xref: /linux/drivers/gpu/drm/tegra/dsi.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
1 /*
2  * Copyright (C) 2013 NVIDIA Corporation
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/debugfs.h>
11 #include <linux/host1x.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_platform.h>
15 #include <linux/platform_device.h>
16 #include <linux/reset.h>
17 
18 #include <linux/regulator/consumer.h>
19 
20 #include <drm/drm_atomic_helper.h>
21 #include <drm/drm_mipi_dsi.h>
22 #include <drm/drm_panel.h>
23 
24 #include <video/mipi_display.h>
25 
26 #include "dc.h"
27 #include "drm.h"
28 #include "dsi.h"
29 #include "mipi-phy.h"
30 
31 struct tegra_dsi_state {
32 	struct drm_connector_state base;
33 
34 	struct mipi_dphy_timing timing;
35 	unsigned long period;
36 
37 	unsigned int vrefresh;
38 	unsigned int lanes;
39 	unsigned long pclk;
40 	unsigned long bclk;
41 
42 	enum tegra_dsi_format format;
43 	unsigned int mul;
44 	unsigned int div;
45 };
46 
47 static inline struct tegra_dsi_state *
48 to_dsi_state(struct drm_connector_state *state)
49 {
50 	return container_of(state, struct tegra_dsi_state, base);
51 }
52 
53 struct tegra_dsi {
54 	struct host1x_client client;
55 	struct tegra_output output;
56 	struct device *dev;
57 
58 	void __iomem *regs;
59 
60 	struct reset_control *rst;
61 	struct clk *clk_parent;
62 	struct clk *clk_lp;
63 	struct clk *clk;
64 
65 	struct drm_info_list *debugfs_files;
66 	struct drm_minor *minor;
67 	struct dentry *debugfs;
68 
69 	unsigned long flags;
70 	enum mipi_dsi_pixel_format format;
71 	unsigned int lanes;
72 
73 	struct tegra_mipi_device *mipi;
74 	struct mipi_dsi_host host;
75 
76 	struct regulator *vdd;
77 
78 	unsigned int video_fifo_depth;
79 	unsigned int host_fifo_depth;
80 
81 	/* for ganged-mode support */
82 	struct tegra_dsi *master;
83 	struct tegra_dsi *slave;
84 };
85 
86 static inline struct tegra_dsi *
87 host1x_client_to_dsi(struct host1x_client *client)
88 {
89 	return container_of(client, struct tegra_dsi, client);
90 }
91 
92 static inline struct tegra_dsi *host_to_tegra(struct mipi_dsi_host *host)
93 {
94 	return container_of(host, struct tegra_dsi, host);
95 }
96 
97 static inline struct tegra_dsi *to_dsi(struct tegra_output *output)
98 {
99 	return container_of(output, struct tegra_dsi, output);
100 }
101 
102 static struct tegra_dsi_state *tegra_dsi_get_state(struct tegra_dsi *dsi)
103 {
104 	return to_dsi_state(dsi->output.connector.state);
105 }
106 
107 static inline u32 tegra_dsi_readl(struct tegra_dsi *dsi, unsigned long reg)
108 {
109 	return readl(dsi->regs + (reg << 2));
110 }
111 
112 static inline void tegra_dsi_writel(struct tegra_dsi *dsi, u32 value,
113 				    unsigned long reg)
114 {
115 	writel(value, dsi->regs + (reg << 2));
116 }
117 
118 static int tegra_dsi_show_regs(struct seq_file *s, void *data)
119 {
120 	struct drm_info_node *node = s->private;
121 	struct tegra_dsi *dsi = node->info_ent->data;
122 
123 #define DUMP_REG(name)						\
124 	seq_printf(s, "%-32s %#05x %08x\n", #name, name,	\
125 		   tegra_dsi_readl(dsi, name))
126 
127 	DUMP_REG(DSI_INCR_SYNCPT);
128 	DUMP_REG(DSI_INCR_SYNCPT_CONTROL);
129 	DUMP_REG(DSI_INCR_SYNCPT_ERROR);
130 	DUMP_REG(DSI_CTXSW);
131 	DUMP_REG(DSI_RD_DATA);
132 	DUMP_REG(DSI_WR_DATA);
133 	DUMP_REG(DSI_POWER_CONTROL);
134 	DUMP_REG(DSI_INT_ENABLE);
135 	DUMP_REG(DSI_INT_STATUS);
136 	DUMP_REG(DSI_INT_MASK);
137 	DUMP_REG(DSI_HOST_CONTROL);
138 	DUMP_REG(DSI_CONTROL);
139 	DUMP_REG(DSI_SOL_DELAY);
140 	DUMP_REG(DSI_MAX_THRESHOLD);
141 	DUMP_REG(DSI_TRIGGER);
142 	DUMP_REG(DSI_TX_CRC);
143 	DUMP_REG(DSI_STATUS);
144 
145 	DUMP_REG(DSI_INIT_SEQ_CONTROL);
146 	DUMP_REG(DSI_INIT_SEQ_DATA_0);
147 	DUMP_REG(DSI_INIT_SEQ_DATA_1);
148 	DUMP_REG(DSI_INIT_SEQ_DATA_2);
149 	DUMP_REG(DSI_INIT_SEQ_DATA_3);
150 	DUMP_REG(DSI_INIT_SEQ_DATA_4);
151 	DUMP_REG(DSI_INIT_SEQ_DATA_5);
152 	DUMP_REG(DSI_INIT_SEQ_DATA_6);
153 	DUMP_REG(DSI_INIT_SEQ_DATA_7);
154 
155 	DUMP_REG(DSI_PKT_SEQ_0_LO);
156 	DUMP_REG(DSI_PKT_SEQ_0_HI);
157 	DUMP_REG(DSI_PKT_SEQ_1_LO);
158 	DUMP_REG(DSI_PKT_SEQ_1_HI);
159 	DUMP_REG(DSI_PKT_SEQ_2_LO);
160 	DUMP_REG(DSI_PKT_SEQ_2_HI);
161 	DUMP_REG(DSI_PKT_SEQ_3_LO);
162 	DUMP_REG(DSI_PKT_SEQ_3_HI);
163 	DUMP_REG(DSI_PKT_SEQ_4_LO);
164 	DUMP_REG(DSI_PKT_SEQ_4_HI);
165 	DUMP_REG(DSI_PKT_SEQ_5_LO);
166 	DUMP_REG(DSI_PKT_SEQ_5_HI);
167 
168 	DUMP_REG(DSI_DCS_CMDS);
169 
170 	DUMP_REG(DSI_PKT_LEN_0_1);
171 	DUMP_REG(DSI_PKT_LEN_2_3);
172 	DUMP_REG(DSI_PKT_LEN_4_5);
173 	DUMP_REG(DSI_PKT_LEN_6_7);
174 
175 	DUMP_REG(DSI_PHY_TIMING_0);
176 	DUMP_REG(DSI_PHY_TIMING_1);
177 	DUMP_REG(DSI_PHY_TIMING_2);
178 	DUMP_REG(DSI_BTA_TIMING);
179 
