xref: /linux/drivers/gpu/drm/msm/dp/dp_ctrl.c (revision 60684c2bd35064043360e6f716d1b7c20e967b7d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
4  */
5 
6 #define pr_fmt(fmt)	"[drm-dp] %s: " fmt, __func__
7 
8 #include <linux/types.h>
9 #include <linux/completion.h>
10 #include <linux/delay.h>
11 #include <linux/phy/phy.h>
12 #include <linux/phy/phy-dp.h>
13 #include <linux/pm_opp.h>
14 
15 #include <drm/display/drm_dp_helper.h>
16 #include <drm/drm_fixed.h>
17 #include <drm/drm_print.h>
18 
19 #include "dp_reg.h"
20 #include "dp_ctrl.h"
21 #include "dp_link.h"
22 
23 #define DP_KHZ_TO_HZ 1000
24 #define IDLE_PATTERN_COMPLETION_TIMEOUT_JIFFIES	(30 * HZ / 1000) /* 30 ms */
25 #define WAIT_FOR_VIDEO_READY_TIMEOUT_JIFFIES (HZ / 2)
26 
27 #define DP_CTRL_INTR_READY_FOR_VIDEO     BIT(0)
28 #define DP_CTRL_INTR_IDLE_PATTERN_SENT  BIT(3)
29 
30 #define MR_LINK_TRAINING1  0x8
31 #define MR_LINK_SYMBOL_ERM 0x80
32 #define MR_LINK_PRBS7 0x100
33 #define MR_LINK_CUSTOM80 0x200
34 #define MR_LINK_TRAINING4  0x40
35 
36 enum {
37 	DP_TRAINING_NONE,
38 	DP_TRAINING_1,
39 	DP_TRAINING_2,
40 };
41 
42 struct dp_tu_calc_input {
43 	u64 lclk;        /* 162, 270, 540 and 810 */
44 	u64 pclk_khz;    /* in KHz */
45 	u64 hactive;     /* active h-width */
46 	u64 hporch;      /* bp + fp + pulse */
47 	int nlanes;      /* no.of.lanes */
48 	int bpp;         /* bits */
49 	int pixel_enc;   /* 444, 420, 422 */
50 	int dsc_en;     /* dsc on/off */
51 	int async_en;   /* async mode */
52 	int fec_en;     /* fec */
53 	int compress_ratio; /* 2:1 = 200, 3:1 = 300, 3.75:1 = 375 */
54 	int num_of_dsc_slices; /* number of slices per line */
55 };
56 
57 struct dp_vc_tu_mapping_table {
58 	u32 vic;
59 	u8 lanes;
60 	u8 lrate; /* DP_LINK_RATE -> 162(6), 270(10), 540(20), 810 (30) */
61 	u8 bpp;
62 	u8 valid_boundary_link;
63 	u16 delay_start_link;
64 	bool boundary_moderation_en;
65 	u8 valid_lower_boundary_link;
66 	u8 upper_boundary_count;
67 	u8 lower_boundary_count;
68 	u8 tu_size_minus1;
69 };
70 
71 struct dp_ctrl_private {
72 	struct dp_ctrl dp_ctrl;
73 	struct drm_device *drm_dev;
74 	struct device *dev;
75 	struct drm_dp_aux *aux;
76 	struct dp_panel *panel;
77 	struct dp_link *link;
78 	struct dp_power *power;
79 	struct dp_parser *parser;
80 	struct dp_catalog *catalog;
81 
82 	struct completion idle_comp;
83 	struct completion video_comp;
84 };
85 
86 static int dp_aux_link_configure(struct drm_dp_aux *aux,
87 					struct dp_link_info *link)
88 {
89 	u8 values[2];
90 	int err;
91 
92 	values[0] = drm_dp_link_rate_to_bw_code(link->rate);
93 	values[1] = link->num_lanes;
94 
95 	if (link->capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
96 		values[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
97 
98 	err = drm_dp_dpcd_write(aux, DP_LINK_BW_SET, values, sizeof(values));
99 	if (err < 0)
100 		return err;
101 
102 	return 0;
103 }
104 
105 void dp_ctrl_push_idle(struct dp_ctrl *dp_ctrl)
106 {
107 	struct dp_ctrl_private *ctrl;
108 
109 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
110 
111 	reinit_completion(&ctrl->idle_comp);
112 	dp_catalog_ctrl_state_ctrl(ctrl->catalog, DP_STATE_CTRL_PUSH_IDLE);
113 
114 	if (!wait_for_completion_timeout(&ctrl->idle_comp,
115 			IDLE_PATTERN_COMPLETION_TIMEOUT_JIFFIES))
116 		pr_warn("PUSH_IDLE pattern timedout\n");
117 
118 	drm_dbg_dp(ctrl->drm_dev, "mainlink off\n");
119 }
120 
121 static void dp_ctrl_config_ctrl(struct dp_ctrl_private *ctrl)
122 {
123 	u32 config = 0, tbd;
124 	const u8 *dpcd = ctrl->panel->dpcd;
125 
126 	/* Default-> LSCLK DIV: 1/4 LCLK  */
127 	config |= (2 << DP_CONFIGURATION_CTRL_LSCLK_DIV_SHIFT);
128 
129 	/* Scrambler reset enable */
130 	if (drm_dp_alternate_scrambler_reset_cap(dpcd))
131 		config |= DP_CONFIGURATION_CTRL_ASSR;
132 
133 	tbd = dp_link_get_test_bits_depth(ctrl->link,
134 			ctrl->panel->dp_mode.bpp);
135 
136 	if (tbd == DP_TEST_BIT_DEPTH_UNKNOWN) {
137 		pr_debug("BIT_DEPTH not set. Configure default\n");
138 		tbd = DP_TEST_BIT_DEPTH_8;
139 	}
140 
141 	config |= tbd << DP_CONFIGURATION_CTRL_BPC_SHIFT;
142 
143 	/* Num of Lanes */
144 	config |= ((ctrl->link->link_params.num_lanes - 1)
145 			<< DP_CONFIGURATION_CTRL_NUM_OF_LANES_SHIFT);
146 
147 	if (drm_dp_enhanced_frame_cap(dpcd))
148 		config |= DP_CONFIGURATION_CTRL_ENHANCED_FRAMING;
149 
150 	config |= DP_CONFIGURATION_CTRL_P_INTERLACED; /* progressive video */
151 
152 	/* sync clock & static Mvid */
153 	config |= DP_CONFIGURATION_CTRL_STATIC_DYNAMIC_CN;
154 	config |= DP_CONFIGURATION_CTRL_SYNC_ASYNC_CLK;
155 
156 	dp_catalog_ctrl_config_ctrl(ctrl->catalog, config);
157 }
158 
159 static void dp_ctrl_configure_source_params(struct dp_ctrl_private *ctrl)
160 {
161 	u32 cc, tb;
162 
163 	dp_catalog_ctrl_lane_mapping(ctrl->catalog);
164 	dp_catalog_ctrl_mainlink_ctrl(ctrl->catalog, true);
165 
166 	dp_ctrl_config_ctrl(ctrl);
167 
168 	tb = dp_link_get_test_bits_depth(ctrl->link,
169 		ctrl->panel->dp_mode.bpp);
170 	cc = dp_link_get_colorimetry_config(ctrl->link);
171 	dp_catalog_ctrl_config_misc(ctrl->catalog, cc, tb);
172 	dp_panel_timing_cfg(ctrl->panel);
173 }
174 
175 /*
176  * The structure and few functions present below are IP/Hardware
177  * specific implementation. Most of the implementation will not
178  * have coding comments
179  */
180 struct tu_algo_data {
181 	s64 lclk_fp;
182 	s64 pclk_fp;
183 	s64 lwidth;
184 	s64 lwidth_fp;
185 	s64 hbp_relative_to_pclk;
186 	s64 hbp_relative_to_pclk_fp;
187 	int nlanes;
188 	int bpp;
189 	int pixelEnc;
190 	int dsc_en;
191 	int async_en;
192 	int bpc;
193 
194 	uint delay_start_link_extra_pixclk;
195 	int extra_buffer_margin;
196 	s64 ratio_fp;
197 	s64 original_ratio_fp;
198 
199 	s64 err_fp;
200 	s64 n_err_fp;
201 	s64 n_n_err_fp;
202 	int tu_size;
203 	int tu_size_desired;
204 	int tu_size_minus1;
205 
206 	int valid_boundary_link;
207 	s64 resulting_valid_fp;
208 	s64 total_valid_fp;
209 	s64 effective_valid_fp;
210 	s64 effective_valid_recorded_fp;
211 	int n_tus;
212 	int n_tus_per_lane;
213 	int paired_tus;
214 	int remainder_tus;
215 	int remainder_tus_upper;
216 	int remainder_tus_lower;
217 	int extra_bytes;
218 	int filler_size;
219 	int delay_start_link;
220 
221 	int extra_pclk_cycles;
222 	int extra_pclk_cycles_in_link_clk;
223 	s64 ratio_by_tu_fp;
224 	s64 average_valid2_fp;
225 	int new_valid_boundary_link;
226 	int remainder_symbols_exist;
227 	int n_symbols;
228 	s64 n_remainder_symbols_per_lane_fp;
229 	s64 last_partial_tu_fp;
230 	s64 TU_ratio_err_fp;
231 
232 	int n_tus_incl_last_incomplete_tu;
233 	int extra_pclk_cycles_tmp;
234 	int extra_pclk_cycles_in_link_clk_tmp;
235 	int extra_required_bytes_new_tmp;
236 	int filler_size_tmp;
237 	int lower_filler_size_tmp;
238 	int delay_start_link_tmp;
239 
240 	bool boundary_moderation_en;
241 	int boundary_mod_lower_err;
242 	int upper_boundary_count;
243 	int lower_boundary_count;
244 	int i_upper_boundary_count;
245 	int i_lower_boundary_count;
246 	int valid_lower_boundary_link;
247 	int even_distribution_BF;
248 	int even_distribution_legacy;
249 	int even_distribution;
250 	int min_hblank_violated;
251 	s64 delay_start_time_fp;
252 	s64 hbp_time_fp;
253 	s64 hactive_time_fp;
254 	s64 diff_abs_fp;
255 
256 	s64 ratio;
257 };
258 
259 static int _tu_param_compare(s64 a, s64 b)
260 {
261 	u32 a_sign;
262 	u32 b_sign;
263 	s64 a_temp, b_temp, minus_1;
264 
265 	if (a == b)
266 		return 0;
267 
268 	minus_1 = drm_fixp_from_fraction(-1, 1);
269 
270 	a_sign = (a >> 32) & 0x80000000 ? 1 : 0;
271 
272 	b_sign = (b >> 32) & 0x80000000 ? 1 : 0;
273 
274 	if (a_sign > b_sign)
275 		return 2;
276 	else if (b_sign > a_sign)
277 		return 1;
278 
279 	if (!a_sign && !b_sign) { /* positive */
280 		if (a > b)
