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/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);
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 	int ret;
232 
233 	radeon_connector->ddc_bus->rec.hpd = radeon_connector->hpd.hpd;
234 	radeon_connector->ddc_bus->aux.dev = radeon_connector->base.kdev;
235 	if (ASIC_IS_DCE5(rdev)) {
236 		if (radeon_auxch)
237 			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_native;
238 		else
239 			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
240 	} else {
241 		radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
242 	}
243 
244 	ret = drm_dp_aux_register(&radeon_connector->ddc_bus->aux);
245 	if (!ret)
246 		radeon_connector->ddc_bus->has_aux = true;
247 
248 	WARN(ret, "drm_dp_aux_register() failed with error %d\n", ret);
249 }
250 
251 /***** general DP utility functions *****/
252 
253 #define DP_VOLTAGE_MAX         DP_TRAIN_VOLTAGE_SWING_LEVEL_3
254 #define DP_PRE_EMPHASIS_MAX    DP_TRAIN_PRE_EMPH_LEVEL_3
255 
256 static void dp_get_adjust_train(const u8 link_status[DP_LINK_STATUS_SIZE],
257 				int lane_count,
258 				u8 train_set[4])
259 {
260 	u8 v = 0;
261 	u8 p = 0;
262 	int lane;
263 
264 	for (lane = 0; lane < lane_count; lane++) {
265 		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
266 		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
267 
268 		DRM_DEBUG_KMS("requested signal parameters: lane %d voltage %s pre_emph %s\n",
269 			  lane,
270 			  voltage_names[this_v >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
271 			  pre_emph_names[this_p >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
272 
273 		if (this_v > v)
274 			v = this_v;
275 		if (this_p > p)
276 			p = this_p;
277 	}
278 
279 	if (v >= DP_VOLTAGE_MAX)
280 		v |= DP_TRAIN_MAX_SWING_REACHED;
281 
282 	if (p >= DP_PRE_EMPHASIS_MAX)
283 		p |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
284 
285 	DRM_DEBUG_KMS("using signal parameters: voltage %s pre_emph %s\n",
286 		  voltage_names[(v & DP_TRAIN_VOLTAGE_SWING_MASK) >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
287 		  pre_emph_names[(p & DP_TRAIN_PRE_EMPHASIS_MASK) >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
288 
289 	for (lane = 0; lane < 4; lane++)
290 		train_set[lane] = v | p;
291 }
292 
293 /* convert bits per color to bits per pixel */
294 /* get bpc from the EDID */
295 static int convert_bpc_to_bpp(int bpc)
296 {
297 	if (bpc == 0)
298 		return 24;
299 	else
300 		return bpc * 3;
301 }
302 
303 /***** radeon specific DP functions *****/
304 
305 static int radeon_dp_get_dp_link_config(struct drm_connector *connector,
306 					const u8 dpcd[DP_DPCD_SIZE],
307 					unsigned pix_clock,
308 					unsigned *dp_lanes, unsigned *dp_rate)
309 {
310 	int bpp = convert_bpc_to_bpp(radeon_get_monitor_bpc(connector));
311 	static const unsigned link_rates[3] = { 162000, 270000, 540000 };
312 	unsigned max_link_rate = drm_dp_max_link_rate(dpcd);
313 	unsigned max_lane_num = drm_dp_max_lane_count(dpcd);
314 	unsigned lane_num, i, max_pix_clock;
315 
316 	if (radeon_connector_encoder_get_dp_bridge_encoder_id(connector) ==
317 	    ENCODER_OBJECT_ID_NUTMEG) {
318 		for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
319 			max_pix_clock = (lane_num * 270000 * 8) / bpp;
320 			if (max_pix_clock >= pix_clock) {
321 				*dp_lanes = lane_num;
322 				*dp_rate = 270000;
323 				return 0;
324 			}
325 		}
326 	} else {
327 		for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) {
328 			for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
329 				max_pix_clock = (lane_num * link_rates[i] * 8) / bpp;
330 				if (max_pix_clock >= pix_clock) {
331 					*dp_lanes = lane_num;
332 					*dp_rate = link_rates[i];
333 					return 0;
334 				}
335 			}
336 		}
337 	}
338 
339 	return -EINVAL;
340 }
341 
342 static u8 radeon_dp_encoder_service(struct radeon_device *rdev,
343 				    int action, int dp_clock,
344 				    u8 ucconfig, u8 lane_num)
345 {
346 	DP_ENCODER_SERVICE_PARAMETERS args;
347 	int index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
348 
349 	memset(&args, 0, sizeof(args));
