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v3.1
  1/*
  2 * Copyright 2009 Red Hat Inc.
  3 *
  4 * Permission is hereby granted, free of charge, to any person obtaining a
  5 * copy of this software and associated documentation files (the "Software"),
  6 * to deal in the Software without restriction, including without limitation
  7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  8 * and/or sell copies of the Software, and to permit persons to whom the
  9 * Software is furnished to do so, subject to the following conditions:
 10 *
 11 * The above copyright notice and this permission notice shall be included in
 12 * all copies or substantial portions of the Software.
 13 *
 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 20 * OTHER DEALINGS IN THE SOFTWARE.
 21 *
 22 * Authors: Ben Skeggs
 23 */
 24
 25#include "drmP.h"
 26
 27#include "nouveau_drv.h"
 28#include "nouveau_i2c.h"
 29#include "nouveau_connector.h"
 30#include "nouveau_encoder.h"
 
 31
 32static int
 33auxch_rd(struct drm_encoder *encoder, int address, uint8_t *buf, int size)
 34{
 35	struct drm_device *dev = encoder->dev;
 36	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 37	struct nouveau_i2c_chan *auxch;
 38	int ret;
 39
 40	auxch = nouveau_i2c_find(dev, nv_encoder->dcb->i2c_index);
 41	if (!auxch)
 42		return -ENODEV;
 43
 44	ret = nouveau_dp_auxch(auxch, 9, address, buf, size);
 45	if (ret)
 46		return ret;
 47
 48	return 0;
 49}
 50
 51static int
 52auxch_wr(struct drm_encoder *encoder, int address, uint8_t *buf, int size)
 53{
 54	struct drm_device *dev = encoder->dev;
 55	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 56	struct nouveau_i2c_chan *auxch;
 57	int ret;
 58
 59	auxch = nouveau_i2c_find(dev, nv_encoder->dcb->i2c_index);
 60	if (!auxch)
 61		return -ENODEV;
 
 
 62
 63	ret = nouveau_dp_auxch(auxch, 8, address, buf, size);
 64	return ret;
 65}
 66
 67static int
 68nouveau_dp_lane_count_set(struct drm_encoder *encoder, uint8_t cmd)
 69{
 70	struct drm_device *dev = encoder->dev;
 71	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 72	uint32_t tmp;
 73	int or = nv_encoder->or, link = !(nv_encoder->dcb->sorconf.link & 1);
 74
 75	tmp  = nv_rd32(dev, NV50_SOR_DP_CTRL(or, link));
 76	tmp &= ~(NV50_SOR_DP_CTRL_ENHANCED_FRAME_ENABLED |
 77		 NV50_SOR_DP_CTRL_LANE_MASK);
 78	tmp |= ((1 << (cmd & DP_LANE_COUNT_MASK)) - 1) << 16;
 79	if (cmd & DP_LANE_COUNT_ENHANCED_FRAME_EN)
 80		tmp |= NV50_SOR_DP_CTRL_ENHANCED_FRAME_ENABLED;
 81	nv_wr32(dev, NV50_SOR_DP_CTRL(or, link), tmp);
 82
 83	return auxch_wr(encoder, DP_LANE_COUNT_SET, &cmd, 1);
 84}
 85
 86static int
 87nouveau_dp_link_bw_set(struct drm_encoder *encoder, uint8_t cmd)
 88{
 89	struct drm_device *dev = encoder->dev;
 90	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 91	uint32_t tmp;
 92	int reg = 0x614300 + (nv_encoder->or * 0x800);
 93
 94	tmp  = nv_rd32(dev, reg);
 95	tmp &= 0xfff3ffff;
 96	if (cmd == DP_LINK_BW_2_7)
 97		tmp |= 0x00040000;
 98	nv_wr32(dev, reg, tmp);
 99
100	return auxch_wr(encoder, DP_LINK_BW_SET, &cmd, 1);
101}
102
103static int
104nouveau_dp_link_train_set(struct drm_encoder *encoder, int pattern)
105{
106	struct drm_device *dev = encoder->dev;
107	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
108	uint32_t tmp;
109	uint8_t cmd;
110	int or = nv_encoder->or, link = !(nv_encoder->dcb->sorconf.link & 1);
111	int ret;
 
112
113	tmp  = nv_rd32(dev, NV50_SOR_DP_CTRL(or, link));
114	tmp &= ~NV50_SOR_DP_CTRL_TRAINING_PATTERN;
115	tmp |= (pattern << 24);
116	nv_wr32(dev, NV50_SOR_DP_CTRL(or, link), tmp);
117
118	ret = auxch_rd(encoder, DP_TRAINING_PATTERN_SET, &cmd, 1);
119	if (ret)
120		return ret;
121	cmd &= ~DP_TRAINING_PATTERN_MASK;
122	cmd |= (pattern & DP_TRAINING_PATTERN_MASK);
123	return auxch_wr(encoder, DP_TRAINING_PATTERN_SET, &cmd, 1);
124}
125
126static int
127nouveau_dp_max_voltage_swing(struct drm_encoder *encoder)
128{
129	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
130	struct drm_device *dev = encoder->dev;
131	struct bit_displayport_encoder_table_entry *dpse;
132	struct bit_displayport_encoder_table *dpe;
133	int i, dpe_headerlen, max_vs = 0;
134
135	dpe = nouveau_bios_dp_table(dev, nv_encoder->dcb, &dpe_headerlen);
136	if (!dpe)
137		return false;
138	dpse = (void *)((char *)dpe + dpe_headerlen);
139
140	for (i = 0; i < dpe_headerlen; i++, dpse++) {
141		if (dpse->vs_level > max_vs)
142			max_vs = dpse->vs_level;
143	}
144
145	return max_vs;
146}
 