281 			return 1;
282 		else
283 			return 2;
284 	} else { /* negative */
285 		a_temp = drm_fixp_mul(a, minus_1);
286 		b_temp = drm_fixp_mul(b, minus_1);
287 
288 		if (a_temp > b_temp)
289 			return 2;
290 		else
291 			return 1;
292 	}
293 }
294 
295 static void dp_panel_update_tu_timings(struct dp_tu_calc_input *in,
296 					struct tu_algo_data *tu)
297 {
298 	int nlanes = in->nlanes;
299 	int dsc_num_slices = in->num_of_dsc_slices;
300 	int dsc_num_bytes  = 0;
301 	int numerator;
302 	s64 pclk_dsc_fp;
303 	s64 dwidth_dsc_fp;
304 	s64 hbp_dsc_fp;
305 
306 	int tot_num_eoc_symbols = 0;
307 	int tot_num_hor_bytes   = 0;
308 	int tot_num_dummy_bytes = 0;
309 	int dwidth_dsc_bytes    = 0;
310 	int  eoc_bytes           = 0;
311 
312 	s64 temp1_fp, temp2_fp, temp3_fp;
313 
314 	tu->lclk_fp              = drm_fixp_from_fraction(in->lclk, 1);
315 	tu->pclk_fp              = drm_fixp_from_fraction(in->pclk_khz, 1000);
316 	tu->lwidth               = in->hactive;
317 	tu->hbp_relative_to_pclk = in->hporch;
318 	tu->nlanes               = in->nlanes;
319 	tu->bpp                  = in->bpp;
320 	tu->pixelEnc             = in->pixel_enc;
321 	tu->dsc_en               = in->dsc_en;
322 	tu->async_en             = in->async_en;
323 	tu->lwidth_fp            = drm_fixp_from_fraction(in->hactive, 1);
324 	tu->hbp_relative_to_pclk_fp = drm_fixp_from_fraction(in->hporch, 1);
325 
326 	if (tu->pixelEnc == 420) {
327 		temp1_fp = drm_fixp_from_fraction(2, 1);
328 		tu->pclk_fp = drm_fixp_div(tu->pclk_fp, temp1_fp);
329 		tu->lwidth_fp = drm_fixp_div(tu->lwidth_fp, temp1_fp);
330 		tu->hbp_relative_to_pclk_fp =
331 				drm_fixp_div(tu->hbp_relative_to_pclk_fp, 2);
332 	}
333 
334 	if (tu->pixelEnc == 422) {
335 		switch (tu->bpp) {
336 		case 24:
337 			tu->bpp = 16;
338 			tu->bpc = 8;
339 			break;
340 		case 30:
341 			tu->bpp = 20;
342 			tu->bpc = 10;
343 			break;
344 		default:
345 			tu->bpp = 16;
346 			tu->bpc = 8;
347 			break;
348 		}
349 	} else {
350 		tu->bpc = tu->bpp/3;
351 	}
352 
353 	if (!in->dsc_en)
354 		goto fec_check;
355 
356 	temp1_fp = drm_fixp_from_fraction(in->compress_ratio, 100);
357 	temp2_fp = drm_fixp_from_fraction(in->bpp, 1);
358 	temp3_fp = drm_fixp_div(temp2_fp, temp1_fp);
359 	temp2_fp = drm_fixp_mul(tu->lwidth_fp, temp3_fp);
360 
361 	temp1_fp = drm_fixp_from_fraction(8, 1);
362 	temp3_fp = drm_fixp_div(temp2_fp, temp1_fp);
363 
364 	numerator = drm_fixp2int(temp3_fp);
365 
366 	dsc_num_bytes  = numerator / dsc_num_slices;
367 	eoc_bytes           = dsc_num_bytes % nlanes;
368 	tot_num_eoc_symbols = nlanes * dsc_num_slices;
369 	tot_num_hor_bytes   = dsc_num_bytes * dsc_num_slices;
370 	tot_num_dummy_bytes = (nlanes - eoc_bytes) * dsc_num_slices;
371 
372 	if (dsc_num_bytes == 0)
373 		pr_info("incorrect no of bytes per slice=%d\n", dsc_num_bytes);
374 
375 	dwidth_dsc_bytes = (tot_num_hor_bytes +
376 				tot_num_eoc_symbols +
377 				(eoc_bytes == 0 ? 0 : tot_num_dummy_bytes));
378 
379 	dwidth_dsc_fp = drm_fixp_from_fraction(dwidth_dsc_bytes, 3);
380 
381 	temp2_fp = drm_fixp_mul(tu->pclk_fp, dwidth_dsc_fp);
382 	temp1_fp = drm_fixp_div(temp2_fp, tu->lwidth_fp);
383 	pclk_dsc_fp = temp1_fp;
384 
385 	temp1_fp = drm_fixp_div(pclk_dsc_fp, tu->pclk_fp);
386 	temp2_fp = drm_fixp_mul(tu->hbp_relative_to_pclk_fp, temp1_fp);
387 	hbp_dsc_fp = temp2_fp;
388 
389 	/* output */
390 	tu->pclk_fp = pclk_dsc_fp;
391 	tu->lwidth_fp = dwidth_dsc_fp;
392 	tu->hbp_relative_to_pclk_fp = hbp_dsc_fp;
393 
394 fec_check:
395 	if (in->fec_en) {
396 		temp1_fp = drm_fixp_from_fraction(976, 1000); /* 0.976 */
397 		tu->lclk_fp = drm_fixp_mul(tu->lclk_fp, temp1_fp);
398 	}
399 }
400 
401 static void _tu_valid_boundary_calc(struct tu_algo_data *tu)
402 {
403 	s64 temp1_fp, temp2_fp, temp, temp1, temp2;
404 	int compare_result_1, compare_result_2, compare_result_3;
405 
406 	temp1_fp = drm_fixp_from_fraction(tu->tu_size, 1);
407 	temp2_fp = drm_fixp_mul(tu->ratio_fp, temp1_fp);
408 
409 	tu->new_valid_boundary_link = drm_fixp2int_ceil(temp2_fp);
410 
411 	temp = (tu->i_upper_boundary_count *
412 				tu->new_valid_boundary_link +
413 				tu->i_lower_boundary_count *
414 				(tu->new_valid_boundary_link-1));
415 	tu->average_valid2_fp = drm_fixp_from_fraction(temp,
416 					(tu->i_upper_boundary_count +
417 					tu->i_lower_boundary_count));
418 
419 	temp1_fp = drm_fixp_from_fraction(tu->bpp, 8);
420 	temp2_fp = tu->lwidth_fp;
421 	temp1_fp = drm_fixp_mul(temp2_fp, temp1_fp);
422 	temp2_fp = drm_fixp_div(temp1_fp, tu->average_valid2_fp);
423 	tu->n_tus = drm_fixp2int(temp2_fp);
424 	if ((temp2_fp & 0xFFFFFFFF) > 0xFFFFF000)
425 		tu->n_tus += 1;
426 
427 	temp1_fp = drm_fixp_from_fraction(tu->n_tus, 1);
428 	temp2_fp = drm_fixp_mul(temp1_fp, tu->average_valid2_fp);
429 	temp1_fp = drm_fixp_from_fraction(tu->n_symbols, 1);
430 	temp2_fp = temp1_fp - temp2_fp;
431 	temp1_fp = drm_fixp_from_fraction(tu->nlanes, 1);
432 	temp2_fp = drm_fixp_div(temp2_fp, temp1_fp);
433 	tu->n_remainder_symbols_per_lane_fp = temp2_fp;
434 
435 	temp1_fp = drm_fixp_from_fraction(tu->tu_size, 1);
436 	tu->last_partial_tu_fp =
437 			drm_fixp_div(tu->n_remainder_symbols_per_lane_fp,
438 					temp1_fp);
439 
440 	if (tu->n_remainder_symbols_per_lane_fp != 0)
441 		tu->remainder_symbols_exist = 1;
442 	else
443 		tu->remainder_symbols_exist = 0;
444 
445 	temp1_fp = drm_fixp_from_fraction(tu->n_tus, tu->nlanes);
446 	tu->n_tus_per_lane = drm_fixp2int(temp1_fp);
447 
448 	tu->paired_tus = (int)((tu->n_tus_per_lane) /
449 					(tu->i_upper_boundary_count +
450 					 tu->i_lower_boundary_count));
451 
452 	tu->remainder_tus = tu->n_tus_per_lane - tu->paired_tus *
453 						(tu->i_upper_boundary_count +
454 						tu->i_lower_boundary_count);
455 
456 	if ((tu->remainder_tus - tu->i_upper_boundary_count) > 0) {
457 		tu->remainder_tus_upper = tu->i_upper_boundary_count;
458 		tu->remainder_tus_lower = tu->remainder_tus -
459 						tu->i_upper_boundary_count;
460 	} else {
461 		tu->remainder_tus_upper = tu->remainder_tus;
462 		tu->remainder_tus_lower = 0;
463 	}
464 
465 	temp = tu->paired_tus * (tu->i_upper_boundary_count *
466 				tu->new_valid_boundary_link +
467 				tu->i_lower_boundary_count *
468 				(tu->new_valid_boundary_link - 1)) +
469 				(tu->remainder_tus_upper *
470 				 tu->new_valid_boundary_link) +
471 				(tu->remainder_tus_lower *
472 				(tu->new_valid_boundary_link - 1));
473 	tu->total_valid_fp = drm_fixp_from_fraction(temp, 1);
474 
475 	if (tu->remainder_symbols_exist) {
476 		temp1_fp = tu->total_valid_fp +
477 				tu->n_remainder_symbols_per_lane_fp;
478 		temp2_fp = drm_fixp_from_fraction(tu->n_tus_per_lane, 1);
479 		temp2_fp = temp2_fp + tu->last_partial_tu_fp;
480 		temp1_fp = drm_fixp_div(temp1_fp, temp2_fp);
481 	} else {
482 		temp2_fp = drm_fixp_from_fraction(tu->n_tus_per_lane, 1);
483 		temp1_fp = drm_fixp_div(tu->total_valid_fp, temp2_fp);
484 	}
485 	tu->effective_valid_fp = temp1_fp;
486 
487 	temp1_fp = drm_fixp_from_fraction(tu->tu_size, 1);
488 	temp2_fp = drm_fixp_mul(tu->ratio_fp, temp1_fp);
489 	tu->n_n_err_fp = tu->effective_valid_fp - temp2_fp;
490 
491 	temp1_fp = drm_fixp_from_fraction(tu->tu_size, 1);
492 	temp2_fp = drm_fixp_mul(tu->ratio_fp, temp1_fp);
493 	tu->n_err_fp = tu->average_valid2_fp - temp2_fp;
494 
495 	tu->even_distribution = tu->n_tus % tu->nlanes == 0 ? 1 : 0;
496 
497 	temp1_fp = drm_fixp_from_fraction(tu->bpp, 8);
498 	temp2_fp = tu->lwidth_fp;
499 	temp1_fp = drm_fixp_mul(temp2_fp, temp1_fp);
500 	temp2_fp = drm_fixp_div(temp1_fp, tu->average_valid2_fp);
501 
502 	if (temp2_fp)
503 		tu->n_tus_incl_last_incomplete_tu = drm_fixp2int_ceil(temp2_fp);
504 	else
505 		tu->n_tus_incl_last_incomplete_tu = 0;
506 
507 	temp1 = 0;
