xref: /linux/drivers/gpu/drm/radeon/atombios_dp.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
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 #include <drm/drmP.h>
28 #include <drm/radeon_drm.h>
29 #include "radeon.h"
30 
31 #include "atom.h"
32 #include "atom-bits.h"
33 #include <drm/drm_dp_helper.h>
34 
35 /* move these to drm_dp_helper.c/h */
36 #define DP_LINK_CONFIGURATION_SIZE 9
37 #define DP_DPCD_SIZE DP_RECEIVER_CAP_SIZE
38 
39 static char *voltage_names[] = {
40         "0.4V", "0.6V", "0.8V", "1.2V"
41 };
42 static char *pre_emph_names[] = {
43         "0dB", "3.5dB", "6dB", "9.5dB"
44 };
45 
46 /***** radeon AUX functions *****/
47 
48 /* Atom needs data in little endian format
49  * so swap as appropriate when copying data to
50  * or from atom. Note that atom operates on
51  * dw units.
52  */
53 void radeon_atom_copy_swap(u8 *dst, u8 *src, u8 num_bytes, bool to_le)
54 {
55 #ifdef __BIG_ENDIAN
56 	u8 src_tmp[20], dst_tmp[20]; /* used for byteswapping */
57 	u32 *dst32, *src32;
58 	int i;
59 
60 	memcpy(src_tmp, src, num_bytes);
61 	src32 = (u32 *)src_tmp;
62 	dst32 = (u32 *)dst_tmp;
63 	if (to_le) {
64 		for (i = 0; i < ((num_bytes + 3) / 4); i++)
65 			dst32[i] = cpu_to_le32(src32[i]);
66 		memcpy(dst, dst_tmp, num_bytes);
67 	} else {
68 		u8 dws = num_bytes & ~3;
69 		for (i = 0; i < ((num_bytes + 3) / 4); i++)
70 			dst32[i] = le32_to_cpu(src32[i]);
71 		memcpy(dst, dst_tmp, dws);
72 		if (num_bytes % 4) {
73 			for (i = 0; i < (num_bytes % 4); i++)
74 				dst[dws+i] = dst_tmp[dws+i];
75 		}
76 	}
77 #else
78 	memcpy(dst, src, num_bytes);
79 #endif
80 }
81 
82 union aux_channel_transaction {
83 	PROCESS_AUX_CHANNEL_TRANSACTION_PS_ALLOCATION v1;
84 	PROCESS_AUX_CHANNEL_TRANSACTION_PARAMETERS_V2 v2;
85 };
86 
87 static int radeon_process_aux_ch(struct radeon_i2c_chan *chan,
88 				 u8 *send, int send_bytes,
89 				 u8 *recv, int recv_size,
90 				 u8 delay, u8 *ack)
91 {
92 	struct drm_device *dev = chan->dev;
93 	struct radeon_device *rdev = dev->dev_private;
94 	union aux_channel_transaction args;
95 	int index = GetIndexIntoMasterTable(COMMAND, ProcessAuxChannelTransaction);
96 	unsigned char *base;
97 	int recv_bytes;
98 	int r = 0;
99 
100 	memset(&args, 0, sizeof(args));
101 
102 	mutex_lock(&chan->mutex);
103 
104 	base = (unsigned char *)(rdev->mode_info.atom_context->scratch + 1);
105 
106 	radeon_atom_copy_swap(base, send, send_bytes, true);
107 
108 	args.v1.lpAuxRequest = cpu_to_le16((u16)(0 + 4));