147
148static int
149nouveau_dp_max_pre_emphasis(struct drm_encoder *encoder, int vs)
150{
151	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
152	struct drm_device *dev = encoder->dev;
153	struct bit_displayport_encoder_table_entry *dpse;
154	struct bit_displayport_encoder_table *dpe;
155	int i, dpe_headerlen, max_pre = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
156
157	dpe = nouveau_bios_dp_table(dev, nv_encoder->dcb, &dpe_headerlen);
158	if (!dpe)
159		return false;
160	dpse = (void *)((char *)dpe + dpe_headerlen);
161
162	for (i = 0; i < dpe_headerlen; i++, dpse++) {
163		if (dpse->vs_level != vs)
164			continue;
165
166		if (dpse->pre_level > max_pre)
167			max_pre = dpse->pre_level;
168	}
169
170	return max_pre;
171}
172
173static bool
174nouveau_dp_link_train_adjust(struct drm_encoder *encoder, uint8_t *config)
175{
176	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
177	struct drm_device *dev = encoder->dev;
178	struct bit_displayport_encoder_table *dpe;
179	int ret, i, dpe_headerlen, vs = 0, pre = 0;
180	uint8_t request[2];
181
182	dpe = nouveau_bios_dp_table(dev, nv_encoder->dcb, &dpe_headerlen);
183	if (!dpe)
184		return false;
185
186	ret = auxch_rd(encoder, DP_ADJUST_REQUEST_LANE0_1, request, 2);
187	if (ret)
188		return false;
189
190	NV_DEBUG_KMS(dev, "\t\tadjust 0x%02x 0x%02x\n", request[0], request[1]);
191
192	/* Keep all lanes at the same level.. */
193	for (i = 0; i < nv_encoder->dp.link_nr; i++) {
194		int lane_req = (request[i >> 1] >> ((i & 1) << 2)) & 0xf;
195		int lane_vs = lane_req & 3;
196		int lane_pre = (lane_req >> 2) & 3;
197
198		if (lane_vs > vs)
199			vs = lane_vs;
200		if (lane_pre > pre)
201			pre = lane_pre;
202	}
203
204	if (vs >= nouveau_dp_max_voltage_swing(encoder)) {
205		vs  = nouveau_dp_max_voltage_swing(encoder);
206		vs |= 4;
207	}
208
209	if (pre >= nouveau_dp_max_pre_emphasis(encoder, vs & 3)) {
210		pre  = nouveau_dp_max_pre_emphasis(encoder, vs & 3);
211		pre |= 4;
 
212	}
213
214	/* Update the configuration for all lanes.. */
215	for (i = 0; i < nv_encoder->dp.link_nr; i++)
216		config[i] = (pre << 3) | vs;
217
218	return true;
219}
220
221static bool
222nouveau_dp_link_train_commit(struct drm_encoder *encoder, uint8_t *config)
223{
224	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
225	struct drm_device *dev = encoder->dev;
226	struct bit_displayport_encoder_table_entry *dpse;
227	struct bit_displayport_encoder_table *dpe;
228	int or = nv_encoder->or, link = !(nv_encoder->dcb->sorconf.link & 1);
229	int dpe_headerlen, ret, i;
230
231	NV_DEBUG_KMS(dev, "\t\tconfig 0x%02x 0x%02x 0x%02x 0x%02x\n",
232		 config[0], config[1], config[2], config[3]);
233
234	dpe = nouveau_bios_dp_table(dev, nv_encoder->dcb, &dpe_headerlen);
235	if (!dpe)
236		return false;
237	dpse = (void *)((char *)dpe + dpe_headerlen);
238
239	for (i = 0; i < dpe->record_nr; i++, dpse++) {
240		if (dpse->vs_level == (config[0] & 3) &&
241		    dpse->pre_level == ((config[0] >> 3) & 3))
242			break;
243	}
244	BUG_ON(i == dpe->record_nr);
245
246	for (i = 0; i < nv_encoder->dp.link_nr; i++) {
247		const int shift[4] = { 16, 8, 0, 24 };
248		uint32_t mask = 0xff << shift[i];
249		uint32_t reg0, reg1, reg2;
250
251		reg0  = nv_rd32(dev, NV50_SOR_DP_UNK118(or, link)) & ~mask;
252		reg0 |= (dpse->reg0 << shift[i]);
253		reg1  = nv_rd32(dev, NV50_SOR_DP_UNK120(or, link)) & ~mask;
254		reg1 |= (dpse->reg1 << shift[i]);
255		reg2  = nv_rd32(dev, NV50_SOR_DP_UNK130(or, link)) & 0xffff00ff;
256		reg2 |= (dpse->reg2 << 8);
257		nv_wr32(dev, NV50_SOR_DP_UNK118(or, link), reg0);
258		nv_wr32(dev, NV50_SOR_DP_UNK120(or, link), reg1);
259		nv_wr32(dev, NV50_SOR_DP_UNK130(or, link), reg2);
260	}
261
262	ret = auxch_wr(encoder, DP_TRAINING_LANE0_SET, config, 4);
263	if (ret)
264		return false;
 
265
266	return true;
 
 
 
 
 
 
267}
268
269bool
270nouveau_dp_link_train(struct drm_encoder *encoder)
 
271{
272	struct drm_device *dev = encoder->dev;
273	struct drm_nouveau_private *dev_priv = dev->dev_private;
274	struct nouveau_gpio_engine *pgpio = &dev_priv->engine.gpio;
275	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
276	struct nouveau_connector *nv_connector;
277	struct bit_displayport_encoder_table *dpe;
278	int dpe_headerlen;
279	uint8_t config[4], status[3];
280	bool cr_done, cr_max_vs, eq_done, hpd_state;
281	int ret = 0, i, tries, voltage;
282
283	NV_DEBUG_KMS(dev, "link training!!\n");
284
285	nv_connector = nouveau_encoder_connector_get(nv_encoder);
286	if (!nv_connector)
287		return false;
288
289	dpe = nouveau_bios_dp_table(dev, nv_encoder->dcb, &dpe_headerlen);
290	if (!dpe) {
291		NV_ERROR(dev, "SOR-%d: no DP encoder table!\n", nv_encoder->or);
292		return false;
293	}
294
295	/* disable hotplug detect, this flips around on some panels during
296	 * link training.
297	 */
298	hpd_state = pgpio->irq_enable(dev, nv_connector->dcb->gpio_tag, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
299
300	if (dpe->script0) {
301		NV_DEBUG_KMS(dev, "SOR-%d: running DP script 0\n", nv_encoder->or);
302		nouveau_bios_run_init_table(dev, le16_to_cpu(dpe->script0),
303					    nv_encoder->dcb);
304	}
305
306train:
307	cr_done = eq_done = false;
308
309	/* set link configuration */
310	NV_DEBUG_KMS(dev, "\tbegin train: bw %d, lanes %d\n",
311		 nv_encoder->dp.link_bw, nv_encoder->dp.link_nr);
312
313	ret = nouveau_dp_link_bw_set(encoder, nv_encoder->dp.link_bw);
314	if (ret)
315		return false;
316
317	config[0] = nv_encoder->dp.link_nr;
318	if (nv_encoder->dp.dpcd_version >= 0x11 &&
319	    nv_encoder->dp.enhanced_frame)
320		config[0] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
 