508 	temp1_fp = drm_fixp_from_fraction(tu->tu_size, 1);
509 	temp2_fp = drm_fixp_mul(tu->original_ratio_fp, temp1_fp);
510 	temp1_fp = tu->average_valid2_fp - temp2_fp;
511 	temp2_fp = drm_fixp_from_fraction(tu->n_tus_incl_last_incomplete_tu, 1);
512 	temp1_fp = drm_fixp_mul(temp2_fp, temp1_fp);
513 
514 	if (temp1_fp)
515 		temp1 = drm_fixp2int_ceil(temp1_fp);
516 
517 	temp = tu->i_upper_boundary_count * tu->nlanes;
518 	temp1_fp = drm_fixp_from_fraction(tu->tu_size, 1);
519 	temp2_fp = drm_fixp_mul(tu->original_ratio_fp, temp1_fp);
520 	temp1_fp = drm_fixp_from_fraction(tu->new_valid_boundary_link, 1);
521 	temp2_fp = temp1_fp - temp2_fp;
522 	temp1_fp = drm_fixp_from_fraction(temp, 1);
523 	temp2_fp = drm_fixp_mul(temp1_fp, temp2_fp);
524 
525 	if (temp2_fp)
526 		temp2 = drm_fixp2int_ceil(temp2_fp);
527 	else
528 		temp2 = 0;
529 	tu->extra_required_bytes_new_tmp = (int)(temp1 + temp2);
530 
531 	temp1_fp = drm_fixp_from_fraction(8, tu->bpp);
532 	temp2_fp = drm_fixp_from_fraction(
533 	tu->extra_required_bytes_new_tmp, 1);
534 	temp1_fp = drm_fixp_mul(temp2_fp, temp1_fp);
535 
536 	if (temp1_fp)
537 		tu->extra_pclk_cycles_tmp = drm_fixp2int_ceil(temp1_fp);
538 	else
539 		tu->extra_pclk_cycles_tmp = 0;
540 
541 	temp1_fp = drm_fixp_from_fraction(tu->extra_pclk_cycles_tmp, 1);
542 	temp2_fp = drm_fixp_div(tu->lclk_fp, tu->pclk_fp);
543 	temp1_fp = drm_fixp_mul(temp1_fp, temp2_fp);
544 
545 	if (temp1_fp)
546 		tu->extra_pclk_cycles_in_link_clk_tmp =
547 						drm_fixp2int_ceil(temp1_fp);
548 	else
549 		tu->extra_pclk_cycles_in_link_clk_tmp = 0;
550 
551 	tu->filler_size_tmp = tu->tu_size - tu->new_valid_boundary_link;
552 
553 	tu->lower_filler_size_tmp = tu->filler_size_tmp + 1;
554 
555 	tu->delay_start_link_tmp = tu->extra_pclk_cycles_in_link_clk_tmp +
556 					tu->lower_filler_size_tmp +
557 					tu->extra_buffer_margin;
558 
559 	temp1_fp = drm_fixp_from_fraction(tu->delay_start_link_tmp, 1);
560 	tu->delay_start_time_fp = drm_fixp_div(temp1_fp, tu->lclk_fp);
561 
562 	compare_result_1 = _tu_param_compare(tu->n_n_err_fp, tu->diff_abs_fp);
563 	if (compare_result_1 == 2)
564 		compare_result_1 = 1;
565 	else
566 		compare_result_1 = 0;
567 
568 	compare_result_2 = _tu_param_compare(tu->n_n_err_fp, tu->err_fp);
569 	if (compare_result_2 == 2)
570 		compare_result_2 = 1;
571 	else
572 		compare_result_2 = 0;
573 
574 	compare_result_3 = _tu_param_compare(tu->hbp_time_fp,
575 					tu->delay_start_time_fp);
576 	if (compare_result_3 == 2)
577 		compare_result_3 = 0;
578 	else
579 		compare_result_3 = 1;
580 
581 	if (((tu->even_distribution == 1) ||
582 			((tu->even_distribution_BF == 0) &&
583 			(tu->even_distribution_legacy == 0))) &&
584 			tu->n_err_fp >= 0 && tu->n_n_err_fp >= 0 &&
585 			compare_result_2 &&
586 			(compare_result_1 || (tu->min_hblank_violated == 1)) &&
587 			(tu->new_valid_boundary_link - 1) > 0 &&
588 			compare_result_3 &&
589 			(tu->delay_start_link_tmp <= 1023)) {
590 		tu->upper_boundary_count = tu->i_upper_boundary_count;
591 		tu->lower_boundary_count = tu->i_lower_boundary_count;
592 		tu->err_fp = tu->n_n_err_fp;
593 		tu->boundary_moderation_en = true;
594 		tu->tu_size_desired = tu->tu_size;
595 		tu->valid_boundary_link = tu->new_valid_boundary_link;
596 		tu->effective_valid_recorded_fp = tu->effective_valid_fp;
597 		tu->even_distribution_BF = 1;
598 		tu->delay_start_link = tu->delay_start_link_tmp;
599 	} else if (tu->boundary_mod_lower_err == 0) {
600 		compare_result_1 = _tu_param_compare(tu->n_n_err_fp,
601 							tu->diff_abs_fp);
602 		if (compare_result_1 == 2)
603 			tu->boundary_mod_lower_err = 1;
604 	}
605 }
606 
607 static void _dp_ctrl_calc_tu(struct dp_ctrl_private *ctrl,
608 				struct dp_tu_calc_input *in,
609 				struct dp_vc_tu_mapping_table *tu_table)
610 {
611 	struct tu_algo_data *tu;
612 	int compare_result_1, compare_result_2;
613 	u64 temp = 0;
614 	s64 temp_fp = 0, temp1_fp = 0, temp2_fp = 0;
615 
616 	s64 LCLK_FAST_SKEW_fp = drm_fixp_from_fraction(6, 10000); /* 0.0006 */
617 	s64 const_p49_fp = drm_fixp_from_fraction(49, 100); /* 0.49 */
618 	s64 const_p56_fp = drm_fixp_from_fraction(56, 100); /* 0.56 */
619 	s64 RATIO_SCALE_fp = drm_fixp_from_fraction(1001, 1000);
620 
621 	u8 DP_BRUTE_FORCE = 1;
622 	s64 BRUTE_FORCE_THRESHOLD_fp = drm_fixp_from_fraction(1, 10); /* 0.1 */
623 	uint EXTRA_PIXCLK_CYCLE_DELAY = 4;
624 	uint HBLANK_MARGIN = 4;
625 
626 	tu = kzalloc(sizeof(*tu), GFP_KERNEL);
627 	if (!tu)
628 		return;
629 
630 	dp_panel_update_tu_timings(in, tu);
631 
632 	tu->err_fp = drm_fixp_from_fraction(1000, 1); /* 1000 */
633 
634 	temp1_fp = drm_fixp_from_fraction(4, 1);
635 	temp2_fp = drm_fixp_mul(temp1_fp, tu->lclk_fp);
636 	temp_fp = drm_fixp_div(temp2_fp, tu->pclk_fp);
637 	tu->extra_buffer_margin = drm_fixp2int_ceil(temp_fp);
638 
639 	temp1_fp = drm_fixp_from_fraction(tu->bpp, 8);
640 	temp2_fp = drm_fixp_mul(tu->pclk_fp, temp1_fp);
641 	temp1_fp = drm_fixp_from_fraction(tu->nlanes, 1);
642 	temp2_fp = drm_fixp_div(temp2_fp, temp1_fp);
643 	tu->ratio_fp = drm_fixp_div(temp2_fp, tu->lclk_fp);
644 
645 	tu->original_ratio_fp = tu->ratio_fp;
646 	tu->boundary_moderation_en = false;
647 	tu->upper_boundary_count = 0;
648 	tu->lower_boundary_count = 0;
649 	tu->i_upper_boundary_count = 0;
650 	tu->i_lower_boundary_count = 0;
651 	tu->valid_lower_boundary_link = 0;
652 	tu->even_distribution_BF = 0;
653 	tu->even_distribution_legacy = 0;
654 	tu->even_distribution = 0;
655 	tu->delay_start_time_fp = 0;
656 
657 	tu->err_fp = drm_fixp_from_fraction(1000, 1);
658 	tu->n_err_fp = 0;
659 	tu->n_n_err_fp = 0;
660 
661 	tu->ratio = drm_fixp2int(tu->ratio_fp);
662 	temp1_fp = drm_fixp_from_fraction(tu->nlanes, 1);
663 	div64_u64_rem(tu->lwidth_fp, temp1_fp, &temp2_fp);
664 	if (temp2_fp != 0 &&
665 			!tu->ratio && tu->dsc_en == 0) {
666 		tu->ratio_fp = drm_fixp_mul(tu->ratio_fp, RATIO_SCALE_fp);
667 		tu->ratio = drm_fixp2int(tu->ratio_fp);
668 		if (tu->ratio)
669 			tu->ratio_fp = drm_fixp_from_fraction(1, 1);
670 	}
671 
672 	if (tu->ratio > 1)
673 		tu->ratio = 1;
674 
675 	if (tu->ratio == 1)
676 		goto tu_size_calc;
677 
678 	compare_result_1 = _tu_param_compare(tu->ratio_fp, const_p49_fp);
679 	if (!compare_result_1 || compare_result_1 == 1)
680 		compare_result_1 = 1;
681 	else
682 		compare_result_1 = 0;
683 
684 	compare_result_2 = _tu_param_compare(tu->ratio_fp, const_p56_fp);
685 	if (!compare_result_2 || compare_result_2 == 2)
686 		compare_result_2 = 1;
687 	else
688 		compare_result_2 = 0;
689 
690 	if (tu->dsc_en && compare_result_1 && compare_result_2) {
691 		HBLANK_MARGIN += 4;
692 		drm_dbg_dp(ctrl->drm_dev,
693 			"increase HBLANK_MARGIN to %d\n", HBLANK_MARGIN);
694 	}
695 
696 tu_size_calc:
697 	for (tu->tu_size = 32; tu->tu_size <= 64; tu->tu_size++) {
698 		temp1_fp = drm_fixp_from_fraction(tu->tu_size, 1);
699 		temp2_fp = drm_fixp_mul(tu->ratio_fp, temp1_fp);
700 		temp = drm_fixp2int_ceil(temp2_fp);
701 		temp1_fp = drm_fixp_from_fraction(temp, 1);
702 		tu->n_err_fp = temp1_fp - temp2_fp;
703 
704 		if (tu->n_err_fp < tu->err_fp) {
705 			tu->err_fp = tu->n_err_fp;
706 			tu->tu_size_desired = tu->tu_size;
707 		}
708 	}
709 
710 	tu->tu_size_minus1 = tu->tu_size_desired - 1;
711 
712 	temp1_fp = drm_fixp_from_fraction(tu->tu_size_desired, 1);
713 	temp2_fp = drm_fixp_mul(tu->ratio_fp, temp1_fp);
714 	tu->valid_boundary_link = drm_fixp2int_ceil(temp2_fp);
715 
716 	temp1_fp = drm_fixp_from_fraction(tu->bpp, 8);
717 	temp2_fp = tu->lwidth_fp;
718 	temp2_fp = drm_fixp_mul(temp2_fp, temp1_fp);
719 
720 	temp1_fp = drm_fixp_from_fraction(tu->valid_boundary_link, 1);
721 	temp2_fp = drm_fixp_div(temp2_fp, temp1_fp);
722 	tu->n_tus = drm_fixp2int(temp2_fp);