180 	DUMP_REG(DSI_TIMEOUT_0);
181 	DUMP_REG(DSI_TIMEOUT_1);
182 	DUMP_REG(DSI_TO_TALLY);
183 
184 	DUMP_REG(DSI_PAD_CONTROL_0);
185 	DUMP_REG(DSI_PAD_CONTROL_CD);
186 	DUMP_REG(DSI_PAD_CD_STATUS);
187 	DUMP_REG(DSI_VIDEO_MODE_CONTROL);
188 	DUMP_REG(DSI_PAD_CONTROL_1);
189 	DUMP_REG(DSI_PAD_CONTROL_2);
190 	DUMP_REG(DSI_PAD_CONTROL_3);
191 	DUMP_REG(DSI_PAD_CONTROL_4);
192 
193 	DUMP_REG(DSI_GANGED_MODE_CONTROL);
194 	DUMP_REG(DSI_GANGED_MODE_START);
195 	DUMP_REG(DSI_GANGED_MODE_SIZE);
196 
197 	DUMP_REG(DSI_RAW_DATA_BYTE_COUNT);
198 	DUMP_REG(DSI_ULTRA_LOW_POWER_CONTROL);
199 
200 	DUMP_REG(DSI_INIT_SEQ_DATA_8);
201 	DUMP_REG(DSI_INIT_SEQ_DATA_9);
202 	DUMP_REG(DSI_INIT_SEQ_DATA_10);
203 	DUMP_REG(DSI_INIT_SEQ_DATA_11);
204 	DUMP_REG(DSI_INIT_SEQ_DATA_12);
205 	DUMP_REG(DSI_INIT_SEQ_DATA_13);
206 	DUMP_REG(DSI_INIT_SEQ_DATA_14);
207 	DUMP_REG(DSI_INIT_SEQ_DATA_15);
208 
209 #undef DUMP_REG
210 
211 	return 0;
212 }
213 
214 static struct drm_info_list debugfs_files[] = {
215 	{ "regs", tegra_dsi_show_regs, 0, NULL },
216 };
217 
218 static int tegra_dsi_debugfs_init(struct tegra_dsi *dsi,
219 				  struct drm_minor *minor)
220 {
221 	const char *name = dev_name(dsi->dev);
222 	unsigned int i;
223 	int err;
224 
225 	dsi->debugfs = debugfs_create_dir(name, minor->debugfs_root);
226 	if (!dsi->debugfs)
227 		return -ENOMEM;
228 
229 	dsi->debugfs_files = kmemdup(debugfs_files, sizeof(debugfs_files),
230 				     GFP_KERNEL);
231 	if (!dsi->debugfs_files) {
232 		err = -ENOMEM;
233 		goto remove;
234 	}
235 
236 	for (i = 0; i < ARRAY_SIZE(debugfs_files); i++)
237 		dsi->debugfs_files[i].data = dsi;
238 
239 	err = drm_debugfs_create_files(dsi->debugfs_files,
240 				       ARRAY_SIZE(debugfs_files),
241 				       dsi->debugfs, minor);
242 	if (err < 0)
243 		goto free;
244 
245 	dsi->minor = minor;
246 
247 	return 0;
248 
249 free:
250 	kfree(dsi->debugfs_files);
251 	dsi->debugfs_files = NULL;
252 remove:
253 	debugfs_remove(dsi->debugfs);
254 	dsi->debugfs = NULL;
255 
256 	return err;
257 }
258 
259 static void tegra_dsi_debugfs_exit(struct tegra_dsi *dsi)
260 {
261 	drm_debugfs_remove_files(dsi->debugfs_files, ARRAY_SIZE(debugfs_files),
262 				 dsi->minor);
263 	dsi->minor = NULL;
264 
265 	kfree(dsi->debugfs_files);
266 	dsi->debugfs_files = NULL;
267 
268 	debugfs_remove(dsi->debugfs);
269 	dsi->debugfs = NULL;
270 }
271 
272 #define PKT_ID0(id)	((((id) & 0x3f) <<  3) | (1 <<  9))
273 #define PKT_LEN0(len)	(((len) & 0x07) <<  0)
274 #define PKT_ID1(id)	((((id) & 0x3f) << 13) | (1 << 19))
275 #define PKT_LEN1(len)	(((len) & 0x07) << 10)
276 #define PKT_ID2(id)	((((id) & 0x3f) << 23) | (1 << 29))
277 #define PKT_LEN2(len)	(((len) & 0x07) << 20)
278 
279 #define PKT_LP		(1 << 30)
280 #define NUM_PKT_SEQ	12
281 
282 /*
283  * non-burst mode with sync pulses
284  */
285 static const u32 pkt_seq_video_non_burst_sync_pulses[NUM_PKT_SEQ] = {
286 	[ 0] = PKT_ID0(MIPI_DSI_V_SYNC_START) | PKT_LEN0(0) |
287 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
288 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
289 	       PKT_LP,
290 	[ 1] = 0,
291 	[ 2] = PKT_ID0(MIPI_DSI_V_SYNC_END) | PKT_LEN0(0) |
292 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
293 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
294 	       PKT_LP,
295 	[ 3] = 0,
296 	[ 4] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
297 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
298 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
299 	       PKT_LP,
300 	[ 5] = 0,
301 	[ 6] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
302 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
303 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0),
304 	[ 7] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(2) |
305 	       PKT_ID1(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN1(3) |
306 	       PKT_ID2(MIPI_DSI_BLANKING_PACKET) | PKT_LEN2(4),
307 	[ 8] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
308 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
309 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
310 	       PKT_LP,
311 	[ 9] = 0,
312 	[10] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
313 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
314 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0),
315 	[11] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(2) |
316 	       PKT_ID1(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN1(3) |
317 	       PKT_ID2(MIPI_DSI_BLANKING_PACKET) | PKT_LEN2(4),
318 };
319 
320 /*
321  * non-burst mode with sync events
322  */
323 static const u32 pkt_seq_video_non_burst_sync_events[NUM_PKT_SEQ] = {