321
322	ret = nouveau_dp_lane_count_set(encoder, config[0]);
323	if (ret)
324		return false;
 
 
325
326	/* clock recovery */
327	NV_DEBUG_KMS(dev, "\tbegin cr\n");
328	ret = nouveau_dp_link_train_set(encoder, DP_TRAINING_PATTERN_1);
329	if (ret)
330		goto stop;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
331
332	tries = 0;
333	voltage = -1;
334	memset(config, 0x00, sizeof(config));
335	for (;;) {
336		if (!nouveau_dp_link_train_commit(encoder, config))
337			break;
338
339		udelay(100);
 
 
 
 
 
340
341		ret = auxch_rd(encoder, DP_LANE0_1_STATUS, status, 2);
342		if (ret)
343			break;
344		NV_DEBUG_KMS(dev, "\t\tstatus: 0x%02x 0x%02x\n",
345			 status[0], status[1]);
346
347		cr_done = true;
348		cr_max_vs = false;
349		for (i = 0; i < nv_encoder->dp.link_nr; i++) {
350			int lane = (status[i >> 1] >> ((i & 1) * 4)) & 0xf;
351
352			if (!(lane & DP_LANE_CR_DONE)) {
353				cr_done = false;
354				if (config[i] & DP_TRAIN_MAX_PRE_EMPHASIS_REACHED)
355					cr_max_vs = true;
356				break;
357			}
358		}
359
360		if ((config[0] & DP_TRAIN_VOLTAGE_SWING_MASK) != voltage) {
361			voltage = config[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
362			tries = 0;
363		}
 
 
364
365		if (cr_done || cr_max_vs || (++tries == 5))
366			break;
367
368		if (!nouveau_dp_link_train_adjust(encoder, config))
369			break;
 
 
 
370	}
371
372	if (!cr_done)
373		goto stop;
 
374
375	/* channel equalisation */
376	NV_DEBUG_KMS(dev, "\tbegin eq\n");
377	ret = nouveau_dp_link_train_set(encoder, DP_TRAINING_PATTERN_2);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
378	if (ret)
379		goto stop;
380
381	for (tries = 0; tries <= 5; tries++) {
382		udelay(400);
 
 
383
384		ret = auxch_rd(encoder, DP_LANE0_1_STATUS, status, 3);
385		if (ret)
386			break;
387		NV_DEBUG_KMS(dev, "\t\tstatus: 0x%02x 0x%02x\n",
388			 status[0], status[1]);
389
390		eq_done = true;
391		if (!(status[2] & DP_INTERLANE_ALIGN_DONE))
392			eq_done = false;
393
394		for (i = 0; eq_done && i < nv_encoder->dp.link_nr; i++) {
395			int lane = (status[i >> 1] >> ((i & 1) * 4)) & 0xf;
396
397			if (!(lane & DP_LANE_CR_DONE)) {
398				cr_done = false;
399				break;
400			}
401
402			if (!(lane & DP_LANE_CHANNEL_EQ_DONE) ||
403			    !(lane & DP_LANE_SYMBOL_LOCKED)) {
404				eq_done = false;
405				break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
406			}
407		}
408
409		if (eq_done || !cr_done)
410			break;
411
412		if (!nouveau_dp_link_train_adjust(encoder, config) ||
413		    !nouveau_dp_link_train_commit(encoder, config))
414			break;
415	}
416
417stop:
418	/* end link training */
419	ret = nouveau_dp_link_train_set(encoder, DP_TRAINING_PATTERN_DISABLE);
420	if (ret)
421		return false;
422
423	/* retry at a lower setting, if possible */
424	if (!ret && !(eq_done && cr_done)) {
425		NV_DEBUG_KMS(dev, "\twe failed\n");
426		if (nv_encoder->dp.link_bw != DP_LINK_BW_1_62) {
427			NV_DEBUG_KMS(dev, "retry link training at low rate\n");
428			nv_encoder->dp.link_bw = DP_LINK_BW_1_62;
429			goto train;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
430		}
431	}
432
433	if (dpe->script1) {
434		NV_DEBUG_KMS(dev, "SOR-%d: running DP script 1\n", nv_encoder->or);
435		nouveau_bios_run_init_table(dev, le16_to_cpu(dpe->script1),
436					    nv_encoder->dcb);
 
 
 
 
 
