xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/radeon/radeon_atombios_dp.c (revision a04395531661c5e8d314125d5ae77d4cbedd5d73)
1 /*	$NetBSD: radeon_atombios_dp.c,v 1.3 2020/10/20 09:53:59 ryo Exp $	*/
2 
3 /*
4  * Copyright 2007-8 Advanced Micro Devices, Inc.
5  * Copyright 2008 Red Hat Inc.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a
8  * copy of this software and associated documentation files (the "Software"),
9  * to deal in the Software without restriction, including without limitation
10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11  * and/or sell copies of the Software, and to permit persons to whom the
12  * Software is furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23  * OTHER DEALINGS IN THE SOFTWARE.
24  *
25  * Authors: Dave Airlie
26  *          Alex Deucher
27  *          Jerome Glisse
28  */
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: radeon_atombios_dp.c,v 1.3 2020/10/20 09:53:59 ryo Exp $");
31 
32 #include <drm/drmP.h>
33 #include <drm/radeon_drm.h>
34 #include "radeon.h"
35 
36 #include "atom.h"
37 #include "atom-bits.h"
38 #include <drm/drm_dp_helper.h>
39 
40 #include <linux/nbsd-namespace.h>
41 
42 /* move these to drm_dp_helper.c/h */
43 #define DP_LINK_CONFIGURATION_SIZE 9
44 #define DP_DPCD_SIZE DP_RECEIVER_CAP_SIZE
45 
46 static const char *voltage_names[] = {
47         "0.4V", "0.6V", "0.8V", "1.2V"
48 };
49 static const char *pre_emph_names[] = {
50         "0dB", "3.5dB", "6dB", "9.5dB"
51 };
52 
53 /***** radeon AUX functions *****/
54 
55 /* Atom needs data in little endian format so swap as appropriate when copying
56  * data to or from atom. Note that atom operates on dw units.
57  *
58  * Use to_le=true when sending data to atom and provide at least
59  * ALIGN(num_bytes,4) bytes in the dst buffer.
60  *
61  * Use to_le=false when receiving data from atom and provide ALIGN(num_bytes,4)
62  * byes in the src buffer.
63  */
64 void radeon_atom_copy_swap(u8 *dst, u8 *src, u8 num_bytes, bool to_le)
65 {
66 #ifdef __BIG_ENDIAN
67 	u32 src_tmp[5], dst_tmp[5];
68 	int i;
69 	u8 align_num_bytes = ALIGN(num_bytes, 4);
70 
71 	if (to_le) {
72 		memcpy(src_tmp, src, num_bytes);
73 		for (i = 0; i < align_num_bytes / 4; i++)
74 			dst_tmp[i] = cpu_to_le32(src_tmp[i]);
75 		memcpy(dst, dst_tmp, align_num_bytes);
76 	} else {
77 		memcpy(src_tmp, src, align_num_bytes);
78 		for (i = 0; i < align_num_bytes / 4; i++)
79 			dst_tmp[i] = le32_to_cpu(src_tmp[i]);
80 		memcpy(dst, dst_tmp, num_bytes);
81 	}
82 #else
83 	memcpy(dst, src, num_bytes);
84 #endif
85 }
86 
87 union aux_channel_transaction {
88 	PROCESS_AUX_CHANNEL_TRANSACTION_PS_ALLOCATION v1;
89 	PROCESS_AUX_CHANNEL_TRANSACTION_PARAMETERS_V2 v2;
90 };
91 
92 static int radeon_process_aux_ch(struct radeon_i2c_chan *chan,
93 				 u8 *send, int send_bytes,
94 				 u8 *recv, int recv_size,
95 				 u8 delay, u8 *ack)
96 {
97 	struct drm_device *dev = chan->dev;
98 	struct radeon_device *rdev = dev->dev_private;
99 	union aux_channel_transaction args;