109 	args.v1.lpDataOut = cpu_to_le16((u16)(16 + 4));
110 	args.v1.ucDataOutLen = 0;
111 	args.v1.ucChannelID = chan->rec.i2c_id;
112 	args.v1.ucDelay = delay / 10;
113 	if (ASIC_IS_DCE4(rdev))
114 		args.v2.ucHPD_ID = chan->rec.hpd;
115 
116 	atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
117 
118 	*ack = args.v1.ucReplyStatus;
119 
120 	/* timeout */
121 	if (args.v1.ucReplyStatus == 1) {
122 		DRM_DEBUG_KMS("dp_aux_ch timeout\n");
123 		r = -ETIMEDOUT;
124 		goto done;
125 	}
126 
127 	/* flags not zero */
128 	if (args.v1.ucReplyStatus == 2) {
129 		DRM_DEBUG_KMS("dp_aux_ch flags not zero\n");
130 		r = -EIO;
131 		goto done;
132 	}
133 
134 	/* error */
135 	if (args.v1.ucReplyStatus == 3) {
136 		DRM_DEBUG_KMS("dp_aux_ch error\n");
137 		r = -EIO;
138 		goto done;
139 	}
140 
141 	recv_bytes = args.v1.ucDataOutLen;
142 	if (recv_bytes > recv_size)
143 		recv_bytes = recv_size;
144 
145 	if (recv && recv_size)
146 		radeon_atom_copy_swap(recv, base + 16, recv_bytes, false);
147 
148 	r = recv_bytes;
149 done:
150 	mutex_unlock(&chan->mutex);
151 
152 	return r;
153 }
154 
155 #define BARE_ADDRESS_SIZE 3
156 #define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
157 
158 static ssize_t
159 radeon_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
160 {
161 	struct radeon_i2c_chan *chan =
162 		container_of(aux, struct radeon_i2c_chan, aux);
163 	int ret;
164 	u8 tx_buf[20];
165 	size_t tx_size;
166 	u8 ack, delay = 0;
167 
168 	if (WARN_ON(msg->size > 16))
169 		return -E2BIG;
170 
171 	tx_buf[0] = msg->address & 0xff;
172 	tx_buf[1] = msg->address >> 8;
173 	tx_buf[2] = msg->request << 4;
174 	tx_buf[3] = msg->size ? (msg->size - 1) : 0;
175 
176 	switch (msg->request & ~DP_AUX_I2C_MOT) {
177 	case DP_AUX_NATIVE_WRITE:
178 	case DP_AUX_I2C_WRITE:
179 		/* tx_size needs to be 4 even for bare address packets since the atom
180 		 * table needs the info in tx_buf[3].
181 		 */
182 		tx_size = HEADER_SIZE + msg->size;
183 		if (msg->size == 0)
184 			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
185 		else
186 			tx_buf[3] |= tx_size << 4;
187 		memcpy(tx_buf + HEADER_SIZE, msg->buffer, msg->size);
188 		ret = radeon_process_aux_ch(chan,
189 					    tx_buf, tx_size, NULL, 0, delay, &ack);
190 		if (ret >= 0)
191 			/* Return payload size. */
192 			ret = msg->size;
193 		break;
194 	case DP_AUX_NATIVE_READ:
195 	case DP_AUX_I2C_READ:
196 		/* tx_size needs to be 4 even for bare address packets since the atom
197 		 * table needs the info in tx_buf[3].
