xref: /linux/drivers/gpu/drm/radeon/atombios_dp.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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/radeon_drm.h>
29 #include "radeon.h"
30 
31 #include "atom.h"
32 #include "atom-bits.h"
33 #include <drm/display/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 so swap as appropriate when copying
49  * data to or from atom. Note that atom operates on dw units.
50  *
51  * Use to_le=true when sending data to atom and provide at least
52  * ALIGN(num_bytes,4) bytes in the dst buffer.
53  *
54  * Use to_le=false when receiving data from atom and provide ALIGN(num_bytes,4)
55  * byes in the src buffer.
56  */
57 void radeon_atom_copy_swap(u8 *dst, u8 *src, u8 num_bytes, bool to_le)
58 {
59 #ifdef __BIG_ENDIAN
60 	u32 src_tmp[5], dst_tmp[5];
61 	int i;
62 	u8 align_num_bytes = ALIGN(num_bytes, 4);
63 
64 	if (to_le) {
65 		memcpy(src_tmp, src, num_bytes);
66 		for (i = 0; i < align_num_bytes / 4; i++)
67 			dst_tmp[i] = cpu_to_le32(src_tmp[i]);
68 		memcpy(dst, dst_tmp, align_num_bytes);
69 	} else {
70 		memcpy(src_tmp, src, align_num_bytes);
71 		for (i = 0; i < align_num_bytes / 4; i++)
72 			dst_tmp[i] = le32_to_cpu(src_tmp[i]);
73 		memcpy(dst, dst_tmp, num_bytes);
74 	}
75 #else
76 	memcpy(dst, src, num_bytes);
77 #endif
78 }
79 
80 union aux_channel_transaction {
81 	PROCESS_AUX_CHANNEL_TRANSACTION_PS_ALLOCATION v1;
82 	PROCESS_AUX_CHANNEL_TRANSACTION_PARAMETERS_V2 v2;
83 };
84 
85 static int radeon_process_aux_ch(struct radeon_i2c_chan *chan,
86 				 u8 *send, int send_bytes,
87 				 u8 *recv, int recv_size,
88 				 u8 delay, u8 *ack)
89 {
90 	struct drm_device *dev = chan->dev;
91 	struct radeon_device *rdev = dev->dev_private;
92 	union aux_channel_transaction args;
93 	int index = GetIndexIntoMasterTable(COMMAND, ProcessAuxChannelTransaction);
94 	unsigned char *base;
95 	int recv_bytes;
96 	int r = 0;
97 
98 	memset(&args, 0, sizeof(args));
99 
100 	mutex_lock(&chan->mutex);
101 	mutex_lock(&rdev->mode_info.atom_context->scratch_mutex);
102 
103 	base = (unsigned char *)(rdev->mode_info.atom_context->scratch + 1);
104 
105 	radeon_atom_copy_swap(base, send, send_bytes, true);
106 
107 	args.v1.lpAuxRequest = cpu_to_le16((u16)(0 + 4));
108 	args.v1.lpDataOut = cpu_to_le16((u16)(16 + 4));
109 	args.v1.ucDataOutLen = 0;
110 	args.v1.ucChannelID = chan->rec.i2c_id;
111 	args.v1.ucDelay = delay / 10;
112 	if (ASIC_IS_DCE4(rdev))
113 		args.v2.ucHPD_ID = chan->rec.hpd;
114 
115 	atom_execute_table_scratch_unlocked(rdev->mode_info.atom_context, index, (uint32_t *)&args, sizeof(args));
116 
117 	*ack = args.v1.ucReplyStatus;
118 
119 	/* timeout */
120 	if (args.v1.ucReplyStatus == 1) {
121 		DRM_DEBUG_KMS("dp_aux_ch timeout\n");
122 		r = -ETIMEDOUT;
123 		goto done;
124 	}
125 
126 	/* flags not zero */
127 	if (args.v1.ucReplyStatus == 2) {
128 		DRM_DEBUG_KMS("dp_aux_ch flags not zero\n");
129 		r = -EIO;
130 		goto done;
131 	}
132 
133 	/* error */
134 	if (args.v1.ucReplyStatus == 3) {
135 		DRM_DEBUG_KMS("dp_aux_ch error\n");
136 		r = -EIO;
137 		goto done;
138 	}
139 
140 	recv_bytes = args.v1.ucDataOutLen;
141 	if (recv_bytes > recv_size)
142 		recv_bytes = recv_size;
143 
144 	if (recv && recv_size)
145 		radeon_atom_copy_swap(recv, base + 16, recv_bytes, false);
146 
147 	r = recv_bytes;
148 done:
149 	mutex_unlock(&rdev->mode_info.atom_context->scratch_mutex);
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_atom(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) & 0xff;
173 	tx_buf[2] = (msg->request << 4) |
174 		((msg->address >> 16) & 0xf);
175 	tx_buf[3] = msg->size ? (msg->size - 1) : 0;
176 
177 	switch (msg->request & ~DP_AUX_I2C_MOT) {
178 	case DP_AUX_NATIVE_WRITE:
179 	case DP_AUX_I2C_WRITE:
180 	case DP_AUX_I2C_WRITE_STATUS_UPDATE:
181 		/* The atom implementation only supports writes with a max payload of
182 		 * 12 bytes since it uses 4 bits for the total count (header + payload)
183 		 * in the parameter space.  The atom interface supports 16 byte
184 		 * payloads for reads. The hw itself supports up to 16 bytes of payload.
