1/*
2 * Copyright 2007-8 Advanced Micro Devices, Inc.
3 * Copyright 2008 Red Hat Inc.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21 * OTHER DEALINGS IN THE SOFTWARE.
22 *
23 * Authors: Dave Airlie
24 *          Alex Deucher
25 *          Jerome Glisse
26 */
27
28#include <drm/amdgpu_drm.h>
29#include <drm/display/drm_dp_helper.h>
30
31#include "amdgpu.h"
32
33#include "atom.h"
34#include "atom-bits.h"
35#include "atombios_encoders.h"
36#include "atombios_dp.h"
37#include "amdgpu_connectors.h"
38#include "amdgpu_atombios.h"
39
40/* move these to drm_dp_helper.c/h */
41#define DP_LINK_CONFIGURATION_SIZE 9
42#define DP_DPCD_SIZE DP_RECEIVER_CAP_SIZE
43
44static char *voltage_names[] = {
45	"0.4V", "0.6V", "0.8V", "1.2V"
46};
47static char *pre_emph_names[] = {
48	"0dB", "3.5dB", "6dB", "9.5dB"
49};
50
51/***** amdgpu AUX functions *****/
52
53union aux_channel_transaction {
54	PROCESS_AUX_CHANNEL_TRANSACTION_PS_ALLOCATION v1;
55	PROCESS_AUX_CHANNEL_TRANSACTION_PARAMETERS_V2 v2;
56};
57
58static int amdgpu_atombios_dp_process_aux_ch(struct amdgpu_i2c_chan *chan,
59				      u8 *send, int send_bytes,
60				      u8 *recv, int recv_size,
61				      u8 delay, u8 *ack)
62{
63	struct drm_device *dev = chan->dev;
64	struct amdgpu_device *adev = drm_to_adev(dev);
65	union aux_channel_transaction args;
66	int index = GetIndexIntoMasterTable(COMMAND, ProcessAuxChannelTransaction);
67	unsigned char *base;
68	int recv_bytes;
69	int r = 0;
70
71	memset(&args, 0, sizeof(args));
72
73	mutex_lock(&chan->mutex);
74
75	base = (unsigned char *)(adev->mode_info.atom_context->scratch + 1);
76
77	amdgpu_atombios_copy_swap(base, send, send_bytes, true);
78
79	args.v2.lpAuxRequest = cpu_to_le16((u16)(0 + 4));
80	args.v2.lpDataOut = cpu_to_le16((u16)(16 + 4));
81	args.v2.ucDataOutLen = 0;
82	args.v2.ucChannelID = chan->rec.i2c_id;
83	args.v2.ucDelay = delay / 10;
84	args.v2.ucHPD_ID = chan->rec.hpd;
85
86	amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args);
87
88	*ack = args.v2.ucReplyStatus;
89
90	/* timeout */
91	if (args.v2.ucReplyStatus == 1) {
92		r = -ETIMEDOUT;
93		goto done;
94	}
95
96	/* flags not zero */
97	if (args.v2.ucReplyStatus == 2) {
98		DRM_DEBUG_KMS("dp_aux_ch flags not zero\n");
99		r = -EIO;
100		goto done;
101	}
102
103	/* error */
104	if (args.v2.ucReplyStatus == 3) {
105		DRM_DEBUG_KMS("dp_aux_ch error\n");
106		r = -EIO;
107		goto done;
108	}
109
110	recv_bytes = args.v1.ucDataOutLen;
111	if (recv_bytes > recv_size)
112		recv_bytes = recv_size;
113
114	if (recv && recv_size)
115		amdgpu_atombios_copy_swap(recv, base + 16, recv_bytes, false);
116
117	r = recv_bytes;
118done:
119	mutex_unlock(&chan->mutex);
120
121	return r;
122}
123
124#define BARE_ADDRESS_SIZE 3
125#define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
126
127static ssize_t
128amdgpu_atombios_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
129{
130	struct amdgpu_i2c_chan *chan =
131		container_of(aux, struct amdgpu_i2c_chan, aux);
132	int ret;
133	u8 tx_buf[20];
134	size_t tx_size;
135	u8 ack, delay = 0;
136
137	if (WARN_ON(msg->size > 16))
138		return -E2BIG;
139
140	tx_buf[0] = msg->address & 0xff;
141	tx_buf[1] = msg->address >> 8;
142	tx_buf[2] = (msg->request << 4) |
143		((msg->address >> 16) & 0xf);
144	tx_buf[3] = msg->size ? (msg->size - 1) : 0;
145
146	switch (msg->request & ~DP_AUX_I2C_MOT) {
147	case DP_AUX_NATIVE_WRITE:
148	case DP_AUX_I2C_WRITE:
149		/* tx_size needs to be 4 even for bare address packets since the atom
150		 * table needs the info in tx_buf[3].
