1/*	$NetBSD: amdgpu_atombios_dp.c,v 1.4 2021/12/18 23:44:58 riastradh Exp $	*/
2
3/*
4 * Copyright 2007-8 Advanced Micro Devices, Inc.
5 * Copyright 2008 Red Hat Inc.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 *
25 * Authors: Dave Airlie
26 *          Alex Deucher
27 *          Jerome Glisse
28 */
29
30#include <sys/cdefs.h>
31__KERNEL_RCSID(0, "$NetBSD: amdgpu_atombios_dp.c,v 1.4 2021/12/18 23:44:58 riastradh Exp $");
32
33#include <drm/amdgpu_drm.h>
34#include "amdgpu.h"
35
36#include "atom.h"
37#include "atom-bits.h"
38#include "atombios_encoders.h"
39#include "atombios_dp.h"
40#include "amdgpu_connectors.h"
41#include "amdgpu_atombios.h"
42#include <drm/drm_dp_helper.h>
43
44/* move these to drm_dp_helper.c/h */
45#define DP_LINK_CONFIGURATION_SIZE 9
46#define DP_DPCD_SIZE DP_RECEIVER_CAP_SIZE
47
48static const char *const voltage_names[] = {
49	"0.4V", "0.6V", "0.8V", "1.2V"
50};
51static const char *const pre_emph_names[] = {
52	"0dB", "3.5dB", "6dB", "9.5dB"
53};
54
55/***** amdgpu AUX functions *****/
56
57union aux_channel_transaction {
58	PROCESS_AUX_CHANNEL_TRANSACTION_PS_ALLOCATION v1;
59	PROCESS_AUX_CHANNEL_TRANSACTION_PARAMETERS_V2 v2;
60};
61
62static int amdgpu_atombios_dp_process_aux_ch(struct amdgpu_i2c_chan *chan,
63				      u8 *send, int send_bytes,
64				      u8 *recv, int recv_size,
65				      u8 delay, u8 *ack)
66{
67	struct drm_device *dev = chan->dev;
68	struct amdgpu_device *adev = dev->dev_private;
69	union aux_channel_transaction args;
70	int index = GetIndexIntoMasterTable(COMMAND, ProcessAuxChannelTransaction);
71	unsigned char *base;
72	int recv_bytes;
73	int r = 0;
74
75	memset(&args, 0, sizeof(args));
76
77	mutex_lock(&chan->mutex);
78
79	base = (unsigned char *)(adev->mode_info.atom_context->scratch + 1);
80
81	amdgpu_atombios_copy_swap(base, send, send_bytes, true);
82
83	args.v2.lpAuxRequest = cpu_to_le16((u16)(0 + 4));
84	args.v2.lpDataOut = cpu_to_le16((u16)(16 + 4));
85	args.v2.ucDataOutLen = 0;
86	args.v2.ucChannelID = chan->rec.i2c_id;
87	args.v2.ucDelay = delay / 10;
88	args.v2.ucHPD_ID = chan->rec.hpd;
89
90	amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args);
91
92	*ack = args.v2.ucReplyStatus;
93
94	/* timeout */
95	if (args.v2.ucReplyStatus == 1) {
96		r = -ETIMEDOUT;
97		goto done;
98	}
99
100	/* flags not zero */
101	if (args.v2.ucReplyStatus == 2) {
102		DRM_DEBUG_KMS("dp_aux_ch flags not zero\n");
103		r = -EIO;
104		goto done;
105	}
106
107	/* error */
108	if (args.v2.ucReplyStatus == 3) {
109		DRM_DEBUG_KMS("dp_aux_ch error\n");
110		r = -EIO;
111		goto done;
112	}
113
114	recv_bytes = args.v1.ucDataOutLen;
115	if (recv_bytes > recv_size)
116		recv_bytes = recv_size;
117
118	if (recv && recv_size)
119		amdgpu_atombios_copy_swap(recv, base + 16, recv_bytes, false);
120
121	r = recv_bytes;
122done:
123	mutex_unlock(&chan->mutex);
124
125	return r;
126}
127
128#define BARE_ADDRESS_SIZE 3
129#define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
130
131static ssize_t
132amdgpu_atombios_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
133{
134	struct amdgpu_i2c_chan *chan =
135		container_of(aux, struct amdgpu_i2c_chan, aux);
136	int ret;
137	u8 tx_buf[20];
138	size_t tx_size;
139	u8 ack, delay = 0;
140
141	if (WARN_ON(msg->size > 16))
142		return -E2BIG;
143
144	tx_buf[0] = msg->address & 0xff;
145	tx_buf[1] = msg->address >> 8;
146	tx_buf[2] = (msg->request << 4) |
147		((msg->address >> 16) & 0xf);
148	tx_buf[3] = msg->size ? (msg->size - 1) : 0;
149
150	switch (msg->request & ~DP_AUX_I2C_MOT) {
151	case DP_AUX_NATIVE_WRITE:
152	case DP_AUX_I2C_WRITE:
153		/* tx_size needs to be 4 even for bare address packets since the atom
154		 * table needs the info in tx_buf[3].