100 	int index = GetIndexIntoMasterTable(COMMAND, ProcessAuxChannelTransaction);
101 	unsigned char *base;
102 	int recv_bytes;
103 	int r = 0;
104 
105 	memset(&args, 0, sizeof(args));
106 
107 	mutex_lock(&chan->mutex);
108 	mutex_lock(&rdev->mode_info.atom_context->scratch_mutex);
109 
110 	base = (unsigned char *)(rdev->mode_info.atom_context->scratch + 1);
111 
112 	radeon_atom_copy_swap(base, send, send_bytes, true);
113 
114 	args.v1.lpAuxRequest = cpu_to_le16((u16)(0 + 4));
115 	args.v1.lpDataOut = cpu_to_le16((u16)(16 + 4));
116 	args.v1.ucDataOutLen = 0;
117 	args.v1.ucChannelID = chan->rec.i2c_id;
118 	args.v1.ucDelay = delay / 10;
119 	if (ASIC_IS_DCE4(rdev))
120 		args.v2.ucHPD_ID = chan->rec.hpd;
121 
122 	atom_execute_table_scratch_unlocked(rdev->mode_info.atom_context, index, (uint32_t *)&args);
123 
124 	*ack = args.v1.ucReplyStatus;
125 
126 	/* timeout */
127 	if (args.v1.ucReplyStatus == 1) {
128 		DRM_DEBUG_KMS("dp_aux_ch timeout\n");
129 		r = -ETIMEDOUT;
130 		goto done;
131 	}
132 
133 	/* flags not zero */
134 	if (args.v1.ucReplyStatus == 2) {
135 		DRM_DEBUG_KMS("dp_aux_ch flags not zero\n");
136 		r = -EIO;
137 		goto done;
138 	}
139 
140 	/* error */
141 	if (args.v1.ucReplyStatus == 3) {
142 		DRM_DEBUG_KMS("dp_aux_ch error\n");
143 		r = -EIO;
144 		goto done;
145 	}
146 
147 	recv_bytes = args.v1.ucDataOutLen;
148 	if (recv_bytes > recv_size)
149 		recv_bytes = recv_size;
150 
151 	if (recv && recv_size)
152 		radeon_atom_copy_swap(recv, base + 16, recv_bytes, false);
153 
154 	r = recv_bytes;
155 done:
156 	mutex_unlock(&rdev->mode_info.atom_context->scratch_mutex);
157 	mutex_unlock(&chan->mutex);
158 
159 	return r;
160 }
161 
162 #define BARE_ADDRESS_SIZE 3
163 #define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
164 
165 static ssize_t
166 radeon_dp_aux_transfer_atom(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
167 {
168 	struct radeon_i2c_chan *chan =
169 		container_of(aux, struct radeon_i2c_chan, aux);
170 	int ret;
171 	u8 tx_buf[20];
172 	size_t tx_size;
173 	u8 ack, delay = 0;
174 
175 	if (WARN_ON(msg->size > 16))
176 		return -E2BIG;
177 
178 	tx_buf[0] = msg->address & 0xff;
179 	tx_buf[1] = (msg->address >> 8) & 0xff;
180 	tx_buf[2] = (msg->request << 4) |
181 		((msg->address >> 16) & 0xf);
182 	tx_buf[3] = msg->size ? (msg->size - 1) : 0;
183 
184 	switch (msg->request & ~DP_AUX_I2C_MOT) {
185 	case DP_AUX_NATIVE_WRITE:
186 	case DP_AUX_I2C_WRITE:
187 	case DP_AUX_I2C_WRITE_STATUS_UPDATE:
188 		/* The atom implementation only supports writes with a max payload of
189 		 * 12 bytes since it uses 4 bits for the total count (header + payload)
190 		 * in the parameter space.  The atom interface supports 16 byte
191 		 * payloads for reads. The hw itself supports up to 16 bytes of payload.
192 		 */
193 		if (WARN_ON_ONCE(msg->size > 12))
194 			return -E2BIG;
195 		/* tx_size needs to be 4 even for bare address packets since the atom
196 		 * table needs the info in tx_buf[3].
