr_caps.lttpr_device_id),
1727 					"Closest LTTPR To Host's LTTPR Device ID: ");
1728 		} else {
1729 			CONN_DATA_DETECT(link, link->dpcd_caps.lttpr_caps.lttpr_ieee_oui, sizeof(link->dpcd_caps.lttpr_caps.lttpr_ieee_oui),
1730 					"LTTPR IEEE OUI: ");
1731 			CONN_DATA_DETECT(link, link->dpcd_caps.lttpr_caps.lttpr_device_id, sizeof(link->dpcd_caps.lttpr_caps.lttpr_device_id),
1732 					"LTTPR Device ID: ");
1733 		}
1734 	}
1735 
1736 	return status;
1737 }
1738 
retrieve_link_cap(struct dc_link * link)1739 static bool retrieve_link_cap(struct dc_link *link)
1740 {
1741 	/* DP_ADAPTER_CAP - DP_DPCD_REV + 1 == 16 and also DP_DSC_BITS_PER_PIXEL_INC - DP_DSC_SUPPORT + 1 == 16,
1742 	 * which means size 16 will be good for both of those DPCD register block reads
1743 	 */
1744 	uint8_t dpcd_data[16];
1745 	/*Only need to read 1 byte starting from DP_DPRX_FEATURE_ENUMERATION_LIST.
1746 	 */
1747 	uint8_t dpcd_dprx_data = '\0';
1748 
1749 	struct dp_device_vendor_id sink_id;
1750 	union down_stream_port_count down_strm_port_count;
1751 	union edp_configuration_cap edp_config_cap;
1752 	union dp_downstream_port_present ds_port = { 0 };
1753 	enum dc_status status = DC_ERROR_UNEXPECTED;
1754 	uint32_t read_dpcd_retry_cnt = 20;
1755 	int i;
1756 	struct dp_sink_hw_fw_revision dp_hw_fw_revision;
1757 	const uint32_t post_oui_delay = 30; // 30ms
1758 	bool is_fec_supported = false;
1759 	bool is_dsc_basic_supported = false;
1760 	bool is_dsc_passthrough_supported = false;
1761 
1762 	memset(dpcd_data, '\0', sizeof(dpcd_data));
1763 	memset(&down_strm_port_count,
1764 		'\0', sizeof(union down_stream_port_count));
1765 	memset(&edp_config_cap, '\0',
1766 		sizeof(union edp_configuration_cap));
1767 
1768 	/* if extended timeout is supported in hardware,
1769 	 * default to LTTPR timeout (3.2ms) first as a W/A for DP link layer
1770 	 * CTS 4.2.1.1 regression introduced by CTS specs requirement update.
1771 	 */
1772 	try_to_configure_aux_timeout(link->ddc,
1773 			LINK_AUX_DEFAULT_LTTPR_TIMEOUT_PERIOD);
1774 
1775 	status = dp_retrieve_lttpr_cap(link);
1776 
1777 	if (status != DC_OK) {
1778 		status = wake_up_aux_channel(link);
1779 		if (status == DC_OK)
1780 			dp_retrieve_lttpr_cap(link);
1781 		else
1782 			return false;
1783 	}
1784 
1785 	if (dp_is_lttpr_present(link)) {
1786 		configure_lttpr_mode_transparent(link);
1787 
1788 		// Echo TOTAL_LTTPR_CNT back downstream
1789 		core_link_write_dpcd(
1790 				link,
1791 				DP_TOTAL_LTTPR_CNT,
1792 				&link->dpcd_caps.lttpr_caps.phy_repeater_cnt,
1793 				sizeof(link->dpcd_caps.lttpr_caps.phy_repeater_cnt));
1794 	}
1795 
1796 	dpcd_set_source_specific_data(link);
1797 
1798 	for (i = 0; i < read_dpcd_retry_cnt; i++) {
1799 		/*
1800 		 * Sink may need to configure internals based on vendor, so allow some
1801 		 * time before proceeding with possibly vendor specific transactions
1802 		 */
1803 		msleep(post_oui_delay);
1804 		status = core_link_read_dpcd(
1805 				link,
1806 				DP_DPCD_REV,
1807 				dpcd_data,
1808 				sizeof(dpcd_data));
1809 		if (status == DC_OK)
1810 			break;
1811 	}
1812 
1813 
1814 	if (status != DC_OK) {
1815 		dm_error("%s: Read receiver caps dpcd data failed.\n", __func__);
1816 		return false;
1817 	}
1818 
1819 	if (!dp_is_lttpr_present(link))
1820 		try_to_configure_aux_timeout(link->ddc, LINK_AUX_DEFAULT_TIMEOUT_PERIOD);
1821 
1822 
1823 	{
1824 		union training_aux_rd_interval aux_rd_interval;
1825 
1826 		aux_rd_interval.raw =
1827 			dpcd_data[DP_TRAINING_AUX_RD_INTERVAL];
1828 
1829 		link->dpcd_caps.ext_receiver_cap_field_present =
1830 				aux_rd_interval.bits.EXT_RECEIVER_CAP_FIELD_PRESENT == 1;
1831 
1832 		if (aux_rd_interval.bits.EXT_RECEIVER_CAP_FIELD_PRESENT == 1) {
1833 			uint8_t ext_cap_data[16];
1834 
1835 			memset(ext_cap_data, '\0', sizeof(ext_cap_data));
1836 			for (i = 0; i < read_dpcd_retry_cnt; i++) {
1837 				status = core_link_read_dpcd(
1838 				link,
1839 				DP_DP13_DPCD_REV,
1840 				ext_cap_data,
1841 				sizeof(ext_cap_data));
1842 				if (status == DC_OK) {
1843 					memcpy(dpcd_data, ext_cap_data, sizeof(dpcd_data));
1844 					break;
1845 				}
1846 			}
1847 			if (status != DC_OK)
1848 				dm_error("%s: Read extend caps data failed, use cap from dpcd 0.\n", __func__);
1849 		}
1850 	}
1851 
1852 	link->dpcd_caps.dpcd_rev.raw =
1853 			dpcd_data[DP_DPCD_REV - DP_DPCD_REV];
1854 
1855 	if (link->dpcd_caps.ext_receiver_cap_field_present) {
1856 		for (i = 0; i < read_dpcd_retry_cnt; i++) {
1857 			status = core_link_read_dpcd(
1858 					link,
1859 					DP_DPRX_FEATURE_ENUMERATION_LIST,
1860 					&dpcd_dprx_data,
1861 					sizeof(dpcd_dprx_data));
1862 			if (status == DC_OK)
1863 				break;
1864 		}
1865 
1866 		link->dpcd_caps.dprx_feature.raw = dpcd_dprx_data;
1867 
1868 		if (status != DC_OK)
1869 			dm_error("%s: Read DPRX feature list failed.\n", __func__);
1870 
1871 		/* AdaptiveSyncCapability  */
1872 		dpcd_dprx_data = 0;
1873 		for (i = 0; i < read_dpcd_retry_cnt; i++) {
1874 			status = core_link_read_dpcd(
1875 					link, DP_DPRX_FEATURE_ENUMERATION_LIST_CONT_1,
1876 					&dpcd_dprx_data, sizeof(dpcd_dprx_data));
1877 			if (status == DC_OK)
1878 				break;
1879 		}
1880 
1881 		link->dpcd_caps.adaptive_sync_caps.dp_adap_sync_caps.raw = dpcd_dprx_data;
1882 
1883 		if (status != DC_OK)
1884 			dm_error("%s: Read DPRX feature list_1 failed. Addr:%#x\n",
1885 					__func__, DP_DPRX_FEATURE_ENUMERATION_LIST_CONT_1);
1886 	}
1887 	else {
1888 		link->dpcd_caps.dprx_feature.raw = 0;
1889 	}
1890 
1891 	/* Error condition checking...