185 		 */
186 		if (WARN_ON_ONCE(msg->size > 12))
187 			return -E2BIG;
188 		/* tx_size needs to be 4 even for bare address packets since the atom
189 		 * table needs the info in tx_buf[3].
190 		 */
191 		tx_size = HEADER_SIZE + msg->size;
192 		if (msg->size == 0)
193 			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
194 		else
195 			tx_buf[3] |= tx_size << 4;
196 		memcpy(tx_buf + HEADER_SIZE, msg->buffer, msg->size);
197 		ret = radeon_process_aux_ch(chan,
198 					    tx_buf, tx_size, NULL, 0, delay, &ack);
199 		if (ret >= 0)
200 			/* Return payload size. */
201 			ret = msg->size;
202 		break;
203 	case DP_AUX_NATIVE_READ:
204 	case DP_AUX_I2C_READ:
205 		/* tx_size needs to be 4 even for bare address packets since the atom
206 		 * table needs the info in tx_buf[3].
207 		 */
208 		tx_size = HEADER_SIZE;
209 		if (msg->size == 0)
210 			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
211 		else
212 			tx_buf[3] |= tx_size << 4;
213 		ret = radeon_process_aux_ch(chan,
214 					    tx_buf, tx_size, msg->buffer, msg->size, delay, &ack);
215 		break;
216 	default:
217 		ret = -EINVAL;
218 		break;
219 	}
220 
221 	if (ret >= 0)
222 		msg->reply = ack >> 4;
223 
224 	return ret;
225 }
226 
227 void radeon_dp_aux_init(struct radeon_connector *radeon_connector)
228 {
229 	struct drm_device *dev = radeon_connector->base.dev;
230 	struct radeon_device *rdev = dev->dev_private;
231 
232 	radeon_connector->ddc_bus->rec.hpd = radeon_connector->hpd.hpd;
233 	radeon_connector->ddc_bus->aux.drm_dev = radeon_connector->base.dev;
234 	if (ASIC_IS_DCE5(rdev)) {
235 		if (radeon_auxch)
236 			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_native;
237 		else
238 			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
239 	} else {
240 		radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
241 	}
242 
243 	drm_dp_aux_init(&radeon_connector->ddc_bus->aux);
244 	radeon_connector->ddc_bus->has_aux = true;
245 }
246 
247 /***** general DP utility functions *****/
248 
249 #define DP_VOLTAGE_MAX         DP_TRAIN_VOLTAGE_SWING_LEVEL_3
250 #define DP_PRE_EMPHASIS_MAX    DP_TRAIN_PRE_EMPH_LEVEL_3
251 
252 static void dp_get_adjust_train(const u8 link_status[DP_LINK_STATUS_SIZE],
253 				int lane_count,
254 				u8 train_set[4])
255 {
256 	u8 v = 0;
257 	u8 p = 0;
258 	int lane;
259 
260 	for (lane = 0; lane < lane_count; lane++) {
261 		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
262 		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
263 
264 		DRM_DEBUG_KMS("requested signal parameters: lane %d voltage %s pre_emph %s\n",
265 			  lane,
266 			  voltage_names[this_v >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
267 			  pre_emph_names[this_p >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
268 
269 		if (this_v > v)
270 			v = this_v;
271 		if (this_p > p)
272 			p = this_p;
273 	}
274 
275 	if (v >= DP_VOLTAGE_MAX)
276 		v |= DP_TRAIN_MAX_SWING_REACHED;
277 
278 	if (p >= DP_PRE_EMPHASIS_MAX)
279 		p |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
280 
281 	DRM_DEBUG_KMS("using signal parameters: voltage %s pre_emph %s\n",
282 		  voltage_names[(v & DP_TRAIN_VOLTAGE_SWING_MASK) >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
283 		  pre_emph_names[(p & DP_TRAIN_PRE_EMPHASIS_MASK) >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
284 
285 	for (lane = 0; lane < 4; lane++)
286 		train_set[lane] = v | p;
287 }
288 
289 /* convert bits per color to bits per pixel */
290 /* get bpc from the EDID */
291 static int convert_bpc_to_bpp(int bpc)
292 {
293 	if (bpc == 0)
294 		return 24;
295 	else
296 		return bpc * 3;