 
437	}
438
439	/* re-enable hotplug detect */
440	pgpio->irq_enable(dev, nv_connector->dcb->gpio_tag, hpd_state);
441
442	return eq_done;
443}
444
445bool
446nouveau_dp_detect(struct drm_encoder *encoder)
447{
448	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
449	struct drm_device *dev = encoder->dev;
450	uint8_t dpcd[4];
451	int ret;
452
453	ret = auxch_rd(encoder, 0x0000, dpcd, 4);
454	if (ret)
455		return false;
456
457	NV_DEBUG_KMS(dev, "encoder: link_bw %d, link_nr %d\n"
458		      "display: link_bw %d, link_nr %d version 0x%02x\n",
459		 nv_encoder->dcb->dpconf.link_bw,
460		 nv_encoder->dcb->dpconf.link_nr,
461		 dpcd[1], dpcd[2] & 0x0f, dpcd[0]);
462
463	nv_encoder->dp.dpcd_version = dpcd[0];
464
465	nv_encoder->dp.link_bw = dpcd[1];
466	if (nv_encoder->dp.link_bw != DP_LINK_BW_1_62 &&
467	    !nv_encoder->dcb->dpconf.link_bw)
468		nv_encoder->dp.link_bw = DP_LINK_BW_1_62;
469
470	nv_encoder->dp.link_nr = dpcd[2] & DP_MAX_LANE_COUNT_MASK;
471	if (nv_encoder->dp.link_nr > nv_encoder->dcb->dpconf.link_nr)
472		nv_encoder->dp.link_nr = nv_encoder->dcb->dpconf.link_nr;
473
474	nv_encoder->dp.enhanced_frame = (dpcd[2] & DP_ENHANCED_FRAME_CAP);
 
475
476	return true;
477}
478
479int
480nouveau_dp_auxch(struct nouveau_i2c_chan *auxch, int cmd, int addr,
481		 uint8_t *data, int data_nr)
482{
483	struct drm_device *dev = auxch->dev;
484	uint32_t tmp, ctrl, stat = 0, data32[4] = {};
485	int ret = 0, i, index = auxch->rd;
486
487	NV_DEBUG_KMS(dev, "ch %d cmd %d addr 0x%x len %d\n", index, cmd, addr, data_nr);
488
489	tmp = nv_rd32(dev, NV50_AUXCH_CTRL(auxch->rd));
490	nv_wr32(dev, NV50_AUXCH_CTRL(auxch->rd), tmp | 0x00100000);
491	tmp = nv_rd32(dev, NV50_AUXCH_CTRL(auxch->rd));
492	if (!(tmp & 0x01000000)) {
493		NV_ERROR(dev, "expected bit 24 == 1, got 0x%08x\n", tmp);
494		ret = -EIO;
495		goto out;
496	}
497
498	for (i = 0; i < 3; i++) {
499		tmp = nv_rd32(dev, NV50_AUXCH_STAT(auxch->rd));
500		if (tmp & NV50_AUXCH_STAT_STATE_READY)
501			break;
502		udelay(100);
503	}
504
505	if (i == 3) {
506		ret = -EBUSY;
507		goto out;
508	}
509
510	if (!(cmd & 1)) {
511		memcpy(data32, data, data_nr);
512		for (i = 0; i < 4; i++) {
513			NV_DEBUG_KMS(dev, "wr %d: 0x%08x\n", i, data32[i]);
514			nv_wr32(dev, NV50_AUXCH_DATA_OUT(index, i), data32[i]);
515		}
516	}
 
 
 
 
517
518	nv_wr32(dev, NV50_AUXCH_ADDR(index), addr);
519	ctrl  = nv_rd32(dev, NV50_AUXCH_CTRL(index));
520	ctrl &= ~(NV50_AUXCH_CTRL_CMD | NV50_AUXCH_CTRL_LEN);
521	ctrl |= (cmd << NV50_AUXCH_CTRL_CMD_SHIFT);
522	ctrl |= ((data_nr - 1) << NV50_AUXCH_CTRL_LEN_SHIFT);
523
524	for (i = 0; i < 16; i++) {
525		nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl | 0x80000000);
526		nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl);
527		nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl | 0x00010000);
528		if (!nv_wait(dev, NV50_AUXCH_CTRL(index),
529			     0x00010000, 0x00000000)) {
530			NV_ERROR(dev, "expected bit 16 == 0, got 0x%08x\n",
531				 nv_rd32(dev, NV50_AUXCH_CTRL(index)));
532			ret = -EBUSY;
533			goto out;
534		}
535
536		udelay(400);
 
537
538		stat = nv_rd32(dev, NV50_AUXCH_STAT(index));
539		if ((stat & NV50_AUXCH_STAT_REPLY_AUX) !=
540			    NV50_AUXCH_STAT_REPLY_AUX_DEFER)
541			break;
542	}
543
544	if (i == 16) {
545		NV_ERROR(dev, "auxch DEFER too many times, bailing\n");
546		ret = -EREMOTEIO;
547		goto out;
548	}
549
550	if (cmd & 1) {
551		if ((stat & NV50_AUXCH_STAT_COUNT) != data_nr) {
552			ret = -EREMOTEIO;
553			goto out;
 
 
554		}
555
556		for (i = 0; i < 4; i++) {
557			data32[i] = nv_rd32(dev, NV50_AUXCH_DATA_IN(index, i));
558			NV_DEBUG_KMS(dev, "rd %d: 0x%08x\n", i, data32[i]);
559		}
560		memcpy(data, data32, data_nr);
561	}
562
563out:
564	tmp = nv_rd32(dev, NV50_AUXCH_CTRL(auxch->rd));
565	nv_wr32(dev, NV50_AUXCH_CTRL(auxch->rd), tmp & ~0x00100000);
566	tmp = nv_rd32(dev, NV50_AUXCH_CTRL(auxch->rd));
567	if (tmp & 0x01000000) {
568		NV_ERROR(dev, "expected bit 24 == 0, got 0x%08x\n", tmp);
569		ret = -EIO;
570	}
571
572	udelay(400);
573
574	return ret ? ret : (stat & NV50_AUXCH_STAT_REPLY);
575}
576
577static int
578nouveau_dp_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
579{
580	struct nouveau_i2c_chan *auxch = (struct nouveau_i2c_chan *)adap;
581	struct drm_device *dev = auxch->dev;
582	struct i2c_msg *msg = msgs;
583	int ret, mcnt = num;
584
585	while (mcnt--) {
586		u8 remaining = msg->len;
587		u8 *ptr = msg->buf;
588
589		while (remaining) {
590			u8 cnt = (remaining > 16) ? 16 : remaining;
591			u8 cmd;
 
