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 	mutex_lock(&rdev->mode_info.atom_context->scratch_mutex);
104 
105 	base = (unsigned char *)(rdev->mode_info.atom_context->scratch + 1);
106 
107 	radeon_atom_copy_swap(base, send, send_bytes, true);
108 
109 	args.v1.lpAuxRequest = cpu_to_le16((u16)(0 + 4));
110 	args.v1.lpDataOut = cpu_to_le16((u16)(16 + 4));
111 	args.v1.ucDataOutLen = 0;
112 	args.v1.ucChannelID = chan->rec.i2c_id;
113 	args.v1.ucDelay = delay / 10;
114 	if (ASIC_IS_DCE4(rdev))
115 		args.v2.ucHPD_ID = chan->rec.hpd;
116 
117 	atom_execute_table_scratch_unlocked(rdev->mode_info.atom_context, index, (uint32_t *)&args);
118 
119 	*ack = args.v1.ucReplyStatus;
120 
121 	/* timeout */
122 	if (args.v1.ucReplyStatus == 1) {
123 		DRM_DEBUG_KMS("dp_aux_ch timeout\n");
124 		r = -ETIMEDOUT;
125 		goto done;
126 	}
127 
128 	/* flags not zero */
129 	if (args.v1.ucReplyStatus == 2) {
130 		DRM_DEBUG_KMS("dp_aux_ch flags not zero\n");
131 		r = -EIO;
132 		goto done;
133 	}
134 
135 	/* error */
136 	if (args.v1.ucReplyStatus == 3) {
137 		DRM_DEBUG_KMS("dp_aux_ch error\n");
138 		r = -EIO;
139 		goto done;
140 	}
141 
142 	recv_bytes = args.v1.ucDataOutLen;
143 	if (recv_bytes > recv_size)
144 		recv_bytes = recv_size;
145 
146 	if (recv && recv_size)
147 		radeon_atom_copy_swap(recv, base + 16, recv_bytes, false);
148 
149 	r = recv_bytes;
150 done:
151 	mutex_unlock(&rdev->mode_info.atom_context->scratch_mutex);
152 	mutex_unlock(&chan->mutex);
153 
154 	return r;
155 }
156 
157 #define BARE_ADDRESS_SIZE 3
158 #define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
159 
160 static ssize_t
161 radeon_dp_aux_transfer_atom(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
162 {
163 	struct radeon_i2c_chan *chan =
164 		container_of(aux, struct radeon_i2c_chan, aux);
165 	int ret;
166 	u8 tx_buf[20];
167 	size_t tx_size;
168 	u8 ack, delay = 0;
169 
170 	if (WARN_ON(msg->size > 16))
171 		return -E2BIG;
172 
173 	tx_buf[0] = msg->address & 0xff;
174 	tx_buf[1] = (msg->address >> 8) & 0xff;
175 	tx_buf[2] = (msg->request << 4) |
176 		((msg->address >> 16) & 0xf);
177 	tx_buf[3] = msg->size ? (msg->size - 1) : 0;
178 
179 	switch (msg->request & ~DP_AUX_I2C_MOT) {
180 	case DP_AUX_NATIVE_WRITE:
181 	case DP_AUX_I2C_WRITE:
182 		/* The atom implementation only supports writes with a max payload of
183 		 * 12 bytes since it uses 4 bits for the total count (header + payload)
184 		 * in the parameter space.  The atom interface supports 16 byte
185 		 * payloads for reads. The hw itself supports up to 16 bytes of payload.
186 		 */
187 		if (WARN_ON_ONCE(msg->size > 12))
188 			return -E2BIG;
189 		/* tx_size needs to be 4 even for bare address packets since the atom
190 		 * table needs the info in tx_buf[3].
191 		 */
192 		tx_size = HEADER_SIZE + msg->size;
193 		if (msg->size == 0)
194 			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
195 		else
196 			tx_buf[3] |= tx_size << 4;
197 		memcpy(tx_buf + HEADER_SIZE, msg->buffer, msg->size);
198 		ret = radeon_process_aux_ch(chan,
199 					    tx_buf, tx_size, NULL, 0, delay, &ack);
200 		if (ret >= 0)
201 			/* Return payload size. */
202 			ret = msg->size;
203 		break;
204 	case DP_AUX_NATIVE_READ:
205 	case DP_AUX_I2C_READ:
206 		/* tx_size needs to be 4 even for bare address packets since the atom
207 		 * table needs the info in tx_buf[3].