350 	args.ucLinkClock = dp_clock / 10;
351 	args.ucConfig = ucconfig;
352 	args.ucAction = action;
353 	args.ucLaneNum = lane_num;
354 	args.ucStatus = 0;
355 
356 	atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
357 	return args.ucStatus;
358 }
359 
360 u8 radeon_dp_getsinktype(struct radeon_connector *radeon_connector)
361 {
362 	struct drm_device *dev = radeon_connector->base.dev;
363 	struct radeon_device *rdev = dev->dev_private;
364 
365 	return radeon_dp_encoder_service(rdev, ATOM_DP_ACTION_GET_SINK_TYPE, 0,
366 					 radeon_connector->ddc_bus->rec.i2c_id, 0);
367 }
368 
369 static void radeon_dp_probe_oui(struct radeon_connector *radeon_connector)
370 {
371 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
372 	u8 buf[3];
373 
374 	if (!(dig_connector->dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
375 		return;
376 
377 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_SINK_OUI, buf, 3) == 3)
378 		DRM_DEBUG_KMS("Sink OUI: %02hx%02hx%02hx\n",
379 			      buf[0], buf[1], buf[2]);
380 
381 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_BRANCH_OUI, buf, 3) == 3)
382 		DRM_DEBUG_KMS("Branch OUI: %02hx%02hx%02hx\n",
383 			      buf[0], buf[1], buf[2]);
384 }
385 
386 bool radeon_dp_getdpcd(struct radeon_connector *radeon_connector)
387 {
388 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
389 	u8 msg[DP_DPCD_SIZE];
390 	int ret;
391 
392 	ret = drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_DPCD_REV, msg,
393 			       DP_DPCD_SIZE);
394 	if (ret == DP_DPCD_SIZE) {
395 		memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE);
396 
397 		DRM_DEBUG_KMS("DPCD: %*ph\n", (int)sizeof(dig_connector->dpcd),
398 			      dig_connector->dpcd);
399 
400 		radeon_dp_probe_oui(radeon_connector);
401 
402 		return true;
403 	}
404 
405 	dig_connector->dpcd[0] = 0;
406 	return false;
407 }
408 
409 int radeon_dp_get_panel_mode(struct drm_encoder *encoder,
410 			     struct drm_connector *connector)
411 {
412 	struct drm_device *dev = encoder->dev;
413 	struct radeon_device *rdev = dev->dev_private;
414 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
415 	int panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
416 	u16 dp_bridge = radeon_connector_encoder_get_dp_bridge_encoder_id(connector);
417 	u8 tmp;
418 
419 	if (!ASIC_IS_DCE4(rdev))
420 		return panel_mode;
421 
422 	if (!radeon_connector->con_priv)
423 		return panel_mode;
424 
425 	if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
426 		/* DP bridge chips */
427 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
428 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
429 			if (tmp & 1)
430 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
431 			else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
432 				 (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
433 				panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
434 			else
435 				panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
436 		}
437 	} else if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
438 		/* eDP */
439 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
440 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
441 			if (tmp & 1)
442 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
443 		}
444 	}
445 
446 	return panel_mode;
447 }
448 
449 void radeon_dp_set_link_config(struct drm_connector *connector,
450 			       const struct drm_display_mode *mode)
451 {
452 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
453 	struct radeon_connector_atom_dig *dig_connector;
454 	int ret;
455 
456 	if (!radeon_connector->con_priv)
457 		return;
458 	dig_connector = radeon_connector->con_priv;
459 
460 	if ((dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) ||
461 	    (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_eDP)) {
462 		ret = radeon_dp_get_dp_link_config(connector, dig_connector->dpcd,
463 						   mode->clock,
464 						   &dig_connector->dp_lane_count,
465 						   &dig_connector->dp_clock);
466 		if (ret) {
467 			dig_connector->dp_clock = 0;
468 			dig_connector->dp_lane_count = 0;