1892 	 * It is impossible for Sink to report Max Lane Count = 0.
1893 	 * It is possible for Sink to report Max Link Rate = 0, if it is
1894 	 * an eDP device that is reporting specialized link rates in the
1895 	 * SUPPORTED_LINK_RATE table.
1896 	 */
1897 	if (dpcd_data[DP_MAX_LANE_COUNT - DP_DPCD_REV] == 0)
1898 		return false;
1899 
1900 	ds_port.byte = dpcd_data[DP_DOWNSTREAMPORT_PRESENT -
1901 				 DP_DPCD_REV];
1902 
1903 	read_dp_device_vendor_id(link);
1904 
1905 	/* TODO - decouple raw mst capability from policy decision */
1906 	link->dpcd_caps.is_mst_capable = read_is_mst_supported(link);
1907 	DC_LOG_DC("%s: MST_Support: %s\n", __func__, str_yes_no(link->dpcd_caps.is_mst_capable));
1908 
1909 	/* Some MST docks seem to NAK I2C writes to segment pointer with mot=0. */
1910 	if (link->dpcd_caps.is_mst_capable)
1911 		link->wa_flags.dp_mot_reset_segment = true;
1912 	else
1913 		link->wa_flags.dp_mot_reset_segment = false;
1914 
1915 	get_active_converter_info(ds_port.byte, link);
1916 
1917 	dp_wa_power_up_0010FA(link, dpcd_data, sizeof(dpcd_data));
1918 
1919 	down_strm_port_count.raw = dpcd_data[DP_DOWN_STREAM_PORT_COUNT -
1920 				 DP_DPCD_REV];
1921 
1922 	link->dpcd_caps.allow_invalid_MSA_timing_param =
1923 		down_strm_port_count.bits.IGNORE_MSA_TIMING_PARAM;
1924 
1925 	link->dpcd_caps.max_ln_count.raw = dpcd_data[
1926 		DP_MAX_LANE_COUNT - DP_DPCD_REV];
1927 
1928 	link->dpcd_caps.max_down_spread.raw = dpcd_data[
1929 		DP_MAX_DOWNSPREAD - DP_DPCD_REV];
1930 
1931 	link->reported_link_cap.lane_count =
1932 		link->dpcd_caps.max_ln_count.bits.MAX_LANE_COUNT;
1933 	link->reported_link_cap.link_rate = get_link_rate_from_max_link_bw(
1934 			dpcd_data[DP_MAX_LINK_RATE - DP_DPCD_REV]);
1935 	link->reported_link_cap.link_spread =
1936 		link->dpcd_caps.max_down_spread.bits.MAX_DOWN_SPREAD ?
1937 		LINK_SPREAD_05_DOWNSPREAD_30KHZ : LINK_SPREAD_DISABLED;
1938 
1939 	edp_config_cap.raw = dpcd_data[
1940 		DP_EDP_CONFIGURATION_CAP - DP_DPCD_REV];
1941 	link->dpcd_caps.panel_mode_edp =
1942 		edp_config_cap.bits.ALT_SCRAMBLER_RESET;
1943 	link->dpcd_caps.dpcd_display_control_capable =
1944 		edp_config_cap.bits.DPCD_DISPLAY_CONTROL_CAPABLE;
1945 	link->dpcd_caps.channel_coding_cap.raw =
1946 			dpcd_data[DP_MAIN_LINK_CHANNEL_CODING - DP_DPCD_REV];
1947 	link->test_pattern_enabled = false;
1948 	link->compliance_test_state.raw = 0;
1949 
1950 	link->dpcd_caps.receive_port0_cap.raw[0] =
1951 			dpcd_data[DP_RECEIVE_PORT_0_CAP_0 - DP_DPCD_REV];
1952 	link->dpcd_caps.receive_port0_cap.raw[1] =
1953 			dpcd_data[DP_RECEIVE_PORT_0_BUFFER_SIZE - DP_DPCD_REV];
1954 
1955 	/* read sink count */
1956 	core_link_read_dpcd(link,
1957 			DP_SINK_COUNT,
1958 			&link->dpcd_caps.sink_count.raw,
1959 			sizeof(link->dpcd_caps.sink_count.raw));
1960 
1961 	/* read sink ieee oui */
1962 	core_link_read_dpcd(link,
1963 			DP_SINK_OUI,
1964 			(uint8_t *)(&sink_id),
1965 			sizeof(sink_id));
1966 
1967 	link->dpcd_caps.sink_dev_id =
1968 			(sink_id.ieee_oui[0] << 16) +
1969 			(sink_id.ieee_oui[1] << 8) +
1970 			(sink_id.ieee_oui[2]);
1971 
1972 	memmove(
1973 		link->dpcd_caps.sink_dev_id_str,
1974 		sink_id.ieee_device_id,
1975 		sizeof(sink_id.ieee_device_id));
1976 
1977 	core_link_read_dpcd(
1978 		link,
1979 		DP_SINK_HW_REVISION_START,
1980 		(uint8_t *)&dp_hw_fw_revision,
1981 		sizeof(dp_hw_fw_revision));
1982 
1983 	link->dpcd_caps.sink_hw_revision =
1984 		dp_hw_fw_revision.ieee_hw_rev;
1985 
1986 	memmove(
1987 		link->dpcd_caps.sink_fw_revision,
1988 		dp_hw_fw_revision.ieee_fw_rev,
1989 		sizeof(dp_hw_fw_revision.ieee_fw_rev));
1990 
1991 	/* Quirk for Retina panels: wrong DP_MAX_LINK_RATE */
1992 	{
1993 		uint8_t str_mbp_2018[] = { 101, 68, 21, 103, 98, 97 };
1994 		uint8_t fwrev_mbp_2018[] = { 7, 4 };
1995 		uint8_t fwrev_mbp_2018_vega[] = { 8, 4 };
1996 
1997 		/* We also check for the firmware revision as 16,1 models have an
1998 		 * identical device id and are incorrectly quirked otherwise.