198 		 */
199 		tx_size = HEADER_SIZE;
200 		if (msg->size == 0)
201 			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
202 		else
203 			tx_buf[3] |= tx_size << 4;
204 		ret = radeon_process_aux_ch(chan,
205 					    tx_buf, tx_size, msg->buffer, msg->size, delay, &ack);
206 		break;
207 	default:
208 		ret = -EINVAL;
209 		break;
210 	}
211 
212 	if (ret >= 0)
213 		msg->reply = ack >> 4;
214 
215 	return ret;
216 }
217 
218 void radeon_dp_aux_init(struct radeon_connector *radeon_connector)
219 {
220 	int ret;
221 
222 	radeon_connector->ddc_bus->rec.hpd = radeon_connector->hpd.hpd;
223 	radeon_connector->ddc_bus->aux.dev = radeon_connector->base.kdev;
224 	radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer;
225 
226 	ret = drm_dp_aux_register(&radeon_connector->ddc_bus->aux);
227 	if (!ret)
228 		radeon_connector->ddc_bus->has_aux = true;
229 
230 	WARN(ret, "drm_dp_aux_register() failed with error %d\n", ret);
231 }
232 
233 /***** general DP utility functions *****/
234 
235 #define DP_VOLTAGE_MAX         DP_TRAIN_VOLTAGE_SWING_1200
236 #define DP_PRE_EMPHASIS_MAX    DP_TRAIN_PRE_EMPHASIS_9_5
237 
238 static void dp_get_adjust_train(u8 link_status[DP_LINK_STATUS_SIZE],
239 				int lane_count,
240 				u8 train_set[4])
241 {
242 	u8 v = 0;
243 	u8 p = 0;
244 	int lane;
245 
246 	for (lane = 0; lane < lane_count; lane++) {
247 		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
248 		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
249 
250 		DRM_DEBUG_KMS("requested signal parameters: lane %d voltage %s pre_emph %s\n",
251 			  lane,
252 			  voltage_names[this_v >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
253 			  pre_emph_names[this_p >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
254 
255 		if (this_v > v)
256 			v = this_v;
257 		if (this_p > p)
258 			p = this_p;
259 	}
260 
261 	if (v >= DP_VOLTAGE_MAX)
262 		v |= DP_TRAIN_MAX_SWING_REACHED;
263 
264 	if (p >= DP_PRE_EMPHASIS_MAX)
265 		p |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
266 
267 	DRM_DEBUG_KMS("using signal parameters: voltage %s pre_emph %s\n",
268 		  voltage_names[(v & DP_TRAIN_VOLTAGE_SWING_MASK) >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
269 		  pre_emph_names[(p & DP_TRAIN_PRE_EMPHASIS_MASK) >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
270 
271 	for (lane = 0; lane < 4; lane++)
272 		train_set[lane] = v | p;
273 }
274 
275 /* convert bits per color to bits per pixel */
276 /* get bpc from the EDID */
277 static int convert_bpc_to_bpp(int bpc)
278 {
279 	if (bpc == 0)
280 		return 24;
281 	else
282 		return bpc * 3;
283 }
284 
285 /* get the max pix clock supported by the link rate and lane num */
286 static int dp_get_max_dp_pix_clock(int link_rate,
287 				   int lane_num,
288 				   int bpp)
289 {
290 	return (link_rate * lane_num * 8) / bpp;
291 }
292 
293 /***** radeon specific DP functions *****/
294 
295 static int radeon_dp_get_max_link_rate(struct drm_connector *connector,
296 				       u8 dpcd[DP_DPCD_SIZE])
297 {
298 	int max_link_rate;
299 
300 	if (radeon_connector_is_dp12_capable(connector))
301 		max_link_rate = min(drm_dp_max_link_rate(dpcd), 540000);
302 	else
303 		max_link_rate = min(drm_dp_max_link_rate(dpcd), 270000);
304 
305 	return max_link_rate;
306 }
307 
308 /* First get the min lane# when low rate is used according to pixel clock
309  * (prefer low rate), second check max lane# supported by DP panel,
310  * if the max lane# < low rate lane# then use max lane# instead.