197 		 */
198 		tx_size = HEADER_SIZE + msg->size;
199 		if (msg->size == 0)
200 			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
201 		else {
202 			tx_buf[3] |= tx_size << 4;
203 			memcpy(tx_buf + HEADER_SIZE, msg->buffer, msg->size);
204 		}
205 		ret = radeon_process_aux_ch(chan,
206 					    tx_buf, tx_size, NULL, 0, delay, &ack);
207 		if (ret >= 0)
208 			/* Return payload size. */
209 			ret = msg->size;
210 		break;
211 	case DP_AUX_NATIVE_READ:
212 	case DP_AUX_I2C_READ:
213 		/* tx_size needs to be 4 even for bare address packets since the atom
214 		 * table needs the info in tx_buf[3].
215 		 */
216 		tx_size = HEADER_SIZE;
217 		if (msg->size == 0)
218 			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
219 		else
220 			tx_buf[3] |= tx_size << 4;
221 		ret = radeon_process_aux_ch(chan,
222 					    tx_buf, tx_size, msg->buffer, msg->size, delay, &ack);
223 		break;
224 	default:
225 		ret = -EINVAL;
226 		break;
227 	}
228 
229 	if (ret >= 0)
230 		msg->reply = ack >> 4;
231 
232 	return ret;
233 }
234 
235 void radeon_dp_aux_init(struct radeon_connector *radeon_connector)
236 {
237 	struct drm_device *dev = radeon_connector->base.dev;
238 	struct radeon_device *rdev = dev->dev_private;
239 	int ret;
240 
241 	radeon_connector->ddc_bus->rec.hpd = radeon_connector->hpd.hpd;
242 	radeon_connector->ddc_bus->aux.dev = radeon_connector->base.kdev;
243 	if (ASIC_IS_DCE5(rdev)) {
244 		if (radeon_auxch)
245 			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_native;
246 		else
247 			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
248 	} else {
249 		radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
250 	}
251 
252 #ifdef __NetBSD__
253 	/* XXX dervied from sysfs/i2c on linux. */
254 	radeon_connector->ddc_bus->aux.name = "radeon_dp_aux";
255 #endif
256 
257 	ret = drm_dp_aux_register(&radeon_connector->ddc_bus->aux);
258 	if (!ret)
259 		radeon_connector->ddc_bus->has_aux = true;
260 
261 	WARN(ret, "drm_dp_aux_register() failed with error %d\n", ret);
262 }
263 
264 /***** general DP utility functions *****/
265 
266 #define DP_VOLTAGE_MAX         DP_TRAIN_VOLTAGE_SWING_LEVEL_3
267 #define DP_PRE_EMPHASIS_MAX    DP_TRAIN_PRE_EMPH_LEVEL_3
268 
269 static void dp_get_adjust_train(const u8 link_status[DP_LINK_STATUS_SIZE],
270 				int lane_count,
271 				u8 train_set[4])
272 {
273 	u8 v = 0;
274 	u8 p = 0;
275 	int lane;
276 
277 	for (lane = 0; lane < lane_count; lane++) {
278 		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
279 		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
280 
281 		DRM_DEBUG_KMS("requested signal parameters: lane %d voltage %s pre_emph %s\n",
282 			  lane,
283 			  voltage_names[this_v >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
284 			  pre_emph_names[this_p >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
285 
286 		if (this_v > v)
287 			v = this_v;
288 		if (this_p > p)
289 			p = this_p;
290 	}
291 
292 	if (v >= DP_VOLTAGE_MAX)
293 		v |= DP_TRAIN_MAX_SWING_REACHED;
294 
295 	if (p >= DP_PRE_EMPHASIS_MAX)
296 		p |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
297 
298 	DRM_DEBUG_KMS("using signal parameters: voltage %s pre_emph %s\n",
299 		  voltage_names[(v & DP_TRAIN_VOLTAGE_SWING_MASK) >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
300 		  pre_emph_names[(p & DP_TRAIN_PRE_EMPHASIS_MASK) >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
301 
302 	for (lane = 0; lane < 4; lane++)
303 		train_set[lane] = v | p;
304 }
305 
306 /* convert bits per color to bits per pixel */
307 /* get bpc from the EDID */
308 static int convert_bpc_to_bpp(int bpc)
309 {