151		 */
152		tx_size = HEADER_SIZE + msg->size;
153		if (msg->size == 0)
154			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
155		else
156			tx_buf[3] |= tx_size << 4;
157		memcpy(tx_buf + HEADER_SIZE, msg->buffer, msg->size);
158		ret = amdgpu_atombios_dp_process_aux_ch(chan,
159						 tx_buf, tx_size, NULL, 0, delay, &ack);
160		if (ret >= 0)
161			/* Return payload size. */
162			ret = msg->size;
163		break;
164	case DP_AUX_NATIVE_READ:
165	case DP_AUX_I2C_READ:
166		/* tx_size needs to be 4 even for bare address packets since the atom
167		 * table needs the info in tx_buf[3].
168		 */
169		tx_size = HEADER_SIZE;
170		if (msg->size == 0)
171			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
172		else
173			tx_buf[3] |= tx_size << 4;
174		ret = amdgpu_atombios_dp_process_aux_ch(chan,
175						 tx_buf, tx_size, msg->buffer, msg->size, delay, &ack);
176		break;
177	default:
178		ret = -EINVAL;
179		break;
180	}
181
182	if (ret >= 0)
183		msg->reply = ack >> 4;
184
185	return ret;
186}
187
188void amdgpu_atombios_dp_aux_init(struct amdgpu_connector *amdgpu_connector)
189{
190	amdgpu_connector->ddc_bus->rec.hpd = amdgpu_connector->hpd.hpd;
191	amdgpu_connector->ddc_bus->aux.transfer = amdgpu_atombios_dp_aux_transfer;
192	amdgpu_connector->ddc_bus->aux.drm_dev = amdgpu_connector->base.dev;
193
194	drm_dp_aux_init(&amdgpu_connector->ddc_bus->aux);
195	amdgpu_connector->ddc_bus->has_aux = true;
196}
197
198/***** general DP utility functions *****/
199
200#define DP_VOLTAGE_MAX         DP_TRAIN_VOLTAGE_SWING_LEVEL_3
201#define DP_PRE_EMPHASIS_MAX    DP_TRAIN_PRE_EMPH_LEVEL_3
202
203static void amdgpu_atombios_dp_get_adjust_train(const u8 link_status[DP_LINK_STATUS_SIZE],
204						int lane_count,
205						u8 train_set[4])
206{
207	u8 v = 0;
208	u8 p = 0;
209	int lane;
210
211	for (lane = 0; lane < lane_count; lane++) {
212		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
213		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
214
215		DRM_DEBUG_KMS("requested signal parameters: lane %d voltage %s pre_emph %s\n",
216			  lane,
217			  voltage_names[this_v >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
218			  pre_emph_names[this_p >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
219
220		if (this_v > v)
221			v = this_v;
222		if (this_p > p)
223			p = this_p;
224	}
225
226	if (v >= DP_VOLTAGE_MAX)
227		v |= DP_TRAIN_MAX_SWING_REACHED;
228
229	if (p >= DP_PRE_EMPHASIS_MAX)
230		p |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
231
232	DRM_DEBUG_KMS("using signal parameters: voltage %s pre_emph %s\n",
233		  voltage_names[(v & DP_TRAIN_VOLTAGE_SWING_MASK) >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
234		  pre_emph_names[(p & DP_TRAIN_PRE_EMPHASIS_MASK) >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
235
236	for (lane = 0; lane < 4; lane++)
237		train_set[lane] = v | p;
238}
239
240/* convert bits per color to bits per pixel */
241/* get bpc from the EDID */
242static unsigned amdgpu_atombios_dp_convert_bpc_to_bpp(int bpc)
243{
244	if (bpc == 0)
245		return 24;
246	else
247		return bpc * 3;
248}
249
250/***** amdgpu specific DP functions *****/
251
252static int amdgpu_atombios_dp_get_dp_link_config(struct drm_connector *connector,
253						 const u8 dpcd[DP_DPCD_SIZE],
254						 unsigned pix_clock,