324 	[ 0] = PKT_ID0(MIPI_DSI_V_SYNC_START) | PKT_LEN0(0) |
325 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
326 	       PKT_LP,
327 	[ 1] = 0,
328 	[ 2] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
329 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
330 	       PKT_LP,
331 	[ 3] = 0,
332 	[ 4] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
333 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
334 	       PKT_LP,
335 	[ 5] = 0,
336 	[ 6] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
337 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(2) |
338 	       PKT_ID2(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN2(3),
339 	[ 7] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(4),
340 	[ 8] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
341 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
342 	       PKT_LP,
343 	[ 9] = 0,
344 	[10] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
345 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(2) |
346 	       PKT_ID2(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN2(3),
347 	[11] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(4),
348 };
349 
350 static const u32 pkt_seq_command_mode[NUM_PKT_SEQ] = {
351 	[ 0] = 0,
352 	[ 1] = 0,
353 	[ 2] = 0,
354 	[ 3] = 0,
355 	[ 4] = 0,
356 	[ 5] = 0,
357 	[ 6] = PKT_ID0(MIPI_DSI_DCS_LONG_WRITE) | PKT_LEN0(3) | PKT_LP,
358 	[ 7] = 0,
359 	[ 8] = 0,
360 	[ 9] = 0,
361 	[10] = PKT_ID0(MIPI_DSI_DCS_LONG_WRITE) | PKT_LEN0(5) | PKT_LP,
362 	[11] = 0,
363 };
364 
365 static void tegra_dsi_set_phy_timing(struct tegra_dsi *dsi,
366 				     unsigned long period,
367 				     const struct mipi_dphy_timing *timing)
368 {
369 	u32 value;
370 
371 	value = DSI_TIMING_FIELD(timing->hsexit, period, 1) << 24 |
372 		DSI_TIMING_FIELD(timing->hstrail, period, 0) << 16 |
373 		DSI_TIMING_FIELD(timing->hszero, period, 3) << 8 |
374 		DSI_TIMING_FIELD(timing->hsprepare, period, 1);
375 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_0);
376 
377 	value = DSI_TIMING_FIELD(timing->clktrail, period, 1) << 24 |
378 		DSI_TIMING_FIELD(timing->clkpost, period, 1) << 16 |
379 		DSI_TIMING_FIELD(timing->clkzero, period, 1) << 8 |
380 		DSI_TIMING_FIELD(timing->lpx, period, 1);
381 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_1);
382 
383 	value = DSI_TIMING_FIELD(timing->clkprepare, period, 1) << 16 |
384 		DSI_TIMING_FIELD(timing->clkpre, period, 1) << 8 |
385 		DSI_TIMING_FIELD(0xff * period, period, 0) << 0;
386 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_2);
387 
388 	value = DSI_TIMING_FIELD(timing->taget, period, 1) << 16 |
389 		DSI_TIMING_FIELD(timing->tasure, period, 1) << 8 |
390 		DSI_TIMING_FIELD(timing->tago, period, 1);
391 	tegra_dsi_writel(dsi, value, DSI_BTA_TIMING);
392 
393 	if (dsi->slave)
394 		tegra_dsi_set_phy_timing(dsi->slave, period, timing);
395 }
396 
397 static int tegra_dsi_get_muldiv(enum mipi_dsi_pixel_format format,
398 				unsigned int *mulp, unsigned int *divp)
399 {
400 	switch (format) {
401 	case MIPI_DSI_FMT_RGB666_PACKED:
402 	case MIPI_DSI_FMT_RGB888:
403 		*mulp = 3;
404 		*divp = 1;
405 		break;
406 
407 	case MIPI_DSI_FMT_RGB565:
408 		*mulp = 2;
409 		*divp = 1;
410 		break;
411 
412 	case MIPI_DSI_FMT_RGB666:
413 		*mulp = 9;
414 		*divp = 4;
415 		break;
416 
417 	default:
418 		return -EINVAL;
419 	}
420 
421 	return 0;
422 }
423 
424 static int tegra_dsi_get_format(enum mipi_dsi_pixel_format format,
425 				enum tegra_dsi_format *fmt)
426 {
427 	switch (format) {
428 	case MIPI_DSI_FMT_RGB888:
429 		*fmt = TEGRA_DSI_FORMAT_24P;
430 		break;
431 
432 	case MIPI_DSI_FMT_RGB666:
433 		*fmt = TEGRA_DSI_FORMAT_18NP;
434 		break;
435 
436 	case MIPI_DSI_FMT_RGB666_PACKED:
437 		*fmt = TEGRA_DSI_FORMAT_18P;
438 		break;
439 
440 	case MIPI_DSI_FMT_RGB565:
441 		*fmt = TEGRA_DSI_FORMAT_16P;
442 		break;
443 
444 	default:
445 		return -EINVAL;
446 	}
447 
448 	return 0;
449 }
450 
451 static void tegra_dsi_ganged_enable(struct tegra_dsi *dsi, unsigned int start,
452 				    unsigned int size)
453 {
454 	u32 value;
455 
456 	tegra_dsi_writel(dsi, start, DSI_GANGED_MODE_START);
457 	tegra_dsi_writel(dsi, size << 16 | size, DSI_GANGED_MODE_SIZE);
458 
459 	value = DSI_GANGED_MODE_CONTROL_ENABLE;
460 	tegra_dsi_writel(dsi, value, DSI_GANGED_MODE_CONTROL);
461 }
462 
463 static void tegra_dsi_enable(struct tegra_dsi *dsi)
464 {
465 	u32 value;
466 
467 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
468 	value |= DSI_POWER_CONTROL_ENABLE;
469 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
470 
471 	if (dsi->slave)
472 		tegra_dsi_enable(dsi->slave);
473 }
474 