310 	if (bpc == 0)
311 		return 24;
312 	else
313 		return bpc * 3;
314 }
315 
316 /***** radeon specific DP functions *****/
317 
318 int radeon_dp_get_dp_link_config(struct drm_connector *connector,
319 				 const u8 dpcd[DP_DPCD_SIZE],
320 				 unsigned pix_clock,
321 				 unsigned *dp_lanes, unsigned *dp_rate)
322 {
323 	int bpp = convert_bpc_to_bpp(radeon_get_monitor_bpc(connector));
324 	static const unsigned link_rates[3] = { 162000, 270000, 540000 };
325 	unsigned max_link_rate = drm_dp_max_link_rate(dpcd);
326 	unsigned max_lane_num = drm_dp_max_lane_count(dpcd);
327 	unsigned lane_num, i, max_pix_clock;
328 
329 	if (radeon_connector_encoder_get_dp_bridge_encoder_id(connector) ==
330 	    ENCODER_OBJECT_ID_NUTMEG) {
331 		for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
332 			max_pix_clock = (lane_num * 270000 * 8) / bpp;
333 			if (max_pix_clock >= pix_clock) {
334 				*dp_lanes = lane_num;
335 				*dp_rate = 270000;
336 				return 0;
337 			}
338 		}
339 	} else {
340 		for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) {
341 			for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
342 				max_pix_clock = (lane_num * link_rates[i] * 8) / bpp;
343 				if (max_pix_clock >= pix_clock) {
344 					*dp_lanes = lane_num;
345 					*dp_rate = link_rates[i];
346 					return 0;
347 				}
348 			}
349 		}
350 	}
351 
352 	return -EINVAL;
353 }
354 
355 static u8 radeon_dp_encoder_service(struct radeon_device *rdev,
356 				    int action, int dp_clock,
357 				    u8 ucconfig, u8 lane_num)
358 {
359 	DP_ENCODER_SERVICE_PARAMETERS args;
360 	int index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
361 
362 	memset(&args, 0, sizeof(args));
363 	args.ucLinkClock = dp_clock / 10;
364 	args.ucConfig = ucconfig;
365 	args.ucAction = action;
366 	args.ucLaneNum = lane_num;
367 	args.ucStatus = 0;
368 
369 	atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
370 	return args.ucStatus;
371 }
372 
373 u8 radeon_dp_getsinktype(struct radeon_connector *radeon_connector)
374 {
375 	struct drm_device *dev = radeon_connector->base.dev;
376 	struct radeon_device *rdev = dev->dev_private;
377 
378 	return radeon_dp_encoder_service(rdev, ATOM_DP_ACTION_GET_SINK_TYPE, 0,
379 					 radeon_connector->ddc_bus->rec.i2c_id, 0);
380 }
381 
382 static void radeon_dp_probe_oui(struct radeon_connector *radeon_connector)
383 {
384 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
385 	u8 buf[3];
386 
387 	if (!(dig_connector->dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
388 		return;
389 
390 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_SINK_OUI, buf, 3) == 3)
391 		DRM_DEBUG_KMS("Sink OUI: %02hhx%02hhx%02hhx\n",
392 			      buf[0], buf[1], buf[2]);
393 
394 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_BRANCH_OUI, buf, 3) == 3)
395 		DRM_DEBUG_KMS("Branch OUI: %02hhx%02hhx%02hhx\n",
396 			      buf[0], buf[1], buf[2]);
397 }
398 
399 bool radeon_dp_getdpcd(struct radeon_connector *radeon_connector)
400 {
401 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
402 	u8 msg[DP_DPCD_SIZE];
403 	int ret, i;
404 
405 	for (i = 0; i < 7; i++) {
406 		ret = drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_DPCD_REV, msg,
407 				       DP_DPCD_SIZE);
408 		if (ret == DP_DPCD_SIZE) {
409 			memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE);
410 
411 			DRM_DEBUG_KMS("DPCD: %*ph\n", (int)sizeof(dig_connector->dpcd),
412 				      dig_connector->dpcd);
413 
414 			radeon_dp_probe_oui(radeon_connector);
415 
416 			return true;
417 		}
418 	}
419 	dig_connector->dpcd[0] = 0;
420 	return false;
421 }
422 