723 	if ((temp2_fp & 0xFFFFFFFF) > 0xFFFFF000)
724 		tu->n_tus += 1;
725 
726 	tu->even_distribution_legacy = tu->n_tus % tu->nlanes == 0 ? 1 : 0;
727 
728 	drm_dbg_dp(ctrl->drm_dev,
729 			"n_sym = %d, num_of_tus = %d\n",
730 			tu->valid_boundary_link, tu->n_tus);
731 
732 	temp1_fp = drm_fixp_from_fraction(tu->tu_size_desired, 1);
733 	temp2_fp = drm_fixp_mul(tu->original_ratio_fp, temp1_fp);
734 	temp1_fp = drm_fixp_from_fraction(tu->valid_boundary_link, 1);
735 	temp2_fp = temp1_fp - temp2_fp;
736 	temp1_fp = drm_fixp_from_fraction(tu->n_tus + 1, 1);
737 	temp2_fp = drm_fixp_mul(temp1_fp, temp2_fp);
738 
739 	temp = drm_fixp2int(temp2_fp);
740 	if (temp && temp2_fp)
741 		tu->extra_bytes = drm_fixp2int_ceil(temp2_fp);
742 	else
743 		tu->extra_bytes = 0;
744 
745 	temp1_fp = drm_fixp_from_fraction(tu->extra_bytes, 1);
746 	temp2_fp = drm_fixp_from_fraction(8, tu->bpp);
747 	temp1_fp = drm_fixp_mul(temp1_fp, temp2_fp);
748 
749 	if (temp && temp1_fp)
750 		tu->extra_pclk_cycles = drm_fixp2int_ceil(temp1_fp);
751 	else
752 		tu->extra_pclk_cycles = drm_fixp2int(temp1_fp);
753 
754 	temp1_fp = drm_fixp_div(tu->lclk_fp, tu->pclk_fp);
755 	temp2_fp = drm_fixp_from_fraction(tu->extra_pclk_cycles, 1);
756 	temp1_fp = drm_fixp_mul(temp2_fp, temp1_fp);
757 
758 	if (temp1_fp)
759 		tu->extra_pclk_cycles_in_link_clk = drm_fixp2int_ceil(temp1_fp);
760 	else
761 		tu->extra_pclk_cycles_in_link_clk = drm_fixp2int(temp1_fp);
762 
763 	tu->filler_size = tu->tu_size_desired - tu->valid_boundary_link;
764 
765 	temp1_fp = drm_fixp_from_fraction(tu->tu_size_desired, 1);
766 	tu->ratio_by_tu_fp = drm_fixp_mul(tu->ratio_fp, temp1_fp);
767 
768 	tu->delay_start_link = tu->extra_pclk_cycles_in_link_clk +
769 				tu->filler_size + tu->extra_buffer_margin;
770 
771 	tu->resulting_valid_fp =
772 			drm_fixp_from_fraction(tu->valid_boundary_link, 1);
773 
774 	temp1_fp = drm_fixp_from_fraction(tu->tu_size_desired, 1);
775 	temp2_fp = drm_fixp_div(tu->resulting_valid_fp, temp1_fp);
776 	tu->TU_ratio_err_fp = temp2_fp - tu->original_ratio_fp;
777 
778 	temp1_fp = drm_fixp_from_fraction(HBLANK_MARGIN, 1);
779 	temp1_fp = tu->hbp_relative_to_pclk_fp - temp1_fp;
780 	tu->hbp_time_fp = drm_fixp_div(temp1_fp, tu->pclk_fp);
781 
782 	temp1_fp = drm_fixp_from_fraction(tu->delay_start_link, 1);
783 	tu->delay_start_time_fp = drm_fixp_div(temp1_fp, tu->lclk_fp);
784 
785 	compare_result_1 = _tu_param_compare(tu->hbp_time_fp,
786 					tu->delay_start_time_fp);
787 	if (compare_result_1 == 2) /* if (hbp_time_fp < delay_start_time_fp) */
788 		tu->min_hblank_violated = 1;
789 
790 	tu->hactive_time_fp = drm_fixp_div(tu->lwidth_fp, tu->pclk_fp);
791 
792 	compare_result_2 = _tu_param_compare(tu->hactive_time_fp,
793 						tu->delay_start_time_fp);
794 	if (compare_result_2 == 2)
795 		tu->min_hblank_violated = 1;
796 
797 	tu->delay_start_time_fp = 0;
798 
799 	/* brute force */
800 
801 	tu->delay_start_link_extra_pixclk = EXTRA_PIXCLK_CYCLE_DELAY;
802 	tu->diff_abs_fp = tu->resulting_valid_fp - tu->ratio_by_tu_fp;
803 
804 	temp = drm_fixp2int(tu->diff_abs_fp);
805 	if (!temp && tu->diff_abs_fp <= 0xffff)
806 		tu->diff_abs_fp = 0;
807 
808 	/* if(diff_abs < 0) diff_abs *= -1 */
809 	if (tu->diff_abs_fp < 0)
810 		tu->diff_abs_fp = drm_fixp_mul(tu->diff_abs_fp, -1);
811 
812 	tu->boundary_mod_lower_err = 0;
813 	if ((tu->diff_abs_fp != 0 &&
814 			((tu->diff_abs_fp > BRUTE_FORCE_THRESHOLD_fp) ||
815 			 (tu->even_distribution_legacy == 0) ||
816 			 (DP_BRUTE_FORCE == 1))) ||
817 			(tu->min_hblank_violated == 1)) {
818 		do {
819 			tu->err_fp = drm_fixp_from_fraction(1000, 1);
820 
821 			temp1_fp = drm_fixp_div(tu->lclk_fp, tu->pclk_fp);
822 			temp2_fp = drm_fixp_from_fraction(
823 					tu->delay_start_link_extra_pixclk, 1);
824 			temp1_fp = drm_fixp_mul(temp2_fp, temp1_fp);
825 
826 			if (temp1_fp)
827 				tu->extra_buffer_margin =
828 					drm_fixp2int_ceil(temp1_fp);
829 			else
830 				tu->extra_buffer_margin = 0;
831 
832 			temp1_fp = drm_fixp_from_fraction(tu->bpp, 8);
833 			temp1_fp = drm_fixp_mul(tu->lwidth_fp, temp1_fp);
834 
835 			if (temp1_fp)
836 				tu->n_symbols = drm_fixp2int_ceil(temp1_fp);
837 			else
838 				tu->n_symbols = 0;
839 
840 			for (tu->tu_size = 32; tu->tu_size <= 64; tu->tu_size++) {
841 				for (tu->i_upper_boundary_count = 1;
842 					tu->i_upper_boundary_count <= 15;
843 					tu->i_upper_boundary_count++) {
844 					for (tu->i_lower_boundary_count = 1;
845 						tu->i_lower_boundary_count <= 15;
846 						tu->i_lower_boundary_count++) {
847 						_tu_valid_boundary_calc(tu);
848 					}
849 				}
850 			}
851 			tu->delay_start_link_extra_pixclk--;
852 		} while (tu->boundary_moderation_en != true &&
853 			tu->boundary_mod_lower_err == 1 &&
854 			tu->delay_start_link_extra_pixclk != 0);
855 
856 		if (tu->boundary_moderation_en == true) {
857 			temp1_fp = drm_fixp_from_fraction(
858 					(tu->upper_boundary_count *
859 					tu->valid_boundary_link +
860 					tu->lower_boundary_count *
861 					(tu->valid_boundary_link - 1)), 1);
862 			temp2_fp = drm_fixp_from_fraction(
863 					(tu->upper_boundary_count +
864 					tu->lower_boundary_count), 1);
865 			tu->resulting_valid_fp =
866 					drm_fixp_div(temp1_fp, temp2_fp);
867 
868 			temp1_fp = drm_fixp_from_fraction(
869 					tu->tu_size_desired, 1);
870 			tu->ratio_by_tu_fp =
871 				drm_fixp_mul(tu->original_ratio_fp, temp1_fp);
872 
873 			tu->valid_lower_boundary_link =
874 				tu->valid_boundary_link - 1;
875 
876 			temp1_fp = drm_fixp_from_fraction(tu->bpp, 8);
877 			temp1_fp = drm_fixp_mul(tu->lwidth_fp, temp1_fp);
878 			temp2_fp = drm_fixp_div(temp1_fp,
879 						tu->resulting_valid_fp);
880 			tu->n_tus = drm_fixp2int(temp2_fp);
881 
882 			tu->tu_size_minus1 = tu->tu_size_desired - 1;
883 			tu->even_distribution_BF = 1;
884 
885 			temp1_fp =
886 				drm_fixp_from_fraction(tu->tu_size_desired, 1);
887 			temp2_fp =
888 				drm_fixp_div(tu->resulting_valid_fp, temp1_fp);
889 			tu->TU_ratio_err_fp = temp2_fp - tu->original_ratio_fp;
890 		}
891 	}
892 
893 	temp2_fp = drm_fixp_mul(LCLK_FAST_SKEW_fp, tu->lwidth_fp);
894 
895 	if (temp2_fp)
896 		temp = drm_fixp2int_ceil(temp2_fp);
897 	else
898 		temp = 0;
899 
900 	temp1_fp = drm_fixp_from_fraction(tu->nlanes, 1);
901 	temp2_fp = drm_fixp_mul(tu->original_ratio_fp, temp1_fp);
902 	temp1_fp = drm_fixp_from_fraction(tu->bpp, 8);
903 	temp2_fp = drm_fixp_div(temp1_fp, temp2_fp);
904 	temp1_fp = drm_fixp_from_fraction(temp, 1);
905 	temp2_fp = drm_fixp_mul(temp1_fp, temp2_fp);
906 	temp = drm_fixp2int(temp2_fp);
907 
908 	if (tu->async_en)
909 		tu->delay_start_link += (int)temp;
910 
911 	temp1_fp = drm_fixp_from_fraction(tu->delay_start_link, 1);
912 	tu->delay_start_time_fp = drm_fixp_div(temp1_fp, tu->lclk_fp);
913 
914 	/* OUTPUTS */
915 	tu_table->valid_boundary_link       = tu->valid_boundary_link;
916 	tu_table->delay_start_link          = tu->delay_start_link;
917 	tu_table->boundary_moderation_en    = tu->boundary_moderation_en;
918 	tu_table->valid_lower_boundary_link = tu->valid_lower_boundary_link;
919 	tu_table->upper_boundary_count      = tu->upper_boundary_count;
920 	tu_table->lower_boundary_count      = tu->lower_boundary_count;
921 	tu_table->tu_size_minus1            = tu->tu_size_minus1;
922 
923 	drm_dbg_dp(ctrl->drm_dev, "TU: valid_boundary_link: %d\n",
924 				tu_table->valid_boundary_link);
925 	drm_dbg_dp(ctrl->drm_dev, "TU: delay_start_link: %d\n",
926 				tu_table->delay_start_link);
927 	drm_dbg_dp(ctrl->drm_dev, "TU: boundary_moderation_en: %d\n",
928 			tu_table->boundary_moderation_en);
929 	drm_dbg_dp(ctrl->drm_dev, "TU: valid_lower_boundary_link: %d\n",
930 			tu_table->valid_lower_boundary_link);