1999 		 */
2000 		if ((link->dpcd_caps.sink_dev_id == 0x0010fa) &&
2001 		    !memcmp(link->dpcd_caps.sink_dev_id_str, str_mbp_2018,
2002 			     sizeof(str_mbp_2018)) &&
2003 		    (!memcmp(link->dpcd_caps.sink_fw_revision, fwrev_mbp_2018,
2004 			     sizeof(fwrev_mbp_2018)) ||
2005 		    !memcmp(link->dpcd_caps.sink_fw_revision, fwrev_mbp_2018_vega,
2006 			     sizeof(fwrev_mbp_2018_vega)))) {
2007 			link->reported_link_cap.link_rate = LINK_RATE_RBR2;
2008 		}
2009 	}
2010 
2011 	memset(&link->dpcd_caps.dsc_caps, '\0',
2012 			sizeof(link->dpcd_caps.dsc_caps));
2013 	memset(&link->dpcd_caps.fec_cap, '\0', sizeof(link->dpcd_caps.fec_cap));
2014 	/* Read DSC and FEC sink capabilities if DP revision is 1.4 and up */
2015 	if (link->dpcd_caps.dpcd_rev.raw >= DPCD_REV_14) {
2016 		status = core_link_read_dpcd(
2017 				link,
2018 				DP_FEC_CAPABILITY,
2019 				&link->dpcd_caps.fec_cap.raw,
2020 				sizeof(link->dpcd_caps.fec_cap.raw));
2021 		if (status != DC_OK)
2022 			DC_LOG_ERROR("%s:%d: core_link_read_dpcd (DP_FEC_CAPABILITY) failed\n", __func__, __LINE__);
2023 
2024 		status = core_link_read_dpcd(
2025 				link,
2026 				DP_DSC_SUPPORT,
2027 				link->dpcd_caps.dsc_caps.dsc_basic_caps.raw,
2028 				sizeof(link->dpcd_caps.dsc_caps.dsc_basic_caps.raw));
2029 		if (status == DC_OK) {
2030 			is_fec_supported = link->dpcd_caps.fec_cap.bits.FEC_CAPABLE;
2031 			is_dsc_basic_supported = link->dpcd_caps.dsc_caps.dsc_basic_caps.fields.dsc_support.DSC_SUPPORT;
2032 			is_dsc_passthrough_supported = link->dpcd_caps.dsc_caps.dsc_basic_caps.fields.dsc_support.DSC_PASSTHROUGH_SUPPORT;
2033 			DC_LOG_DC("%s: FEC_Sink_Support: %s\n", __func__,
2034 				  str_yes_no(is_fec_supported));
2035 			DC_LOG_DC("%s: DSC_Basic_Sink_Support: %s\n", __func__,
2036 				  str_yes_no(is_dsc_basic_supported));
2037 			DC_LOG_DC("%s: DSC_Passthrough_Sink_Support: %s\n", __func__,
2038 				  str_yes_no(is_dsc_passthrough_supported));
2039 		}
2040 		if (link->dpcd_caps.dongle_type != DISPLAY_DONGLE_NONE) {
2041 			status = core_link_read_dpcd(
2042 					link,
2043 					DP_DSC_BRANCH_OVERALL_THROUGHPUT_0,
2044 					link->dpcd_caps.dsc_caps.dsc_branch_decoder_caps.raw,
2045 					sizeof(link->dpcd_caps.dsc_caps.dsc_branch_decoder_caps.raw));
2046 			if (status != DC_OK)
2047 				DC_LOG_ERROR("%s:%d: core_link_read_dpcd (DP_DSC_BRANCH_OVERALL_THROUGHPUT_0) failed\n", __func__, __LINE__);
2048 
2049 			DC_LOG_DSC("DSC branch decoder capability is read at link %d", link->link_index);
2050 			DC_LOG_DSC("\tBRANCH_OVERALL_THROUGHPUT_0 = 0x%02x",
2051 					link->dpcd_caps.dsc_caps.dsc_branch_decoder_caps.fields.BRANCH_OVERALL_THROUGHPUT_0);
2052 			DC_LOG_DSC("\tBRANCH_OVERALL_THROUGHPUT_1 = 0x%02x",
2053 					link->dpcd_caps.dsc_caps.dsc_branch_decoder_caps.fields.BRANCH_OVERALL_THROUGHPUT_1);
2054 			DC_LOG_DSC("\tBRANCH_MAX_LINE_WIDTH 0x%02x",
2055 					link->dpcd_caps.dsc_caps.dsc_branch_decoder_caps.fields.BRANCH_MAX_LINE_WIDTH);
2056 		}
2057 
2058 		/* Apply work around to disable FEC and DSC for USB4 tunneling in TBT3 compatibility mode
2059 		 * only if required.