208 		 */
209 		tx_size = HEADER_SIZE;
210 		if (msg->size == 0)
211 			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
212 		else
213 			tx_buf[3] |= tx_size << 4;
214 		ret = radeon_process_aux_ch(chan,
215 					    tx_buf, tx_size, msg->buffer, msg->size, delay, &ack);
216 		break;
217 	default:
218 		ret = -EINVAL;
219 		break;
220 	}
221 
222 	if (ret >= 0)
223 		msg->reply = ack >> 4;
224 
225 	return ret;
226 }
227 
228 void radeon_dp_aux_init(struct radeon_connector *radeon_connector)
229 {
230 	struct drm_device *dev = radeon_connector->base.dev;
231 	struct radeon_device *rdev = dev->dev_private;
232 	int ret;
233 
234 	radeon_connector->ddc_bus->rec.hpd = radeon_connector->hpd.hpd;
235 	radeon_connector->ddc_bus->aux.dev = radeon_connector->base.kdev;
236 	if (ASIC_IS_DCE5(rdev)) {
237 		if (radeon_auxch)
238 			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_native;
239 		else
240 			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
241 	} else {
242 		radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
243 	}
244 
245 	ret = drm_dp_aux_register(&radeon_connector->ddc_bus->aux);
246 	if (!ret)
247 		radeon_connector->ddc_bus->has_aux = true;
248 
249 	WARN(ret, "drm_dp_aux_register() failed with error %d\n", ret);
250 }
251 
252 /***** general DP utility functions *****/
253 
254 #define DP_VOLTAGE_MAX         DP_TRAIN_VOLTAGE_SWING_LEVEL_3
255 #define DP_PRE_EMPHASIS_MAX    DP_TRAIN_PRE_EMPH_LEVEL_3
256 
257 static void dp_get_adjust_train(const u8 link_status[DP_LINK_STATUS_SIZE],
258 				int lane_count,
259 				u8 train_set[4])
260 {
261 	u8 v = 0;
262 	u8 p = 0;
263 	int lane;
264 
265 	for (lane = 0; lane < lane_count; lane++) {
266 		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
267 		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
268 
269 		DRM_DEBUG_KMS("requested signal parameters: lane %d voltage %s pre_emph %s\n",
270 			  lane,
271 			  voltage_names[this_v >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
272 			  pre_emph_names[this_p >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
273 
274 		if (this_v > v)
275 			v = this_v;
276 		if (this_p > p)
277 			p = this_p;
278 	}
279 
280 	if (v >= DP_VOLTAGE_MAX)
281 		v |= DP_TRAIN_MAX_SWING_REACHED;
282 
283 	if (p >= DP_PRE_EMPHASIS_MAX)
284 		p |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
285 
286 	DRM_DEBUG_KMS("using signal parameters: voltage %s pre_emph %s\n",
287 		  voltage_names[(v & DP_TRAIN_VOLTAGE_SWING_MASK) >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
288 		  pre_emph_names[(p & DP_TRAIN_PRE_EMPHASIS_MASK) >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
289 
290 	for (lane = 0; lane < 4; lane++)
291 		train_set[lane] = v | p;
292 }
293 
294 /* convert bits per color to bits per pixel */
295 /* get bpc from the EDID */
296 static int convert_bpc_to_bpp(int bpc)
297 {
298 	if (bpc == 0)
299 		return 24;
300 	else
301 		return bpc * 3;
302 }
303 
304 /* get the max pix clock supported by the link rate and lane num */
305 static int dp_get_max_dp_pix_clock(int link_rate,
306 				   int lane_num,
307 				   int bpp)
308 {
309 	return (link_rate * lane_num * 8) / bpp;
310 }
311 
312 /***** radeon specific DP functions *****/
313 
314 int radeon_dp_get_max_link_rate(struct drm_connector *connector,
315 				const u8 dpcd[DP_DPCD_SIZE])
316 {
317 	int max_link_rate;
318 
319 	if (radeon_connector_is_dp12_capable(connector))
320 		max_link_rate = min(drm_dp_max_link_rate(dpcd), 540000);
321 	else
322 		max_link_rate = min(drm_dp_max_link_rate(dpcd), 270000);
323 
324 	return max_link_rate;
325 }
326 
327 /* First get the min lane# when low rate is used according to pixel clock
328  * (prefer low rate), second check max lane# supported by DP panel,
329  * if the max lane# < low rate lane# then use max lane# instead.