475 static unsigned int tegra_dsi_get_lanes(struct tegra_dsi *dsi)
476 {
477 	if (dsi->master)
478 		return dsi->master->lanes + dsi->lanes;
479 
480 	if (dsi->slave)
481 		return dsi->lanes + dsi->slave->lanes;
482 
483 	return dsi->lanes;
484 }
485 
486 static void tegra_dsi_configure(struct tegra_dsi *dsi, unsigned int pipe,
487 				const struct drm_display_mode *mode)
488 {
489 	unsigned int hact, hsw, hbp, hfp, i, mul, div;
490 	struct tegra_dsi_state *state;
491 	const u32 *pkt_seq;
492 	u32 value;
493 
494 	/* XXX: pass in state into this function? */
495 	if (dsi->master)
496 		state = tegra_dsi_get_state(dsi->master);
497 	else
498 		state = tegra_dsi_get_state(dsi);
499 
500 	mul = state->mul;
501 	div = state->div;
502 
503 	if (dsi->flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
504 		DRM_DEBUG_KMS("Non-burst video mode with sync pulses\n");
505 		pkt_seq = pkt_seq_video_non_burst_sync_pulses;
506 	} else if (dsi->flags & MIPI_DSI_MODE_VIDEO) {
507 		DRM_DEBUG_KMS("Non-burst video mode with sync events\n");
508 		pkt_seq = pkt_seq_video_non_burst_sync_events;
509 	} else {
510 		DRM_DEBUG_KMS("Command mode\n");
511 		pkt_seq = pkt_seq_command_mode;
512 	}
513 
514 	value = DSI_CONTROL_CHANNEL(0) |
515 		DSI_CONTROL_FORMAT(state->format) |
516 		DSI_CONTROL_LANES(dsi->lanes - 1) |
517 		DSI_CONTROL_SOURCE(pipe);
518 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
519 
520 	tegra_dsi_writel(dsi, dsi->video_fifo_depth, DSI_MAX_THRESHOLD);
521 
522 	value = DSI_HOST_CONTROL_HS;
523 	tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
524 
525 	value = tegra_dsi_readl(dsi, DSI_CONTROL);
526 
527 	if (dsi->flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)
528 		value |= DSI_CONTROL_HS_CLK_CTRL;
529 
530 	value &= ~DSI_CONTROL_TX_TRIG(3);
531 
532 	/* enable DCS commands for command mode */
533 	if (dsi->flags & MIPI_DSI_MODE_VIDEO)
534 		value &= ~DSI_CONTROL_DCS_ENABLE;
535 	else
536 		value |= DSI_CONTROL_DCS_ENABLE;
537 
538 	value |= DSI_CONTROL_VIDEO_ENABLE;
539 	value &= ~DSI_CONTROL_HOST_ENABLE;
540 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
541 
542 	for (i = 0; i < NUM_PKT_SEQ; i++)
543 		tegra_dsi_writel(dsi, pkt_seq[i], DSI_PKT_SEQ_0_LO + i);
544 
545 	if (dsi->flags & MIPI_DSI_MODE_VIDEO) {
546 		/* horizontal active pixels */
547 		hact = mode->hdisplay * mul / div;
548 
549 		/* horizontal sync width */
550 		hsw = (mode->hsync_end - mode->hsync_start) * mul / div;
551 		hsw -= 10;
552 
553 		/* horizontal back porch */
554 		hbp = (mode->htotal - mode->hsync_end) * mul / div;
555 		hbp -= 14;
556 
557 		/* horizontal front porch */
558 		hfp = (mode->hsync_start - mode->hdisplay) * mul / div;
559 		hfp -= 8;
560 
561 		tegra_dsi_writel(dsi, hsw << 16 | 0, DSI_PKT_LEN_0_1);
562 		tegra_dsi_writel(dsi, hact << 16 | hbp, DSI_PKT_LEN_2_3);
563 		tegra_dsi_writel(dsi, hfp, DSI_PKT_LEN_4_5);
564 		tegra_dsi_writel(dsi, 0x0f0f << 16, DSI_PKT_LEN_6_7);
565 
566 		/* set SOL delay (for non-burst mode only) */
567 		tegra_dsi_writel(dsi, 8 * mul / div, DSI_SOL_DELAY);
568 
569 		/* TODO: implement ganged mode */
570 	} else {
571 		u16 bytes;
572 
573 		if (dsi->master || dsi->slave) {
574 			/*
575 			 * For ganged mode, assume symmetric left-right mode.
576 			 */
577 			bytes = 1 + (mode->hdisplay / 2) * mul / div;
578 		} else {
579 			/* 1 byte (DCS command) + pixel data */
580 			bytes = 1 + mode->hdisplay * mul / div;
581 		}
582 
583 		tegra_dsi_writel(dsi, 0, DSI_PKT_LEN_0_1);
584 		tegra_dsi_writel(dsi, bytes << 16, DSI_PKT_LEN_2_3);
585 		tegra_dsi_writel(dsi, bytes << 16, DSI_PKT_LEN_4_5);
586 		tegra_dsi_writel(dsi, 0, DSI_PKT_LEN_6_7);
587 
588 		value = MIPI_DCS_WRITE_MEMORY_START << 8 |
589 			MIPI_DCS_WRITE_MEMORY_CONTINUE;
590 		tegra_dsi_writel(dsi, value, DSI_DCS_CMDS);
591 
592 		/* set SOL delay */
593 		if (dsi->master || dsi->slave) {
594 			unsigned long delay, bclk, bclk_ganged;
595 			unsigned int lanes = state->lanes;
596 
597 			/* SOL to valid, valid to FIFO and FIFO write delay */
598 			delay = 4 + 4 + 2;
599 			delay = DIV_ROUND_UP(delay * mul, div * lanes);
600 			/* FIFO read delay */
601 			delay = delay + 6;
602 
603 			bclk = DIV_ROUND_UP(mode->htotal * mul, div * lanes);
604 			bclk_ganged = DIV_ROUND_UP(bclk * lanes / 2, lanes);
605 			value = bclk - bclk_ganged + delay + 20;
606 		} else {
607 			/* TODO: revisit for non-ganged mode */
608 			value = 8 * mul / div;
609 		}
610 
611 		tegra_dsi_writel(dsi, value, DSI_SOL_DELAY);
612 	}
613 
614 	if (dsi->slave) {
615 		tegra_dsi_configure(dsi->slave, pipe, mode);
616 
617 		/*
618 		 * TODO: Support modes other than symmetrical left-right
619 		 * split.