155		 */
156		tx_size = HEADER_SIZE + msg->size;
157		if (msg->size == 0)
158			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
159		else
160			tx_buf[3] |= tx_size << 4;
161		memcpy(tx_buf + HEADER_SIZE, msg->buffer, msg->size);
162		ret = amdgpu_atombios_dp_process_aux_ch(chan,
163						 tx_buf, tx_size, NULL, 0, delay, &ack);
164		if (ret >= 0)
165			/* Return payload size. */
166			ret = msg->size;
167		break;
168	case DP_AUX_NATIVE_READ:
169	case DP_AUX_I2C_READ:
170		/* tx_size needs to be 4 even for bare address packets since the atom
171		 * table needs the info in tx_buf[3].
172		 */
173		tx_size = HEADER_SIZE;
174		if (msg->size == 0)
175			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
176		else
177			tx_buf[3] |= tx_size << 4;
178		ret = amdgpu_atombios_dp_process_aux_ch(chan,
179						 tx_buf, tx_size, msg->buffer, msg->size, delay, &ack);
180		break;
181	default:
182		ret = -EINVAL;
183		break;
184	}
185
186	if (ret >= 0)
187		msg->reply = ack >> 4;
188
189	return ret;
190}
191
192void amdgpu_atombios_dp_aux_init(struct amdgpu_connector *amdgpu_connector)
193{
194	int ret;
195
196	amdgpu_connector->ddc_bus->rec.hpd = amdgpu_connector->hpd.hpd;
197	amdgpu_connector->ddc_bus->aux.dev = amdgpu_connector->base.kdev;
198	amdgpu_connector->ddc_bus->aux.transfer = amdgpu_atombios_dp_aux_transfer;
199	ret = drm_dp_aux_register(&amdgpu_connector->ddc_bus->aux);
200	if (!ret)
201		amdgpu_connector->ddc_bus->has_aux = true;
202
203	WARN(ret, "drm_dp_aux_register_i2c_bus() failed with error %d\n", ret);
204}
205
206/***** general DP utility functions *****/
207
208#define DP_VOLTAGE_MAX         DP_TRAIN_VOLTAGE_SWING_LEVEL_3
209#define DP_PRE_EMPHASIS_MAX    DP_TRAIN_PRE_EMPH_LEVEL_3
210
211static void amdgpu_atombios_dp_get_adjust_train(const u8 link_status[DP_LINK_STATUS_SIZE],
212						int lane_count,
213						u8 train_set[4])
214{
215	u8 v = 0;
216	u8 p = 0;
217	int lane;
218
219	for (lane = 0; lane < lane_count; lane++) {
220		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
221		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
222
223		DRM_DEBUG_KMS("requested signal parameters: lane %d voltage %s pre_emph %s\n",
224			  lane,
225			  voltage_names[this_v >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
226			  pre_emph_names[this_p >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
227
228		if (this_v > v)
229			v = this_v;
230		if (this_p > p)
231			p = this_p;
232	}
233
234	if (v >= DP_VOLTAGE_MAX)
235		v |= DP_TRAIN_MAX_SWING_REACHED;
236
237	if (p >= DP_PRE_EMPHASIS_MAX)
238		p |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
239
240	DRM_DEBUG_KMS("using signal parameters: voltage %s pre_emph %s\n",
241		  voltage_names[(v & DP_TRAIN_VOLTAGE_SWING_MASK) >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
242		  pre_emph_names[(p & DP_TRAIN_PRE_EMPHASIS_MASK) >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
243
244	for (lane = 0; lane < 4; lane++)
245		train_set[lane] = v | p;
246}
247
248/* convert bits per color to bits per pixel */
249/* get bpc from the EDID */
250static unsigned amdgpu_atombios_dp_convert_bpc_to_bpp(int bpc)
251{
252	if (bpc == 0)
253		return 24;
254	else
255		return bpc * 3;
256}
257
258/***** amdgpu specific DP functions *****/