311  */
312 static int radeon_dp_get_dp_lane_number(struct drm_connector *connector,
313 					u8 dpcd[DP_DPCD_SIZE],
314 					int pix_clock)
315 {
316 	int bpp = convert_bpc_to_bpp(radeon_get_monitor_bpc(connector));
317 	int max_link_rate = radeon_dp_get_max_link_rate(connector, dpcd);
318 	int max_lane_num = drm_dp_max_lane_count(dpcd);
319 	int lane_num;
320 	int max_dp_pix_clock;
321 
322 	for (lane_num = 1; lane_num < max_lane_num; lane_num <<= 1) {
323 		max_dp_pix_clock = dp_get_max_dp_pix_clock(max_link_rate, lane_num, bpp);
324 		if (pix_clock <= max_dp_pix_clock)
325 			break;
326 	}
327 
328 	return lane_num;
329 }
330 
331 static int radeon_dp_get_dp_link_clock(struct drm_connector *connector,
332 				       u8 dpcd[DP_DPCD_SIZE],
333 				       int pix_clock)
334 {
335 	int bpp = convert_bpc_to_bpp(radeon_get_monitor_bpc(connector));
336 	int lane_num, max_pix_clock;
337 
338 	if (radeon_connector_encoder_get_dp_bridge_encoder_id(connector) ==
339 	    ENCODER_OBJECT_ID_NUTMEG)
340 		return 270000;
341 
342 	lane_num = radeon_dp_get_dp_lane_number(connector, dpcd, pix_clock);
343 	max_pix_clock = dp_get_max_dp_pix_clock(162000, lane_num, bpp);
344 	if (pix_clock <= max_pix_clock)
345 		return 162000;
346 	max_pix_clock = dp_get_max_dp_pix_clock(270000, lane_num, bpp);
347 	if (pix_clock <= max_pix_clock)
348 		return 270000;
349 	if (radeon_connector_is_dp12_capable(connector)) {
350 		max_pix_clock = dp_get_max_dp_pix_clock(540000, lane_num, bpp);
351 		if (pix_clock <= max_pix_clock)
352 			return 540000;
353 	}
354 
355 	return radeon_dp_get_max_link_rate(connector, dpcd);
356 }
357 
358 static u8 radeon_dp_encoder_service(struct radeon_device *rdev,
359 				    int action, int dp_clock,
360 				    u8 ucconfig, u8 lane_num)
361 {
362 	DP_ENCODER_SERVICE_PARAMETERS args;
363 	int index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
364 
365 	memset(&args, 0, sizeof(args));
366 	args.ucLinkClock = dp_clock / 10;
367 	args.ucConfig = ucconfig;
368 	args.ucAction = action;
369 	args.ucLaneNum = lane_num;
370 	args.ucStatus = 0;
371 
372 	atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
373 	return args.ucStatus;
374 }
375 
376 u8 radeon_dp_getsinktype(struct radeon_connector *radeon_connector)
377 {
378 	struct drm_device *dev = radeon_connector->base.dev;
379 	struct radeon_device *rdev = dev->dev_private;
380 
381 	return radeon_dp_encoder_service(rdev, ATOM_DP_ACTION_GET_SINK_TYPE, 0,
382 					 radeon_connector->ddc_bus->rec.i2c_id, 0);
383 }
384 
385 static void radeon_dp_probe_oui(struct radeon_connector *radeon_connector)
386 {
387 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
388 	u8 buf[3];
389 
390 	if (!(dig_connector->dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
391 		return;
392 
393 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_SINK_OUI, buf, 3) == 3)
394 		DRM_DEBUG_KMS("Sink OUI: %02hx%02hx%02hx\n",
395 			      buf[0], buf[1], buf[2]);
396 
397 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_BRANCH_OUI, buf, 3) == 3)
398 		DRM_DEBUG_KMS("Branch OUI: %02hx%02hx%02hx\n",
399 			      buf[0], buf[1], buf[2]);
400 }
401 
402 bool radeon_dp_getdpcd(struct radeon_connector *radeon_connector)
403 {
404 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
405 	u8 msg[DP_DPCD_SIZE];
406 	int ret;
407 
408 	ret = drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_DPCD_REV, msg,
409 			       DP_DPCD_SIZE);
410 	if (ret > 0) {
411 		memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE);
412 
413 		DRM_DEBUG_KMS("DPCD: %*ph\n", (int)sizeof(dig_connector->dpcd),
414 			      dig_connector->dpcd);
415 