330  */
331 static int radeon_dp_get_dp_lane_number(struct drm_connector *connector,
332 					const u8 dpcd[DP_DPCD_SIZE],
333 					int pix_clock)
334 {
335 	int bpp = convert_bpc_to_bpp(radeon_get_monitor_bpc(connector));
336 	int max_link_rate = radeon_dp_get_max_link_rate(connector, dpcd);
337 	int max_lane_num = drm_dp_max_lane_count(dpcd);
338 	int lane_num;
339 	int max_dp_pix_clock;
340 
341 	for (lane_num = 1; lane_num < max_lane_num; lane_num <<= 1) {
342 		max_dp_pix_clock = dp_get_max_dp_pix_clock(max_link_rate, lane_num, bpp);
343 		if (pix_clock <= max_dp_pix_clock)
344 			break;
345 	}
346 
347 	return lane_num;
348 }
349 
350 static int radeon_dp_get_dp_link_clock(struct drm_connector *connector,
351 				       const u8 dpcd[DP_DPCD_SIZE],
352 				       int pix_clock)
353 {
354 	int bpp = convert_bpc_to_bpp(radeon_get_monitor_bpc(connector));
355 	int lane_num, max_pix_clock;
356 
357 	if (radeon_connector_encoder_get_dp_bridge_encoder_id(connector) ==
358 	    ENCODER_OBJECT_ID_NUTMEG)
359 		return 270000;
360 
361 	lane_num = radeon_dp_get_dp_lane_number(connector, dpcd, pix_clock);
362 	max_pix_clock = dp_get_max_dp_pix_clock(162000, lane_num, bpp);
363 	if (pix_clock <= max_pix_clock)
364 		return 162000;
365 	max_pix_clock = dp_get_max_dp_pix_clock(270000, lane_num, bpp);
366 	if (pix_clock <= max_pix_clock)
367 		return 270000;
368 	if (radeon_connector_is_dp12_capable(connector)) {
369 		max_pix_clock = dp_get_max_dp_pix_clock(540000, lane_num, bpp);
370 		if (pix_clock <= max_pix_clock)
371 			return 540000;
372 	}
373 
374 	return radeon_dp_get_max_link_rate(connector, dpcd);
375 }
376 
377 static u8 radeon_dp_encoder_service(struct radeon_device *rdev,
378 				    int action, int dp_clock,
379 				    u8 ucconfig, u8 lane_num)
380 {
381 	DP_ENCODER_SERVICE_PARAMETERS args;
382 	int index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
383 
384 	memset(&args, 0, sizeof(args));
385 	args.ucLinkClock = dp_clock / 10;
386 	args.ucConfig = ucconfig;
387 	args.ucAction = action;
388 	args.ucLaneNum = lane_num;
389 	args.ucStatus = 0;
390 
391 	atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
392 	return args.ucStatus;
393 }
394 
395 u8 radeon_dp_getsinktype(struct radeon_connector *radeon_connector)
396 {
397 	struct drm_device *dev = radeon_connector->base.dev;
398 	struct radeon_device *rdev = dev->dev_private;
399 
400 	return radeon_dp_encoder_service(rdev, ATOM_DP_ACTION_GET_SINK_TYPE, 0,
401 					 radeon_connector->ddc_bus->rec.i2c_id, 0);
402 }
403 
404 static void radeon_dp_probe_oui(struct radeon_connector *radeon_connector)
405 {
406 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
407 	u8 buf[3];
408 
409 	if (!(dig_connector->dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
410 		return;
411 
412 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_SINK_OUI, buf, 3) == 3)
413 		DRM_DEBUG_KMS("Sink OUI: %02hx%02hx%02hx\n",
414 			      buf[0], buf[1], buf[2]);
415 
416 	if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_BRANCH_OUI, buf, 3) == 3)
417 		DRM_DEBUG_KMS("Branch OUI: %02hx%02hx%02hx\n",
418 			      buf[0], buf[1], buf[2]);
419 }
420 
421 bool radeon_dp_getdpcd(struct radeon_connector *radeon_connector)
422 {
423 	struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv;
424 	u8 msg[DP_DPCD_SIZE];
425 	int ret, i;
426 
427 	for (i = 0; i < 7; i++) {
428 		ret = drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux, DP_DPCD_REV, msg,
429 				       DP_DPCD_SIZE);
430 		if (ret == DP_DPCD_SIZE) {
431 			memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE);
432 
433 			DRM_DEBUG_KMS("DPCD: %*ph\n", (int)sizeof(dig_connector->dpcd),