931 	drm_dbg_dp(ctrl->drm_dev, "TU: upper_boundary_count: %d\n",
932 			tu_table->upper_boundary_count);
933 	drm_dbg_dp(ctrl->drm_dev, "TU: lower_boundary_count: %d\n",
934 			tu_table->lower_boundary_count);
935 	drm_dbg_dp(ctrl->drm_dev, "TU: tu_size_minus1: %d\n",
936 			tu_table->tu_size_minus1);
937 
938 	kfree(tu);
939 }
940 
941 static void dp_ctrl_calc_tu_parameters(struct dp_ctrl_private *ctrl,
942 		struct dp_vc_tu_mapping_table *tu_table)
943 {
944 	struct dp_tu_calc_input in;
945 	struct drm_display_mode *drm_mode;
946 
947 	drm_mode = &ctrl->panel->dp_mode.drm_mode;
948 
949 	in.lclk = ctrl->link->link_params.rate / 1000;
950 	in.pclk_khz = drm_mode->clock;
951 	in.hactive = drm_mode->hdisplay;
952 	in.hporch = drm_mode->htotal - drm_mode->hdisplay;
953 	in.nlanes = ctrl->link->link_params.num_lanes;
954 	in.bpp = ctrl->panel->dp_mode.bpp;
955 	in.pixel_enc = 444;
956 	in.dsc_en = 0;
957 	in.async_en = 0;
958 	in.fec_en = 0;
959 	in.num_of_dsc_slices = 0;
960 	in.compress_ratio = 100;
961 
962 	_dp_ctrl_calc_tu(ctrl, &in, tu_table);
963 }
964 
965 static void dp_ctrl_setup_tr_unit(struct dp_ctrl_private *ctrl)
966 {
967 	u32 dp_tu = 0x0;
968 	u32 valid_boundary = 0x0;
969 	u32 valid_boundary2 = 0x0;
970 	struct dp_vc_tu_mapping_table tu_calc_table;
971 
972 	dp_ctrl_calc_tu_parameters(ctrl, &tu_calc_table);
973 
974 	dp_tu |= tu_calc_table.tu_size_minus1;
975 	valid_boundary |= tu_calc_table.valid_boundary_link;
976 	valid_boundary |= (tu_calc_table.delay_start_link << 16);
977 
978 	valid_boundary2 |= (tu_calc_table.valid_lower_boundary_link << 1);
979 	valid_boundary2 |= (tu_calc_table.upper_boundary_count << 16);
980 	valid_boundary2 |= (tu_calc_table.lower_boundary_count << 20);
981 
982 	if (tu_calc_table.boundary_moderation_en)
983 		valid_boundary2 |= BIT(0);
984 
985 	pr_debug("dp_tu=0x%x, valid_boundary=0x%x, valid_boundary2=0x%x\n",
986 			dp_tu, valid_boundary, valid_boundary2);
987 
988 	dp_catalog_ctrl_update_transfer_unit(ctrl->catalog,
989 				dp_tu, valid_boundary, valid_boundary2);
990 }
991 
992 static int dp_ctrl_wait4video_ready(struct dp_ctrl_private *ctrl)
993 {
994 	int ret = 0;
995 
996 	if (!wait_for_completion_timeout(&ctrl->video_comp,
997 				WAIT_FOR_VIDEO_READY_TIMEOUT_JIFFIES)) {
998 		DRM_ERROR("wait4video timedout\n");
999 		ret = -ETIMEDOUT;
1000 	}
1001 	return ret;
1002 }
1003 
1004 static int dp_ctrl_update_vx_px(struct dp_ctrl_private *ctrl)
1005 {
1006 	struct dp_link *link = ctrl->link;
1007 	int ret = 0, lane, lane_cnt;
1008 	u8 buf[4];
1009 	u32 max_level_reached = 0;
1010 	u32 voltage_swing_level = link->phy_params.v_level;
1011 	u32 pre_emphasis_level = link->phy_params.p_level;
1012 
1013 	drm_dbg_dp(ctrl->drm_dev,
1014 		"voltage level: %d emphasis level: %d\n",
1015 			voltage_swing_level, pre_emphasis_level);
1016 	ret = dp_catalog_ctrl_update_vx_px(ctrl->catalog,
1017 		voltage_swing_level, pre_emphasis_level);
1018 
1019 	if (ret)
1020 		return ret;
1021 
1022 	if (voltage_swing_level >= DP_TRAIN_VOLTAGE_SWING_MAX) {
1023 		drm_dbg_dp(ctrl->drm_dev,
1024 				"max. voltage swing level reached %d\n",
1025 				voltage_swing_level);
1026 		max_level_reached |= DP_TRAIN_MAX_SWING_REACHED;
1027 	}
1028 
1029 	if (pre_emphasis_level >= DP_TRAIN_PRE_EMPHASIS_MAX) {
1030 		drm_dbg_dp(ctrl->drm_dev,
1031 				"max. pre-emphasis level reached %d\n",
1032 				pre_emphasis_level);
1033 		max_level_reached  |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
1034 	}
1035 
1036 	pre_emphasis_level <<= DP_TRAIN_PRE_EMPHASIS_SHIFT;
1037 
1038 	lane_cnt = ctrl->link->link_params.num_lanes;
1039 	for (lane = 0; lane < lane_cnt; lane++)
1040 		buf[lane] = voltage_swing_level | pre_emphasis_level
1041 				| max_level_reached;
1042 
1043 	drm_dbg_dp(ctrl->drm_dev, "sink: p|v=0x%x\n",
1044 			voltage_swing_level | pre_emphasis_level);
1045 	ret = drm_dp_dpcd_write(ctrl->aux, DP_TRAINING_LANE0_SET,
1046 					buf, lane_cnt);
1047 	if (ret == lane_cnt)
1048 		ret = 0;
1049 
1050 	return ret;
1051 }
1052 
1053 static bool dp_ctrl_train_pattern_set(struct dp_ctrl_private *ctrl,
1054 		u8 pattern)
1055 {
1056 	u8 buf;
1057 	int ret = 0;
1058 
1059 	drm_dbg_dp(ctrl->drm_dev, "sink: pattern=%x\n", pattern);
1060 
1061 	buf = pattern;
1062 
1063 	if (pattern && pattern != DP_TRAINING_PATTERN_4)
1064 		buf |= DP_LINK_SCRAMBLING_DISABLE;
1065 
1066 	ret = drm_dp_dpcd_writeb(ctrl->aux, DP_TRAINING_PATTERN_SET, buf);
1067 	return ret == 1;
1068 }
1069 
1070 static int dp_ctrl_read_link_status(struct dp_ctrl_private *ctrl,
1071 				    u8 *link_status)
1072 {
1073 	int ret = 0, len;
1074 
1075 	len = drm_dp_dpcd_read_link_status(ctrl->aux, link_status);
1076 	if (len != DP_LINK_STATUS_SIZE) {
1077 		DRM_ERROR("DP link status read failed, err: %d\n", len);
1078 		ret = -EINVAL;
1079 	}
1080 
1081 	return ret;
1082 }
1083 
1084 static int dp_ctrl_link_train_1(struct dp_ctrl_private *ctrl,
1085 			int *training_step)
1086 {
1087 	int tries, old_v_level, ret = 0;
1088 	u8 link_status[DP_LINK_STATUS_SIZE];
1089 	int const maximum_retries = 4;
1090 
1091 	dp_catalog_ctrl_state_ctrl(ctrl->catalog, 0);
1092 
1093 	*training_step = DP_TRAINING_1;
1094 
1095 	ret = dp_catalog_ctrl_set_pattern_state_bit(ctrl->catalog, 1);
1096 	if (ret)
1097 		return ret;
1098 	dp_ctrl_train_pattern_set(ctrl, DP_TRAINING_PATTERN_1 |
1099 		DP_LINK_SCRAMBLING_DISABLE);
1100 
1101 	ret = dp_ctrl_update_vx_px(ctrl);
1102 	if (ret)
1103 		return ret;
1104 
1105 	tries = 0;
1106 	old_v_level = ctrl->link->phy_params.v_level;
1107 	for (tries = 0; tries < maximum_retries; tries++) {
1108 		drm_dp_link_train_clock_recovery_delay(ctrl->aux, ctrl->panel->dpcd);
1109 
1110 		ret = dp_ctrl_read_link_status(ctrl, link_status);
1111 		if (ret)
1112 			return ret;
1113 
1114 		if (drm_dp_clock_recovery_ok(link_status,
1115 			ctrl->link->link_params.num_lanes)) {
1116 			return 0;
1117 		}
1118 
1119 		if (ctrl->link->phy_params.v_level >=
1120 			DP_TRAIN_VOLTAGE_SWING_MAX) {
1121 			DRM_ERROR_RATELIMITED("max v_level reached\n");
1122 			return -EAGAIN;
1123 		}
1124 
1125 		if (old_v_level != ctrl->link->phy_params.v_level) {
1126 			tries = 0;
1127 			old_v_level = ctrl->link->phy_params.v_level;
1128 		}
1129 
1130 		dp_link_adjust_levels(ctrl->link, link_status);
1131 		ret = dp_ctrl_update_vx_px(ctrl);
1132 		if (ret)
1133 			return ret;
1134 	}
1135 
1136 	DRM_ERROR("max tries reached\n");
1137 	return -ETIMEDOUT;
1138 }
1139 
1140 static int dp_ctrl_link_rate_down_shift(struct dp_ctrl_private *ctrl)
1141 {
1142 	int ret = 0;
1143 
1144 	switch (ctrl->link->link_params.rate) {
1145 	case 810000:
1146 		ctrl->link->link_params.rate = 540000;
1147 		break;
1148 	case 540000:
1149 		ctrl->link->link_params.rate = 270000;
1150 		break;
1151 	case 270000:
1152 		ctrl->link->link_params.rate = 162000;
1153 		break;
1154 	case 162000:
1155 	default:
1156 		ret = -EINVAL;
1157 		break;
1158 	}
1159 
1160 	if (!ret) {
1161 		drm_dbg_dp(ctrl->drm_dev, "new rate=0x%x\n",
1162 				ctrl->link->link_params.rate);
1163 	}
1164 
1165 	return ret;
1166 }
1167 
1168 static int dp_ctrl_link_lane_down_shift(struct dp_ctrl_private *ctrl)
1169 {
1170 
1171 	if (ctrl->link->link_params.num_lanes == 1)
1172 		return -1;
1173 
1174 	ctrl->link->link_params.num_lanes /= 2;
1175 	ctrl->link->link_params.rate = ctrl->panel->link_info.rate;
1176 
1177 	ctrl->link->phy_params.p_level = 0;
1178 	ctrl->link->phy_params.v_level = 0;
1179 
1180 	return 0;
1181 }
1182 
1183 static void dp_ctrl_clear_training_pattern(struct dp_ctrl_private *ctrl)
1184 {
1185 	dp_ctrl_train_pattern_set(ctrl, DP_TRAINING_PATTERN_DISABLE);
1186 	drm_dp_link_train_channel_eq_delay(ctrl->aux, ctrl->panel->dpcd);
1187 }
1188 