255						 unsigned *dp_lanes, unsigned *dp_rate)
256{
257	unsigned bpp =
258		amdgpu_atombios_dp_convert_bpc_to_bpp(amdgpu_connector_get_monitor_bpc(connector));
259	static const unsigned link_rates[3] = { 162000, 270000, 540000 };
260	unsigned max_link_rate = drm_dp_max_link_rate(dpcd);
261	unsigned max_lane_num = drm_dp_max_lane_count(dpcd);
262	unsigned lane_num, i, max_pix_clock;
263
264	if (amdgpu_connector_encoder_get_dp_bridge_encoder_id(connector) ==
265	    ENCODER_OBJECT_ID_NUTMEG) {
266		for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
267			max_pix_clock = (lane_num * 270000 * 8) / bpp;
268			if (max_pix_clock >= pix_clock) {
269				*dp_lanes = lane_num;
270				*dp_rate = 270000;
271				return 0;
272			}
273		}
274	} else {
275		for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) {
276			for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
277				max_pix_clock = (lane_num * link_rates[i] * 8) / bpp;
278				if (max_pix_clock >= pix_clock) {
279					*dp_lanes = lane_num;
280					*dp_rate = link_rates[i];
281					return 0;
282				}
283			}
284		}
285	}
286
287	return -EINVAL;
288}
289
290static u8 amdgpu_atombios_dp_encoder_service(struct amdgpu_device *adev,
291				      int action, int dp_clock,
292				      u8 ucconfig, u8 lane_num)
293{
294	DP_ENCODER_SERVICE_PARAMETERS args;
295	int index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
296
297	memset(&args, 0, sizeof(args));
298	args.ucLinkClock = dp_clock / 10;
299	args.ucConfig = ucconfig;
300	args.ucAction = action;
301	args.ucLaneNum = lane_num;
302	args.ucStatus = 0;
303
304	amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args);
305	return args.ucStatus;
306}
307
308u8 amdgpu_atombios_dp_get_sinktype(struct amdgpu_connector *amdgpu_connector)
309{
310	struct drm_device *dev = amdgpu_connector->base.dev;
311	struct amdgpu_device *adev = drm_to_adev(dev);
312
313	return amdgpu_atombios_dp_encoder_service(adev, ATOM_DP_ACTION_GET_SINK_TYPE, 0,
314					   amdgpu_connector->ddc_bus->rec.i2c_id, 0);
315}
316
317static void amdgpu_atombios_dp_probe_oui(struct amdgpu_connector *amdgpu_connector)
318{
319	struct amdgpu_connector_atom_dig *dig_connector = amdgpu_connector->con_priv;
320	u8 buf[3];
321
322	if (!(dig_connector->dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
323		return;
324
325	if (drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux, DP_SINK_OUI, buf, 3) == 3)
326		DRM_DEBUG_KMS("Sink OUI: %02hx%02hx%02hx\n",
327			      buf[0], buf[1], buf[2]);
328
329	if (drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux, DP_BRANCH_OUI, buf, 3) == 3)
330		DRM_DEBUG_KMS("Branch OUI: %02hx%02hx%02hx\n",
331			      buf[0], buf[1], buf[2]);
332}
333
334static void amdgpu_atombios_dp_ds_ports(struct amdgpu_connector *amdgpu_connector)
335{
336	struct amdgpu_connector_atom_dig *dig_connector = amdgpu_connector->con_priv;
337	int ret;
338
339	if (dig_connector->dpcd[DP_DPCD_REV] > 0x10) {
340		ret = drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux,
341				       DP_DOWNSTREAM_PORT_0,
342				       dig_connector->downstream_ports,
343				       DP_MAX_DOWNSTREAM_PORTS);
344		if (ret)
345			memset(dig_connector->downstream_ports, 0,
346			       DP_MAX_DOWNSTREAM_PORTS);
347	}
348}
349
350int amdgpu_atombios_dp_get_dpcd(struct amdgpu_connector *amdgpu_connector)
351{