416 		radeon_dp_probe_oui(radeon_connector);
417 
418 		return true;
419 	}
420 	dig_connector->dpcd[0] = 0;
421 	return false;
422 }
423 
424 int radeon_dp_get_panel_mode(struct drm_encoder *encoder,
425 			     struct drm_connector *connector)
426 {
427 	struct drm_device *dev = encoder->dev;
428 	struct radeon_device *rdev = dev->dev_private;
429 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
430 	struct radeon_connector_atom_dig *dig_connector;
431 	int panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
432 	u16 dp_bridge = radeon_connector_encoder_get_dp_bridge_encoder_id(connector);
433 	u8 tmp;
434 
435 	if (!ASIC_IS_DCE4(rdev))
436 		return panel_mode;
437 
438 	if (!radeon_connector->con_priv)
439 		return panel_mode;
440 
441 	dig_connector = radeon_connector->con_priv;
442 
443 	if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
444 		/* DP bridge chips */
445 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
446 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
447 			if (tmp & 1)
448 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
449 			else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
450 				 (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
451 				panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
452 			else
453 				panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
454 		}
455 	} else if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
456 		/* eDP */
457 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
458 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
459 			if (tmp & 1)
460 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
461 		}
462 	}
463 
464 	return panel_mode;
465 }
466 
467 void radeon_dp_set_link_config(struct drm_connector *connector,
468 			       const struct drm_display_mode *mode)
469 {
470 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
471 	struct radeon_connector_atom_dig *dig_connector;
472 
473 	if (!radeon_connector->con_priv)
474 		return;
475 	dig_connector = radeon_connector->con_priv;
476 
477 	if ((dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) ||
478 	    (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_eDP)) {
479 		dig_connector->dp_clock =
480 			radeon_dp_get_dp_link_clock(connector, dig_connector->dpcd, mode->clock);
481 		dig_connector->dp_lane_count =
482 			radeon_dp_get_dp_lane_number(connector, dig_connector->dpcd, mode->clock);
483 	}
484 }
485 
486 int radeon_dp_mode_valid_helper(struct drm_connector *connector,
487 				struct drm_display_mode *mode)
488 {
489 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
490 	struct radeon_connector_atom_dig *dig_connector;
491 	int dp_clock;
492 
493 	if (!radeon_connector->con_priv)
494 		return MODE_CLOCK_HIGH;
495 	dig_connector = radeon_connector->con_priv;
496 
497 	dp_clock =
498 		radeon_dp_get_dp_link_clock(connector, dig_connector->dpcd, mode->clock);
499 
500 	if ((dp_clock == 540000) &&
501 	    (!radeon_connector_is_dp12_capable(connector)))
502 		return MODE_CLOCK_HIGH;
503 
504 	return MODE_OK;
505 }
506 
507 bool radeon_dp_needs_link_train(struct radeon_connector *radeon_connector)
508 {
509 	u8 link_status[DP_LINK_STATUS_SIZE];
510 	struct radeon_connector_atom_dig *dig = radeon_connector->con_priv;
511 
512 	if (drm_dp_dpcd_read_link_status(&radeon_connector->ddc_bus->aux, link_status)
513 	    <= 0)
514 		return false;
515 	if (drm_dp_channel_eq_ok(link_status, dig->dp_lane_count))
516 		return false;
517 	return true;
518 }
519 
520 void radeon_dp_set_rx_power_state(struct drm_connector *connector,
521 				  u8 power_state)
522 {
523 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