2060 		 */
2061 		if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA &&
2062 				link->dc->debug.dpia_debug.bits.enable_force_tbt3_work_around &&
2063 				link->dpcd_caps.is_branch_dev &&
2064 				link->dpcd_caps.branch_dev_id == DP_BRANCH_DEVICE_ID_90CC24 &&
2065 				link->dpcd_caps.branch_hw_revision == DP_BRANCH_HW_REV_10 &&
2066 				(link->dpcd_caps.fec_cap.bits.FEC_CAPABLE ||
2067 				link->dpcd_caps.dsc_caps.dsc_basic_caps.fields.dsc_support.DSC_SUPPORT)) {
2068 			/* A TBT3 device is expected to report no support for FEC or DSC to a USB4 DPIA.
2069 			 * Clear FEC and DSC capabilities as a work around if that is not the case.
2070 			 */
2071 			link->wa_flags.dpia_forced_tbt3_mode = true;
2072 			memset(&link->dpcd_caps.dsc_caps, '\0', sizeof(link->dpcd_caps.dsc_caps));
2073 			memset(&link->dpcd_caps.fec_cap, '\0', sizeof(link->dpcd_caps.fec_cap));
2074 			DC_LOG_DSC("Clear DSC SUPPORT for USB4 link(%d) in TBT3 compatibility mode", link->link_index);
2075 		} else
2076 			link->wa_flags.dpia_forced_tbt3_mode = false;
2077 	}
2078 
2079 	if (!dpcd_read_sink_ext_caps(link))
2080 		link->dpcd_sink_ext_caps.raw = 0;
2081 
2082 	if (link->dpcd_caps.channel_coding_cap.bits.DP_128b_132b_SUPPORTED) {
2083 		DC_LOG_DP2("128b/132b encoding is supported at link %d", link->link_index);
2084 
2085 		/* Read 128b/132b suppoerted link rates */
2086 		core_link_read_dpcd(link,
2087 				DP_128B132B_SUPPORTED_LINK_RATES,
2088 				&link->dpcd_caps.dp_128b_132b_supported_link_rates.raw,
2089 				sizeof(link->dpcd_caps.dp_128b_132b_supported_link_rates.raw));
2090 		if (link->dpcd_caps.dp_128b_132b_supported_link_rates.bits.UHBR20)
2091 			link->reported_link_cap.link_rate = LINK_RATE_UHBR20;
2092 		else if (link->dpcd_caps.dp_128b_132b_supported_link_rates.bits.UHBR13_5)
2093 			link->reported_link_cap.link_rate = LINK_RATE_UHBR13_5;
2094 		else if (link->dpcd_caps.dp_128b_132b_supported_link_rates.bits.UHBR10)
2095 			link->reported_link_cap.link_rate = LINK_RATE_UHBR10;
2096 		else
2097 			dm_error("%s: Invalid RX 128b_132b_supported_link_rates\n", __func__);
2098 		DC_LOG_DP2("128b/132b supported link rates is read at link %d", link->link_index);
2099 		DC_LOG_DP2("\tmax 128b/132b link rate support is %d.%d GHz",
2100 				link->reported_link_cap.link_rate / 100,
2101 				link->reported_link_cap.link_rate % 100);
2102 
2103 		core_link_read_dpcd(link,
2104 				DP_SINK_VIDEO_FALLBACK_FORMATS,
2105 				&link->dpcd_caps.fallback_formats.raw,
2106 				sizeof(link->dpcd_caps.fallback_formats.raw));
2107 		DC_LOG_DP2("sink video fallback format is read at link %d", link->link_index);
2108 		if (link->dpcd_caps.fallback_formats.bits.dp_1920x1080_60Hz_24bpp_support)
2109 			DC_LOG_DP2("\t1920x1080@60Hz 24bpp fallback format supported");
2110 		if (link->dpcd_caps.fallback_formats.bits.dp_1280x720_60Hz_24bpp_support)
2111 			DC_LOG_DP2("\t1280x720@60Hz 24bpp fallback format supported");
2112 		if (link->dpcd_caps.fallback_formats.bits.dp_1024x768_60Hz_24bpp_support)
2113 			DC_LOG_DP2("\t1024x768@60Hz 24bpp fallback format supported");
2114 		if (link->dpcd_caps.fallback_formats.raw == 0) {
2115 			DC_LOG_DP2("\tno supported fallback formats, assume 1920x1080@60Hz 24bpp is supported");
2116 			link->dpcd_caps.fallback_formats.bits.dp_1920x1080_60Hz_24bpp_support = 1;
2117 		}
2118 
2119 		core_link_read_dpcd(link,
2120 				DP_FEC_CAPABILITY_1,
2121 				&link->dpcd_caps.fec_cap1.raw,
2122 				sizeof(link->dpcd_caps.fec_cap1.raw));
2123 		DC_LOG_DP2("FEC CAPABILITY 1 is read at link %d", link->link_index);
2124 		if (link->dpcd_caps.fec_cap1.bits.AGGREGATED_ERROR_COUNTERS_CAPABLE)
2125 			DC_LOG_DP2("\tFEC aggregated error counters are supported");
2126 	}
2127 
2128 	core_link_read_dpcd(link,
2129 			DPCD_MAX_UNCOMPRESSED_PIXEL_RATE_CAP,
2130 			link->dpcd_caps.max_uncompressed_pixel_rate_cap.raw,
2131 			sizeof(link->dpcd_caps.max_uncompressed_pixel_rate_cap.raw));
2132 
2133 	core_link_read_dpcd(link,
2134 			DP_PANEL_REPLAY_CAPABILITY_SUPPORT,
2135 			&link->dpcd_caps.vesa_replay_caps_supported.raw,
2136 			sizeof(link->dpcd_caps.vesa_replay_caps_supported.raw));
2137 
2138 	core_link_read_dpcd(link,
2139 			DP_PANEL_REPLAY_CAPABILITY,
2140 			&link->dpcd_caps.vesa_replay_caps.raw,
2141 			sizeof(link->dpcd_caps.vesa_replay_caps.raw));
2142 
2143 	/* Read VESA Panel Replay Selective Update caps */
2144 	retrieve_vesa_replay_su_info(link);
2145 
2146 	/* Read DP tunneling information. */
2147 	status = dpcd_get_tunneling_device_data(link);
2148 	if (status != DC_OK)
2149 		DC_LOG_DP2("%s: Read DP tunneling device data failed.\n", __func__);
2150 
2151 	retrieve_cable_id(link);
2152 	dpcd_write_cable_id_to_dprx(link);
2153 
2154 	/* Connectivity log: detection */
2155 	CONN_DATA_DETECT(link, dpcd_data, sizeof(dpcd_data), "Rx Caps: ");
2156 
2157 	return true;
2158 }
2159 
detect_dp_sink_caps(struct dc_link * link)2160 bool detect_dp_sink_caps(struct dc_link *link)
2161 {
2162 	return retrieve_link_cap(link);
2163 }
2164 
detect_edp_sink_caps(struct dc_link * link)2165 void detect_edp_sink_caps(struct dc_link *link)
2166 {
2167 	uint8_t supported_link_rates[16];
2168 	uint32_t entry;
2169 	uint32_t link_rate_in_khz;
2170 	enum dc_link_rate link_rate = LINK_RATE_UNKNOWN;
2171 	uint8_t backlight_adj_cap = 0;
2172 	uint8_t general_edp_cap = 0;
2173 
2174 	retrieve_link_cap(link);
2175 	link->dpcd_caps.edp_supported_link_rates_count = 0;
2176 	memset(supported_link_rates, 0, sizeof(supported_link_rates));
2177 
2178 	/*
2179 	 * edp_supported_link_rates_count is only valid for eDP v1.4 or higher.