352	struct amdgpu_connector_atom_dig *dig_connector = amdgpu_connector->con_priv;
353	u8 msg[DP_DPCD_SIZE];
354	int ret;
355
356	ret = drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux, DP_DPCD_REV,
357			       msg, DP_DPCD_SIZE);
358	if (ret == DP_DPCD_SIZE) {
359		memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE);
360
361		DRM_DEBUG_KMS("DPCD: %*ph\n", (int)sizeof(dig_connector->dpcd),
362			      dig_connector->dpcd);
363
364		amdgpu_atombios_dp_probe_oui(amdgpu_connector);
365		amdgpu_atombios_dp_ds_ports(amdgpu_connector);
366		return 0;
367	}
368
369	dig_connector->dpcd[0] = 0;
370	return -EINVAL;
371}
372
373int amdgpu_atombios_dp_get_panel_mode(struct drm_encoder *encoder,
374			       struct drm_connector *connector)
375{
376	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
377	int panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
378	u16 dp_bridge = amdgpu_connector_encoder_get_dp_bridge_encoder_id(connector);
379	u8 tmp;
380
381	if (!amdgpu_connector->con_priv)
382		return panel_mode;
383
384	if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
385		/* DP bridge chips */
386		if (drm_dp_dpcd_readb(&amdgpu_connector->ddc_bus->aux,
387				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
388			if (tmp & 1)
389				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
390			else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
391				 (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
392				panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
393			else
394				panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
395		}
396	} else if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
397		/* eDP */
398		if (drm_dp_dpcd_readb(&amdgpu_connector->ddc_bus->aux,
399				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
400			if (tmp & 1)
401				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
402		}
403	}
404
405	return panel_mode;
406}
407
408void amdgpu_atombios_dp_set_link_config(struct drm_connector *connector,
409				 const struct drm_display_mode *mode)
410{
411	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
412	struct amdgpu_connector_atom_dig *dig_connector;
413	int ret;
414
415	if (!amdgpu_connector->con_priv)
416		return;
417	dig_connector = amdgpu_connector->con_priv;
418
419	if ((dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) ||
420	    (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_eDP)) {
421		ret = amdgpu_atombios_dp_get_dp_link_config(connector, dig_connector->dpcd,
422							    mode->clock,
423							    &dig_connector->dp_lane_count,
424							    &dig_connector->dp_clock);
425		if (ret) {
426			dig_connector->dp_clock = 0;
427			dig_connector->dp_lane_count = 0;
428		}
429	}
430}
431
432int amdgpu_atombios_dp_mode_valid_helper(struct drm_connector *connector,
433				  struct drm_display_mode *mode)
434{
435	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
436	struct amdgpu_connector_atom_dig *dig_connector;
437	unsigned dp_lanes, dp_clock;
438	int ret;
439
440	if (!amdgpu_connector->con_priv)
441		return MODE_CLOCK_HIGH;
442	dig_connector = amdgpu_connector->con_priv;
443
444	ret = amdgpu_atombios_dp_get_dp_link_config(connector, dig_connector->dpcd,
445						    mode->clock, &dp_lanes, &dp_clock);
446	if (ret)
447		return MODE_CLOCK_HIGH;
448
449	if ((dp_clock == 540000) &&