620 		 */
621 		tegra_dsi_ganged_enable(dsi, 0, mode->hdisplay / 2);
622 		tegra_dsi_ganged_enable(dsi->slave, mode->hdisplay / 2,
623 					mode->hdisplay / 2);
624 	}
625 }
626 
627 static int tegra_dsi_wait_idle(struct tegra_dsi *dsi, unsigned long timeout)
628 {
629 	u32 value;
630 
631 	timeout = jiffies + msecs_to_jiffies(timeout);
632 
633 	while (time_before(jiffies, timeout)) {
634 		value = tegra_dsi_readl(dsi, DSI_STATUS);
635 		if (value & DSI_STATUS_IDLE)
636 			return 0;
637 
638 		usleep_range(1000, 2000);
639 	}
640 
641 	return -ETIMEDOUT;
642 }
643 
644 static void tegra_dsi_video_disable(struct tegra_dsi *dsi)
645 {
646 	u32 value;
647 
648 	value = tegra_dsi_readl(dsi, DSI_CONTROL);
649 	value &= ~DSI_CONTROL_VIDEO_ENABLE;
650 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
651 
652 	if (dsi->slave)
653 		tegra_dsi_video_disable(dsi->slave);
654 }
655 
656 static void tegra_dsi_ganged_disable(struct tegra_dsi *dsi)
657 {
658 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_START);
659 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_SIZE);
660 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_CONTROL);
661 }
662 
663 static void tegra_dsi_set_timeout(struct tegra_dsi *dsi, unsigned long bclk,
664 				  unsigned int vrefresh)
665 {
666 	unsigned int timeout;
667 	u32 value;
668 
669 	/* one frame high-speed transmission timeout */
670 	timeout = (bclk / vrefresh) / 512;
671 	value = DSI_TIMEOUT_LRX(0x2000) | DSI_TIMEOUT_HTX(timeout);
672 	tegra_dsi_writel(dsi, value, DSI_TIMEOUT_0);
673 
674 	/* 2 ms peripheral timeout for panel */
675 	timeout = 2 * bclk / 512 * 1000;
676 	value = DSI_TIMEOUT_PR(timeout) | DSI_TIMEOUT_TA(0x2000);
677 	tegra_dsi_writel(dsi, value, DSI_TIMEOUT_1);
678 
679 	value = DSI_TALLY_TA(0) | DSI_TALLY_LRX(0) | DSI_TALLY_HTX(0);
680 	tegra_dsi_writel(dsi, value, DSI_TO_TALLY);
681 
682 	if (dsi->slave)
683 		tegra_dsi_set_timeout(dsi->slave, bclk, vrefresh);
684 }
685 
686 static void tegra_dsi_disable(struct tegra_dsi *dsi)
687 {
688 	u32 value;
689 
690 	if (dsi->slave) {
691 		tegra_dsi_ganged_disable(dsi->slave);
692 		tegra_dsi_ganged_disable(dsi);
693 	}
694 
695 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
696 	value &= ~DSI_POWER_CONTROL_ENABLE;
697 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
698 
699 	if (dsi->slave)
700 		tegra_dsi_disable(dsi->slave);
701 
702 	usleep_range(5000, 10000);
703 }
704 
705 static void tegra_dsi_soft_reset(struct tegra_dsi *dsi)
706 {
707 	u32 value;
708 
709 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
710 	value &= ~DSI_POWER_CONTROL_ENABLE;
711 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
712 
713 	usleep_range(300, 1000);
714 
715 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
716 	value |= DSI_POWER_CONTROL_ENABLE;
717 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
718 
719 	usleep_range(300, 1000);
720 
721 	value = tegra_dsi_readl(dsi, DSI_TRIGGER);
722 	if (value)
723 		tegra_dsi_writel(dsi, 0, DSI_TRIGGER);
724 
725 	if (dsi->slave)
726 		tegra_dsi_soft_reset(dsi->slave);
727 }
728 
729 static void tegra_dsi_connector_dpms(struct drm_connector *connector, int mode)
730 {
731 }
732 
733 static void tegra_dsi_connector_reset(struct drm_connector *connector)
734 {
735 	struct tegra_dsi_state *state;
736 
737 	kfree(connector->state);
738 	connector->state = NULL;
739 
740 	state = kzalloc(sizeof(*state), GFP_KERNEL);
741 	if (state)
742 		connector->state = &state->base;
743 }
744 
745 static struct drm_connector_state *
746 tegra_dsi_connector_duplicate_state(struct drm_connector *connector)
747 {
748 	struct tegra_dsi_state *state = to_dsi_state(connector->state);
749 	struct tegra_dsi_state *copy;
750 
751 	copy = kmemdup(state, sizeof(*state), GFP_KERNEL);
752 	if (!copy)
753 		return NULL;
754 
755 	return &copy->base;
756 }
757 
758 static const struct drm_connector_funcs tegra_dsi_connector_funcs = {
759 	.dpms = tegra_dsi_connector_dpms,
760 	.reset = tegra_dsi_connector_reset,
761 	.detect = tegra_output_connector_detect,
762 	.fill_modes = drm_helper_probe_single_connector_modes,
763 	.destroy = tegra_output_connector_destroy,
764 	.atomic_duplicate_state = tegra_dsi_connector_duplicate_state,
765 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
766 };
767 
768 static enum drm_mode_status
769 tegra_dsi_connector_mode_valid(struct drm_connector *connector,
770 			       struct drm_display_mode *mode)
771 {
772 	return MODE_OK;
773 }
774 
775 static const struct drm_connector_helper_funcs tegra_dsi_connector_helper_funcs = {
776 	.get_modes = tegra_output_connector_get_modes,
777 	.mode_valid = tegra_dsi_connector_mode_valid,
778 	.best_encoder = tegra_output_connector_best_encoder,
779 };
780 
781 static const struct drm_encoder_funcs tegra_dsi_encoder_funcs = {
782 	.destroy = tegra_output_encoder_destroy,
783 };
784 
785 static void tegra_dsi_encoder_dpms(struct drm_encoder *encoder, int mode)
786 {
787 }
788 
789 static void tegra_dsi_encoder_prepare(struct drm_encoder *encoder)
790 {
791 }
792 
793 static void tegra_dsi_encoder_commit(struct drm_encoder *encoder)
794 {
795 }
796 
797 static void tegra_dsi_encoder_mode_set(struct drm_encoder *encoder,
798 				       struct drm_display_mode *mode,
799 				       struct drm_display_mode *adjusted)
800 {
801 	struct tegra_output *output = encoder_to_output(encoder);
802 	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
803 	struct tegra_dsi *dsi = to_dsi(output);
804 	struct tegra_dsi_state *state;
805 	u32 value;
806 
807 	state = tegra_dsi_get_state(dsi);
808 
809 	tegra_dsi_set_timeout(dsi, state->bclk, state->vrefresh);
810 
811 	/*
812 	 * The D-PHY timing fields are expressed in byte-clock cycles, so
813 	 * multiply the period by 8.