592
593			if (msg->flags & I2C_M_RD)
594				cmd = AUX_I2C_READ;
595			else
596				cmd = AUX_I2C_WRITE;
597
598			if (mcnt || remaining > 16)
599				cmd |= AUX_I2C_MOT;
600
601			ret = nouveau_dp_auxch(auxch, cmd, msg->addr, ptr, cnt);
602			if (ret < 0)
603				return ret;
 
604
605			switch (ret & NV50_AUXCH_STAT_REPLY_I2C) {
606			case NV50_AUXCH_STAT_REPLY_I2C_ACK:
607				break;
608			case NV50_AUXCH_STAT_REPLY_I2C_NACK:
609				return -EREMOTEIO;
610			case NV50_AUXCH_STAT_REPLY_I2C_DEFER:
611				udelay(100);
612				continue;
613			default:
614				NV_ERROR(dev, "bad auxch reply: 0x%08x\n", ret);
615				return -EREMOTEIO;
616			}
617
618			ptr += cnt;
619			remaining -= cnt;
620		}
621
622		msg++;
623	}
624
625	return num;
626}
627
628static u32
629nouveau_dp_i2c_func(struct i2c_adapter *adap)
630{
631	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
632}
633
634const struct i2c_algorithm nouveau_dp_i2c_algo = {
635	.master_xfer = nouveau_dp_i2c_xfer,
636	.functionality = nouveau_dp_i2c_func
637};
v6.9.4
  1/*
  2 * Copyright 2009 Red Hat Inc.
  3 *
  4 * Permission is hereby granted, free of charge, to any person obtaining a
  5 * copy of this software and associated documentation files (the "Software"),
  6 * to deal in the Software without restriction, including without limitation
  7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  8 * and/or sell copies of the Software, and to permit persons to whom the
  9 * Software is furnished to do so, subject to the following conditions:
 10 *
 11 * The above copyright notice and this permission notice shall be included in
 12 * all copies or substantial portions of the Software.
 13 *
 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 20 * OTHER DEALINGS IN THE SOFTWARE.
 21 *
 22 * Authors: Ben Skeggs
 23 */
 24
 25#include <drm/display/drm_dp_helper.h>
 26
 27#include "nouveau_drv.h"
 
 28#include "nouveau_connector.h"
 29#include "nouveau_encoder.h"
 30#include "nouveau_crtc.h"
 31
 32#include <nvif/if0011.h>
 
 
 
 
 
 
 33
 34MODULE_PARM_DESC(mst, "Enable DisplayPort multi-stream (default: enabled)");
 35static int nouveau_mst = 1;
 36module_param_named(mst, nouveau_mst, int, 0400);
 37
 38static bool
 39nouveau_dp_has_sink_count(struct drm_connector *connector,
 40			  struct nouveau_encoder *outp)
 41{
 42	return drm_dp_read_sink_count_cap(connector, outp->dp.dpcd, &outp->dp.desc);
 43}
 44
 45static bool
 46nouveau_dp_probe_lttpr(struct nouveau_encoder *outp)
 47{
 48	u8 rev, size = sizeof(rev);
 
 
 49	int ret;
 50
 51	ret = nvif_outp_dp_aux_xfer(&outp->outp, DP_AUX_NATIVE_READ, &size,
 52				    DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV,
 53				    &rev);
 54	if (ret || size < sizeof(rev) || rev < 0x14)
 55		return false;
 56
 57	return true;
 
 58}
 59
 60static enum drm_connector_status
 61nouveau_dp_probe_dpcd(struct nouveau_connector *nv_connector,
 62		      struct nouveau_encoder *outp)
 63{
 64	struct drm_connector *connector = &nv_connector->base;
 65	struct drm_dp_aux *aux = &nv_connector->aux;
 66	struct nv50_mstm *mstm = NULL;
 67	enum drm_connector_status status = connector_status_disconnected;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 68	int ret;
 69	u8 *dpcd = outp->dp.dpcd;
 70
 71	outp->dp.lttpr.nr = 0;
 72	outp->dp.rate_nr  = 0;
 73	outp->dp.link_nr  = 0;
 74	outp->dp.link_bw  = 0;
 75
 76	if (connector->connector_type != DRM_MODE_CONNECTOR_eDP &&
 77	    nouveau_dp_probe_lttpr(outp) &&
 78	    !drm_dp_read_dpcd_caps(aux, dpcd) &&
 79	    !drm_dp_read_lttpr_common_caps(aux, dpcd, outp->dp.lttpr.caps)) {
 80		int nr = drm_dp_lttpr_count(outp->dp.lttpr.caps);
 81
 82		if (nr) {
 83			drm_dp_dpcd_writeb(aux, DP_PHY_REPEATER_MODE,
 84						DP_PHY_REPEATER_MODE_TRANSPARENT);
 85
 86			if (nr > 0) {
 87				ret = drm_dp_dpcd_writeb(aux, DP_PHY_REPEATER_MODE,
 88							      DP_PHY_REPEATER_MODE_NON_TRANSPARENT);
 89				if (ret != 1) {
 90					drm_dp_dpcd_writeb(aux, DP_PHY_REPEATER_MODE,
 91								DP_PHY_REPEATER_MODE_TRANSPARENT);
 92				} else {
 93					outp->dp.lttpr.nr = nr;
 94				}
 95			}
 96		}
 
 
 