2180 	 * Per VESA eDP spec, "The DPCD revision for eDP v1.4 is 13h"
2181 	 */
2182 	if (link->dpcd_caps.dpcd_rev.raw >= DPCD_REV_13) {
2183 		// Read DPCD 00010h - 0001Fh 16 bytes at one shot
2184 		core_link_read_dpcd(link, DP_SUPPORTED_LINK_RATES,
2185 							supported_link_rates, sizeof(supported_link_rates));
2186 
2187 		for (entry = 0; entry < 16; entry += 2) {
2188 			// DPCD register reports per-lane link rate = 16-bit link rate capability
2189 			// value X 200 kHz. Need multiplier to find link rate in kHz.
2190 			link_rate_in_khz = (supported_link_rates[entry+1] * 0x100 +
2191 										supported_link_rates[entry]) * 200;
2192 
2193 			DC_LOG_DC("%s: eDP v1.4 supported sink rates: [%d] %d kHz\n", __func__,
2194 				  entry / 2, link_rate_in_khz);
2195 
2196 			if (link_rate_in_khz != 0) {
2197 				link_rate = linkRateInKHzToLinkRateMultiplier(link_rate_in_khz);
2198 				link->dpcd_caps.edp_supported_link_rates[link->dpcd_caps.edp_supported_link_rates_count] = link_rate;
2199 				link->dpcd_caps.edp_supported_link_rates_count++;
2200 			}
2201 		}
2202 	}
2203 
2204 	core_link_read_dpcd(link, DP_EDP_BACKLIGHT_ADJUSTMENT_CAP,
2205 						&backlight_adj_cap, sizeof(backlight_adj_cap));
2206 
2207 	link->dpcd_caps.dynamic_backlight_capable_edp =
2208 				(backlight_adj_cap & DP_EDP_DYNAMIC_BACKLIGHT_CAP) ? true : false;
2209 
2210 	core_link_read_dpcd(link, DP_EDP_GENERAL_CAP_1,
2211 						&general_edp_cap, sizeof(general_edp_cap));
2212 
2213 	link->dpcd_caps.set_power_state_capable_edp =
2214 				(general_edp_cap & DP_EDP_SET_POWER_CAP) ? true : false;
2215 
2216 	set_default_brightness_aux(link);
2217 
2218 	core_link_read_dpcd(link, DP_EDP_DPCD_REV,
2219 		&link->dpcd_caps.edp_rev,
2220 		sizeof(link->dpcd_caps.edp_rev));
2221 	/*
2222 	 * PSR is only valid for eDP v1.3 or higher.
2223 	 */
2224 	if (link->dpcd_caps.edp_rev >= DP_EDP_13) {
2225 		core_link_read_dpcd(link, DP_PSR_SUPPORT,
2226 			&link->dpcd_caps.psr_info.psr_version,
2227 			sizeof(link->dpcd_caps.psr_info.psr_version));
2228 		if (link->dpcd_caps.sink_dev_id == DP_BRANCH_DEVICE_ID_001CF8)
2229 			core_link_read_dpcd(link, DP_FORCE_PSRSU_CAPABILITY,
2230 						&link->dpcd_caps.psr_info.force_psrsu_cap,
2231 						sizeof(link->dpcd_caps.psr_info.force_psrsu_cap));
2232 		core_link_read_dpcd(link, DP_PSR_CAPS,
2233 			&link->dpcd_caps.psr_info.psr_dpcd_caps.raw,
2234 			sizeof(link->dpcd_caps.psr_info.psr_dpcd_caps.raw));
2235 		if (link->dpcd_caps.psr_info.psr_dpcd_caps.bits.Y_COORDINATE_REQUIRED) {
2236 			core_link_read_dpcd(link, DP_PSR2_SU_Y_GRANULARITY,
2237 				&link->dpcd_caps.psr_info.psr2_su_y_granularity_cap,
2238 				sizeof(link->dpcd_caps.psr_info.psr2_su_y_granularity_cap));
2239 		}
2240 	}
2241 
2242 	/*
2243 	 * ALPM is only valid for eDP v1.4 or higher.