259
260static int amdgpu_atombios_dp_get_dp_link_config(struct drm_connector *connector,
261						 const u8 dpcd[DP_DPCD_SIZE],
262						 unsigned pix_clock,
263						 unsigned *dp_lanes, unsigned *dp_rate)
264{
265	unsigned bpp =
266		amdgpu_atombios_dp_convert_bpc_to_bpp(amdgpu_connector_get_monitor_bpc(connector));
267	static const unsigned link_rates[3] = { 162000, 270000, 540000 };
268	unsigned max_link_rate = drm_dp_max_link_rate(dpcd);
269	unsigned max_lane_num = drm_dp_max_lane_count(dpcd);
270	unsigned lane_num, i, max_pix_clock;
271
272	if (amdgpu_connector_encoder_get_dp_bridge_encoder_id(connector) ==
273	    ENCODER_OBJECT_ID_NUTMEG) {
274		for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
275			max_pix_clock = (lane_num * 270000 * 8) / bpp;
276			if (max_pix_clock >= pix_clock) {
277				*dp_lanes = lane_num;
278				*dp_rate = 270000;
279				return 0;
280			}
281		}
282	} else {
283		for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) {
284			for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
285				max_pix_clock = (lane_num * link_rates[i] * 8) / bpp;
286				if (max_pix_clock >= pix_clock) {
287					*dp_lanes = lane_num;
288					*dp_rate = link_rates[i];
289					return 0;
290				}
291			}
292		}
293	}
294
295	return -EINVAL;
296}
297
298static u8 amdgpu_atombios_dp_encoder_service(struct amdgpu_device *adev,
299				      int action, int dp_clock,
300				      u8 ucconfig, u8 lane_num)
301{
302	DP_ENCODER_SERVICE_PARAMETERS args;
303	int index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
304
305	memset(&args, 0, sizeof(args));
306	args.ucLinkClock = dp_clock / 10;
307	args.ucConfig = ucconfig;
308	args.ucAction = action;
309	args.ucLaneNum = lane_num;
310	args.ucStatus = 0;
311
312	amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args);
313	return args.ucStatus;
314}
315
316u8 amdgpu_atombios_dp_get_sinktype(struct amdgpu_connector *amdgpu_connector)
317{
318	struct drm_device *dev = amdgpu_connector->base.dev;
319	struct amdgpu_device *adev = dev->dev_private;
320
321	return amdgpu_atombios_dp_encoder_service(adev, ATOM_DP_ACTION_GET_SINK_TYPE, 0,
322					   amdgpu_connector->ddc_bus->rec.i2c_id, 0);
323}
324
325static void amdgpu_atombios_dp_probe_oui(struct amdgpu_connector *amdgpu_connector)
326{
327	struct amdgpu_connector_atom_dig *dig_connector = amdgpu_connector->con_priv;
328	u8 buf[3];
329
330	if (!(dig_connector->dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
331		return;
332
333	if (drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux, DP_SINK_OUI, buf, 3) == 3)
334		DRM_DEBUG_KMS("Sink OUI: %02hhx%02hhx%02hhx\n",
335			      buf[0], buf[1], buf[2]);
336
337	if (drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux, DP_BRANCH_OUI, buf, 3) == 3)
338		DRM_DEBUG_KMS("Branch OUI: %02hhx%02hhx%02hhx\n",
339			      buf[0], buf[1], buf[2]);
340}
341
342int amdgpu_atombios_dp_get_dpcd(struct amdgpu_connector *amdgpu_connector)
343{
344	struct amdgpu_connector_atom_dig *dig_connector = amdgpu_connector->con_priv;
345	u8 msg[DP_DPCD_SIZE];
346	int ret;
347
348	ret = drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux, DP_DPCD_REV,
349			       msg, DP_DPCD_SIZE);
350	if (ret == DP_DPCD_SIZE) {