434 				      dig_connector->dpcd);
435 
436 			radeon_dp_probe_oui(radeon_connector);
437 
438 			return true;
439 		}
440 	}
441 	dig_connector->dpcd[0] = 0;
442 	return false;
443 }
444 
445 int radeon_dp_get_panel_mode(struct drm_encoder *encoder,
446 			     struct drm_connector *connector)
447 {
448 	struct drm_device *dev = encoder->dev;
449 	struct radeon_device *rdev = dev->dev_private;
450 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
451 	struct radeon_connector_atom_dig *dig_connector;
452 	int panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
453 	u16 dp_bridge = radeon_connector_encoder_get_dp_bridge_encoder_id(connector);
454 	u8 tmp;
455 
456 	if (!ASIC_IS_DCE4(rdev))
457 		return panel_mode;
458 
459 	if (!radeon_connector->con_priv)
460 		return panel_mode;
461 
462 	dig_connector = radeon_connector->con_priv;
463 
464 	if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
465 		/* DP bridge chips */
466 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
467 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
468 			if (tmp & 1)
469 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
470 			else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
471 				 (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
472 				panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
473 			else
474 				panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
475 		}
476 	} else if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
477 		/* eDP */
478 		if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
479 				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
480 			if (tmp & 1)
481 				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
482 		}
483 	}
484 
485 	return panel_mode;
486 }
487 
488 void radeon_dp_set_link_config(struct drm_connector *connector,
489 			       const struct drm_display_mode *mode)
490 {
491 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
492 	struct radeon_connector_atom_dig *dig_connector;
493 
494 	if (!radeon_connector->con_priv)
495 		return;
496 	dig_connector = radeon_connector->con_priv;
497 
498 	if ((dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) ||
499 	    (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_eDP)) {
500 		dig_connector->dp_clock =
501 			radeon_dp_get_dp_link_clock(connector, dig_connector->dpcd, mode->clock);
502 		dig_connector->dp_lane_count =
503 			radeon_dp_get_dp_lane_number(connector, dig_connector->dpcd, mode->clock);
504 	}
505 }
506 
507 int radeon_dp_mode_valid_helper(struct drm_connector *connector,
508 				struct drm_display_mode *mode)
509 {
510 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
511 	struct radeon_connector_atom_dig *dig_connector;
512 	int dp_clock;
513 
514 	if ((mode->clock > 340000) &&
515 	    (!radeon_connector_is_dp12_capable(connector)))
516 		return MODE_CLOCK_HIGH;
517 
518 	if (!radeon_connector->con_priv)
519 		return MODE_CLOCK_HIGH;
520 	dig_connector = radeon_connector->con_priv;
521 
522 	dp_clock =
523 		radeon_dp_get_dp_link_clock(connector, dig_connector->dpcd, mode->clock);
524 
525 	if ((dp_clock == 540000) &&
526 	    (!radeon_connector_is_dp12_capable(connector)))
527 		return MODE_CLOCK_HIGH;
528 
529 	return MODE_OK;
530 }
531 
532 bool radeon_dp_needs_link_train(struct radeon_connector *radeon_connector)
533 {
534 	u8 link_status[DP_LINK_STATUS_SIZE];
535 	struct radeon_connector_atom_dig *dig = radeon_connector->con_priv;
536 
537 	if (drm_dp_dpcd_read_link_status(&radeon_connector->ddc_bus->aux, link_status)
538 	    <= 0)
539 		return false;
540 	if (drm_dp_channel_eq_ok(link_status, dig->dp_lane_count))
541 		return false;
542 	return true;