297 }
298 
299 /***** radeon specific DP functions *****/
300 
301 static int radeon_dp_get_dp_link_config(struct drm_connector *connector,
302 					const u8 dpcd[DP_DPCD_SIZE],
303 					unsigned pix_clock,
304 					unsigned *dp_lanes, unsigned *dp_rate)
305 {
306 	int bpp = convert_bpc_to_bpp(radeon_get_monitor_bpc(connector));
307 	static const unsigned link_rates[3] = { 162000, 270000, 540000 };
308 	unsigned max_link_rate = drm_dp_max_link_rate(dpcd);
309 	unsigned max_lane_num = drm_dp_max_lane_count(dpcd);
310 	unsigned lane_num, i, max_pix_clock;
311 
312 	if (radeon_connector_encoder_get_dp_bridge_encoder_id(connector) ==
313 	    ENCODER_OBJECT_ID_NUTMEG) {
314 		for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
315 			max_pix_clock = (lane_num * 270000 * 8) / bpp;
316 			if (max_pix_clock >= pix_clock) {
317 				*dp_lanes = lane_num;
318 				*dp_rate = 270000;
319 				return 0;
320 			}
321 		}
322 	} else {
323 		for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) {
324 			for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
325 				max_pix_clock = (lane_num * link_rates[i] * 8) / bpp;
326 				if (max_pix_clock >= pix_clock) {
327 					*dp_lanes = lane_num;
328 					*dp_rate = link_rates[i];
329 					return 0;
330 				}
331 			}
332 		}
333 	}
334 
335 	return -EINVAL;
336 }
337 
338 static u8 radeon_dp_encoder_service(struct radeon_device *rdev,
339 				    int action, int dp_clock,
340 				    u8 ucconfig, u8 lane_num)
341 {
342 	DP_ENCODER_SERVICE_PARAMETERS args;
343 	int index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
344 
345 	memset(&args, 0, sizeof(args));
346 	args.ucLinkClock = dp_clock / 10;
347 	args.ucConfig = ucconfig;
348 	args.ucAction = action;
349 	args.ucLaneNum = lane_num;
350 	args.ucStatus = 0;
351 
352 	atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args, sizeof(args));
353 	return args.ucStatus;
354 }
355 
356 u8 radeon_dp_getsinktype(struct radeon_connector *radeon_connector)
357 {
358 	struct drm_device *dev = radeon_connector->base.dev;
359 	struct radeon_device *rdev = dev->dev_private;
360 
361 	return radeon_dp_encoder_service(rdev, ATOM_DP_ACTION_GET_SINK_TYPE, 0,
362 					 radeon_connector->ddc_bus->rec.i2c_id, 0);
363 }
364 
365 static void radeon_dp_probe_oui(struct radeon_connector *radeon_connector)
366 {
367 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
368 	u8 buf[3];
369 
370 	if (!(dig_connector->dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
371 		return;
372 
373 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_SINK_OUI, buf, 3) == 3)
374 		DRM_DEBUG_KMS("Sink OUI: %02hx%02hx%02hx\n",
375 			      buf[0], buf[1], buf[2]);
376 
377 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_BRANCH_OUI, buf, 3) == 3)
378 		DRM_DEBUG_KMS("Branch OUI: %02hx%02hx%02hx\n",
379 			      buf[0], buf[1], buf[2]);
380 }
381 
382 bool radeon_dp_getdpcd(struct radeon_connector *radeon_connector)
383 {
384 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
385 	u8 msg[DP_DPCD_SIZE];
386 	int ret;
387 
388 	ret = drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_DPCD_REV, msg,
389 			       DP_DPCD_SIZE);
390 	if (ret == DP_DPCD_SIZE) {
391 		memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE);
392 
393 		DRM_DEBUG_KMS("DPCD: %*ph\n", (int)sizeof(dig_connector->dpcd),
394 			      dig_connector->dpcd);
395 
396 		radeon_dp_probe_oui(radeon_connector);
397 
398 		return true;
399 	}
400 
401 	dig_connector->dpcd[0] = 0;
402 	return false;
403 }
404 
405 int radeon_dp_get_panel_mode(struct drm_encoder *encoder,
406 			     struct drm_connector *connector)