524 	struct radeon_connector_atom_dig *dig_connector;
525 
526 	if (!radeon_connector->con_priv)
527 		return;
528 
529 	dig_connector = radeon_connector->con_priv;
530 
531 	/* power up/down the sink */
532 	if (dig_connector->dpcd[0] >= 0x11) {
533 		drm_dp_dpcd_writeb(&radeon_connector->ddc_bus->aux,
534 				   DP_SET_POWER, power_state);
535 		usleep_range(1000, 2000);
536 	}
537 }
538 
539 
540 struct radeon_dp_link_train_info {
541 	struct radeon_device *rdev;
542 	struct drm_encoder *encoder;
543 	struct drm_connector *connector;
544 	int enc_id;
545 	int dp_clock;
546 	int dp_lane_count;
547 	bool tp3_supported;
548 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
549 	u8 train_set[4];
550 	u8 link_status[DP_LINK_STATUS_SIZE];
551 	u8 tries;
552 	bool use_dpencoder;
553 	struct drm_dp_aux *aux;
554 };
555 
556 static void radeon_dp_update_vs_emph(struct radeon_dp_link_train_info *dp_info)
557 {
558 	/* set the initial vs/emph on the source */
559 	atombios_dig_transmitter_setup(dp_info->encoder,
560 				       ATOM_TRANSMITTER_ACTION_SETUP_VSEMPH,
561 				       0, dp_info->train_set[0]); /* sets all lanes at once */
562 
563 	/* set the vs/emph on the sink */
564 	drm_dp_dpcd_write(dp_info->aux, DP_TRAINING_LANE0_SET,
565 			  dp_info->train_set, dp_info->dp_lane_count);
566 }
567 
568 static void radeon_dp_set_tp(struct radeon_dp_link_train_info *dp_info, int tp)
569 {
570 	int rtp = 0;
571 
572 	/* set training pattern on the source */
573 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder) {
574 		switch (tp) {
575 		case DP_TRAINING_PATTERN_1:
576 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN1;
577 			break;
578 		case DP_TRAINING_PATTERN_2:
579 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN2;
580 			break;
581 		case DP_TRAINING_PATTERN_3:
582 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN3;
583 			break;
584 		}
585 		atombios_dig_encoder_setup(dp_info->encoder, rtp, 0);
586 	} else {
587 		switch (tp) {
588 		case DP_TRAINING_PATTERN_1:
589 			rtp = 0;
590 			break;
591 		case DP_TRAINING_PATTERN_2:
592 			rtp = 1;
593 			break;
594 		}
595 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_PATTERN_SEL,
596 					  dp_info->dp_clock, dp_info->enc_id, rtp);
597 	}
598 
599 	/* enable training pattern on the sink */
600 	drm_dp_dpcd_writeb(dp_info->aux, DP_TRAINING_PATTERN_SET, tp);
601 }
602 
603 static int radeon_dp_link_train_init(struct radeon_dp_link_train_info *dp_info)
604 {
605 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(dp_info->encoder);
606 	struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
607 	u8 tmp;
608 
609 	/* power up the sink */
610 	radeon_dp_set_rx_power_state(dp_info->connector, DP_SET_POWER_D0);
611 
612 	/* possibly enable downspread on the sink */
613 	if (dp_info->dpcd[3] & 0x1)
614 		drm_dp_dpcd_writeb(dp_info->aux,
615 				   DP_DOWNSPREAD_CTRL, DP_SPREAD_AMP_0_5);
616 	else
617 		drm_dp_dpcd_writeb(dp_info->aux,
618 				   DP_DOWNSPREAD_CTRL, 0);
619 
620 	if ((dp_info->connector->connector_type == DRM_MODE_CONNECTOR_eDP) &&
621 	    (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)) {
622 		drm_dp_dpcd_writeb(dp_info->aux, DP_EDP_CONFIGURATION_SET, 1);
623 	}
624 
625 	/* set the lane count on the sink */
626 	tmp = dp_info->dp_lane_count;
627 	if (drm_dp_enhanced_frame_cap(dp_info->dpcd))
628 		tmp |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
629 	drm_dp_dpcd_writeb(dp_info->aux, DP_LANE_COUNT_SET, tmp);
630 
631 	/* set the link rate on the sink */
632 	tmp = drm_dp_link_rate_to_bw_code(dp_info->dp_clock);
633 	drm_dp_dpcd_writeb(dp_info->aux, DP_LINK_BW_SET, tmp);