423 int radeon_dp_get_panel_mode(struct drm_encoder *encoder,
424 			     struct drm_connector *connector)
425 {
426 	struct drm_device *dev = encoder->dev;
427 	struct radeon_device *rdev = dev->dev_private;
428 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
429 	int panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
430 	u16 dp_bridge = radeon_connector_encoder_get_dp_bridge_encoder_id(connector);
431 	u8 tmp;
432 
433 	if (!ASIC_IS_DCE4(rdev))
434 		return panel_mode;
435 
436 	if (!radeon_connector->con_priv)
437 		return panel_mode;
438 
439 	if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
440 		/* DP bridge chips */
441 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
442 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
443 			if (tmp & 1)
444 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
445 			else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
446 				 (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
447 				panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
448 			else
449 				panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
450 		}
451 	} else if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
452 		/* eDP */
453 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
454 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
455 			if (tmp & 1)
456 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
457 		}
458 	}
459 
460 	return panel_mode;
461 }
462 
463 void radeon_dp_set_link_config(struct drm_connector *connector,
464 			       const struct drm_display_mode *mode)
465 {
466 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
467 	struct radeon_connector_atom_dig *dig_connector;
468 	int ret;
469 
470 	if (!radeon_connector->con_priv)
471 		return;
472 	dig_connector = radeon_connector->con_priv;
473 
474 	if ((dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) ||
475 	    (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_eDP)) {
476 		ret = radeon_dp_get_dp_link_config(connector, dig_connector->dpcd,
477 						   mode->clock,
478 						   &dig_connector->dp_lane_count,
479 						   &dig_connector->dp_clock);
480 		if (ret) {
481 			dig_connector->dp_clock = 0;
482 			dig_connector->dp_lane_count = 0;
483 		}
484 	}
485 }
486 
487 int radeon_dp_mode_valid_helper(struct drm_connector *connector,
488 				struct drm_display_mode *mode)
489 {
490 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
491 	struct radeon_connector_atom_dig *dig_connector;
492 	unsigned dp_clock, dp_lanes;
493 	int ret;
494 
495 	if ((mode->clock > 340000) &&
496 	    (!radeon_connector_is_dp12_capable(connector)))
497 		return MODE_CLOCK_HIGH;
498 
499 	if (!radeon_connector->con_priv)
500 		return MODE_CLOCK_HIGH;
501 	dig_connector = radeon_connector->con_priv;
502 
503 	ret = radeon_dp_get_dp_link_config(connector, dig_connector->dpcd,
504 					   mode->clock,
505 					   &dp_lanes,
506 					   &dp_clock);
507 	if (ret)
508 		return MODE_CLOCK_HIGH;
509 
510 	if ((dp_clock == 540000) &&
511 	    (!radeon_connector_is_dp12_capable(connector)))
512 		return MODE_CLOCK_HIGH;
513 
514 	return MODE_OK;
515 }
516 
517 bool radeon_dp_needs_link_train(struct radeon_connector *radeon_connector)
518 {
519 	u8 link_status[DP_LINK_STATUS_SIZE];
520 	struct radeon_connector_atom_dig *dig = radeon_connector->con_priv;
521 
522 	if (drm_dp_dpcd_read_link_status(&radeon_connector->ddc_bus->aux, link_status)
523 	    <= 0)
524 		return false;
525 	if (drm_dp_channel_eq_ok(link_status, dig->dp_lane_count))
526 		return false;
527 	return true;
528 }
529 
530 void radeon_dp_set_rx_power_state(struct drm_connector *connector,
531 				  u8 power_state)