1189 static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,
1190 			int *training_step)
1191 {
1192 	int tries = 0, ret = 0;
1193 	u8 pattern;
1194 	u32 state_ctrl_bit;
1195 	int const maximum_retries = 5;
1196 	u8 link_status[DP_LINK_STATUS_SIZE];
1197 
1198 	dp_catalog_ctrl_state_ctrl(ctrl->catalog, 0);
1199 
1200 	*training_step = DP_TRAINING_2;
1201 
1202 	if (drm_dp_tps4_supported(ctrl->panel->dpcd)) {
1203 		pattern = DP_TRAINING_PATTERN_4;
1204 		state_ctrl_bit = 4;
1205 	} else if (drm_dp_tps3_supported(ctrl->panel->dpcd)) {
1206 		pattern = DP_TRAINING_PATTERN_3;
1207 		state_ctrl_bit = 3;
1208 	} else {
1209 		pattern = DP_TRAINING_PATTERN_2;
1210 		state_ctrl_bit = 2;
1211 	}
1212 
1213 	ret = dp_catalog_ctrl_set_pattern_state_bit(ctrl->catalog, state_ctrl_bit);
1214 	if (ret)
1215 		return ret;
1216 
1217 	dp_ctrl_train_pattern_set(ctrl, pattern);
1218 
1219 	for (tries = 0; tries <= maximum_retries; tries++) {
1220 		drm_dp_link_train_channel_eq_delay(ctrl->aux, ctrl->panel->dpcd);
1221 
1222 		ret = dp_ctrl_read_link_status(ctrl, link_status);
1223 		if (ret)
1224 			return ret;
1225 
1226 		if (drm_dp_channel_eq_ok(link_status,
1227 			ctrl->link->link_params.num_lanes)) {
1228 			return 0;
1229 		}
1230 
1231 		dp_link_adjust_levels(ctrl->link, link_status);
1232 		ret = dp_ctrl_update_vx_px(ctrl);
1233 		if (ret)
1234 			return ret;
1235 
1236 	}
1237 
1238 	return -ETIMEDOUT;
1239 }
1240 
1241 static int dp_ctrl_link_train(struct dp_ctrl_private *ctrl,
1242 			int *training_step)
1243 {
1244 	int ret = 0;
1245 	const u8 *dpcd = ctrl->panel->dpcd;
1246 	u8 encoding[] = { 0, DP_SET_ANSI_8B10B };
1247 	u8 assr;
1248 	struct dp_link_info link_info = {0};
1249 
1250 	dp_ctrl_config_ctrl(ctrl);
1251 
1252 	link_info.num_lanes = ctrl->link->link_params.num_lanes;
1253 	link_info.rate = ctrl->link->link_params.rate;
1254 	link_info.capabilities = DP_LINK_CAP_ENHANCED_FRAMING;
1255 
1256 	dp_aux_link_configure(ctrl->aux, &link_info);
1257 
1258 	if (drm_dp_max_downspread(dpcd))
1259 		encoding[0] |= DP_SPREAD_AMP_0_5;
1260 
1261 	/* config DOWNSPREAD_CTRL and MAIN_LINK_CHANNEL_CODING_SET */
1262 	drm_dp_dpcd_write(ctrl->aux, DP_DOWNSPREAD_CTRL, encoding, 2);
1263 
1264 	if (drm_dp_alternate_scrambler_reset_cap(dpcd)) {
1265 		assr = DP_ALTERNATE_SCRAMBLER_RESET_ENABLE;
1266 		drm_dp_dpcd_write(ctrl->aux, DP_EDP_CONFIGURATION_SET,
1267 				&assr, 1);
1268 	}
1269 
1270 	ret = dp_ctrl_link_train_1(ctrl, training_step);
1271 	if (ret) {
1272 		DRM_ERROR("link training #1 failed. ret=%d\n", ret);
1273 		goto end;
1274 	}
1275 
1276 	/* print success info as this is a result of user initiated action */
1277 	drm_dbg_dp(ctrl->drm_dev, "link training #1 successful\n");
1278 
1279 	ret = dp_ctrl_link_train_2(ctrl, training_step);
1280 	if (ret) {
1281 		DRM_ERROR("link training #2 failed. ret=%d\n", ret);
1282 		goto end;
1283 	}
1284 
1285 	/* print success info as this is a result of user initiated action */
1286 	drm_dbg_dp(ctrl->drm_dev, "link training #2 successful\n");
1287 
1288 end:
1289 	dp_catalog_ctrl_state_ctrl(ctrl->catalog, 0);
1290 
1291 	return ret;
1292 }
1293 
1294 static int dp_ctrl_setup_main_link(struct dp_ctrl_private *ctrl,
1295 			int *training_step)
1296 {
1297 	int ret = 0;
1298 
1299 	dp_catalog_ctrl_mainlink_ctrl(ctrl->catalog, true);
1300 
1301 	if (ctrl->link->sink_request & DP_TEST_LINK_PHY_TEST_PATTERN)
1302 		return ret;
1303 
1304 	/*
1305 	 * As part of previous calls, DP controller state might have
1306 	 * transitioned to PUSH_IDLE. In order to start transmitting
1307 	 * a link training pattern, we have to first do soft reset.
1308 	 */
1309 
1310 	ret = dp_ctrl_link_train(ctrl, training_step);
1311 
1312 	return ret;
1313 }
1314 
1315 static void dp_ctrl_set_clock_rate(struct dp_ctrl_private *ctrl,
1316 			enum dp_pm_type module, char *name, unsigned long rate)
1317 {
1318 	u32 num = ctrl->parser->mp[module].num_clk;
1319 	struct clk_bulk_data *cfg = ctrl->parser->mp[module].clocks;
1320 
1321 	while (num && strcmp(cfg->id, name)) {
1322 		num--;
1323 		cfg++;
1324 	}
1325 
1326 	drm_dbg_dp(ctrl->drm_dev, "setting rate=%lu on clk=%s\n",
1327 						rate, name);
1328 
1329 	if (num)
1330 		clk_set_rate(cfg->clk, rate);
1331 	else
1332 		DRM_ERROR("%s clock doesn't exit to set rate %lu\n",
1333 				name, rate);
1334 }
1335 
1336 static int dp_ctrl_enable_mainlink_clocks(struct dp_ctrl_private *ctrl)
1337 {
1338 	int ret = 0;
1339 	struct dp_io *dp_io = &ctrl->parser->io;
1340 	struct phy *phy = dp_io->phy;
1341 	struct phy_configure_opts_dp *opts_dp = &dp_io->phy_opts.dp;
1342 	const u8 *dpcd = ctrl->panel->dpcd;
1343 
1344 	opts_dp->lanes = ctrl->link->link_params.num_lanes;
1345 	opts_dp->link_rate = ctrl->link->link_params.rate / 100;
1346 	opts_dp->ssc = drm_dp_max_downspread(dpcd);
1347 
1348 	phy_configure(phy, &dp_io->phy_opts);
1349 	phy_power_on(phy);
1350 
1351 	dev_pm_opp_set_rate(ctrl->dev, ctrl->link->link_params.rate * 1000);
1352 	ret = dp_power_clk_enable(ctrl->power, DP_CTRL_PM, true);
1353 	if (ret)
1354 		DRM_ERROR("Unable to start link clocks. ret=%d\n", ret);
1355 
1356 	drm_dbg_dp(ctrl->drm_dev, "link rate=%d\n", ctrl->link->link_params.rate);
1357 
1358 	return ret;
1359 }
1360 
1361 void dp_ctrl_reset_irq_ctrl(struct dp_ctrl *dp_ctrl, bool enable)
1362 {
1363 	struct dp_ctrl_private *ctrl;
1364 
1365 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1366 
1367 	dp_catalog_ctrl_reset(ctrl->catalog);
1368 
1369 	/*
1370 	 * all dp controller programmable registers will not
1371 	 * be reset to default value after DP_SW_RESET
1372 	 * therefore interrupt mask bits have to be updated
1373 	 * to enable/disable interrupts
1374 	 */
1375 	dp_catalog_ctrl_enable_irq(ctrl->catalog, enable);
1376 }
1377 
1378 void dp_ctrl_phy_init(struct dp_ctrl *dp_ctrl)
1379 {
1380 	struct dp_ctrl_private *ctrl;
1381 	struct dp_io *dp_io;
1382 	struct phy *phy;
1383 
1384 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1385 	dp_io = &ctrl->parser->io;
1386 	phy = dp_io->phy;
1387 
1388 	dp_catalog_ctrl_phy_reset(ctrl->catalog);
1389 	phy_init(phy);
1390 
1391 	drm_dbg_dp(ctrl->drm_dev, "phy=%p init=%d power_on=%d\n",
1392 			phy, phy->init_count, phy->power_count);
1393 }
1394 
1395 void dp_ctrl_phy_exit(struct dp_ctrl *dp_ctrl)
1396 {
1397 	struct dp_ctrl_private *ctrl;
1398 	struct dp_io *dp_io;
1399 	struct phy *phy;
1400 
1401 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1402 	dp_io = &ctrl->parser->io;
1403 	phy = dp_io->phy;
1404 
1405 	dp_catalog_ctrl_phy_reset(ctrl->catalog);
1406 	phy_exit(phy);
1407 	drm_dbg_dp(ctrl->drm_dev, "phy=%p init=%d power_on=%d\n",
1408 			phy, phy->init_count, phy->power_count);
1409 }
1410 
1411 static bool dp_ctrl_use_fixed_nvid(struct dp_ctrl_private *ctrl)
1412 {
1413 	const u8 *dpcd = ctrl->panel->dpcd;
1414 
1415 	/*
1416 	 * For better interop experience, used a fixed NVID=0x8000
1417 	 * whenever connected to a VGA dongle downstream.
1418 	 */
1419 	if (drm_dp_is_branch(dpcd))
1420 		return (drm_dp_has_quirk(&ctrl->panel->desc,
1421 					 DP_DPCD_QUIRK_CONSTANT_N));
1422 
1423 	return false;
1424 }
1425 
1426 static int dp_ctrl_reinitialize_mainlink(struct dp_ctrl_private *ctrl)
1427 {
1428 	int ret = 0;
1429 	struct dp_io *dp_io = &ctrl->parser->io;
1430 	struct phy *phy = dp_io->phy;
1431 	struct phy_configure_opts_dp *opts_dp = &dp_io->phy_opts.dp;
1432 
1433 	dp_catalog_ctrl_mainlink_ctrl(ctrl->catalog, false);
1434 	opts_dp->lanes = ctrl->link->link_params.num_lanes;
1435 	phy_configure(phy, &dp_io->phy_opts);
1436 	/*
1437 	 * Disable and re-enable the mainlink clock since the
1438 	 * link clock might have been adjusted as part of the
1439 	 * link maintenance.