450	    (!amdgpu_connector_is_dp12_capable(connector)))
451		return MODE_CLOCK_HIGH;
452
453	return MODE_OK;
454}
455
456bool amdgpu_atombios_dp_needs_link_train(struct amdgpu_connector *amdgpu_connector)
457{
458	u8 link_status[DP_LINK_STATUS_SIZE];
459	struct amdgpu_connector_atom_dig *dig = amdgpu_connector->con_priv;
460
461	if (drm_dp_dpcd_read_link_status(&amdgpu_connector->ddc_bus->aux, link_status)
462	    <= 0)
463		return false;
464	if (drm_dp_channel_eq_ok(link_status, dig->dp_lane_count))
465		return false;
466	return true;
467}
468
469void amdgpu_atombios_dp_set_rx_power_state(struct drm_connector *connector,
470				    u8 power_state)
471{
472	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
473	struct amdgpu_connector_atom_dig *dig_connector;
474
475	if (!amdgpu_connector->con_priv)
476		return;
477
478	dig_connector = amdgpu_connector->con_priv;
479
480	/* power up/down the sink */
481	if (dig_connector->dpcd[0] >= 0x11) {
482		drm_dp_dpcd_writeb(&amdgpu_connector->ddc_bus->aux,
483				   DP_SET_POWER, power_state);
484		usleep_range(1000, 2000);
485	}
486}
487
488struct amdgpu_atombios_dp_link_train_info {
489	struct amdgpu_device *adev;
490	struct drm_encoder *encoder;
491	struct drm_connector *connector;
492	int dp_clock;
493	int dp_lane_count;
494	bool tp3_supported;
495	u8 dpcd[DP_RECEIVER_CAP_SIZE];
496	u8 train_set[4];
497	u8 link_status[DP_LINK_STATUS_SIZE];
498	u8 tries;
499	struct drm_dp_aux *aux;
500};
501
502static void
503amdgpu_atombios_dp_update_vs_emph(struct amdgpu_atombios_dp_link_train_info *dp_info)
504{
505	/* set the initial vs/emph on the source */
506	amdgpu_atombios_encoder_setup_dig_transmitter(dp_info->encoder,
507					       ATOM_TRANSMITTER_ACTION_SETUP_VSEMPH,
508					       0, dp_info->train_set[0]); /* sets all lanes at once */
509
510	/* set the vs/emph on the sink */
511	drm_dp_dpcd_write(dp_info->aux, DP_TRAINING_LANE0_SET,
512			  dp_info->train_set, dp_info->dp_lane_count);
513}
514
515static void
516amdgpu_atombios_dp_set_tp(struct amdgpu_atombios_dp_link_train_info *dp_info, int tp)
517{
518	int rtp = 0;
519
520	/* set training pattern on the source */
521	switch (tp) {
522	case DP_TRAINING_PATTERN_1:
523		rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN1;
524		break;
525	case DP_TRAINING_PATTERN_2:
526		rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN2;
527		break;
528	case DP_TRAINING_PATTERN_3:
529		rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN3;
530			break;
531	}
532	amdgpu_atombios_encoder_setup_dig_encoder(dp_info->encoder, rtp, 0);
533
534	/* enable training pattern on the sink */
535	drm_dp_dpcd_writeb(dp_info->aux, DP_TRAINING_PATTERN_SET, tp);
536}
537
538static int
539amdgpu_atombios_dp_link_train_init(struct amdgpu_atombios_dp_link_train_info *dp_info)
540{
541	struct amdgpu_encoder *amdgpu_encoder = to_amdgpu_encoder(dp_info->encoder);
542	struct amdgpu_encoder_atom_dig *dig = amdgpu_encoder->enc_priv;
543	u8 tmp;
544
545	/* power up the sink */
546	amdgpu_atombios_dp_set_rx_power_state(dp_info->connector, DP_SET_POWER_D0);
547
548	/* possibly enable downspread on the sink */
549	if (dp_info->dpcd[3] & 0x1)
550		drm_dp_dpcd_writeb(dp_info->aux,
551				   DP_DOWNSPREAD_CTRL, DP_SPREAD_AMP_0_5);
552	else
553		drm_dp_dpcd_writeb(dp_info->aux,
554				   DP_DOWNSPREAD_CTRL, 0);
555