814 	 */
815 	tegra_dsi_set_phy_timing(dsi, state->period * 8, &state->timing);
816 
817 	if (output->panel)
818 		drm_panel_prepare(output->panel);
819 
820 	tegra_dsi_configure(dsi, dc->pipe, mode);
821 
822 	/* enable display controller */
823 	value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
824 	value |= DSI_ENABLE;
825 	tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
826 
827 	tegra_dc_commit(dc);
828 
829 	/* enable DSI controller */
830 	tegra_dsi_enable(dsi);
831 
832 	if (output->panel)
833 		drm_panel_enable(output->panel);
834 
835 	return;
836 }
837 
838 static void tegra_dsi_encoder_disable(struct drm_encoder *encoder)
839 {
840 	struct tegra_output *output = encoder_to_output(encoder);
841 	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
842 	struct tegra_dsi *dsi = to_dsi(output);
843 	u32 value;
844 	int err;
845 
846 	if (output->panel)
847 		drm_panel_disable(output->panel);
848 
849 	tegra_dsi_video_disable(dsi);
850 
851 	/*
852 	 * The following accesses registers of the display controller, so make
853 	 * sure it's only executed when the output is attached to one.
854 	 */
855 	if (dc) {
856 		value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
857 		value &= ~DSI_ENABLE;
858 		tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
859 
860 		tegra_dc_commit(dc);
861 	}
862 
863 	err = tegra_dsi_wait_idle(dsi, 100);
864 	if (err < 0)
865 		dev_dbg(dsi->dev, "failed to idle DSI: %d\n", err);
866 
867 	tegra_dsi_soft_reset(dsi);
868 
869 	if (output->panel)
870 		drm_panel_unprepare(output->panel);
871 
872 	tegra_dsi_disable(dsi);
873 
874 	return;
875 }
876 
877 static int
878 tegra_dsi_encoder_atomic_check(struct drm_encoder *encoder,
879 			       struct drm_crtc_state *crtc_state,
880 			       struct drm_connector_state *conn_state)
881 {
882 	struct tegra_output *output = encoder_to_output(encoder);
883 	struct tegra_dsi_state *state = to_dsi_state(conn_state);
884 	struct tegra_dc *dc = to_tegra_dc(conn_state->crtc);
885 	struct tegra_dsi *dsi = to_dsi(output);
886 	unsigned int scdiv;
887 	unsigned long plld;
888 	int err;
889 
890 	state->pclk = crtc_state->mode.clock * 1000;
891 
892 	err = tegra_dsi_get_muldiv(dsi->format, &state->mul, &state->div);
893 	if (err < 0)
894 		return err;
895 
896 	state->lanes = tegra_dsi_get_lanes(dsi);
897 
898 	err = tegra_dsi_get_format(dsi->format, &state->format);
899 	if (err < 0)
900 		return err;
901 
902 	state->vrefresh = drm_mode_vrefresh(&crtc_state->mode);
903 
904 	/* compute byte clock */
905 	state->bclk = (state->pclk * state->mul) / (state->div * state->lanes);
906 
907 	DRM_DEBUG_KMS("mul: %u, div: %u, lanes: %u\n", state->mul, state->div,
908 		      state->lanes);
909 	DRM_DEBUG_KMS("format: %u, vrefresh: %u\n", state->format,
910 		      state->vrefresh);
911 	DRM_DEBUG_KMS("bclk: %lu\n", state->bclk);
912 
913 	/*
914 	 * Compute bit clock and round up to the next MHz.
915 	 */
916 	plld = DIV_ROUND_UP(state->bclk * 8, USEC_PER_SEC) * USEC_PER_SEC;
917 	state->period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, plld);
918 
919 	err = mipi_dphy_timing_get_default(&state->timing, state->period);
920 	if (err < 0)
921 		return err;
922 
923 	err = mipi_dphy_timing_validate(&state->timing, state->period);
924 	if (err < 0) {
925 		dev_err(dsi->dev, "failed to validate D-PHY timing: %d\n", err);
926 		return err;
927 	}
928 
929 	/*
930 	 * We divide the frequency by two here, but we make up for that by
931 	 * setting the shift clock divider (further below) to half of the
932 	 * correct value.
933 	 */
934 	plld /= 2;
935 
936 	/*
937 	 * Derive pixel clock from bit clock using the shift clock divider.
938 	 * Note that this is only half of what we would expect, but we need
939 	 * that to make up for the fact that we divided the bit clock by a
940 	 * factor of two above.