469 		}
470 	}
471 }
472 
473 int radeon_dp_mode_valid_helper(struct drm_connector *connector,
474 				struct drm_display_mode *mode)
475 {
476 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
477 	struct radeon_connector_atom_dig *dig_connector;
478 	unsigned dp_clock, dp_lanes;
479 	int ret;
480 
481 	if ((mode->clock > 340000) &&
482 	    (!radeon_connector_is_dp12_capable(connector)))
483 		return MODE_CLOCK_HIGH;
484 
485 	if (!radeon_connector->con_priv)
486 		return MODE_CLOCK_HIGH;
487 	dig_connector = radeon_connector->con_priv;
488 
489 	ret = radeon_dp_get_dp_link_config(connector, dig_connector->dpcd,
490 					   mode->clock,
491 					   &dp_lanes,
492 					   &dp_clock);
493 	if (ret)
494 		return MODE_CLOCK_HIGH;
495 
496 	if ((dp_clock == 540000) &&
497 	    (!radeon_connector_is_dp12_capable(connector)))
498 		return MODE_CLOCK_HIGH;
499 
500 	return MODE_OK;
501 }
502 
503 bool radeon_dp_needs_link_train(struct radeon_connector *radeon_connector)
504 {
505 	u8 link_status[DP_LINK_STATUS_SIZE];
506 	struct radeon_connector_atom_dig *dig = radeon_connector->con_priv;
507 
508 	if (drm_dp_dpcd_read_link_status(&radeon_connector->ddc_bus->aux, link_status)
509 	    <= 0)
510 		return false;
511 	if (drm_dp_channel_eq_ok(link_status, dig->dp_lane_count))
512 		return false;
513 	return true;
514 }
515 
516 void radeon_dp_set_rx_power_state(struct drm_connector *connector,
517 				  u8 power_state)
518 {
519 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
520 	struct radeon_connector_atom_dig *dig_connector;
521 
522 	if (!radeon_connector->con_priv)
523 		return;
524 
525 	dig_connector = radeon_connector->con_priv;
526 
527 	/* power up/down the sink */
528 	if (dig_connector->dpcd[0] >= 0x11) {
529 		drm_dp_dpcd_writeb(&radeon_connector->ddc_bus->aux,
530 				   DP_SET_POWER, power_state);
531 		usleep_range(1000, 2000);
532 	}
533 }
534 
535 
536 struct radeon_dp_link_train_info {
537 	struct radeon_device *rdev;
538 	struct drm_encoder *encoder;
539 	struct drm_connector *connector;
540 	int enc_id;
541 	int dp_clock;
542 	int dp_lane_count;
543 	bool tp3_supported;
544 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
545 	u8 train_set[4];
546 	u8 link_status[DP_LINK_STATUS_SIZE];
547 	u8 tries;
548 	bool use_dpencoder;
549 	struct drm_dp_aux *aux;
550 };
551 
552 static void radeon_dp_update_vs_emph(struct radeon_dp_link_train_info *dp_info)
553 {
554 	/* set the initial vs/emph on the source */
555 	atombios_dig_transmitter_setup(dp_info->encoder,
556 				       ATOM_TRANSMITTER_ACTION_SETUP_VSEMPH,
557 				       0, dp_info->train_set[0]); /* sets all lanes at once */
558 
559 	/* set the vs/emph on the sink */
560 	drm_dp_dpcd_write(dp_info->aux, DP_TRAINING_LANE0_SET,
561 			  dp_info->train_set, dp_info->dp_lane_count);
562 }
563 
564 static void radeon_dp_set_tp(struct radeon_dp_link_train_info *dp_info, int tp)
565 {
566 	int rtp = 0;
567 
568 	/* set training pattern on the source */
569 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder) {
570 		switch (tp) {
571 		case DP_TRAINING_PATTERN_1:
572 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN1;
573 			break;
574 		case DP_TRAINING_PATTERN_2:
575 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN2;
576 			break;
577 		case DP_TRAINING_PATTERN_3:
578 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN3;
579 			break;
580 		}
581 		atombios_dig_encoder_setup(dp_info->encoder, rtp, 0);
582 	} else {
583 		switch (tp) {
584 		case DP_TRAINING_PATTERN_1:
585 			rtp = 0;
586 			break;
587 		case DP_TRAINING_PATTERN_2:
588 			rtp = 1;
589 			break;
590 		}
591 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_PATTERN_SEL,
592 					  dp_info->dp_clock, dp_info->enc_id, rtp);
593 	}
594 
595 	/* enable training pattern on the sink */
596 	drm_dp_dpcd_writeb(dp_info->aux, DP_TRAINING_PATTERN_SET, tp);
597 }
598 
599 static int radeon_dp_link_train_init(struct radeon_dp_link_train_info *dp_info)
600 {
601 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(dp_info->encoder);
602 	struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