543 }
544 
545 void radeon_dp_set_rx_power_state(struct drm_connector *connector,
546 				  u8 power_state)
547 {
548 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
549 	struct radeon_connector_atom_dig *dig_connector;
550 
551 	if (!radeon_connector->con_priv)
552 		return;
553 
554 	dig_connector = radeon_connector->con_priv;
555 
556 	/* power up/down the sink */
557 	if (dig_connector->dpcd[0] >= 0x11) {
558 		drm_dp_dpcd_writeb(&radeon_connector->ddc_bus->aux,
559 				   DP_SET_POWER, power_state);
560 		usleep_range(1000, 2000);
561 	}
562 }
563 
564 
565 struct radeon_dp_link_train_info {
566 	struct radeon_device *rdev;
567 	struct drm_encoder *encoder;
568 	struct drm_connector *connector;
569 	int enc_id;
570 	int dp_clock;
571 	int dp_lane_count;
572 	bool tp3_supported;
573 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
574 	u8 train_set[4];
575 	u8 link_status[DP_LINK_STATUS_SIZE];
576 	u8 tries;
577 	bool use_dpencoder;
578 	struct drm_dp_aux *aux;
579 };
580 
581 static void radeon_dp_update_vs_emph(struct radeon_dp_link_train_info *dp_info)
582 {
583 	/* set the initial vs/emph on the source */
584 	atombios_dig_transmitter_setup(dp_info->encoder,
585 				       ATOM_TRANSMITTER_ACTION_SETUP_VSEMPH,
586 				       0, dp_info->train_set[0]); /* sets all lanes at once */
587 
588 	/* set the vs/emph on the sink */
589 	drm_dp_dpcd_write(dp_info->aux, DP_TRAINING_LANE0_SET,
590 			  dp_info->train_set, dp_info->dp_lane_count);
591 }
592 
593 static void radeon_dp_set_tp(struct radeon_dp_link_train_info *dp_info, int tp)
594 {
595 	int rtp = 0;
596 
597 	/* set training pattern on the source */
598 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder) {
599 		switch (tp) {
600 		case DP_TRAINING_PATTERN_1:
601 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN1;
602 			break;
603 		case DP_TRAINING_PATTERN_2:
604 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN2;
605 			break;
606 		case DP_TRAINING_PATTERN_3:
607 			rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN3;
608 			break;
609 		}
610 		atombios_dig_encoder_setup(dp_info->encoder, rtp, 0);
611 	} else {
612 		switch (tp) {
613 		case DP_TRAINING_PATTERN_1:
614 			rtp = 0;
615 			break;
616 		case DP_TRAINING_PATTERN_2:
617 			rtp = 1;
618 			break;
619 		}
620 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_PATTERN_SEL,
621 					  dp_info->dp_clock, dp_info->enc_id, rtp);
622 	}
623 
624 	/* enable training pattern on the sink */
625 	drm_dp_dpcd_writeb(dp_info->aux, DP_TRAINING_PATTERN_SET, tp);
626 }
627 
628 static int radeon_dp_link_train_init(struct radeon_dp_link_train_info *dp_info)
629 {
630 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(dp_info->encoder);
631 	struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
632 	u8 tmp;
633 
634 	/* power up the sink */
635 	radeon_dp_set_rx_power_state(dp_info->connector, DP_SET_POWER_D0);
636 
637 	/* possibly enable downspread on the sink */
638 	if (dp_info->dpcd[3] & 0x1)
639 		drm_dp_dpcd_writeb(dp_info->aux,
640 				   DP_DOWNSPREAD_CTRL, DP_SPREAD_AMP_0_5);
641 	else
642 		drm_dp_dpcd_writeb(dp_info->aux,
643 				   DP_DOWNSPREAD_CTRL, 0);
644 
645 	if (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)
646 		drm_dp_dpcd_writeb(dp_info->aux, DP_EDP_CONFIGURATION_SET, 1);
647 
648 	/* set the lane count on the sink */
649 	tmp = dp_info->dp_lane_count;
650 	if (drm_dp_enhanced_frame_cap(dp_info->dpcd))
651 		tmp |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
652 	drm_dp_dpcd_writeb(dp_info->aux, DP_LANE_COUNT_SET, tmp);
653 
654 	/* set the link rate on the sink */
655 	tmp = drm_dp_link_rate_to_bw_code(dp_info->dp_clock);