407 {
408 	struct drm_device *dev = encoder->dev;
409 	struct radeon_device *rdev = dev->dev_private;
410 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
411 	int panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
412 	u16 dp_bridge = radeon_connector_encoder_get_dp_bridge_encoder_id(connector);
413 	u8 tmp;
414 
415 	if (!ASIC_IS_DCE4(rdev))
416 		return panel_mode;
417 
418 	if (!radeon_connector->con_priv)
419 		return panel_mode;
420 
421 	if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
422 		/* DP bridge chips */
423 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
424 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
425 			if (tmp & 1)
426 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
427 			else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
428 				 (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
429 				panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
430 			else
431 				panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
432 		}
433 	} else if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
434 		/* eDP */
435 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
436 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
437 			if (tmp & 1)
438 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
439 		}
440 	}
441 
442 	return panel_mode;
443 }
444 
445 void radeon_dp_set_link_config(struct drm_connector *connector,
446 			       const struct drm_display_mode *mode)
447 {
448 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
449 	struct radeon_connector_atom_dig *dig_connector;
450 	int ret;
451 
452 	if (!radeon_connector->con_priv)
453 		return;
454 	dig_connector = radeon_connector->con_priv;
455 
456 	if ((dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) ||
457 	    (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_eDP)) {
458 		ret = radeon_dp_get_dp_link_config(connector, dig_connector->dpcd,
459 						   mode->clock,
460 						   &dig_connector->dp_lane_count,
461 						   &dig_connector->dp_clock);
462 		if (ret) {
463 			dig_connector->dp_clock = 0;
464 			dig_connector->dp_lane_count = 0;
465 		}
466 	}
467 }
468 
469 int radeon_dp_mode_valid_helper(struct drm_connector *connector,
470 				struct drm_display_mode *mode)
471 {
472 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
473 	struct radeon_connector_atom_dig *dig_connector;
474 	unsigned dp_clock, dp_lanes;
475 	int ret;
476 
477 	if ((mode->clock > 340000) &&
478 	    (!radeon_connector_is_dp12_capable(connector)))
479 		return MODE_CLOCK_HIGH;
480 
481 	if (!radeon_connector->con_priv)
482 		return MODE_CLOCK_HIGH;
483 	dig_connector = radeon_connector->con_priv;
484 
485 	ret = radeon_dp_get_dp_link_config(connector, dig_connector->dpcd,
486 					   mode->clock,
487 					   &dp_lanes,
488 					   &dp_clock);
489 	if (ret)
490 		return MODE_CLOCK_HIGH;
491 
492 	if ((dp_clock == 540000) &&
493 	    (!radeon_connector_is_dp12_capable(connector)))
494 		return MODE_CLOCK_HIGH;
495 
496 	return MODE_OK;
497 }
498 
499 bool radeon_dp_needs_link_train(struct radeon_connector *radeon_connector)
500 {
501 	u8 link_status[DP_LINK_STATUS_SIZE];
502 	struct radeon_connector_atom_dig *dig = radeon_connector->con_priv;
503 
504 	if (drm_dp_dpcd_read_link_status(&radeon_connector->ddc_bus->aux, link_status)
505 	    <= 0)
506 		return false;
507 	if (drm_dp_channel_eq_ok(link_status, dig->dp_lane_count))
508 		return false;
509 	return true;
510 }
511 
512 void radeon_dp_set_rx_power_state(struct drm_connector *connector,
513 				  u8 power_state)
514 {
515 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