603 	u8 tmp;
604 
605 	/* power up the sink */
606 	radeon_dp_set_rx_power_state(dp_info->connector, DP_SET_POWER_D0);
607 
608 	/* possibly enable downspread on the sink */
609 	if (dp_info->dpcd[3] & 0x1)
610 		drm_dp_dpcd_writeb(dp_info->aux,
611 				   DP_DOWNSPREAD_CTRL, DP_SPREAD_AMP_0_5);
612 	else
613 		drm_dp_dpcd_writeb(dp_info->aux,
614 				   DP_DOWNSPREAD_CTRL, 0);
615 
616 	if (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)
617 		drm_dp_dpcd_writeb(dp_info->aux, DP_EDP_CONFIGURATION_SET, 1);
618 
619 	/* set the lane count on the sink */
620 	tmp = dp_info->dp_lane_count;
621 	if (drm_dp_enhanced_frame_cap(dp_info->dpcd))
622 		tmp |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
623 	drm_dp_dpcd_writeb(dp_info->aux, DP_LANE_COUNT_SET, tmp);
624 
625 	/* set the link rate on the sink */
626 	tmp = drm_dp_link_rate_to_bw_code(dp_info->dp_clock);
627 	drm_dp_dpcd_writeb(dp_info->aux, DP_LINK_BW_SET, tmp);
628 
629 	/* start training on the source */
630 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
631 		atombios_dig_encoder_setup(dp_info->encoder,
632 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_START, 0);
633 	else
634 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_START,
635 					  dp_info->dp_clock, dp_info->enc_id, 0);
636 
637 	/* disable the training pattern on the sink */
638 	drm_dp_dpcd_writeb(dp_info->aux,
639 			   DP_TRAINING_PATTERN_SET,
640 			   DP_TRAINING_PATTERN_DISABLE);
641 
642 	return 0;
643 }
644 
645 static int radeon_dp_link_train_finish(struct radeon_dp_link_train_info *dp_info)
646 {
647 	udelay(400);
648 
649 	/* disable the training pattern on the sink */
650 	drm_dp_dpcd_writeb(dp_info->aux,
651 			   DP_TRAINING_PATTERN_SET,
652 			   DP_TRAINING_PATTERN_DISABLE);
653 
654 	/* disable the training pattern on the source */
655 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
656 		atombios_dig_encoder_setup(dp_info->encoder,
657 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_COMPLETE, 0);
658 	else
659 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_COMPLETE,
660 					  dp_info->dp_clock, dp_info->enc_id, 0);
661 
662 	return 0;
663 }
664 
665 static int radeon_dp_link_train_cr(struct radeon_dp_link_train_info *dp_info)
666 {
667 	bool clock_recovery;
668  	u8 voltage;
669 	int i;
670 
671 	radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_1);
672 	memset(dp_info->train_set, 0, 4);
673 	radeon_dp_update_vs_emph(dp_info);
674 
675 	udelay(400);
676 
677 	/* clock recovery loop */
678 	clock_recovery = false;
679 	dp_info->tries = 0;
680 	voltage = 0xff;
681 	while (1) {
682 		drm_dp_link_train_clock_recovery_delay(dp_info->dpcd);
683 
684 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
685 						 dp_info->link_status) <= 0) {
686 			DRM_ERROR("displayport link status failed\n");
687 			break;
688 		}
689 
690 		if (drm_dp_clock_recovery_ok(dp_info->link_status, dp_info->dp_lane_count)) {
691 			clock_recovery = true;
692 			break;
693 		}
694 
695 		for (i = 0; i < dp_info->dp_lane_count; i++) {
696 			if ((dp_info->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
697 				break;
698 		}
699 		if (i == dp_info->dp_lane_count) {
700 			DRM_ERROR("clock recovery reached max voltage\n");
701 			break;
702 		}
703 
704 		if ((dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
705 			++dp_info->tries;
706 			if (dp_info->tries == 5) {
707 				DRM_ERROR("clock recovery tried 5 times\n");
708 				break;
709 			}
710 		} else
711 			dp_info->tries = 0;
712 
713 		voltage = dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
714 
715 		/* Compute new train_set as requested by sink */
716 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
717 
718 		radeon_dp_update_vs_emph(dp_info);
719 	}
720 	if (!clock_recovery) {
721 		DRM_ERROR("clock recovery failed\n");
722 		return -1;
723 	} else {
724 		DRM_DEBUG_KMS("clock recovery at voltage %d pre-emphasis %d\n",
725 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
726 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK) >>
727 			  DP_TRAIN_PRE_EMPHASIS_SHIFT);