 
 97	}
 98
 99	ret = drm_dp_read_dpcd_caps(aux, dpcd);
100	if (ret < 0)
101		goto out;
102
103	outp->dp.link_nr = dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK;
104	if (outp->dcb->dpconf.link_nr < outp->dp.link_nr)
105		outp->dp.link_nr = outp->dcb->dpconf.link_nr;
106
107	if (outp->dp.lttpr.nr) {
108		int links = drm_dp_lttpr_max_lane_count(outp->dp.lttpr.caps);
109
110		if (links && links < outp->dp.link_nr)
111			outp->dp.link_nr = links;
112	}
113
114	if (connector->connector_type == DRM_MODE_CONNECTOR_eDP && dpcd[DP_DPCD_REV] >= 0x13) {
115		__le16 rates[DP_MAX_SUPPORTED_RATES];
116
117		ret = drm_dp_dpcd_read(aux, DP_SUPPORTED_LINK_RATES, rates, sizeof(rates));
118		if (ret == sizeof(rates)) {
119			for (int i = 0; i < ARRAY_SIZE(rates); i++) {
120				u32 rate = (le16_to_cpu(rates[i]) * 200) / 10;
121				int j;
122
123				if (!rate)
124					break;
125
126				for (j = 0; j < outp->dp.rate_nr; j++) {
127					if (rate > outp->dp.rate[j].rate) {
128						for (int k = outp->dp.rate_nr; k > j; k--)
129							outp->dp.rate[k] = outp->dp.rate[k - 1];
130						break;
131					}
132				}
133
134				outp->dp.rate[j].dpcd = i;
135				outp->dp.rate[j].rate = rate;
136				outp->dp.rate_nr++;
137			}
138		}
139	}
140
141	if (!outp->dp.rate_nr) {
142		const u32 rates[] = { 810000, 540000, 270000, 162000 };
143		u32 max_rate = dpcd[DP_MAX_LINK_RATE] * 27000;
 
144
145		if (outp->dp.lttpr.nr) {
146			int rate = drm_dp_lttpr_max_link_rate(outp->dp.lttpr.caps);
 
147
148			if (rate && rate < max_rate)
149				max_rate = rate;
150		}
151
152		max_rate = min_t(int, max_rate, outp->dcb->dpconf.link_bw);
 
153
154		for (int i = 0; i < ARRAY_SIZE(rates); i++) {
155			if (rates[i] <= max_rate) {
156				outp->dp.rate[outp->dp.rate_nr].dpcd = -1;
157				outp->dp.rate[outp->dp.rate_nr].rate = rates[i];
158				outp->dp.rate_nr++;
159			}
160		}
 
161
162		if (WARN_ON(!outp->dp.rate_nr))
163			goto out;
164	}
165
166	ret = nvif_outp_dp_rates(&outp->outp, outp->dp.rate, outp->dp.rate_nr);
167	if (ret)
168		goto out;
 
 
169
170	for (int i = 0; i < outp->dp.rate_nr; i++) {
171		u32 link_bw = outp->dp.rate[i].rate;
 
 
 
172
173		if (link_bw > outp->dp.link_bw)
174			outp->dp.link_bw = link_bw;
 
 
175	}
176
177	ret = drm_dp_read_desc(aux, &outp->dp.desc, drm_dp_is_branch(dpcd));
178	if (ret < 0)
179		goto out;
 
180
181	if (nouveau_mst) {
182		mstm = outp->dp.mstm;
183		if (mstm)
184			mstm->can_mst = drm_dp_read_mst_cap(aux, dpcd);
185	}
186
187	if (nouveau_dp_has_sink_count(connector, outp)) {
188		ret = drm_dp_read_sink_count(aux);
189		if (ret < 0)
190			goto out;
 
 
 
 
 
 
 
 
 
 
 
 
191
192		outp->dp.sink_count = ret;
 
193
194		/*
195		 * Dongle connected, but no display. Don't bother reading
196		 * downstream port info
197		 */
198		if (!outp->dp.sink_count)
199			return connector_status_disconnected;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
200	}
201
202	ret = drm_dp_read_downstream_info(aux, dpcd,
203					  outp->dp.downstream_ports);
204	if (ret < 0)
205		goto out;
206
207	status = connector_status_connected;
208out:
209	if (status != connector_status_connected) {
210		/* Clear any cached info */
211		outp->dp.sink_count = 0;
212	}
213	return status;
214}
215
216int
217nouveau_dp_detect(struct nouveau_connector *nv_connector,
218		  struct nouveau_encoder *nv_encoder)
219{
220	struct drm_device *dev = nv_encoder->base.base.dev;
221	struct nouveau_drm *drm = nouveau_drm(dev);
222	struct drm_connector *connector = &nv_connector->base;
223	struct nv50_mstm *mstm = nv_encoder->dp.mstm;
224	enum drm_connector_status status;
225	u8 *dpcd = nv_encoder->dp.dpcd;
226	int ret = NOUVEAU_DP_NONE, hpd;
 
 
 
 
 
 
 
 
 
227
228	/* eDP ports don't support hotplugging - so there's no point in probing eDP ports unless we
229	 * haven't probed them once before.
 
 
 
 
 
 
230	 */
231	if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
232		if (connector->status == connector_status_connected)
233			return NOUVEAU_DP_SST;
234		else if (connector->status == connector_status_disconnected)
235			return NOUVEAU_DP_NONE;
236	}
237
238	// Ensure that the aux bus is enabled for probing
239	drm_dp_dpcd_set_powered(&nv_connector->aux, true);
240
241	mutex_lock(&nv_encoder->dp.hpd_irq_lock);
242	if (mstm) {
243		/* If we're not ready to handle MST state changes yet, just
244		 * report the last status of the connector. We'll reprobe it
245		 * once we've resumed.
246		 */
247		if (mstm->suspended) {
248			if (mstm->is_mst)
249				ret = NOUVEAU_DP_MST;
250			else if (connector->status ==
251				 connector_status_connected)
252				ret = NOUVEAU_DP_SST;
253
254			goto out;
255		}
 
 
256	}
257
258	hpd = nvif_outp_detect(&nv_encoder->outp);
259	if (hpd == NOT_PRESENT) {
260		nvif_outp_dp_aux_pwr(&nv_encoder->outp, false);
261		goto out;
262	}
263	nvif_outp_dp_aux_pwr(&nv_encoder->outp, true);
 
 
 