941 	 *
942 	 * It's not clear exactly why this is necessary, but the display is
943 	 * not working properly otherwise. Perhaps the PLLs cannot generate
944 	 * frequencies sufficiently high.
945 	 */
946 	scdiv = ((8 * state->mul) / (state->div * state->lanes)) - 2;
947 
948 	err = tegra_dc_state_setup_clock(dc, crtc_state, dsi->clk_parent,
949 					 plld, scdiv);
950 	if (err < 0) {
951 		dev_err(output->dev, "failed to setup CRTC state: %d\n", err);
952 		return err;
953 	}
954 
955 	return err;
956 }
957 
958 static const struct drm_encoder_helper_funcs tegra_dsi_encoder_helper_funcs = {
959 	.dpms = tegra_dsi_encoder_dpms,
960 	.prepare = tegra_dsi_encoder_prepare,
961 	.commit = tegra_dsi_encoder_commit,
962 	.mode_set = tegra_dsi_encoder_mode_set,
963 	.disable = tegra_dsi_encoder_disable,
964 	.atomic_check = tegra_dsi_encoder_atomic_check,
965 };
966 
967 static int tegra_dsi_pad_enable(struct tegra_dsi *dsi)
968 {
969 	u32 value;
970 
971 	value = DSI_PAD_CONTROL_VS1_PULLDN(0) | DSI_PAD_CONTROL_VS1_PDIO(0);
972 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_0);
973 
974 	return 0;
975 }
976 
977 static int tegra_dsi_pad_calibrate(struct tegra_dsi *dsi)
978 {
979 	u32 value;
980 
981 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_0);
982 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_1);
983 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_2);
984 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_3);
985 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_4);
986 
987 	/* start calibration */
988 	tegra_dsi_pad_enable(dsi);
989 
990 	value = DSI_PAD_SLEW_UP(0x7) | DSI_PAD_SLEW_DN(0x7) |
991 		DSI_PAD_LP_UP(0x1) | DSI_PAD_LP_DN(0x1) |
992 		DSI_PAD_OUT_CLK(0x0);
993 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_2);
994 
995 	return tegra_mipi_calibrate(dsi->mipi);
996 }
997 
998 static int tegra_dsi_init(struct host1x_client *client)
999 {
1000 	struct drm_device *drm = dev_get_drvdata(client->parent);
1001 	struct tegra_dsi *dsi = host1x_client_to_dsi(client);
1002 	int err;
1003 
1004 	reset_control_deassert(dsi->rst);
1005 
1006 	err = tegra_dsi_pad_calibrate(dsi);
1007 	if (err < 0) {
1008 		dev_err(dsi->dev, "MIPI calibration failed: %d\n", err);
1009 		goto reset;
1010 	}
1011 
1012 	/* Gangsters must not register their own outputs. */
1013 	if (!dsi->master) {
1014 		dsi->output.dev = client->dev;
1015 
1016 		drm_connector_init(drm, &dsi->output.connector,
1017 				   &tegra_dsi_connector_funcs,
1018 				   DRM_MODE_CONNECTOR_DSI);
1019 		drm_connector_helper_add(&dsi->output.connector,
1020 					 &tegra_dsi_connector_helper_funcs);
1021 		dsi->output.connector.dpms = DRM_MODE_DPMS_OFF;
1022 
1023 		drm_encoder_init(drm, &dsi->output.encoder,
1024 				 &tegra_dsi_encoder_funcs,
1025 				 DRM_MODE_ENCODER_DSI);
1026 		drm_encoder_helper_add(&dsi->output.encoder,
1027 				       &tegra_dsi_encoder_helper_funcs);
1028 
1029 		drm_mode_connector_attach_encoder(&dsi->output.connector,
1030 						  &dsi->output.encoder);
1031 		drm_connector_register(&dsi->output.connector);
1032 
1033 		err = tegra_output_init(drm, &dsi->output);
1034 		if (err < 0) {
1035 			dev_err(client->dev,
1036 				"failed to initialize output: %d\n",
1037 				err);
1038 			goto reset;
1039 		}
1040 
1041 		dsi->output.encoder.possible_crtcs = 0x3;
1042 	}
1043 
1044 	if (IS_ENABLED(CONFIG_DEBUG_FS)) {
1045 		err = tegra_dsi_debugfs_init(dsi, drm->primary);
1046 		if (err < 0)
1047 			dev_err(dsi->dev, "debugfs setup failed: %d\n", err);
1048 	}
1049 
1050 	return 0;
1051 
1052 reset:
1053 	reset_control_assert(dsi->rst);
1054 	return err;
1055 }
1056 
1057 static int tegra_dsi_exit(struct host1x_client *client)
1058 {
1059 	struct tegra_dsi *dsi = host1x_client_to_dsi(client);
1060 
1061 	tegra_output_exit(&dsi->output);
1062 
1063 	if (IS_ENABLED(CONFIG_DEBUG_FS))
1064 		tegra_dsi_debugfs_exit(dsi);
1065 
1066 	reset_control_assert(dsi->rst);
1067 
1068 	return 0;
1069 }
1070 
1071 static const struct host1x_client_ops dsi_client_ops = {
1072 	.init = tegra_dsi_init,
1073 	.exit = tegra_dsi_exit,
1074 };
1075 
1076 static int tegra_dsi_setup_clocks(struct tegra_dsi *dsi)
1077 {
1078 	struct clk *parent;
1079 	int err;
1080 
1081 	parent = clk_get_parent(dsi->clk);
1082 	if (!parent)
1083 		return -EINVAL;
1084 
1085 	err = clk_set_parent(parent, dsi->clk_parent);
1086 	if (err < 0)
1087 		return err;
1088 
1089 	return 0;
1090 }
1091 
1092 static const char * const error_report[16] = {
1093 	"SoT Error",
1094 	"SoT Sync Error",
1095 	"EoT Sync Error",
1096 	"Escape Mode Entry Command Error",
1097 	"Low-Power Transmit Sync Error",
1098 	"Peripheral Timeout Error",