516 	struct radeon_connector_atom_dig *dig_connector;
517 
518 	if (!radeon_connector->con_priv)
519 		return;
520 
521 	dig_connector = radeon_connector->con_priv;
522 
523 	/* power up/down the sink */
524 	if (dig_connector->dpcd[0] >= 0x11) {
525 		drm_dp_dpcd_writeb(&radeon_connector->ddc_bus->aux,
526 				   DP_SET_POWER, power_state);
527 		usleep_range(1000, 2000);
528 	}
529 }
530 
531 
532 struct radeon_dp_link_train_info {
533 	struct radeon_device *rdev;
534 	struct drm_encoder *encoder;
535 	struct drm_connector *connector;
536 	int enc_id;
537 	int dp_clock;
538 	int dp_lane_count;
539 	bool tp3_supported;
540 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
541 	u8 train_set[4];
542 	u8 link_status[DP_LINK_STATUS_SIZE];
543 	u8 tries;
544 	bool use_dpencoder;
545 	struct drm_dp_aux *aux;
546 };
547 
548 static void radeon_dp_update_vs_emph(struct radeon_dp_link_train_info *dp_info)
549 {
550 	/* set the initial vs/emph on the source */
551 	atombios_dig_transmitter_setup(dp_info->encoder,
552 				       ATOM_TRANSMITTER_ACTION_SETUP_VSEMPH,
553 				       0, dp_info->train_set[0]); /* sets all lanes at once */
554 
555 	/* set the vs/emph on the sink */
556 	drm_dp_dpcd_write(dp_info->aux, DP_TRAINING_LANE0_SET,
557 			  dp_info->train_set, dp_info->dp_lane_count);
558 }
559 
560 static void radeon_dp_set_tp(struct radeon_dp_link_train_info *dp_info, int tp)
561 {
562 	int rtp = 0;
563 
564 	/* set training pattern on the source */
565 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder) {
566 		switch (tp) {
567 		case DP_TRAINING_PATTERN_1:
568 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN1;
569 			break;
570 		case DP_TRAINING_PATTERN_2:
571 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN2;
572 			break;
573 		case DP_TRAINING_PATTERN_3:
574 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN3;
575 			break;
576 		}
577 		atombios_dig_encoder_setup(dp_info->encoder, rtp, 0);
578 	} else {
579 		switch (tp) {
580 		case DP_TRAINING_PATTERN_1:
581 			rtp = 0;
582 			break;
583 		case DP_TRAINING_PATTERN_2:
584 			rtp = 1;
585 			break;
586 		}
587 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_PATTERN_SEL,
588 					  dp_info->dp_clock, dp_info->enc_id, rtp);
589 	}
590 
591 	/* enable training pattern on the sink */
592 	drm_dp_dpcd_writeb(dp_info->aux, DP_TRAINING_PATTERN_SET, tp);
593 }
594 
595 static int radeon_dp_link_train_init(struct radeon_dp_link_train_info *dp_info)
596 {
597 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(dp_info->encoder);
598 	struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
599 	u8 tmp;
600 
601 	/* power up the sink */
602 	radeon_dp_set_rx_power_state(dp_info->connector, DP_SET_POWER_D0);
603 
604 	/* possibly enable downspread on the sink */
605 	if (dp_info->dpcd[3] & 0x1)
606 		drm_dp_dpcd_writeb(dp_info->aux,
607 				   DP_DOWNSPREAD_CTRL, DP_SPREAD_AMP_0_5);
608 	else
609 		drm_dp_dpcd_writeb(dp_info->aux,
610 				   DP_DOWNSPREAD_CTRL, 0);
611 
612 	if (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)
613 		drm_dp_dpcd_writeb(dp_info->aux, DP_EDP_CONFIGURATION_SET, 1);
614 
615 	/* set the lane count on the sink */
616 	tmp = dp_info->dp_lane_count;
617 	if (drm_dp_enhanced_frame_cap(dp_info->dpcd))
618 		tmp |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
619 	drm_dp_dpcd_writeb(dp_info->aux, DP_LANE_COUNT_SET, tmp);
620 
621 	/* set the link rate on the sink */
622 	tmp = drm_dp_link_rate_to_bw_code(dp_info->dp_clock);
623 	drm_dp_dpcd_writeb(dp_info->aux, DP_LINK_BW_SET, tmp);
624 
625 	/* start training on the source */