351		memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE);
352
353		DRM_DEBUG_KMS("DPCD: %*ph\n", (int)sizeof(dig_connector->dpcd),
354			      dig_connector->dpcd);
355
356		amdgpu_atombios_dp_probe_oui(amdgpu_connector);
357
358		return 0;
359	}
360
361	dig_connector->dpcd[0] = 0;
362	return -EINVAL;
363}
364
365int amdgpu_atombios_dp_get_panel_mode(struct drm_encoder *encoder,
366			       struct drm_connector *connector)
367{
368	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
369	int panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
370	u16 dp_bridge = amdgpu_connector_encoder_get_dp_bridge_encoder_id(connector);
371	u8 tmp;
372
373	if (!amdgpu_connector->con_priv)
374		return panel_mode;
375
376	if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
377		/* DP bridge chips */
378		if (drm_dp_dpcd_readb(&amdgpu_connector->ddc_bus->aux,
379				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
380			if (tmp & 1)
381				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
382			else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
383				 (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
384				panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
385			else
386				panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
387		}
388	} else if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
389		/* eDP */
390		if (drm_dp_dpcd_readb(&amdgpu_connector->ddc_bus->aux,
391				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
392			if (tmp & 1)
393				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
394		}
395	}
396
397	return panel_mode;
398}
399
400void amdgpu_atombios_dp_set_link_config(struct drm_connector *connector,
401				 const struct drm_display_mode *mode)
402{
403	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
404	struct amdgpu_connector_atom_dig *dig_connector;
405	int ret;
406
407	if (!amdgpu_connector->con_priv)
408		return;
409	dig_connector = amdgpu_connector->con_priv;
410
411	if ((dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) ||
412	    (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_eDP)) {
413		ret = amdgpu_atombios_dp_get_dp_link_config(connector, dig_connector->dpcd,
414							    mode->clock,
415							    &dig_connector->dp_lane_count,
416							    &dig_connector->dp_clock);
417		if (ret) {
418			dig_connector->dp_clock = 0;
419			dig_connector->dp_lane_count = 0;
420		}
421	}
422}
423
424int amdgpu_atombios_dp_mode_valid_helper(struct drm_connector *connector,
425				  struct drm_display_mode *mode)
426{
427	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
428	struct amdgpu_connector_atom_dig *dig_connector;
429	unsigned dp_lanes, dp_clock;
430	int ret;
431
432	if (!amdgpu_connector->con_priv)
433		return MODE_CLOCK_HIGH;
434	dig_connector = amdgpu_connector->con_priv;
435
436	ret = amdgpu_atombios_dp_get_dp_link_config(connector, dig_connector->dpcd,
437						    mode->clock, &dp_lanes, &dp_clock);
438	if (ret)
439		return MODE_CLOCK_HIGH;
440
441	if ((dp_clock == 540000) &&
442	    (!amdgpu_connector_is_dp12_capable(connector)))
443		return MODE_CLOCK_HIGH;
444
445	return MODE_OK;
446}
447
448bool amdgpu_atombios_dp_needs_link_train(struct amdgpu_connector *amdgpu_connector)
449{