2244 	 */
2245 	if (link->dpcd_caps.dpcd_rev.raw >= DP_EDP_14)
2246 		core_link_read_dpcd(link, DP_RECEIVER_ALPM_CAP,
2247 			&link->dpcd_caps.alpm_caps.raw,
2248 			sizeof(link->dpcd_caps.alpm_caps.raw));
2249 
2250 	/*
2251 	 * Read REPLAY info
2252 	 */
2253 	core_link_read_dpcd(link, DP_SINK_PR_PIXEL_DEVIATION_PER_LINE,
2254 			&link->dpcd_caps.pr_info.pixel_deviation_per_line,
2255 			sizeof(link->dpcd_caps.pr_info.pixel_deviation_per_line));
2256 	core_link_read_dpcd(link, DP_SINK_PR_MAX_NUMBER_OF_DEVIATION_LINE,
2257 			&link->dpcd_caps.pr_info.max_deviation_line,
2258 			sizeof(link->dpcd_caps.pr_info.max_deviation_line));
2259 
2260 	/*
2261 	 * OLED Emission Rate info
2262 	 */
2263 	if (link->dpcd_sink_ext_caps.bits.emission_output)
2264 		core_link_read_dpcd(link, DP_SINK_EMISSION_RATE,
2265 				(uint8_t *)&link->dpcd_caps.edp_oled_emission_rate,
2266 				sizeof(link->dpcd_caps.edp_oled_emission_rate));
2267 
2268 	/*
2269 	 * Read DRR granularity
2270 	 */
2271 	core_link_read_dpcd(link, DP_SINK_DRR_GRANULARITY,
2272 			(uint8_t *)&link->dpcd_caps.drr_granularity,
2273 			sizeof(link->dpcd_caps.drr_granularity));
2274 
2275 	/*
2276 	 * Read Multi-SST (Single Stream Transport) capability
2277 	 * for eDP version 1.4 or higher.
2278 	 */
2279 	if (link->dpcd_caps.dpcd_rev.raw >= DP_EDP_14)
2280 		core_link_read_dpcd(
2281 			link,
2282 			DP_EDP_MSO_LINK_CAPABILITIES,
2283 			(uint8_t *)&link->dpcd_caps.mso_cap_sst_links_supported,
2284 			sizeof(link->dpcd_caps.mso_cap_sst_links_supported));
2285 	/*
2286 	 * Read eDP general capability 2
2287 	 */
2288 	core_link_read_dpcd(link, DP_EDP_GENERAL_CAP_2,
2289 			(uint8_t *)&link->dpcd_caps.dp_edp_general_cap_2,
2290 			sizeof(link->dpcd_caps.dp_edp_general_cap_2));
2291 }
2292 
dp_get_max_link_enc_cap(const struct dc_link * link,struct dc_link_settings * max_link_enc_cap)2293 bool dp_get_max_link_enc_cap(const struct dc_link *link, struct dc_link_settings *max_link_enc_cap)
2294 {
2295 	struct resource_context *res_ctx = &link->dc->current_state->res_ctx;
2296 	struct resource_pool *res_pool = link->dc->res_pool;
2297 	struct link_encoder *link_enc = get_temp_dio_link_enc(res_ctx, res_pool, link);
2298 
2299 	if (!max_link_enc_cap) {
2300 		DC_LOG_ERROR("%s: Could not return max link encoder caps", __func__);
2301 		return false;
2302 	}
2303 
2304 	if (!link->dc->config.unify_link_enc_assignment)
2305 		link_enc = link_enc_cfg_get_link_enc(link);
2306 	ASSERT(link_enc);
2307 
2308 	if (link_enc && link_enc->funcs->get_max_link_cap) {
2309 		link_enc->funcs->get_max_link_cap(link_enc, max_link_enc_cap);
2310 		return true;
2311 	}
2312 
2313 	DC_LOG_ERROR("%s: Max link encoder caps unknown", __func__);
2314 	max_link_enc_cap->lane_count = 1;
2315 	max_link_enc_cap->link_rate = 6;
2316 	return false;
2317 }
2318 
dp_get_verified_link_cap(const struct dc_link * link)2319 const struct dc_link_settings *dp_get_verified_link_cap(
2320 		const struct dc_link *link)
2321 {
2322 	if (link->preferred_link_setting.lane_count != LANE_COUNT_UNKNOWN &&
2323 			link->preferred_link_setting.link_rate != LINK_RATE_UNKNOWN)
2324 		return &link->preferred_link_setting;
2325 	return &link->verified_link_cap;
2326 }
2327 
dp_get_max_link_cap(struct dc_link * link)2328 struct dc_link_settings dp_get_max_link_cap(struct dc_link *link)
2329 {
2330 	struct dc_link_settings max_link_cap = {0};
2331 	enum dc_lane_count lttpr_max_lane_count;
2332 	enum dc_link_rate lttpr_max_link_rate;
2333 	enum dc_link_rate cable_max_link_rate;
2334 	struct resource_context *res_ctx = &link->dc->current_state->res_ctx;
2335 	struct resource_pool *res_pool = link->dc->res_pool;
2336 	struct link_encoder *link_enc = get_temp_dio_link_enc(res_ctx, res_pool, link);
2337 	bool is_uhbr13_5_supported = true;
2338 
2339 	if (!link->dc->config.unify_link_enc_assignment)
2340 		link_enc = link_enc_cfg_get_link_enc(link);
2341 	ASSERT(link_enc);
2342 
2343 	/* get max link encoder capability */
2344 	if (link_enc)
2345 		link_enc->funcs->get_max_link_cap(link_enc, &max_link_cap);
2346 
2347 	/* Lower link settings based on sink's link cap */
2348 	if (link->reported_link_cap.lane_count < max_link_cap.lane_count)
2349 		max_link_cap.lane_count =
2350 				link->reported_link_cap.lane_count;
2351 	if (link->reported_link_cap.link_rate < max_link_cap.link_rate)
2352 		max_link_cap.link_rate =
2353 				link->reported_link_cap.link_rate;
2354 	if (link->reported_link_cap.link_spread <
2355 			max_link_cap.link_spread)
2356 		max_link_cap.link_spread =
2357 				link->reported_link_cap.link_spread;
2358 
2359 	if (!link->dpcd_caps.dp_128b_132b_supported_link_rates.bits.UHBR13_5)
2360 		is_uhbr13_5_supported = false;
2361 
2362 	/* Lower link settings based on cable attributes
2363 	 * Cable ID is a DP2 feature to identify max certified link rate that
2364 	 * a cable can carry. The cable identification method requires both
2365 	 * cable and display hardware support. Since the specs comes late, it is
2366 	 * anticipated that the first round of DP2 cables and displays may not
2367 	 * be fully compatible to reliably return cable ID data. Therefore the
2368 	 * decision of our cable id policy is that if the cable can return non
2369 	 * zero cable id data, we will take cable's link rate capability into
2370 	 * account. However if we get zero data, the cable link rate capability
2371 	 * is considered inconclusive. In this case, we will not take cable's
2372 	 * capability into account to avoid of over limiting hardware capability
2373 	 * from users. The max overall link rate capability is still determined
2374 	 * after actual dp pre-training. Cable id is considered as an auxiliary
2375 	 * method of determining max link bandwidth capability.