 
264
265	status = nouveau_dp_probe_dpcd(nv_connector, nv_encoder);
266	if (status == connector_status_disconnected) {
267		nvif_outp_dp_aux_pwr(&nv_encoder->outp, false);
268		goto out;
269	}
270
271	/* If we're in MST mode, we're done here */
272	if (mstm && mstm->can_mst && mstm->is_mst) {
273		ret = NOUVEAU_DP_MST;
274		goto out;
275	}
276
277	NV_DEBUG(drm, "sink dpcd version: 0x%02x\n", dpcd[DP_DPCD_REV]);
278	for (int i = 0; i < nv_encoder->dp.rate_nr; i++)
279		NV_DEBUG(drm, "sink rate %d: %d\n", i, nv_encoder->dp.rate[i].rate);
280
281	NV_DEBUG(drm, "encoder: %dx%d\n", nv_encoder->dcb->dpconf.link_nr,
282					  nv_encoder->dcb->dpconf.link_bw);
283	NV_DEBUG(drm, "maximum: %dx%d\n", nv_encoder->dp.link_nr,
284					  nv_encoder->dp.link_bw);
285
286	if (mstm && mstm->can_mst) {
287		ret = nv50_mstm_detect(nv_encoder);
288		if (ret == 1) {
289			ret = NOUVEAU_DP_MST;
290			goto out;
291		} else if (ret != 0) {
292			nvif_outp_dp_aux_pwr(&nv_encoder->outp, false);
293			goto out;
294		}
295	}
296	ret = NOUVEAU_DP_SST;
297
298out:
299	if (mstm && !mstm->suspended && ret != NOUVEAU_DP_MST)
300		nv50_mstm_remove(mstm);
 
 
 
301
302	/* GSP doesn't like when we try to do aux transactions on a port it considers disconnected,
303	 * and since we don't really have a usecase for that anyway - just disable the aux bus here
304	 * if we've decided the connector is disconnected
305	 */
306	if (ret == NOUVEAU_DP_NONE)
307		drm_dp_dpcd_set_powered(&nv_connector->aux, false);
308
309	mutex_unlock(&nv_encoder->dp.hpd_irq_lock);
310	return ret;
311}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
312
313void
314nouveau_dp_power_down(struct nouveau_encoder *outp)
315{
316	struct drm_dp_aux *aux = &outp->conn->aux;
317	int ret;
318	u8 pwr;
319
320	mutex_lock(&outp->dp.hpd_irq_lock);
 
321
322	ret = drm_dp_dpcd_readb(aux, DP_SET_POWER, &pwr);
323	if (ret == 1) {
324		pwr &= ~DP_SET_POWER_MASK;
325		pwr |=  DP_SET_POWER_D3;
326		drm_dp_dpcd_writeb(aux, DP_SET_POWER, pwr);
327	}
328
329	outp->dp.lt.nr = 0;
330	mutex_unlock(&outp->dp.hpd_irq_lock);
331}
332
333static bool
334nouveau_dp_train_link(struct nouveau_encoder *outp, bool retrain)
335{
336	struct drm_dp_aux *aux = &outp->conn->aux;
337	bool post_lt = false;
338	int ret, retries = 0;
339
340	if ( (outp->dp.dpcd[DP_MAX_LANE_COUNT] & 0x20) &&
341	    !(outp->dp.dpcd[DP_MAX_DOWNSPREAD] & DP_TPS4_SUPPORTED))
342	    post_lt = true;
343
344retry:
345	ret = nvif_outp_dp_train(&outp->outp, outp->dp.dpcd,
346					      outp->dp.lttpr.nr,
347					      outp->dp.lt.nr,
348					      outp->dp.lt.bw,
349					      outp->dp.lt.mst,
350					      post_lt,
351					      retrain);
352	if (ret)
353		return false;
354
355	if (post_lt) {
356		u8 stat[DP_LINK_STATUS_SIZE];
357		u8 prev[2];
358		u8 time = 0, adjusts = 0, tmp;
359
360		ret = drm_dp_dpcd_read_phy_link_status(aux, DP_PHY_DPRX, stat);
361		if (ret)
362			return false;
 
 
 
 
 
 
363
364		for (;;) {
365			if (!drm_dp_channel_eq_ok(stat, outp->dp.lt.nr)) {
366				ret = 1;
 
 
367				break;
368			}
369
370			if (!(stat[2] & 0x02))
 
 
371				break;
372
373			msleep(5);
374			time += 5;
375
376			memcpy(prev, &stat[4], sizeof(prev));
377			ret = drm_dp_dpcd_read_phy_link_status(aux, DP_PHY_DPRX, stat);
378			if (ret)
379				break;
380
381			if (!memcmp(prev, &stat[4], sizeof(prev))) {
382				if (time > 200)
383					break;
384			} else {
385				u8 pe[4], vs[4];
386
387				if (adjusts++ == 6)
388					break;
389
390				for (int i = 0; i < outp->dp.lt.nr; i++) {
391					pe[i] = drm_dp_get_adjust_request_pre_emphasis(stat, i) >>
392							DP_TRAIN_PRE_EMPHASIS_SHIFT;
393					vs[i] = drm_dp_get_adjust_request_voltage(stat, i) >>
394							DP_TRAIN_VOLTAGE_SWING_SHIFT;
395				}
396
397				ret = nvif_outp_dp_drive(&outp->outp, outp->dp.lt.nr, pe, vs);
398				if (ret)
399					break;
400
401				time = 0;
402			}
403		}
404
405		if (drm_dp_dpcd_readb(aux, DP_LANE_COUNT_SET, &tmp) == 1) {
406			tmp &= ~0x20;
407			drm_dp_dpcd_writeb(aux, DP_LANE_COUNT_SET, tmp);
408		}
 