450	u8 link_status[DP_LINK_STATUS_SIZE];
451	struct amdgpu_connector_atom_dig *dig = amdgpu_connector->con_priv;
452
453	if (drm_dp_dpcd_read_link_status(&amdgpu_connector->ddc_bus->aux, link_status)
454	    <= 0)
455		return false;
456	if (drm_dp_channel_eq_ok(link_status, dig->dp_lane_count))
457		return false;
458	return true;
459}
460
461void amdgpu_atombios_dp_set_rx_power_state(struct drm_connector *connector,
462				    u8 power_state)
463{
464	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
465	struct amdgpu_connector_atom_dig *dig_connector;
466
467	if (!amdgpu_connector->con_priv)
468		return;
469
470	dig_connector = amdgpu_connector->con_priv;
471
472	/* power up/down the sink */
473	if (dig_connector->dpcd[0] >= 0x11) {
474		drm_dp_dpcd_writeb(&amdgpu_connector->ddc_bus->aux,
475				   DP_SET_POWER, power_state);
476		usleep_range(1000, 2000);
477	}
478}
479
480struct amdgpu_atombios_dp_link_train_info {
481	struct amdgpu_device *adev;
482	struct drm_encoder *encoder;
483	struct drm_connector *connector;
484	int dp_clock;
485	int dp_lane_count;
486	bool tp3_supported;
487	u8 dpcd[DP_RECEIVER_CAP_SIZE];
488	u8 train_set[4];
489	u8 link_status[DP_LINK_STATUS_SIZE];
490	u8 tries;
491	struct drm_dp_aux *aux;
492};
493
494static void
495amdgpu_atombios_dp_update_vs_emph(struct amdgpu_atombios_dp_link_train_info *dp_info)
496{
497	/* set the initial vs/emph on the source */
498	amdgpu_atombios_encoder_setup_dig_transmitter(dp_info->encoder,
499					       ATOM_TRANSMITTER_ACTION_SETUP_VSEMPH,
500					       0, dp_info->train_set[0]); /* sets all lanes at once */
501
502	/* set the vs/emph on the sink */
503	drm_dp_dpcd_write(dp_info->aux, DP_TRAINING_LANE0_SET,
504			  dp_info->train_set, dp_info->dp_lane_count);
505}
506
507static void
508amdgpu_atombios_dp_set_tp(struct amdgpu_atombios_dp_link_train_info *dp_info, int tp)
509{
510	int rtp = 0;
511
512	/* set training pattern on the source */
513	switch (tp) {
514	case DP_TRAINING_PATTERN_1:
515		rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN1;
516		break;
517	case DP_TRAINING_PATTERN_2:
518		rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN2;
519		break;
520	case DP_TRAINING_PATTERN_3:
521		rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN3;
522			break;
523	}
524	amdgpu_atombios_encoder_setup_dig_encoder(dp_info->encoder, rtp, 0);
525
526	/* enable training pattern on the sink */
527	drm_dp_dpcd_writeb(dp_info->aux, DP_TRAINING_PATTERN_SET, tp);
528}
529
530static int
531amdgpu_atombios_dp_link_train_init(struct amdgpu_atombios_dp_link_train_info *dp_info)
532{
533	struct amdgpu_encoder *amdgpu_encoder = to_amdgpu_encoder(dp_info->encoder);
534	struct amdgpu_encoder_atom_dig *dig = amdgpu_encoder->enc_priv;
535	u8 tmp;
536
537	/* power up the sink */
538	amdgpu_atombios_dp_set_rx_power_state(dp_info->connector, DP_SET_POWER_D0);
539
540	/* possibly enable downspread on the sink */
541	if (dp_info->dpcd[3] & 0x1)
542		drm_dp_dpcd_writeb(dp_info->aux,
543				   DP_DOWNSPREAD_CTRL, DP_SPREAD_AMP_0_5);
544	else
545		drm_dp_dpcd_writeb(dp_info->aux,
546				   DP_DOWNSPREAD_CTRL, 0);
547
548	if (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)
549		drm_dp_dpcd_writeb(dp_info->aux, DP_EDP_CONFIGURATION_SET, 1);
550