634 
635 	/* start training on the source */
636 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
637 		atombios_dig_encoder_setup(dp_info->encoder,
638 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_START, 0);
639 	else
640 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_START,
641 					  dp_info->dp_clock, dp_info->enc_id, 0);
642 
643 	/* disable the training pattern on the sink */
644 	drm_dp_dpcd_writeb(dp_info->aux,
645 			   DP_TRAINING_PATTERN_SET,
646 			   DP_TRAINING_PATTERN_DISABLE);
647 
648 	return 0;
649 }
650 
651 static int radeon_dp_link_train_finish(struct radeon_dp_link_train_info *dp_info)
652 {
653 	udelay(400);
654 
655 	/* disable the training pattern on the sink */
656 	drm_dp_dpcd_writeb(dp_info->aux,
657 			   DP_TRAINING_PATTERN_SET,
658 			   DP_TRAINING_PATTERN_DISABLE);
659 
660 	/* disable the training pattern on the source */
661 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
662 		atombios_dig_encoder_setup(dp_info->encoder,
663 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_COMPLETE, 0);
664 	else
665 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_COMPLETE,
666 					  dp_info->dp_clock, dp_info->enc_id, 0);
667 
668 	return 0;
669 }
670 
671 static int radeon_dp_link_train_cr(struct radeon_dp_link_train_info *dp_info)
672 {
673 	bool clock_recovery;
674  	u8 voltage;
675 	int i;
676 
677 	radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_1);
678 	memset(dp_info->train_set, 0, 4);
679 	radeon_dp_update_vs_emph(dp_info);
680 
681 	udelay(400);
682 
683 	/* clock recovery loop */
684 	clock_recovery = false;
685 	dp_info->tries = 0;
686 	voltage = 0xff;
687 	while (1) {
688 		drm_dp_link_train_clock_recovery_delay(dp_info->dpcd);
689 
690 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
691 						 dp_info->link_status) <= 0) {
692 			DRM_ERROR("displayport link status failed\n");
693 			break;
694 		}
695 
696 		if (drm_dp_clock_recovery_ok(dp_info->link_status, dp_info->dp_lane_count)) {
697 			clock_recovery = true;
698 			break;
699 		}
700 
701 		for (i = 0; i < dp_info->dp_lane_count; i++) {
702 			if ((dp_info->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
703 				break;
704 		}
705 		if (i == dp_info->dp_lane_count) {
706 			DRM_ERROR("clock recovery reached max voltage\n");
707 			break;
708 		}
709 
710 		if ((dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
711 			++dp_info->tries;
712 			if (dp_info->tries == 5) {
713 				DRM_ERROR("clock recovery tried 5 times\n");
714 				break;
715 			}
716 		} else
717 			dp_info->tries = 0;
718 
719 		voltage = dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
720 
721 		/* Compute new train_set as requested by sink */
722 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
723 
724 		radeon_dp_update_vs_emph(dp_info);
725 	}
726 	if (!clock_recovery) {
727 		DRM_ERROR("clock recovery failed\n");
728 		return -1;
729 	} else {
730 		DRM_DEBUG_KMS("clock recovery at voltage %d pre-emphasis %d\n",
731 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
732 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK) >>
733 			  DP_TRAIN_PRE_EMPHASIS_SHIFT);
734 		return 0;
735 	}
736 }
737 
738 static int radeon_dp_link_train_ce(struct radeon_dp_link_train_info *dp_info)
739 {
740 	bool channel_eq;
741 
742 	if (dp_info->tp3_supported)
743 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_3);
744 	else
745 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_2);
746 
747 	/* channel equalization loop */
748 	dp_info->tries = 0;
749 	channel_eq = false;
750 	while (1) {
751 		drm_dp_link_train_channel_eq_delay(dp_info->dpcd);