1440 	 */
1441 	dev_pm_opp_set_rate(ctrl->dev, 0);
1442 	ret = dp_power_clk_enable(ctrl->power, DP_CTRL_PM, false);
1443 	if (ret) {
1444 		DRM_ERROR("Failed to disable clocks. ret=%d\n", ret);
1445 		return ret;
1446 	}
1447 	phy_power_off(phy);
1448 	/* hw recommended delay before re-enabling clocks */
1449 	msleep(20);
1450 
1451 	ret = dp_ctrl_enable_mainlink_clocks(ctrl);
1452 	if (ret) {
1453 		DRM_ERROR("Failed to enable mainlink clks. ret=%d\n", ret);
1454 		return ret;
1455 	}
1456 
1457 	return ret;
1458 }
1459 
1460 static int dp_ctrl_deinitialize_mainlink(struct dp_ctrl_private *ctrl)
1461 {
1462 	struct dp_io *dp_io;
1463 	struct phy *phy;
1464 	int ret;
1465 
1466 	dp_io = &ctrl->parser->io;
1467 	phy = dp_io->phy;
1468 
1469 	dp_catalog_ctrl_mainlink_ctrl(ctrl->catalog, false);
1470 
1471 	dp_catalog_ctrl_reset(ctrl->catalog);
1472 
1473 	dev_pm_opp_set_rate(ctrl->dev, 0);
1474 	ret = dp_power_clk_enable(ctrl->power, DP_CTRL_PM, false);
1475 	if (ret) {
1476 		DRM_ERROR("Failed to disable link clocks. ret=%d\n", ret);
1477 	}
1478 
1479 	phy_power_off(phy);
1480 
1481 	/* aux channel down, reinit phy */
1482 	phy_exit(phy);
1483 	phy_init(phy);
1484 
1485 	drm_dbg_dp(ctrl->drm_dev, "phy=%p init=%d power_on=%d\n",
1486 			phy, phy->init_count, phy->power_count);
1487 	return 0;
1488 }
1489 
1490 static int dp_ctrl_link_maintenance(struct dp_ctrl_private *ctrl)
1491 {
1492 	int ret = 0;
1493 	int training_step = DP_TRAINING_NONE;
1494 
1495 	dp_ctrl_push_idle(&ctrl->dp_ctrl);
1496 
1497 	ctrl->link->phy_params.p_level = 0;
1498 	ctrl->link->phy_params.v_level = 0;
1499 
1500 	ret = dp_ctrl_setup_main_link(ctrl, &training_step);
1501 	if (ret)
1502 		goto end;
1503 
1504 	dp_ctrl_clear_training_pattern(ctrl);
1505 
1506 	dp_catalog_ctrl_state_ctrl(ctrl->catalog, DP_STATE_CTRL_SEND_VIDEO);
1507 
1508 	ret = dp_ctrl_wait4video_ready(ctrl);
1509 end:
1510 	return ret;
1511 }
1512 
1513 static bool dp_ctrl_send_phy_test_pattern(struct dp_ctrl_private *ctrl)
1514 {
1515 	bool success = false;
1516 	u32 pattern_sent = 0x0;
1517 	u32 pattern_requested = ctrl->link->phy_params.phy_test_pattern_sel;
1518 
1519 	drm_dbg_dp(ctrl->drm_dev, "request: 0x%x\n", pattern_requested);
1520 
1521 	if (dp_catalog_ctrl_update_vx_px(ctrl->catalog,
1522 			ctrl->link->phy_params.v_level,
1523 			ctrl->link->phy_params.p_level)) {
1524 		DRM_ERROR("Failed to set v/p levels\n");
1525 		return false;
1526 	}
1527 	dp_catalog_ctrl_send_phy_pattern(ctrl->catalog, pattern_requested);
1528 	dp_ctrl_update_vx_px(ctrl);
1529 	dp_link_send_test_response(ctrl->link);
1530 
1531 	pattern_sent = dp_catalog_ctrl_read_phy_pattern(ctrl->catalog);
1532 
1533 	switch (pattern_sent) {
1534 	case MR_LINK_TRAINING1:
1535 		success = (pattern_requested ==
1536 				DP_PHY_TEST_PATTERN_D10_2);
1537 		break;
1538 	case MR_LINK_SYMBOL_ERM:
1539 		success = ((pattern_requested ==
1540 			DP_PHY_TEST_PATTERN_ERROR_COUNT) ||
1541 				(pattern_requested ==
1542 				DP_PHY_TEST_PATTERN_CP2520));
1543 		break;
1544 	case MR_LINK_PRBS7:
1545 		success = (pattern_requested ==
1546 				DP_PHY_TEST_PATTERN_PRBS7);
1547 		break;
1548 	case MR_LINK_CUSTOM80:
1549 		success = (pattern_requested ==
1550 				DP_PHY_TEST_PATTERN_80BIT_CUSTOM);
1551 		break;
1552 	case MR_LINK_TRAINING4:
1553 		success = (pattern_requested ==
1554 				DP_PHY_TEST_PATTERN_SEL_MASK);
1555 		break;
1556 	default:
1557 		success = false;
1558 	}
1559 
1560 	drm_dbg_dp(ctrl->drm_dev, "%s: test->0x%x\n",
1561 		success ? "success" : "failed", pattern_requested);
1562 	return success;
1563 }
1564 
1565 static int dp_ctrl_process_phy_test_request(struct dp_ctrl_private *ctrl)
1566 {
1567 	int ret;
1568 	unsigned long pixel_rate;
1569 
1570 	if (!ctrl->link->phy_params.phy_test_pattern_sel) {
1571 		drm_dbg_dp(ctrl->drm_dev,
1572 			"no test pattern selected by sink\n");
1573 		return 0;
1574 	}
1575 
1576 	/*
1577 	 * The global reset will need DP link related clocks to be
1578 	 * running. Add the global reset just before disabling the
1579 	 * link clocks and core clocks.
1580 	 */
1581 	ret = dp_ctrl_off(&ctrl->dp_ctrl);
1582 	if (ret) {
1583 		DRM_ERROR("failed to disable DP controller\n");
1584 		return ret;
1585 	}
1586 
1587 	ret = dp_ctrl_on_link(&ctrl->dp_ctrl);
1588 	if (ret) {
1589 		DRM_ERROR("failed to enable DP link controller\n");
1590 		return ret;
1591 	}
1592 
1593 	pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
1594 	dp_ctrl_set_clock_rate(ctrl, DP_STREAM_PM, "stream_pixel", pixel_rate * 1000);
1595 
1596 	ret = dp_power_clk_enable(ctrl->power, DP_STREAM_PM, true);
1597 	if (ret) {
1598 		DRM_ERROR("Failed to start pixel clocks. ret=%d\n", ret);
1599 		return ret;
1600 	}
1601 
1602 	dp_ctrl_send_phy_test_pattern(ctrl);
1603 
1604 	return 0;
1605 }
1606 
1607 void dp_ctrl_handle_sink_request(struct dp_ctrl *dp_ctrl)
1608 {
1609 	struct dp_ctrl_private *ctrl;
1610 	u32 sink_request = 0x0;
1611 
1612 	if (!dp_ctrl) {
1613 		DRM_ERROR("invalid input\n");
1614 		return;
1615 	}
1616 
1617 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1618 	sink_request = ctrl->link->sink_request;
1619 
1620 	if (sink_request & DP_TEST_LINK_PHY_TEST_PATTERN) {
1621 		drm_dbg_dp(ctrl->drm_dev, "PHY_TEST_PATTERN request\n");
1622 		if (dp_ctrl_process_phy_test_request(ctrl)) {
1623 			DRM_ERROR("process phy_test_req failed\n");
1624 			return;
1625 		}
1626 	}
1627 
1628 	if (sink_request & DP_LINK_STATUS_UPDATED) {
1629 		if (dp_ctrl_link_maintenance(ctrl)) {
1630 			DRM_ERROR("LM failed: TEST_LINK_TRAINING\n");
1631 			return;
1632 		}
1633 	}
1634 
1635 	if (sink_request & DP_TEST_LINK_TRAINING) {
1636 		dp_link_send_test_response(ctrl->link);
1637 		if (dp_ctrl_link_maintenance(ctrl)) {
1638 			DRM_ERROR("LM failed: TEST_LINK_TRAINING\n");
1639 			return;
1640 		}
1641 	}
1642 }
1643 
1644 static bool dp_ctrl_clock_recovery_any_ok(
1645 			const u8 link_status[DP_LINK_STATUS_SIZE],
1646 			int lane_count)
1647 {
1648 	int reduced_cnt;
1649 
1650 	if (lane_count <= 1)
1651 		return false;
1652 
1653 	/*
1654 	 * only interested in the lane number after reduced
1655 	 * lane_count = 4, then only interested in 2 lanes
1656 	 * lane_count = 2, then only interested in 1 lane
1657 	 */
1658 	reduced_cnt = lane_count >> 1;
1659 
1660 	return drm_dp_clock_recovery_ok(link_status, reduced_cnt);
1661 }
1662 
1663 static bool dp_ctrl_channel_eq_ok(struct dp_ctrl_private *ctrl)
1664 {
1665 	u8 link_status[DP_LINK_STATUS_SIZE];
1666 	int num_lanes = ctrl->link->link_params.num_lanes;
1667 
1668 	dp_ctrl_read_link_status(ctrl, link_status);
1669 
1670 	return drm_dp_channel_eq_ok(link_status, num_lanes);
1671 }
1672 
1673 int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl)
1674 {
1675 	int rc = 0;
1676 	struct dp_ctrl_private *ctrl;
1677 	u32 rate;
1678 	int link_train_max_retries = 5;
1679 	u32 const phy_cts_pixel_clk_khz = 148500;
1680 	u8 link_status[DP_LINK_STATUS_SIZE];
1681 	unsigned int training_step;
1682 	unsigned long pixel_rate;
1683 
1684 	if (!dp_ctrl)
1685 		return -EINVAL;
1686 
1687 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1688 
1689 	rate = ctrl->panel->link_info.rate;
1690 	pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
1691 
1692 	dp_power_clk_enable(ctrl->power, DP_CORE_PM, true);
1693 
1694 	if (ctrl->link->sink_request & DP_TEST_LINK_PHY_TEST_PATTERN) {
1695 		drm_dbg_dp(ctrl->drm_dev,
1696 				"using phy test link parameters\n");
1697 		if (!pixel_rate)
1698 			pixel_rate = phy_cts_pixel_clk_khz;
1699 	} else {
1700 		ctrl->link->link_params.rate = rate;
1701 		ctrl->link->link_params.num_lanes =
1702 			ctrl->panel->link_info.num_lanes;
1703 	}
1704 
1705 	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%lu\n",
1706 		ctrl->link->link_params.rate, ctrl->link->link_params.num_lanes,
1707 		pixel_rate);
1708 
1709 	rc = dp_ctrl_enable_mainlink_clocks(ctrl);
1710 	if (rc)
1711 		return rc;
1712 
1713 	while (--link_train_max_retries) {
1714 		rc = dp_ctrl_reinitialize_mainlink(ctrl);
1715 		if (rc) {
1716 			DRM_ERROR("Failed to reinitialize mainlink. rc=%d\n",
1717 					rc);
1718 			break;
1719 		}
1720 
1721 		training_step = DP_TRAINING_NONE;
1722 		rc = dp_ctrl_setup_main_link(ctrl, &training_step);
1723 		if (rc == 0) {
1724 			/* training completed successfully */
1725 			break;
1726 		} else if (training_step == DP_TRAINING_1) {
1727 			/* link train_1 failed */
1728 			if (!dp_catalog_link_is_connected(ctrl->catalog))
1729 				break;
1730 
1731 			dp_ctrl_read_link_status(ctrl, link_status);
1732 
1733 			rc = dp_ctrl_link_rate_down_shift(ctrl);
1734 			if (rc < 0) { /* already in RBR = 1.6G */
1735 				if (dp_ctrl_clock_recovery_any_ok(link_status,
1736 					ctrl->link->link_params.num_lanes)) {
1737 					/*
1738 					 * some lanes are ready,
1739 					 * reduce lane number
1740 					 */
1741 					rc = dp_ctrl_link_lane_down_shift(ctrl);
1742 					if (rc < 0) { /* lane == 1 already */
1743 						/* end with failure */
1744 						break;
1745 					}
1746 				} else {
1747 					/* end with failure */
1748 					break; /* lane == 1 already */
1749 				}
1750 			}
1751 		} else if (training_step == DP_TRAINING_2) {
1752 			/* link train_2 failed */
1753 			if (!dp_catalog_link_is_connected(ctrl->catalog))
1754 				break;
1755 
1756 			dp_ctrl_read_link_status(ctrl, link_status);
1757 
1758 			if (!drm_dp_clock_recovery_ok(link_status,
1759 					ctrl->link->link_params.num_lanes))
1760 				rc = dp_ctrl_link_rate_down_shift(ctrl);
1761 			else
1762 				rc = dp_ctrl_link_lane_down_shift(ctrl);
1763 
1764 			if (rc < 0) {
1765 				/* end with failure */
1766 				break; /* lane == 1 already */
1767 			}
1768 
1769 			/* stop link training before start re training  */
1770 			dp_ctrl_clear_training_pattern(ctrl);
1771 		}
1772 	}
1773 
1774 	if (ctrl->link->sink_request & DP_TEST_LINK_PHY_TEST_PATTERN)
1775 		return rc;
1776 
1777 	if (rc == 0) {  /* link train successfully */
1778 		/*
1779 		 * do not stop train pattern here
1780 		 * stop link training at on_stream
1781 		 * to pass compliance test
1782 		 */
1783 	} else  {
1784 		/*
1785 		 * link training failed
1786 		 * end txing train pattern here
1787 		 */
1788 		dp_ctrl_clear_training_pattern(ctrl);
1789 
1790 		dp_ctrl_deinitialize_mainlink(ctrl);
1791 		rc = -ECONNRESET;
1792 	}
1793 
1794 	return rc;
1795 }
1796 
1797 static int dp_ctrl_link_retrain(struct dp_ctrl_private *ctrl)
1798 {
1799 	int training_step = DP_TRAINING_NONE;
1800 
1801 	return dp_ctrl_setup_main_link(ctrl, &training_step);
1802 }
1803 
1804 int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
1805 {
1806 	int ret = 0;
1807 	bool mainlink_ready = false;
1808 	struct dp_ctrl_private *ctrl;
1809 	unsigned long pixel_rate;
1810 	unsigned long pixel_rate_orig;
1811 
1812 	if (!dp_ctrl)
1813 		return -EINVAL;
1814 
1815 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1816 
1817 	pixel_rate = pixel_rate_orig = ctrl->panel->dp_mode.drm_mode.clock;
1818 
1819 	if (dp_ctrl->wide_bus_en)
1820 		pixel_rate >>= 1;
1821 
1822 	drm_dbg_dp(ctrl->drm_dev, "rate=%d, num_lanes=%d, pixel_rate=%lu\n",
1823 		ctrl->link->link_params.rate,
1824 		ctrl->link->link_params.num_lanes, pixel_rate);
1825 
1826 	if (!dp_power_clk_status(ctrl->power, DP_CTRL_PM)) { /* link clk is off */
1827 		ret = dp_ctrl_enable_mainlink_clocks(ctrl);
1828 		if (ret) {
1829 			DRM_ERROR("Failed to start link clocks. ret=%d\n", ret);
1830 			goto end;
1831 		}
1832 	}
1833 
1834 	dp_ctrl_set_clock_rate(ctrl, DP_STREAM_PM, "stream_pixel", pixel_rate * 1000);
1835 
1836 	ret = dp_power_clk_enable(ctrl->power, DP_STREAM_PM, true);
1837 	if (ret) {
1838 		DRM_ERROR("Unable to start pixel clocks. ret=%d\n", ret);
1839 		goto end;
1840 	}
1841 
1842 	if (force_link_train || !dp_ctrl_channel_eq_ok(ctrl))
1843 		dp_ctrl_link_retrain(ctrl);
1844 
1845 	/* stop txing train pattern to end link training */
1846 	dp_ctrl_clear_training_pattern(ctrl);
1847 
1848 	/*
1849 	 * Set up transfer unit values and set controller state to send
1850 	 * video.