551	/* set the lane count on the sink */
552	tmp = dp_info->dp_lane_count;
553	if (drm_dp_enhanced_frame_cap(dp_info->dpcd))
554		tmp |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
555	drm_dp_dpcd_writeb(dp_info->aux, DP_LANE_COUNT_SET, tmp);
556
557	/* set the link rate on the sink */
558	tmp = drm_dp_link_rate_to_bw_code(dp_info->dp_clock);
559	drm_dp_dpcd_writeb(dp_info->aux, DP_LINK_BW_SET, tmp);
560
561	/* start training on the source */
562	amdgpu_atombios_encoder_setup_dig_encoder(dp_info->encoder,
563					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_START, 0);
564
565	/* disable the training pattern on the sink */
566	drm_dp_dpcd_writeb(dp_info->aux,
567			   DP_TRAINING_PATTERN_SET,
568			   DP_TRAINING_PATTERN_DISABLE);
569
570	return 0;
571}
572
573static int
574amdgpu_atombios_dp_link_train_finish(struct amdgpu_atombios_dp_link_train_info *dp_info)
575{
576	udelay(400);
577
578	/* disable the training pattern on the sink */
579	drm_dp_dpcd_writeb(dp_info->aux,
580			   DP_TRAINING_PATTERN_SET,
581			   DP_TRAINING_PATTERN_DISABLE);
582
583	/* disable the training pattern on the source */
584	amdgpu_atombios_encoder_setup_dig_encoder(dp_info->encoder,
585					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_COMPLETE, 0);
586
587	return 0;
588}
589
590static int
591amdgpu_atombios_dp_link_train_cr(struct amdgpu_atombios_dp_link_train_info *dp_info)
592{
593	bool clock_recovery;
594	u8 voltage;
595	int i;
596
597	amdgpu_atombios_dp_set_tp(dp_info, DP_TRAINING_PATTERN_1);
598	memset(dp_info->train_set, 0, 4);
599	amdgpu_atombios_dp_update_vs_emph(dp_info);
600
601	udelay(400);
602
603	/* clock recovery loop */
604	clock_recovery = false;
605	dp_info->tries = 0;
606	voltage = 0xff;
607	while (1) {
608		drm_dp_link_train_clock_recovery_delay(dp_info->dpcd);
609
610		if (drm_dp_dpcd_read_link_status(dp_info->aux,
611						 dp_info->link_status) <= 0) {
612			DRM_ERROR("displayport link status failed\n");
613			break;
614		}
615
616		if (drm_dp_clock_recovery_ok(dp_info->link_status, dp_info->dp_lane_count)) {
617			clock_recovery = true;
618			break;
619		}
620
621		for (i = 0; i < dp_info->dp_lane_count; i++) {
622			if ((dp_info->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
623				break;
624		}
625		if (i == dp_info->dp_lane_count) {
626			DRM_ERROR("clock recovery reached max voltage\n");
627			break;
628		}
629
630		if ((dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
631			++dp_info->tries;
632			if (dp_info->tries == 5) {
633				DRM_ERROR("clock recovery tried 5 times\n");
634				break;
635			}
636		} else
637			dp_info->tries = 0;
638
639		voltage = dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
640
641		/* Compute new train_set as requested by sink */
642		amdgpu_atombios_dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count,
643					     dp_info->train_set);
644
645		amdgpu_atombios_dp_update_vs_emph(dp_info);
646	}
647	if (!clock_recovery) {
648		DRM_ERROR("clock recovery failed\n");
649		return -1;
650	} else {
651		DRM_DEBUG_KMS("clock recovery at voltage %d pre-emphasis %d\n",
652			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
653			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK) >>
654			  DP_TRAIN_PRE_EMPHASIS_SHIFT);