2376 	 */
2377 	cable_max_link_rate = get_cable_max_link_rate(link);
2378 
2379 	if (!link->dc->debug.ignore_cable_id &&
2380 			cable_max_link_rate != LINK_RATE_UNKNOWN) {
2381 		if (cable_max_link_rate < max_link_cap.link_rate)
2382 			max_link_cap.link_rate = cable_max_link_rate;
2383 
2384 		if (!link->dpcd_caps.cable_id.bits.UHBR13_5_CAPABILITY &&
2385 				link->dpcd_caps.cable_id.bits.CABLE_TYPE >= 2)
2386 			is_uhbr13_5_supported = false;
2387 	}
2388 
2389 	/* account for lttpr repeaters cap
2390 	 * notes: repeaters do not snoop in the DPRX Capabilities addresses (3.6.3).
2391 	 */
2392 	if (dp_is_lttpr_present(link)) {
2393 
2394 		/* Some LTTPR devices do not report valid DPCD revisions, if so, do not take it's link cap into consideration. */
2395 		if (link->dpcd_caps.lttpr_caps.revision.raw >= DPCD_REV_14) {
2396 			lttpr_max_lane_count = get_lttpr_max_lane_count(link);
2397 
2398 			if (lttpr_max_lane_count < max_link_cap.lane_count)
2399 				max_link_cap.lane_count = lttpr_max_lane_count;
2400 
2401 			lttpr_max_link_rate = get_lttpr_max_link_rate(link);
2402 
2403 			if (lttpr_max_link_rate < max_link_cap.link_rate)
2404 				max_link_cap.link_rate = lttpr_max_link_rate;
2405 
2406 			if (!link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.bits.UHBR13_5)
2407 				is_uhbr13_5_supported = false;
2408 		}
2409 
2410 		DC_LOG_HW_LINK_TRAINING("%s\n Training with LTTPR,  max_lane count %d max_link rate %d \n",
2411 						__func__,
2412 						max_link_cap.lane_count,
2413 						max_link_cap.link_rate);
2414 	}
2415 
2416 	if (max_link_cap.link_rate == LINK_RATE_UHBR13_5 &&
2417 			!is_uhbr13_5_supported)
2418 		max_link_cap.link_rate = LINK_RATE_UHBR10;
2419 
2420 	if (link_dp_get_encoding_format(&max_link_cap) == DP_128b_132b_ENCODING &&
2421 			link->dc->debug.disable_uhbr)
2422 		max_link_cap.link_rate = LINK_RATE_HIGH3;
2423 
2424 	return max_link_cap;
2425 }
2426 
dp_verify_link_cap(struct dc_link * link,struct dc_link_settings * known_limit_link_setting,int * fail_count)2427 static bool dp_verify_link_cap(
2428 	struct dc_link *link,
2429 	struct dc_link_settings *known_limit_link_setting,
2430 	int *fail_count)
2431 {
2432 	struct dc_link_settings cur_link_settings = {0};
2433 	struct dc_link_settings max_link_settings = *known_limit_link_setting;
2434 	bool success = false;
2435 	bool skip_video_pattern;
2436 	enum clock_source_id dp_cs_id = get_clock_source_id(link);
2437 	enum link_training_result status = LINK_TRAINING_SUCCESS;
2438 	union hpd_irq_data irq_data;
2439 	struct link_resource link_res;
2440 
2441 	memset(&irq_data, 0, sizeof(irq_data));
2442 	cur_link_settings = max_link_settings;
2443 
2444 	/* Grant extended timeout request */
2445 	if (dp_is_lttpr_present(link) && link->dpcd_caps.lttpr_caps.max_ext_timeout > 0) {
2446 		uint8_t grant = link->dpcd_caps.lttpr_caps.max_ext_timeout & 0x80;
2447 
2448 		core_link_write_dpcd(link, DP_PHY_REPEATER_EXTENDED_WAIT_TIMEOUT, &grant, sizeof(grant));
2449 	}
2450 
2451 	do {
2452 		if (!get_temp_dp_link_res(link, &link_res, &cur_link_settings))
2453 			continue;
2454 
2455 		skip_video_pattern = cur_link_settings.link_rate != LINK_RATE_LOW;
2456 		dp_enable_link_phy(
2457 				link,
2458 				&link_res,
2459 				link->connector_signal,
2460 				dp_cs_id,
2461 				&cur_link_settings);
2462 
2463 		status = dp_perform_link_training(
2464 				link,
2465 				&link_res,
2466 				&cur_link_settings,
2467 				skip_video_pattern);
2468 
2469 		if (status == LINK_TRAINING_SUCCESS) {
2470 			success = true;
2471 			fsleep(1000);
2472 			if (dp_read_hpd_rx_irq_data(link, &irq_data) == DC_OK &&
2473 					dp_parse_link_loss_status(
2474 							link,
2475 							&irq_data))
2476 				(*fail_count)++;
2477 		} else if (status == LINK_TRAINING_LINK_LOSS) {
2478 			success = true;
2479 			(*fail_count)++;
2480 		} else {
2481 			(*fail_count)++;
2482 		}
2483 		dp_trace_lt_total_count_increment(link, true);
2484 		dp_trace_lt_result_update(link, status, true);
2485 		dp_disable_link_phy(link, &link_res, link->connector_signal);
2486 	} while (!success && decide_fallback_link_setting(link,
2487 			&max_link_settings, &cur_link_settings, status));
2488 
2489 	link->verified_link_cap = success ?