626 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
627 		atombios_dig_encoder_setup(dp_info->encoder,
628 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_START, 0);
629 	else
630 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_START,
631 					  dp_info->dp_clock, dp_info->enc_id, 0);
632 
633 	/* disable the training pattern on the sink */
634 	drm_dp_dpcd_writeb(dp_info->aux,
635 			   DP_TRAINING_PATTERN_SET,
636 			   DP_TRAINING_PATTERN_DISABLE);
637 
638 	return 0;
639 }
640 
641 static int radeon_dp_link_train_finish(struct radeon_dp_link_train_info *dp_info)
642 {
643 	udelay(400);
644 
645 	/* disable the training pattern on the sink */
646 	drm_dp_dpcd_writeb(dp_info->aux,
647 			   DP_TRAINING_PATTERN_SET,
648 			   DP_TRAINING_PATTERN_DISABLE);
649 
650 	/* disable the training pattern on the source */
651 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
652 		atombios_dig_encoder_setup(dp_info->encoder,
653 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_COMPLETE, 0);
654 	else
655 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_COMPLETE,
656 					  dp_info->dp_clock, dp_info->enc_id, 0);
657 
658 	return 0;
659 }
660 
661 static int radeon_dp_link_train_cr(struct radeon_dp_link_train_info *dp_info)
662 {
663 	bool clock_recovery;
664  	u8 voltage;
665 	int i;
666 
667 	radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_1);
668 	memset(dp_info->train_set, 0, 4);
669 	radeon_dp_update_vs_emph(dp_info);
670 
671 	udelay(400);
672 
673 	/* clock recovery loop */
674 	clock_recovery = false;
675 	dp_info->tries = 0;
676 	voltage = 0xff;
677 	while (1) {
678 		drm_dp_link_train_clock_recovery_delay(dp_info->aux, dp_info->dpcd);
679 
680 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
681 						 dp_info->link_status) <= 0) {
682 			DRM_ERROR("displayport link status failed\n");
683 			break;
684 		}
685 
686 		if (drm_dp_clock_recovery_ok(dp_info->link_status, dp_info->dp_lane_count)) {
687 			clock_recovery = true;
688 			break;
689 		}
690 
691 		for (i = 0; i < dp_info->dp_lane_count; i++) {
692 			if ((dp_info->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
693 				break;
694 		}
695 		if (i == dp_info->dp_lane_count) {
696 			DRM_ERROR("clock recovery reached max voltage\n");
697 			break;
698 		}
699 
700 		if ((dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
701 			++dp_info->tries;
702 			if (dp_info->tries == 5) {
703 				DRM_ERROR("clock recovery tried 5 times\n");
704 				break;
705 			}
706 		} else
707 			dp_info->tries = 0;
708 
709 		voltage = dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
710 
711 		/* Compute new train_set as requested by sink */
712 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
713 
714 		radeon_dp_update_vs_emph(dp_info);
715 	}
716 	if (!clock_recovery) {
717 		DRM_ERROR("clock recovery failed\n");
718 		return -1;
719 	} else {
720 		DRM_DEBUG_KMS("clock recovery at voltage %d pre-emphasis %d\n",
721 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
722 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK) >>
723 			  DP_TRAIN_PRE_EMPHASIS_SHIFT);
724 		return 0;
725 	}
726 }
727 
728 static int radeon_dp_link_train_ce(struct radeon_dp_link_train_info *dp_info)
729 {
730 	bool channel_eq;
731 
732 	if (dp_info->tp3_supported)
733 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_3);
734 	else
735 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_2);
736 
737 	/* channel equalization loop */
738 	dp_info->tries = 0;
739 	channel_eq = false;
740 	while (1) {
741 		drm_dp_link_train_channel_eq_delay(dp_info->aux, dp_info->dpcd);