655		return 0;
656	}
657}
658
659static int
660amdgpu_atombios_dp_link_train_ce(struct amdgpu_atombios_dp_link_train_info *dp_info)
661{
662	bool channel_eq;
663
664	if (dp_info->tp3_supported)
665		amdgpu_atombios_dp_set_tp(dp_info, DP_TRAINING_PATTERN_3);
666	else
667		amdgpu_atombios_dp_set_tp(dp_info, DP_TRAINING_PATTERN_2);
668
669	/* channel equalization loop */
670	dp_info->tries = 0;
671	channel_eq = false;
672	while (1) {
673		drm_dp_link_train_channel_eq_delay(dp_info->dpcd);
674
675		if (drm_dp_dpcd_read_link_status(dp_info->aux,
676						 dp_info->link_status) <= 0) {
677			DRM_ERROR("displayport link status failed\n");
678			break;
679		}
680
681		if (drm_dp_channel_eq_ok(dp_info->link_status, dp_info->dp_lane_count)) {
682			channel_eq = true;
683			break;
684		}
685
686		/* Try 5 times */
687		if (dp_info->tries > 5) {
688			DRM_ERROR("channel eq failed: 5 tries\n");
689			break;
690		}
691
692		/* Compute new train_set as requested by sink */
693		amdgpu_atombios_dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count,
694					     dp_info->train_set);
695
696		amdgpu_atombios_dp_update_vs_emph(dp_info);
697		dp_info->tries++;
698	}
699
700	if (!channel_eq) {
701		DRM_ERROR("channel eq failed\n");
702		return -1;
703	} else {
704		DRM_DEBUG_KMS("channel eq at voltage %d pre-emphasis %d\n",
705			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
706			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK)
707			  >> DP_TRAIN_PRE_EMPHASIS_SHIFT);
708		return 0;
709	}
710}
711
712void amdgpu_atombios_dp_link_train(struct drm_encoder *encoder,
713			    struct drm_connector *connector)
714{
715	struct drm_device *dev = encoder->dev;
716	struct amdgpu_device *adev = dev->dev_private;
717	struct amdgpu_encoder *amdgpu_encoder = to_amdgpu_encoder(encoder);
718	struct amdgpu_connector *amdgpu_connector;
719	struct amdgpu_connector_atom_dig *dig_connector;
720	struct amdgpu_atombios_dp_link_train_info dp_info;
721	u8 tmp;
722
723	if (!amdgpu_encoder->enc_priv)
724		return;
725
726	amdgpu_connector = to_amdgpu_connector(connector);
727	if (!amdgpu_connector->con_priv)
728		return;
729	dig_connector = amdgpu_connector->con_priv;
730
731	if ((dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_DISPLAYPORT) &&
732	    (dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_eDP))
733		return;
734
735	if (drm_dp_dpcd_readb(&amdgpu_connector->ddc_bus->aux, DP_MAX_LANE_COUNT, &tmp)
736	    == 1) {
737		if (tmp & DP_TPS3_SUPPORTED)
738			dp_info.tp3_supported = true;
739		else
740			dp_info.tp3_supported = false;
741	} else {
742		dp_info.tp3_supported = false;
743	}
744
745	memcpy(dp_info.dpcd, dig_connector->dpcd, DP_RECEIVER_CAP_SIZE);
746	dp_info.adev = adev;
747	dp_info.encoder = encoder;
748	dp_info.connector = connector;
749	dp_info.dp_lane_count = dig_connector->dp_lane_count;
750	dp_info.dp_clock = dig_connector->dp_clock;
751	dp_info.aux = &amdgpu_connector->ddc_bus->aux;
752
753	if (amdgpu_atombios_dp_link_train_init(&dp_info))
754		goto done;
755	if (amdgpu_atombios_dp_link_train_cr(&dp_info))
756		goto done;
757	if (amdgpu_atombios_dp_link_train_ce(&dp_info))
758		goto done;
759done:
760	if (amdgpu_atombios_dp_link_train_finish(&dp_info))
761		return;
762}
763