752 
753 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
754 						 dp_info->link_status) <= 0) {
755 			DRM_ERROR("displayport link status failed\n");
756 			break;
757 		}
758 
759 		if (drm_dp_channel_eq_ok(dp_info->link_status, dp_info->dp_lane_count)) {
760 			channel_eq = true;
761 			break;
762 		}
763 
764 		/* Try 5 times */
765 		if (dp_info->tries > 5) {
766 			DRM_ERROR("channel eq failed: 5 tries\n");
767 			break;
768 		}
769 
770 		/* Compute new train_set as requested by sink */
771 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
772 
773 		radeon_dp_update_vs_emph(dp_info);
774 		dp_info->tries++;
775 	}
776 
777 	if (!channel_eq) {
778 		DRM_ERROR("channel eq failed\n");
779 		return -1;
780 	} else {
781 		DRM_DEBUG_KMS("channel eq at voltage %d pre-emphasis %d\n",
782 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
783 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK)
784 			  >> DP_TRAIN_PRE_EMPHASIS_SHIFT);
785 		return 0;
786 	}
787 }
788 
789 void radeon_dp_link_train(struct drm_encoder *encoder,
790 			  struct drm_connector *connector)
791 {
792 	struct drm_device *dev = encoder->dev;
793 	struct radeon_device *rdev = dev->dev_private;
794 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
795 	struct radeon_encoder_atom_dig *dig;
796 	struct radeon_connector *radeon_connector;
797 	struct radeon_connector_atom_dig *dig_connector;
798 	struct radeon_dp_link_train_info dp_info;
799 	int index;
800 	u8 tmp, frev, crev;
801 
802 	if (!radeon_encoder->enc_priv)
803 		return;
804 	dig = radeon_encoder->enc_priv;
805 
806 	radeon_connector = to_radeon_connector(connector);
807 	if (!radeon_connector->con_priv)
808 		return;
809 	dig_connector = radeon_connector->con_priv;
810 
811 	if ((dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_DISPLAYPORT) &&
812 	    (dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_eDP))
813 		return;
814 
815 	/* DPEncoderService newer than 1.1 can't program properly the
816 	 * training pattern. When facing such version use the
817 	 * DIGXEncoderControl (X== 1 | 2)
818 	 */
819 	dp_info.use_dpencoder = true;
820 	index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
821 	if (atom_parse_cmd_header(rdev->mode_info.atom_context, index, &frev, &crev)) {
822 		if (crev > 1) {
823 			dp_info.use_dpencoder = false;
824 		}
825 	}
826 
827 	dp_info.enc_id = 0;
828 	if (dig->dig_encoder)
829 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG2_ENCODER;
830 	else
831 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG1_ENCODER;
832 	if (dig->linkb)
833 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_B;
834 	else
835 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_A;
836 
837 	if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux, DP_MAX_LANE_COUNT, &tmp)
838 	    == 1) {
839 		if (ASIC_IS_DCE5(rdev) && (tmp & DP_TPS3_SUPPORTED))
840 			dp_info.tp3_supported = true;
841 		else
842 			dp_info.tp3_supported = false;
843 	} else {
844 		dp_info.tp3_supported = false;
845 	}
846 
847 	memcpy(dp_info.dpcd, dig_connector->dpcd, DP_RECEIVER_CAP_SIZE);
848 	dp_info.rdev = rdev;
849 	dp_info.encoder = encoder;
850 	dp_info.connector = connector;
851 	dp_info.dp_lane_count = dig_connector->dp_lane_count;
852 	dp_info.dp_clock = dig_connector->dp_clock;
853 	dp_info.aux = &radeon_connector->ddc_bus->aux;
854 
855 	if (radeon_dp_link_train_init(&dp_info))
856 		goto done;
857 	if (radeon_dp_link_train_cr(&dp_info))
858 		goto done;
859 	if (radeon_dp_link_train_ce(&dp_info))
860 		goto done;
861 done:
862 	if (radeon_dp_link_train_finish(&dp_info))
863 		return;
864 }
865