656 	drm_dp_dpcd_writeb(dp_info->aux, DP_LINK_BW_SET, tmp);
657 
658 	/* start training on the source */
659 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
660 		atombios_dig_encoder_setup(dp_info->encoder,
661 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_START, 0);
662 	else
663 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_START,
664 					  dp_info->dp_clock, dp_info->enc_id, 0);
665 
666 	/* disable the training pattern on the sink */
667 	drm_dp_dpcd_writeb(dp_info->aux,
668 			   DP_TRAINING_PATTERN_SET,
669 			   DP_TRAINING_PATTERN_DISABLE);
670 
671 	return 0;
672 }
673 
674 static int radeon_dp_link_train_finish(struct radeon_dp_link_train_info *dp_info)
675 {
676 	udelay(400);
677 
678 	/* disable the training pattern on the sink */
679 	drm_dp_dpcd_writeb(dp_info->aux,
680 			   DP_TRAINING_PATTERN_SET,
681 			   DP_TRAINING_PATTERN_DISABLE);
682 
683 	/* disable the training pattern on the source */
684 	if (ASIC_IS_DCE4(dp_info->rdev) || !dp_info->use_dpencoder)
685 		atombios_dig_encoder_setup(dp_info->encoder,
686 					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_COMPLETE, 0);
687 	else
688 		radeon_dp_encoder_service(dp_info->rdev, ATOM_DP_ACTION_TRAINING_COMPLETE,
689 					  dp_info->dp_clock, dp_info->enc_id, 0);
690 
691 	return 0;
692 }
693 
694 static int radeon_dp_link_train_cr(struct radeon_dp_link_train_info *dp_info)
695 {
696 	bool clock_recovery;
697  	u8 voltage;
698 	int i;
699 
700 	radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_1);
701 	memset(dp_info->train_set, 0, 4);
702 	radeon_dp_update_vs_emph(dp_info);
703 
704 	udelay(400);
705 
706 	/* clock recovery loop */
707 	clock_recovery = false;
708 	dp_info->tries = 0;
709 	voltage = 0xff;
710 	while (1) {
711 		drm_dp_link_train_clock_recovery_delay(dp_info->dpcd);
712 
713 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
714 						 dp_info->link_status) <= 0) {
715 			DRM_ERROR("displayport link status failed\n");
716 			break;
717 		}
718 
719 		if (drm_dp_clock_recovery_ok(dp_info->link_status, dp_info->dp_lane_count)) {
720 			clock_recovery = true;
721 			break;
722 		}
723 
724 		for (i = 0; i < dp_info->dp_lane_count; i++) {
725 			if ((dp_info->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
726 				break;
727 		}
728 		if (i == dp_info->dp_lane_count) {
729 			DRM_ERROR("clock recovery reached max voltage\n");
730 			break;
731 		}
732 
733 		if ((dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
734 			++dp_info->tries;
735 			if (dp_info->tries == 5) {
736 				DRM_ERROR("clock recovery tried 5 times\n");
737 				break;
738 			}
739 		} else
740 			dp_info->tries = 0;
741 
742 		voltage = dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
743 
744 		/* Compute new train_set as requested by sink */
745 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
746 
747 		radeon_dp_update_vs_emph(dp_info);
748 	}
749 	if (!clock_recovery) {
750 		DRM_ERROR("clock recovery failed\n");
751 		return -1;
752 	} else {
753 		DRM_DEBUG_KMS("clock recovery at voltage %d pre-emphasis %d\n",
754 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
755 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK) >>
756 			  DP_TRAIN_PRE_EMPHASIS_SHIFT);
757 		return 0;
758 	}
759 }
760 
761 static int radeon_dp_link_train_ce(struct radeon_dp_link_train_info *dp_info)
762 {
763 	bool channel_eq;
764 
765 	if (dp_info->tp3_supported)
766 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_3);
767 	else
768 		radeon_dp_set_tp(dp_info, DP_TRAINING_PATTERN_2);
769 
770 	/* channel equalization loop */
771 	dp_info->tries = 0;
772 	channel_eq = false;
773 	while (1) {