728 		return 0;
729 	}
730 }
731 
732 static int radeon_dp_link_train_ce(struct radeon_dp_link_train_info *dp_info)
733 {
734 	bool channel_eq;
735 
736 	if (dp_info->tp3_supported)
737 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_3);
738 	else
739 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_2);
740 
741 	/* channel equalization loop */
742 	dp_info->tries = 0;
743 	channel_eq = false;
744 	while (1) {
745 		drm_dp_link_train_channel_eq_delay(dp_info->dpcd);
746 
747 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
748 						 dp_info->link_status) <= 0) {
749 			DRM_ERROR("displayport link status failed\n");
750 			break;
751 		}
752 
753 		if (drm_dp_channel_eq_ok(dp_info->link_status, dp_info->dp_lane_count)) {
754 			channel_eq = true;
755 			break;
756 		}
757 
758 		/* Try 5 times */
759 		if (dp_info->tries > 5) {
760 			DRM_ERROR("channel eq failed: 5 tries\n");
761 			break;
762 		}
763 
764 		/* Compute new train_set as requested by sink */
765 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
766 
767 		radeon_dp_update_vs_emph(dp_info);
768 		dp_info->tries++;
769 	}
770 
771 	if (!channel_eq) {
772 		DRM_ERROR("channel eq failed\n");
773 		return -1;
774 	} else {
775 		DRM_DEBUG_KMS("channel eq at voltage %d pre-emphasis %d\n",
776 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
777 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK)
778 			  >> DP_TRAIN_PRE_EMPHASIS_SHIFT);
779 		return 0;
780 	}
781 }
782 
783 void radeon_dp_link_train(struct drm_encoder *encoder,
784 			  struct drm_connector *connector)
785 {
786 	struct drm_device *dev = encoder->dev;
787 	struct radeon_device *rdev = dev->dev_private;
788 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
789 	struct radeon_encoder_atom_dig *dig;
790 	struct radeon_connector *radeon_connector;
791 	struct radeon_connector_atom_dig *dig_connector;
792 	struct radeon_dp_link_train_info dp_info;
793 	int index;
794 	u8 tmp, frev, crev;
795 
796 	if (!radeon_encoder->enc_priv)
797 		return;
798 	dig = radeon_encoder->enc_priv;
799 
800 	radeon_connector = to_radeon_connector(connector);
801 	if (!radeon_connector->con_priv)
802 		return;
803 	dig_connector = radeon_connector->con_priv;
804 
805 	if ((dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_DISPLAYPORT) &&
806 	    (dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_eDP))
807 		return;
808 
809 	/* DPEncoderService newer than 1.1 can't program properly the
810 	 * training pattern. When facing such version use the
811 	 * DIGXEncoderControl (X== 1 | 2)
812 	 */
813 	dp_info.use_dpencoder = true;
814 	index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
815 	if (atom_parse_cmd_header(rdev->mode_info.atom_context, index, &frev, &crev)) {
816 		if (crev > 1)
817 			dp_info.use_dpencoder = false;
818 	}
819 
820 	dp_info.enc_id = 0;
821 	if (dig->dig_encoder)
822 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG2_ENCODER;
823 	else
824 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG1_ENCODER;
825 	if (dig->linkb)
826 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_B;
827 	else
828 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_A;
829 
830 	if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux, DP_MAX_LANE_COUNT, &tmp)
831 	    == 1) {
832 		if (ASIC_IS_DCE5(rdev) && (tmp & DP_TPS3_SUPPORTED))
833 			dp_info.tp3_supported = true;
834 		else
835 			dp_info.tp3_supported = false;
836 	} else {
837 		dp_info.tp3_supported = false;
838 	}
839 
840 	memcpy(dp_info.dpcd, dig_connector->dpcd, DP_RECEIVER_CAP_SIZE);
841 	dp_info.rdev = rdev;
842 	dp_info.encoder = encoder;
843 	dp_info.connector = connector;
844 	dp_info.dp_lane_count = dig_connector->dp_lane_count;
845 	dp_info.dp_clock = dig_connector->dp_clock;
846 	dp_info.aux = &radeon_connector->ddc_bus->aux;
847 
848 	if (radeon_dp_link_train_init(&dp_info))
849 		goto done;
850 	if (radeon_dp_link_train_cr(&dp_info))
851 		goto done;
852 	if (radeon_dp_link_train_ce(&dp_info))
853 		goto done;
854 done:
855 	if (radeon_dp_link_train_finish(&dp_info))
856 		return;
857 }
858