532 {
533 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
534 	struct radeon_connector_atom_dig *dig_connector;
535 
536 	if (!radeon_connector->con_priv)
537 		return;
538 
539 	dig_connector = radeon_connector->con_priv;
540 
541 	/* power up/down the sink */
542 	if (dig_connector->dpcd[0] >= 0x11) {
543 		drm_dp_dpcd_writeb(&radeon_connector->ddc_bus->aux,
544 				   DP_SET_POWER, power_state);
545 		usleep_range(1000, 2000);
546 	}
547 }
548 
549 
550 struct radeon_dp_link_train_info {
551 	struct radeon_device *rdev;
552 	struct drm_encoder *encoder;
553 	struct drm_connector *connector;
554 	int enc_id;
555 	int dp_clock;
556 	int dp_lane_count;
557 	bool tp3_supported;
558 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
559 	u8 train_set[4];
560 	u8 link_status[DP_LINK_STATUS_SIZE];
561 	u8 tries;
562 	bool use_dpencoder;
563 	struct drm_dp_aux *aux;
564 };
565 
566 static void radeon_dp_update_vs_emph(struct radeon_dp_link_train_info *dp_info)
567 {
568 	/* set the initial vs/emph on the source */
569 	atombios_dig_transmitter_setup(dp_info->encoder,
570 				       ATOM_TRANSMITTER_ACTION_SETUP_VSEMPH,
571 				       0, dp_info->train_set[0]); /* sets all lanes at once */
572 
573 	/* set the vs/emph on the sink */
574 	drm_dp_dpcd_write(dp_info->aux, DP_TRAINING_LANE0_SET,
575 			  dp_info->train_set, dp_info->dp_lane_count);
576 }
577 
578 static void radeon_dp_set_tp(struct radeon_dp_link_train_info *dp_info, int tp)
579 {
580 	int rtp = 0;
581 
582 	/* set training pattern on the source */
583 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder) {
584 		switch (tp) {
585 		case DP_TRAINING_PATTERN_1:
586 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN1;
587 			break;
588 		case DP_TRAINING_PATTERN_2:
589 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN2;
590 			break;
591 		case DP_TRAINING_PATTERN_3:
592 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN3;
593 			break;
594 		}
595 		atombios_dig_encoder_setup(dp_info->encoder, rtp, 0);
596 	} else {
597 		switch (tp) {
598 		case DP_TRAINING_PATTERN_1:
599 			rtp = 0;
600 			break;
601 		case DP_TRAINING_PATTERN_2:
602 			rtp = 1;
603 			break;
604 		}
605 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_PATTERN_SEL,
606 					  dp_info->dp_clock, dp_info->enc_id, rtp);
607 	}
608 
609 	/* enable training pattern on the sink */
610 	drm_dp_dpcd_writeb(dp_info->aux, DP_TRAINING_PATTERN_SET, tp);
611 }
612 
613 static int radeon_dp_link_train_init(struct radeon_dp_link_train_info *dp_info)
614 {
615 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(dp_info->encoder);
616 	struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
617 	u8 tmp;
618 
619 	/* power up the sink */
620 	radeon_dp_set_rx_power_state(dp_info->connector, DP_SET_POWER_D0);
621 
622 	/* possibly enable downspread on the sink */
623 	if (dp_info->dpcd[3] & 0x1)
624 		drm_dp_dpcd_writeb(dp_info->aux,
625 				   DP_DOWNSPREAD_CTRL, DP_SPREAD_AMP_0_5);
626 	else
627 		drm_dp_dpcd_writeb(dp_info->aux,
628 				   DP_DOWNSPREAD_CTRL, 0);
629 
630 	if (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)
631 		drm_dp_dpcd_writeb(dp_info->aux, DP_EDP_CONFIGURATION_SET, 1);
632 
633 	/* set the lane count on the sink */
634 	tmp = dp_info->dp_lane_count;
635 	if (drm_dp_enhanced_frame_cap(dp_info->dpcd))
636 		tmp |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
637 	drm_dp_dpcd_writeb(dp_info->aux, DP_LANE_COUNT_SET, tmp);
638 
639 	/* set the link rate on the sink */
640 	tmp = drm_dp_link_rate_to_bw_code(dp_info->dp_clock);
641 	drm_dp_dpcd_writeb(dp_info->aux, DP_LINK_BW_SET, tmp);