742 
743 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
744 						 dp_info->link_status) <= 0) {
745 			DRM_ERROR("displayport link status failed\n");
746 			break;
747 		}
748 
749 		if (drm_dp_channel_eq_ok(dp_info->link_status, dp_info->dp_lane_count)) {
750 			channel_eq = true;
751 			break;
752 		}
753 
754 		/* Try 5 times */
755 		if (dp_info->tries > 5) {
756 			DRM_ERROR("channel eq failed: 5 tries\n");
757 			break;
758 		}
759 
760 		/* Compute new train_set as requested by sink */
761 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
762 
763 		radeon_dp_update_vs_emph(dp_info);
764 		dp_info->tries++;
765 	}
766 
767 	if (!channel_eq) {
768 		DRM_ERROR("channel eq failed\n");
769 		return -1;
770 	} else {
771 		DRM_DEBUG_KMS("channel eq at voltage %d pre-emphasis %d\n",
772 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
773 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK)
774 			  >> DP_TRAIN_PRE_EMPHASIS_SHIFT);
775 		return 0;
776 	}
777 }
778 
779 void radeon_dp_link_train(struct drm_encoder *encoder,
780 			  struct drm_connector *connector)
781 {
782 	struct drm_device *dev = encoder->dev;
783 	struct radeon_device *rdev = dev->dev_private;
784 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
785 	struct radeon_encoder_atom_dig *dig;
786 	struct radeon_connector *radeon_connector;
787 	struct radeon_connector_atom_dig *dig_connector;
788 	struct radeon_dp_link_train_info dp_info;
789 	int index;
790 	u8 tmp, frev, crev;
791 
792 	if (!radeon_encoder->enc_priv)
793 		return;
794 	dig = radeon_encoder->enc_priv;
795 
796 	radeon_connector = to_radeon_connector(connector);
797 	if (!radeon_connector->con_priv)
798 		return;
799 	dig_connector = radeon_connector->con_priv;
800 
801 	if ((dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_DISPLAYPORT) &&
802 	    (dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_eDP))
803 		return;
804 
805 	/* DPEncoderService newer than 1.1 can't program properly the
806 	 * training pattern. When facing such version use the
807 	 * DIGXEncoderControl (X== 1 | 2)
808 	 */
809 	dp_info.use_dpencoder = true;
810 	index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
811 	if (atom_parse_cmd_header(rdev->mode_info.atom_context, index, &frev, &crev)) {
812 		if (crev > 1)
813 			dp_info.use_dpencoder = false;
814 	}
815 
816 	dp_info.enc_id = 0;
817 	if (dig->dig_encoder)
818 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG2_ENCODER;
819 	else
820 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG1_ENCODER;
821 	if (dig->linkb)
822 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_B;
823 	else
824 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_A;
825 
826 	if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux, DP_MAX_LANE_COUNT, &tmp)
827 	    == 1) {
828 		if (ASIC_IS_DCE5(rdev) && (tmp & DP_TPS3_SUPPORTED))
829 			dp_info.tp3_supported = true;
830 		else
831 			dp_info.tp3_supported = false;
832 	} else {
833 		dp_info.tp3_supported = false;
834 	}
835 
836 	memcpy(dp_info.dpcd, dig_connector->dpcd, DP_RECEIVER_CAP_SIZE);
837 	dp_info.rdev = rdev;
838 	dp_info.encoder = encoder;
839 	dp_info.connector = connector;
840 	dp_info.dp_lane_count = dig_connector->dp_lane_count;
841 	dp_info.dp_clock = dig_connector->dp_clock;
842 	dp_info.aux = &radeon_connector->ddc_bus->aux;
843 
844 	if (radeon_dp_link_train_init(&dp_info))
845 		goto done;
846 	if (radeon_dp_link_train_cr(&dp_info))
847 		goto done;
848 	if (radeon_dp_link_train_ce(&dp_info))
849 		goto done;
850 done:
851 	if (radeon_dp_link_train_finish(&dp_info))
852 		return;
853 }
854