1851 	 */
1852 	reinit_completion(&ctrl->video_comp);
1853 
1854 	dp_ctrl_configure_source_params(ctrl);
1855 
1856 	dp_catalog_ctrl_config_msa(ctrl->catalog,
1857 		ctrl->link->link_params.rate,
1858 		pixel_rate_orig, dp_ctrl_use_fixed_nvid(ctrl));
1859 
1860 	dp_ctrl_setup_tr_unit(ctrl);
1861 
1862 	dp_catalog_ctrl_state_ctrl(ctrl->catalog, DP_STATE_CTRL_SEND_VIDEO);
1863 
1864 	ret = dp_ctrl_wait4video_ready(ctrl);
1865 	if (ret)
1866 		return ret;
1867 
1868 	mainlink_ready = dp_catalog_ctrl_mainlink_ready(ctrl->catalog);
1869 	drm_dbg_dp(ctrl->drm_dev,
1870 		"mainlink %s\n", mainlink_ready ? "READY" : "NOT READY");
1871 
1872 end:
1873 	return ret;
1874 }
1875 
1876 int dp_ctrl_off_link_stream(struct dp_ctrl *dp_ctrl)
1877 {
1878 	struct dp_ctrl_private *ctrl;
1879 	struct dp_io *dp_io;
1880 	struct phy *phy;
1881 	int ret;
1882 
1883 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1884 	dp_io = &ctrl->parser->io;
1885 	phy = dp_io->phy;
1886 
1887 	/* set dongle to D3 (power off) mode */
1888 	dp_link_psm_config(ctrl->link, &ctrl->panel->link_info, true);
1889 
1890 	dp_catalog_ctrl_mainlink_ctrl(ctrl->catalog, false);
1891 
1892 	if (dp_power_clk_status(ctrl->power, DP_STREAM_PM)) {
1893 		ret = dp_power_clk_enable(ctrl->power, DP_STREAM_PM, false);
1894 		if (ret) {
1895 			DRM_ERROR("Failed to disable pclk. ret=%d\n", ret);
1896 			return ret;
1897 		}
1898 	}
1899 
1900 	dev_pm_opp_set_rate(ctrl->dev, 0);
1901 	ret = dp_power_clk_enable(ctrl->power, DP_CTRL_PM, false);
1902 	if (ret) {
1903 		DRM_ERROR("Failed to disable link clocks. ret=%d\n", ret);
1904 		return ret;
1905 	}
1906 
1907 	phy_power_off(phy);
1908 
1909 	/* aux channel down, reinit phy */
1910 	phy_exit(phy);
1911 	phy_init(phy);
1912 
1913 	drm_dbg_dp(ctrl->drm_dev, "phy=%p init=%d power_on=%d\n",
1914 			phy, phy->init_count, phy->power_count);
1915 	return ret;
1916 }
1917 
1918 int dp_ctrl_off_link(struct dp_ctrl *dp_ctrl)
1919 {
1920 	struct dp_ctrl_private *ctrl;
1921 	struct dp_io *dp_io;
1922 	struct phy *phy;
1923 	int ret;
1924 
1925 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1926 	dp_io = &ctrl->parser->io;
1927 	phy = dp_io->phy;
1928 
1929 	dp_catalog_ctrl_mainlink_ctrl(ctrl->catalog, false);
1930 
1931 	ret = dp_power_clk_enable(ctrl->power, DP_CTRL_PM, false);
1932 	if (ret) {
1933 		DRM_ERROR("Failed to disable link clocks. ret=%d\n", ret);
1934 	}
1935 
1936 	DRM_DEBUG_DP("Before, phy=%p init_count=%d power_on=%d\n",
1937 		phy, phy->init_count, phy->power_count);
1938 
1939 	phy_power_off(phy);
1940 
1941 	DRM_DEBUG_DP("After, phy=%p init_count=%d power_on=%d\n",
1942 		phy, phy->init_count, phy->power_count);
1943 
1944 	return ret;
1945 }
1946 
1947 int dp_ctrl_off(struct dp_ctrl *dp_ctrl)
1948 {
1949 	struct dp_ctrl_private *ctrl;
1950 	struct dp_io *dp_io;
1951 	struct phy *phy;
1952 	int ret = 0;
1953 
1954 	if (!dp_ctrl)
1955 		return -EINVAL;
1956 
1957 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1958 	dp_io = &ctrl->parser->io;
1959 	phy = dp_io->phy;
1960 
1961 	dp_catalog_ctrl_mainlink_ctrl(ctrl->catalog, false);
1962 
1963 	dp_catalog_ctrl_reset(ctrl->catalog);
1964 
1965 	ret = dp_power_clk_enable(ctrl->power, DP_STREAM_PM, false);
1966 	if (ret)
1967 		DRM_ERROR("Failed to disable pixel clocks. ret=%d\n", ret);
1968 
1969 	dev_pm_opp_set_rate(ctrl->dev, 0);
1970 	ret = dp_power_clk_enable(ctrl->power, DP_CTRL_PM, false);
1971 	if (ret) {
1972 		DRM_ERROR("Failed to disable link clocks. ret=%d\n", ret);
1973 	}
1974 
1975 	phy_power_off(phy);
1976 	drm_dbg_dp(ctrl->drm_dev, "phy=%p init=%d power_on=%d\n",
1977 			phy, phy->init_count, phy->power_count);
1978 
1979 	return ret;
1980 }
1981 
1982 void dp_ctrl_isr(struct dp_ctrl *dp_ctrl)
1983 {
1984 	struct dp_ctrl_private *ctrl;
1985 	u32 isr;
1986 
1987 	if (!dp_ctrl)
1988 		return;
1989 
1990 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
1991 
1992 	isr = dp_catalog_ctrl_get_interrupt(ctrl->catalog);
1993 
1994 	if (isr & DP_CTRL_INTR_READY_FOR_VIDEO) {
1995 		drm_dbg_dp(ctrl->drm_dev, "dp_video_ready\n");
1996 		complete(&ctrl->video_comp);
1997 	}
1998 
1999 	if (isr & DP_CTRL_INTR_IDLE_PATTERN_SENT) {
2000 		drm_dbg_dp(ctrl->drm_dev, "idle_patterns_sent\n");
2001 		complete(&ctrl->idle_comp);
2002 	}
2003 }
2004 
2005 struct dp_ctrl *dp_ctrl_get(struct device *dev, struct dp_link *link,
2006 			struct dp_panel *panel,	struct drm_dp_aux *aux,
2007 			struct dp_power *power, struct dp_catalog *catalog,
2008 			struct dp_parser *parser)
2009 {
2010 	struct dp_ctrl_private *ctrl;
2011 	int ret;
2012 
2013 	if (!dev || !panel || !aux ||
2014 	    !link || !catalog) {
2015 		DRM_ERROR("invalid input\n");
2016 		return ERR_PTR(-EINVAL);
2017 	}
2018 
2019 	ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL);
2020 	if (!ctrl) {
2021 		DRM_ERROR("Mem allocation failure\n");
2022 		return ERR_PTR(-ENOMEM);
2023 	}
2024 
2025 	ret = devm_pm_opp_set_clkname(dev, "ctrl_link");
2026 	if (ret) {
2027 		dev_err(dev, "invalid DP OPP table in device tree\n");
2028 		/* caller do PTR_ERR(opp_table) */
2029 		return (struct dp_ctrl *)ERR_PTR(ret);
2030 	}
2031 
2032 	/* OPP table is optional */
2033 	ret = devm_pm_opp_of_add_table(dev);
2034 	if (ret)
2035 		dev_err(dev, "failed to add DP OPP table\n");
2036 
2037 	init_completion(&ctrl->idle_comp);
2038 	init_completion(&ctrl->video_comp);
2039 
2040 	/* in parameters */
2041 	ctrl->parser   = parser;
2042 	ctrl->panel    = panel;
2043 	ctrl->power    = power;
2044 	ctrl->aux      = aux;
2045 	ctrl->link     = link;
2046 	ctrl->catalog  = catalog;
2047 	ctrl->dev      = dev;
2048 
2049 	return &ctrl->dp_ctrl;
2050 }
2051