556	if (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)
557		drm_dp_dpcd_writeb(dp_info->aux, DP_EDP_CONFIGURATION_SET, 1);
558
559	/* set the lane count on the sink */
560	tmp = dp_info->dp_lane_count;
561	if (drm_dp_enhanced_frame_cap(dp_info->dpcd))
562		tmp |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
563	drm_dp_dpcd_writeb(dp_info->aux, DP_LANE_COUNT_SET, tmp);
564
565	/* set the link rate on the sink */
566	tmp = drm_dp_link_rate_to_bw_code(dp_info->dp_clock);
567	drm_dp_dpcd_writeb(dp_info->aux, DP_LINK_BW_SET, tmp);
568
569	/* start training on the source */
570	amdgpu_atombios_encoder_setup_dig_encoder(dp_info->encoder,
571					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_START, 0);
572
573	/* disable the training pattern on the sink */
574	drm_dp_dpcd_writeb(dp_info->aux,
575			   DP_TRAINING_PATTERN_SET,
576			   DP_TRAINING_PATTERN_DISABLE);
577
578	return 0;
579}
580
581static int
582amdgpu_atombios_dp_link_train_finish(struct amdgpu_atombios_dp_link_train_info *dp_info)
583{
584	udelay(400);
585
586	/* disable the training pattern on the sink */
587	drm_dp_dpcd_writeb(dp_info->aux,
588			   DP_TRAINING_PATTERN_SET,
589			   DP_TRAINING_PATTERN_DISABLE);
590
591	/* disable the training pattern on the source */
592	amdgpu_atombios_encoder_setup_dig_encoder(dp_info->encoder,
593					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_COMPLETE, 0);
594
595	return 0;
596}
597
598static int
599amdgpu_atombios_dp_link_train_cr(struct amdgpu_atombios_dp_link_train_info *dp_info)
600{
601	bool clock_recovery;
602	u8 voltage;
603	int i;
604
605	amdgpu_atombios_dp_set_tp(dp_info, DP_TRAINING_PATTERN_1);
606	memset(dp_info->train_set, 0, 4);
607	amdgpu_atombios_dp_update_vs_emph(dp_info);
608
609	udelay(400);
610
611	/* clock recovery loop */
612	clock_recovery = false;
613	dp_info->tries = 0;
614	voltage = 0xff;
615	while (1) {
616		drm_dp_link_train_clock_recovery_delay(dp_info->aux, dp_info->dpcd);
617
618		if (drm_dp_dpcd_read_link_status(dp_info->aux,
619						 dp_info->link_status) <= 0) {
620			DRM_ERROR("displayport link status failed\n");
621			break;
622		}
623
624		if (drm_dp_clock_recovery_ok(dp_info->link_status, dp_info->dp_lane_count)) {
625			clock_recovery = true;
626			break;
627		}
628
629		for (i = 0; i < dp_info->dp_lane_count; i++) {
630			if ((dp_info->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
631				break;
632		}
633		if (i == dp_info->dp_lane_count) {
634			DRM_ERROR("clock recovery reached max voltage\n");
635			break;
636		}
637
638		if ((dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
639			++dp_info->tries;
640			if (dp_info->tries == 5) {
641				DRM_ERROR("clock recovery tried 5 times\n");
642				break;
643			}
644		} else
645			dp_info->tries = 0;
646
647		voltage = dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
648
649		/* Compute new train_set as requested by sink */
650		amdgpu_atombios_dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count,
651					     dp_info->train_set);
652
653		amdgpu_atombios_dp_update_vs_emph(dp_info);
654	}
655	if (!clock_recovery) {
656		DRM_ERROR("clock recovery failed\n");
657		return -1;
658	} else {
659		DRM_DEBUG_KMS("clock recovery at voltage %d pre-emphasis %d\n",
660			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