774 		drm_dp_link_train_channel_eq_delay(dp_info->dpcd);
775 
776 		if (drm_dp_dpcd_read_link_status(dp_info->aux,
777 						 dp_info->link_status) <= 0) {
778 			DRM_ERROR("displayport link status failed\n");
779 			break;
780 		}
781 
782 		if (drm_dp_channel_eq_ok(dp_info->link_status, dp_info->dp_lane_count)) {
783 			channel_eq = true;
784 			break;
785 		}
786 
787 		/* Try 5 times */
788 		if (dp_info->tries > 5) {
789 			DRM_ERROR("channel eq failed: 5 tries\n");
790 			break;
791 		}
792 
793 		/* Compute new train_set as requested by sink */
794 		dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count, dp_info->train_set);
795 
796 		radeon_dp_update_vs_emph(dp_info);
797 		dp_info->tries++;
798 	}
799 
800 	if (!channel_eq) {
801 		DRM_ERROR("channel eq failed\n");
802 		return -1;
803 	} else {
804 		DRM_DEBUG_KMS("channel eq at voltage %d pre-emphasis %d\n",
805 			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
806 			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK)
807 			  >> DP_TRAIN_PRE_EMPHASIS_SHIFT);
808 		return 0;
809 	}
810 }
811 
812 void radeon_dp_link_train(struct drm_encoder *encoder,
813 			  struct drm_connector *connector)
814 {
815 	struct drm_device *dev = encoder->dev;
816 	struct radeon_device *rdev = dev->dev_private;
817 	struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
818 	struct radeon_encoder_atom_dig *dig;
819 	struct radeon_connector *radeon_connector;
820 	struct radeon_connector_atom_dig *dig_connector;
821 	struct radeon_dp_link_train_info dp_info;
822 	int index;
823 	u8 tmp, frev, crev;
824 
825 	if (!radeon_encoder->enc_priv)
826 		return;
827 	dig = radeon_encoder->enc_priv;
828 
829 	radeon_connector = to_radeon_connector(connector);
830 	if (!radeon_connector->con_priv)
831 		return;
832 	dig_connector = radeon_connector->con_priv;
833 
834 	if ((dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_DISPLAYPORT) &&
835 	    (dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_eDP))
836 		return;
837 
838 	/* DPEncoderService newer than 1.1 can't program properly the
839 	 * training pattern. When facing such version use the
840 	 * DIGXEncoderControl (X== 1 | 2)
841 	 */
842 	dp_info.use_dpencoder = true;
843 	index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
844 	if (atom_parse_cmd_header(rdev->mode_info.atom_context, index, &frev, &crev)) {
845 		if (crev > 1) {
846 			dp_info.use_dpencoder = false;
847 		}
848 	}
849 
850 	dp_info.enc_id = 0;
851 	if (dig->dig_encoder)
852 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG2_ENCODER;
853 	else
854 		dp_info.enc_id |= ATOM_DP_CONFIG_DIG1_ENCODER;
855 	if (dig->linkb)
856 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_B;
857 	else
858 		dp_info.enc_id |= ATOM_DP_CONFIG_LINK_A;
859 
860 	if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux, DP_MAX_LANE_COUNT, &tmp)
861 	    == 1) {
862 		if (ASIC_IS_DCE5(rdev) && (tmp & DP_TPS3_SUPPORTED))
863 			dp_info.tp3_supported = true;
864 		else
865 			dp_info.tp3_supported = false;
866 	} else {
867 		dp_info.tp3_supported = false;
868 	}
869 
870 	memcpy(dp_info.dpcd, dig_connector->dpcd, DP_RECEIVER_CAP_SIZE);
871 	dp_info.rdev = rdev;
872 	dp_info.encoder = encoder;
873 	dp_info.connector = connector;
874 	dp_info.dp_lane_count = dig_connector->dp_lane_count;
875 	dp_info.dp_clock = dig_connector->dp_clock;
876 	dp_info.aux = &radeon_connector->ddc_bus->aux;
877 
878 	if (radeon_dp_link_train_init(&dp_info))
879 		goto done;
880 	if (radeon_dp_link_train_cr(&dp_info))
881 		goto done;
882 	if (radeon_dp_link_train_ce(&dp_info))
883 		goto done;
884 done:
885 	if (radeon_dp_link_train_finish(&dp_info))
886 		return;
887 }
888