 
409	}
410
411	if (ret == 1 && retries++ < 3)
412		goto retry;
413
414	return ret == 0;
415}
416
417bool
418nouveau_dp_train(struct nouveau_encoder *outp, bool mst, u32 khz, u8 bpc)
419{
420	struct nouveau_drm *drm = nouveau_drm(outp->base.base.dev);
421	struct drm_dp_aux *aux = &outp->conn->aux;
422	u32 min_rate;
423	u8 pwr;
424	bool ret = true;
425
426	if (mst)
427		min_rate = outp->dp.link_nr * outp->dp.rate[0].rate;
428	else
429		min_rate = DIV_ROUND_UP(khz * bpc * 3, 8);
430
431	NV_DEBUG(drm, "%s link training (mst:%d min_rate:%d)\n",
432		 outp->base.base.name, mst, min_rate);
433
434	mutex_lock(&outp->dp.hpd_irq_lock);
435
436	if (drm_dp_dpcd_readb(aux, DP_SET_POWER, &pwr) == 1) {
437		if ((pwr & DP_SET_POWER_MASK) != DP_SET_POWER_D0) {
438			pwr &= ~DP_SET_POWER_MASK;
439			pwr |=  DP_SET_POWER_D0;
440			drm_dp_dpcd_writeb(aux, DP_SET_POWER, pwr);
441		}
442	}
443
444	for (int nr = outp->dp.link_nr; nr; nr >>= 1) {
445		for (int rate = 0; rate < outp->dp.rate_nr; rate++) {
446			if (outp->dp.rate[rate].rate * nr >= min_rate) {
447				outp->dp.lt.nr = nr;
448				outp->dp.lt.bw = outp->dp.rate[rate].rate;
449				outp->dp.lt.mst = mst;
450				if (nouveau_dp_train_link(outp, false))
451					goto done;
452			}
453		}
454	}
455
456	ret = false;
457done:
458	mutex_unlock(&outp->dp.hpd_irq_lock);
459	return ret;
460}
461
462static bool
463nouveau_dp_link_check_locked(struct nouveau_encoder *outp)
464{
465	u8 link_status[DP_LINK_STATUS_SIZE];
 
 
 
466
467	if (!outp || !outp->dp.lt.nr)
468		return true;
 
469
470	if (drm_dp_dpcd_read_phy_link_status(&outp->conn->aux, DP_PHY_DPRX, link_status) < 0)
471		return false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
472
473	if (drm_dp_channel_eq_ok(link_status, outp->dp.lt.nr))
474		return true;
475
476	return nouveau_dp_train_link(outp, true);
477}
478
479bool
480nouveau_dp_link_check(struct nouveau_connector *nv_connector)
 
481{
482	struct nouveau_encoder *outp = nv_connector->dp_encoder;
483	bool link_ok = true;
 
 
 
 
 
 
 
 
 
 
 
 
484
485	if (outp) {
486		mutex_lock(&outp->dp.hpd_irq_lock);
487		if (outp->dp.lt.nr)
488			link_ok = nouveau_dp_link_check_locked(outp);
489		mutex_unlock(&outp->dp.hpd_irq_lock);
490	}
491
492	return link_ok;
493}
 
 
494
495void
496nouveau_dp_irq(struct work_struct *work)
497{
498	struct nouveau_connector *nv_connector =
499		container_of(work, typeof(*nv_connector), irq_work);
500	struct drm_connector *connector = &nv_connector->base;
501	struct nouveau_encoder *outp = find_encoder(connector, DCB_OUTPUT_DP);
502	struct nouveau_drm *drm = nouveau_drm(outp->base.base.dev);
503	struct nv50_mstm *mstm;
504	u64 hpd = 0;
505	int ret;
506
507	if (!outp)
508		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
509
510	mstm = outp->dp.mstm;
511	NV_DEBUG(drm, "service %s\n", connector->name);
512
513	mutex_lock(&outp->dp.hpd_irq_lock);
 
 
 
 
514
515	if (mstm && mstm->is_mst) {
516		if (!nv50_mstm_service(drm, nv_connector, mstm))
517			hpd |= NVIF_CONN_EVENT_V0_UNPLUG;
518	} else {
519		drm_dp_cec_irq(&nv_connector->aux);
520
521		if (nouveau_dp_has_sink_count(connector, outp)) {
522			ret = drm_dp_read_sink_count(&nv_connector->aux);
523			if (ret != outp->dp.sink_count)
524				hpd |= NVIF_CONN_EVENT_V0_PLUG;
525			if (ret >= 0)
526				outp->dp.sink_count = ret;
527		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
528	}
529
530	mutex_unlock(&outp->dp.hpd_irq_lock);
531
532	nouveau_connector_hpd(nv_connector, NVIF_CONN_EVENT_V0_IRQ | hpd);
533}
534
535/* TODO:
536 * - Validate against the DP caps advertised by the GPU (we don't check these
537 *   yet)
538 */
539enum drm_mode_status
540nv50_dp_mode_valid(struct nouveau_encoder *outp,
541		   const struct drm_display_mode *mode,
542		   unsigned *out_clock)
543{
544	const unsigned int min_clock = 25000;
545	unsigned int max_rate, mode_rate, ds_max_dotclock, clock = mode->clock;
546	/* Check with the minmum bpc always, so we can advertise better modes.
547	 * In particlar not doing this causes modes to be dropped on HDR
548	 * displays as we might check with a bpc of 16 even.
549	 */
550	const u8 bpp = 6 * 3;
551
552	if (mode->flags & DRM_MODE_FLAG_INTERLACE && !outp->caps.dp_interlace)
553		return MODE_NO_INTERLACE;
 
 
554
555	if ((mode->flags & DRM_MODE_FLAG_3D_MASK) == DRM_MODE_FLAG_3D_FRAME_PACKING)
556		clock *= 2;
557
558	max_rate = outp->dp.link_nr * outp->dp.link_bw;
559	mode_rate = DIV_ROUND_UP(clock * bpp, 8);
560	if (mode_rate > max_rate)
561		return MODE_CLOCK_HIGH;
562
563	ds_max_dotclock = drm_dp_downstream_max_dotclock(outp->dp.dpcd, outp->dp.downstream_ports);
564	if (ds_max_dotclock && clock > ds_max_dotclock)
565		return MODE_CLOCK_HIGH;
 
 
 
 
 
 
 
 
 
566
567	if (clock < min_clock)
568		return MODE_CLOCK_LOW;
 
569
570	if (out_clock)
571		*out_clock = clock;
572
573	return MODE_OK;
574}