2490 			cur_link_settings : fail_safe_link_settings;
2491 	return success;
2492 }
2493 
dp_verify_link_cap_with_retries(struct dc_link * link,struct dc_link_settings * known_limit_link_setting,int attempts)2494 bool dp_verify_link_cap_with_retries(
2495 	struct dc_link *link,
2496 	struct dc_link_settings *known_limit_link_setting,
2497 	int attempts)
2498 {
2499 	int i = 0;
2500 	bool success = false;
2501 	int fail_count = 0;
2502 	struct dc_link_settings last_verified_link_cap = fail_safe_link_settings;
2503 
2504 	dp_trace_detect_lt_init(link);
2505 
2506 	DC_LOG_HW_LINK_TRAINING("%s: Link[%d]  LinkRate=0x%x LaneCount=%d",
2507 		__func__, link->link_index,
2508 		known_limit_link_setting->link_rate,
2509 		known_limit_link_setting->lane_count);
2510 
2511 	if (link->link_enc && link->link_enc->features.flags.bits.DP_IS_USB_C &&
2512 			link->dc->debug.usbc_combo_phy_reset_wa)
2513 		apply_usbc_combo_phy_reset_wa(link, known_limit_link_setting);
2514 
2515 	dp_trace_set_lt_start_timestamp(link, false);
2516 	for (i = 0; i < attempts; i++) {
2517 		enum dc_connection_type type = dc_connection_none;
2518 
2519 		memset(&link->verified_link_cap, 0,
2520 				sizeof(struct dc_link_settings));
2521 		if (link->link_enc && (!link_detect_connection_type(link, &type) || type == dc_connection_none)) {
2522 			link->verified_link_cap = fail_safe_link_settings;
2523 			break;
2524 		} else if (dp_verify_link_cap(link, known_limit_link_setting, &fail_count)) {
2525 			last_verified_link_cap = link->verified_link_cap;
2526 			if (fail_count == 0) {
2527 				success = true;
2528 				break;
2529 			}
2530 		} else {
2531 			link->verified_link_cap = last_verified_link_cap;
2532 		}
2533 
2534 		/* For Dp tunneling link, a pending HPD means that we have a race condition between processing
2535 		 * current link and processing the pending HPD. Since the training is failed, we should just brak
2536 		 * the loop so that we have chance to process the pending HPD.
2537 		 */
2538 		if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA && link->is_hpd_pending)
2539 			break;
2540 
2541 		fsleep(10 * 1000);
2542 	}
2543 
2544 	dp_trace_lt_fail_count_update(link, fail_count, true);
2545 	dp_trace_set_lt_end_timestamp(link, true);
2546 
2547 	DC_LOG_HW_LINK_TRAINING("%s: Link[%d]  Exit. is_success=%d  fail_count=%d",
2548 		__func__, link->link_index,
2549 		success,
2550 		fail_count);
2551 
2552 	return success;
2553 }
2554 
2555 /*
2556  * Check if there is a native DP or passive DP-HDMI dongle connected
2557  */
dp_is_sink_present(struct dc_link * link)2558 bool dp_is_sink_present(struct dc_link *link)
2559 {
2560 	enum gpio_result gpio_result;
2561 	uint32_t clock_pin = 0;
2562 	uint8_t retry = 0;
2563 	struct ddc *ddc;
2564 
2565 	enum connector_id connector_id =
2566 		dal_graphics_object_id_get_connector_id(link->link_id);
2567 
2568 	bool present =
2569 		((connector_id == CONNECTOR_ID_DISPLAY_PORT) ||
2570 		(connector_id == CONNECTOR_ID_EDP) ||
2571 		(connector_id == CONNECTOR_ID_USBC));
2572 
2573 	ddc = get_ddc_pin(link->ddc);
2574 
2575 	if (!ddc) {
2576 		BREAK_TO_DEBUGGER();
2577 		return present;
2578 	}
2579 
2580 	/* Open GPIO and set it to I2C mode */
2581 	/* Note: this GpioMode_Input will be converted
2582 	 * to GpioConfigType_I2cAuxDualMode in GPIO component,
2583 	 * which indicates we need additional delay
2584 	 */
2585 
2586 	if (dal_ddc_open(ddc, GPIO_MODE_INPUT,
2587 			 GPIO_DDC_CONFIG_TYPE_MODE_I2C) != GPIO_RESULT_OK) {
2588 		dal_ddc_close(ddc);
2589 
2590 		return present;
2591 	}
2592 
2593 	/*
2594 	 * Read GPIO: DP sink is present if both clock and data pins are zero
2595 	 *
2596 	 * [W/A] plug-unplug DP cable, sometimes customer board has
2597 	 * one short pulse on clk_pin(1V, < 1ms). DP will be config to HDMI/DVI
2598 	 * then monitor can't br light up. Add retry 3 times
2599 	 * But in real passive dongle, it need additional 3ms to detect
2600 	 */
2601 	do {
2602 		gpio_result = dal_gpio_get_value(ddc->pin_clock, &clock_pin);
2603 		ASSERT(gpio_result == GPIO_RESULT_OK);
2604 		if (clock_pin)
2605 			fsleep(1000);
2606 		else
2607 			break;
2608 	} while (retry++ < 3);
2609 
2610 	present = (gpio_result == GPIO_RESULT_OK) && !clock_pin;
2611 
2612 	dal_ddc_close(ddc);
2613 
2614 	return present;
2615 }
2616 
dp_get_lttpr_count(struct dc_link * link)2617 uint8_t dp_get_lttpr_count(struct dc_link *link)
2618 {
2619 	if (dp_is_lttpr_present(link))
2620 		return dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
2621 
2622 	return 0;
2623 }
2624 
edp_get_alpm_support(struct dc_link * link,bool * auxless_support,bool * auxwake_support)2625 void edp_get_alpm_support(struct dc_link *link,
2626 	bool *auxless_support,
2627 	bool *auxwake_support)
2628 {
2629 	bool lttpr_present = dp_is_lttpr_present(link);
2630 
2631 	if (auxless_support == NULL || auxwake_support == NULL)
2632 		return;
2633 
2634 	*auxless_support = false;
2635 	*auxwake_support = false;
2636 
2637 	if (!dc_is_embedded_signal(link->connector_signal))
2638 		return;
2639 
2640 	if (link->dpcd_caps.alpm_caps.bits.AUX_LESS_ALPM_CAP) {
2641 		if (lttpr_present) {
2642 			if (link->dpcd_caps.lttpr_caps.alpm.bits.AUX_LESS_ALPM_SUPPORTED)
2643 				*auxless_support = true;
2644 		} else
2645 			*auxless_support = true;
2646 	}
2647 
2648 	if (link->dpcd_caps.alpm_caps.bits.AUX_WAKE_ALPM_CAP) {
2649 		if (!lttpr_present)
2650 			*auxwake_support = true;
2651 	}
2652 }
2653