661			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK) >>
662			  DP_TRAIN_PRE_EMPHASIS_SHIFT);
663		return 0;
664	}
665}
666
667static int
668amdgpu_atombios_dp_link_train_ce(struct amdgpu_atombios_dp_link_train_info *dp_info)
669{
670	bool channel_eq;
671
672	if (dp_info->tp3_supported)
673		amdgpu_atombios_dp_set_tp(dp_info, DP_TRAINING_PATTERN_3);
674	else
675		amdgpu_atombios_dp_set_tp(dp_info, DP_TRAINING_PATTERN_2);
676
677	/* channel equalization loop */
678	dp_info->tries = 0;
679	channel_eq = false;
680	while (1) {
681		drm_dp_link_train_channel_eq_delay(dp_info->aux, dp_info->dpcd);
682
683		if (drm_dp_dpcd_read_link_status(dp_info->aux,
684						 dp_info->link_status) <= 0) {
685			DRM_ERROR("displayport link status failed\n");
686			break;
687		}
688
689		if (drm_dp_channel_eq_ok(dp_info->link_status, dp_info->dp_lane_count)) {
690			channel_eq = true;
691			break;
692		}
693
694		/* Try 5 times */
695		if (dp_info->tries > 5) {
696			DRM_ERROR("channel eq failed: 5 tries\n");
697			break;
698		}
699
700		/* Compute new train_set as requested by sink */
701		amdgpu_atombios_dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count,
702					     dp_info->train_set);
703
704		amdgpu_atombios_dp_update_vs_emph(dp_info);
705		dp_info->tries++;
706	}
707
708	if (!channel_eq) {
709		DRM_ERROR("channel eq failed\n");
710		return -1;
711	} else {
712		DRM_DEBUG_KMS("channel eq at voltage %d pre-emphasis %d\n",
713			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
714			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK)
715			  >> DP_TRAIN_PRE_EMPHASIS_SHIFT);
716		return 0;
717	}
718}
719
720void amdgpu_atombios_dp_link_train(struct drm_encoder *encoder,
721			    struct drm_connector *connector)
722{
723	struct drm_device *dev = encoder->dev;
724	struct amdgpu_device *adev = drm_to_adev(dev);
725	struct amdgpu_encoder *amdgpu_encoder = to_amdgpu_encoder(encoder);
726	struct amdgpu_connector *amdgpu_connector;
727	struct amdgpu_connector_atom_dig *dig_connector;
728	struct amdgpu_atombios_dp_link_train_info dp_info;
729	u8 tmp;
730
731	if (!amdgpu_encoder->enc_priv)
732		return;
733
734	amdgpu_connector = to_amdgpu_connector(connector);
735	if (!amdgpu_connector->con_priv)
736		return;
737	dig_connector = amdgpu_connector->con_priv;
738
739	if ((dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_DISPLAYPORT) &&
740	    (dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_eDP))
741		return;
742
743	if (drm_dp_dpcd_readb(&amdgpu_connector->ddc_bus->aux, DP_MAX_LANE_COUNT, &tmp)
744	    == 1) {
745		if (tmp & DP_TPS3_SUPPORTED)
746			dp_info.tp3_supported = true;
747		else
748			dp_info.tp3_supported = false;
749	} else {
750		dp_info.tp3_supported = false;
751	}
752
753	memcpy(dp_info.dpcd, dig_connector->dpcd, DP_RECEIVER_CAP_SIZE);
754	dp_info.adev = adev;
755	dp_info.encoder = encoder;
756	dp_info.connector = connector;
757	dp_info.dp_lane_count = dig_connector->dp_lane_count;
758	dp_info.dp_clock = dig_connector->dp_clock;
759	dp_info.aux = &amdgpu_connector->ddc_bus->aux;
760
761	if (amdgpu_atombios_dp_link_train_init(&dp_info))
762		goto done;
763	if (amdgpu_atombios_dp_link_train_cr(&dp_info))
764		goto done;
765	if (amdgpu_atombios_dp_link_train_ce(&dp_info))
766		goto done;
767done:
768	if (amdgpu_atombios_dp_link_train_finish(&dp_info))
769		return;
770}
771