642 
643 	/* start training on the source */
644 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
645 		atombios_dig_encoder_setup(dp_info->encoder,
646 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_START, 0);
647 	else
648 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_START,
649 					  dp_info->dp_clock, dp_info->enc_id, 0);
650 
651 	/* disable the training pattern on the sink */
652 	drm_dp_dpcd_writeb(dp_info->aux,
653 			   DP_TRAINING_PATTERN_SET,
654 			   DP_TRAINING_PATTERN_DISABLE);
655 
656 	return 0;
657 }
658 
659 static int radeon_dp_link_train_finish(struct radeon_dp_link_train_info *dp_info)
660 {
661 	udelay(400);
662 
663 	/* disable the training pattern on the sink */
664 	drm_dp_dpcd_writeb(dp_info->aux,
665 			   DP_TRAINING_PATTERN_SET,
666 			   DP_TRAINING_PATTERN_DISABLE);
667 
668 	/* disable the training pattern on the source */
669 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
670 		atombios_dig_encoder_setup(dp_info->encoder,
671 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_COMPLETE, 0);
672 	else
673 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_COMPLETE,
674 					  dp_info->dp_clock, dp_info->enc_id, 0);
675 
676 	return 0;
677 }
678 
679 static int radeon_dp_link_train_cr(struct radeon_dp_link_train_info *dp_info)
680 {
681 	bool clock_recovery;
682  	u8 voltage;
683 	int i;
684 
685 	radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_1);
686 	memset(dp_info->train_set, 0, 4);
687 	radeon_dp_update_vs_emph(dp_info);
688 
689 	udelay(400);
690 
691 	/* clock recovery loop */
692 	clock_recovery = false;
693 	dp_info->tries = 0;
694 	voltage = 0xff;
695 	while (1) {
696 		drm_dp_link_train_clock_recovery_delay(dp_info->dpcd);
697 
698 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
699 						 dp_info->link_status) <= 0) {
700 			DRM_ERROR("displayport link status failed\n");
701 			break;
702 		}
703 
704 		if (drm_dp_clock_recovery_ok(dp_info->link_status, dp_info->dp_lane_count)) {
705 			clock_recovery = true;
706 			break;
707 		}
708 
709 		for (i = 0; i < dp_info->dp_lane_count; i++) {
710 			if ((dp_info->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
711 				break;
712 		}
713 		if (i == dp_info->dp_lane_count) {
714 			DRM_ERROR("clock recovery reached max voltage\n");
715 			break;
716 		}
717 
718 		if ((dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
719 			++dp_info->tries;
720 			if (dp_info->tries == 5) {
721 				DRM_ERROR("clock recovery tried 5 times\n");
722 				break;
723 			}
724 		} else
725 			dp_info->tries = 0;
726 
727 		voltage = dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
728 
729 		/* Compute new train_set as requested by sink */
730 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
731 
732 		radeon_dp_update_vs_emph(dp_info);
733 	}
734 	if (!clock_recovery) {
735 		DRM_ERROR("clock recovery failed\n");
736 		return -1;
737 	} else {
738 		DRM_DEBUG_KMS("clock recovery at voltage %d pre-emphasis %d\n",
739 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
740 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK) >>
741 			  DP_TRAIN_PRE_EMPHASIS_SHIFT);
742 		return 0;
743 	}
744 }
745 
746 static int radeon_dp_link_train_ce(struct radeon_dp_link_train_info *dp_info)
747 {
748 	bool channel_eq;
749 
750 	if (dp_info->tp3_supported)
751 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_3);
752 	else
753 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_2);
754 
755 	/* channel equalization loop */
756 	dp_info->tries = 0;
757 	channel_eq = false;
758 	while (1) {
759 		drm_dp_link_train_channel_eq_delay(dp_info->dpcd);
760 
761 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
762 						 dp_info->link_status) <= 0) {
763 			DRM_ERROR("displayport link status failed\n");
764 			break;
765 		}
766 
767 		if (drm_dp_channel_eq_ok(dp_info->link_status, dp_info->dp_lane_count)) {
768 			channel_eq = true;
769 			break;
770 		}
771 
772 		/* Try 5 times */
773 		if (dp_info->tries > 5) {
774 			DRM_ERROR("channel eq failed: 5 tries\n");
775 			break;
776 		}
777 
778 		/* Compute new train_set as requested by sink */
779 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
780 
781 		radeon_dp_update_vs_emph(dp_info);
782 		dp_info->tries++;
783 	}
784 
785 	if (!channel_eq) {
786 		DRM_ERROR("channel eq failed\n");
787 		return -1;
788 	} else {
789 		DRM_DEBUG_KMS("channel eq at voltage %d pre-emphasis %d\n",
790 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
791 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK)
792 			  >> DP_TRAIN_PRE_EMPHASIS_SHIFT);
793 		return 0;
794 	}
795 }
796 
797 void radeon_dp_link_train(struct drm_encoder *encoder,
798 			  struct drm_connector *connector)
799 {
800 	struct drm_device *dev = encoder->dev;
801 	struct radeon_device *rdev = dev->dev_private;
802 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
803 	struct radeon_encoder_atom_dig *dig;
804 	struct radeon_connector *radeon_connector;
805 	struct radeon_connector_atom_dig *dig_connector;
806 	struct radeon_dp_link_train_info dp_info;
807 	int index;
808 	u8 tmp, frev, crev;
809 
810 	if (!radeon_encoder->enc_priv)
811 		return;
812 	dig = radeon_encoder->enc_priv;
813 
814 	radeon_connector = to_radeon_connector(connector);
815 	if (!radeon_connector->con_priv)
816 		return;
817 	dig_connector = radeon_connector->con_priv;
818 
819 	if ((dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_DISPLAYPORT) &&
820 	    (dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_eDP))
821 		return;
822 
823 	/* DPEncoderService newer than 1.1 can't program properly the
824 	 * training pattern. When facing such version use the
825 	 * DIGXEncoderControl (X== 1 | 2)
826 	 */
827 	dp_info.use_dpencoder = true;
828 	index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
829 	if (atom_parse_cmd_header(rdev->mode_info.atom_context, index, &frev, &crev)) {
830 		if (crev > 1) {
831 			dp_info.use_dpencoder = false;
832 		}
833 	}
834 
835 	dp_info.enc_id = 0;
836 	if (dig->dig_encoder)
837 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG2_ENCODER;
838 	else
839 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG1_ENCODER;
840 	if (dig->linkb)
841 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_B;
842 	else
843 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_A;
844 
845 	if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux, DP_MAX_LANE_COUNT, &tmp)
846 	    == 1) {
847 		if (ASIC_IS_DCE5(rdev) && (tmp & DP_TPS3_SUPPORTED))
848 			dp_info.tp3_supported = true;
849 		else
850 			dp_info.tp3_supported = false;
851 	} else {
852 		dp_info.tp3_supported = false;
853 	}
854 
855 	memcpy(dp_info.dpcd, dig_connector->dpcd, DP_RECEIVER_CAP_SIZE);
856 	dp_info.rdev = rdev;
857 	dp_info.encoder = encoder;
858 	dp_info.connector = connector;
859 	dp_info.dp_lane_count = dig_connector->dp_lane_count;
860 	dp_info.dp_clock = dig_connector->dp_clock;
861 	dp_info.aux = &radeon_connector->ddc_bus->aux;
862 
863 	if (radeon_dp_link_train_init(&dp_info))
864 		goto done;
865 	if (radeon_dp_link_train_cr(&dp_info))
866 		goto done;
867 	if (radeon_dp_link_train_ce(&dp_info))
868 		goto done;
869 done:
870 	if (radeon_dp_link_train_finish(&dp_info))
871 		return;
872 }
873