1099 	"False Control Error",
1100 	"Contention Detected",
1101 	"ECC Error, single-bit",
1102 	"ECC Error, multi-bit",
1103 	"Checksum Error",
1104 	"DSI Data Type Not Recognized",
1105 	"DSI VC ID Invalid",
1106 	"Invalid Transmission Length",
1107 	"Reserved",
1108 	"DSI Protocol Violation",
1109 };
1110 
1111 static ssize_t tegra_dsi_read_response(struct tegra_dsi *dsi,
1112 				       const struct mipi_dsi_msg *msg,
1113 				       size_t count)
1114 {
1115 	u8 *rx = msg->rx_buf;
1116 	unsigned int i, j, k;
1117 	size_t size = 0;
1118 	u16 errors;
1119 	u32 value;
1120 
1121 	/* read and parse packet header */
1122 	value = tegra_dsi_readl(dsi, DSI_RD_DATA);
1123 
1124 	switch (value & 0x3f) {
1125 	case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
1126 		errors = (value >> 8) & 0xffff;
1127 		dev_dbg(dsi->dev, "Acknowledge and error report: %04x\n",
1128 			errors);
1129 		for (i = 0; i < ARRAY_SIZE(error_report); i++)
1130 			if (errors & BIT(i))
1131 				dev_dbg(dsi->dev, "  %2u: %s\n", i,
1132 					error_report[i]);
1133 		break;
1134 
1135 	case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
1136 		rx[0] = (value >> 8) & 0xff;
1137 		size = 1;
1138 		break;
1139 
1140 	case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
1141 		rx[0] = (value >>  8) & 0xff;
1142 		rx[1] = (value >> 16) & 0xff;
1143 		size = 2;
1144 		break;
1145 
1146 	case MIPI_DSI_RX_DCS_LONG_READ_RESPONSE:
1147 		size = ((value >> 8) & 0xff00) | ((value >> 8) & 0xff);
1148 		break;
1149 
1150 	case MIPI_DSI_RX_GENERIC_LONG_READ_RESPONSE:
1151 		size = ((value >> 8) & 0xff00) | ((value >> 8) & 0xff);
1152 		break;
1153 
1154 	default:
1155 		dev_err(dsi->dev, "unhandled response type: %02x\n",
1156 			value & 0x3f);
1157 		return -EPROTO;
1158 	}
1159 
1160 	size = min(size, msg->rx_len);
1161 
1162 	if (msg->rx_buf && size > 0) {
1163 		for (i = 0, j = 0; i < count - 1; i++, j += 4) {
1164 			u8 *rx = msg->rx_buf + j;
1165 
1166 			value = tegra_dsi_readl(dsi, DSI_RD_DATA);
1167 
1168 			for (k = 0; k < 4 && (j + k) < msg->rx_len; k++)
1169 				rx[j + k] = (value >> (k << 3)) & 0xff;
1170 		}
1171 	}
1172 
1173 	return size;
1174 }
1175 
1176 static int tegra_dsi_transmit(struct tegra_dsi *dsi, unsigned long timeout)
1177 {
1178 	tegra_dsi_writel(dsi, DSI_TRIGGER_HOST, DSI_TRIGGER);
1179 
1180 	timeout = jiffies + msecs_to_jiffies(timeout);
1181 
1182 	while (time_before(jiffies, timeout)) {
1183 		u32 value = tegra_dsi_readl(dsi, DSI_TRIGGER);
1184 		if ((value & DSI_TRIGGER_HOST) == 0)
1185 			return 0;
1186 
1187 		usleep_range(1000, 2000);
1188 	}
1189 
1190 	DRM_DEBUG_KMS("timeout waiting for transmission to complete\n");
1191 	return -ETIMEDOUT;
1192 }
1193 
1194 static int tegra_dsi_wait_for_response(struct tegra_dsi *dsi,
1195 				       unsigned long timeout)
1196 {
1197 	timeout = jiffies + msecs_to_jiffies(250);
1198 
1199 	while (time_before(jiffies, timeout)) {
1200 		u32 value = tegra_dsi_readl(dsi, DSI_STATUS);
1201 		u8 count = value & 0x1f;
1202 
1203 		if (count > 0)
1204 			return count;
1205 
1206 		usleep_range(1000, 2000);
1207 	}
1208 
1209 	DRM_DEBUG_KMS("peripheral returned no data\n");
1210 	return -ETIMEDOUT;
1211 }
1212 
1213 static void tegra_dsi_writesl(struct tegra_dsi *dsi, unsigned long offset,
1214 			      const void *buffer, size_t size)
1215 {
1216 	const u8 *buf = buffer;
1217 	size_t i, j;
1218 	u32 value;
1219 
1220 	for (j = 0; j < size; j += 4) {
1221 		value = 0;
1222 
1223 		for (i = 0; i < 4 && j + i < size; i++)
1224 			value |= buf[j + i] << (i << 3);
1225 
1226 		tegra_dsi_writel(dsi, value, DSI_WR_DATA);
1227 	}
1228 }
1229 
1230 static ssize_t tegra_dsi_host_transfer(struct mipi_dsi_host *host,
1231 				       const struct mipi_dsi_msg *msg)
1232 {
1233 	struct tegra_dsi *dsi = host_to_tegra(host);
1234 	struct mipi_dsi_packet packet;
1235 	const u8 *header;
1236 	size_t count;
1237 	ssize_t err;
1238 	u32 value;
1239 
1240 	err = mipi_dsi_create_packet(&packet, msg);
1241 	if (err < 0)
1242 		return err;
1243 
1244 	header = packet.header;
1245 
1246 	/* maximum FIFO depth is 1920 words */
1247 	if (packet.size > dsi->video_fifo_depth * 4)
1248 		return -ENOSPC;
1249 
1250 	/* reset underflow/overflow flags */
1251 	value = tegra_dsi_readl(dsi, DSI_STATUS);
1252 	if (value & (DSI_STATUS_UNDERFLOW | DSI_STATUS_OVERFLOW)) {
1253 		value = DSI_HOST_CONTROL_FIFO_RESET;
1254 		tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
1255 		usleep_range(10, 20);
1256 	}
1257 
1258 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
1259 	value |= DSI_POWER_CONTROL_ENABLE;
1260 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
1261 
1262 	usleep_range(5000, 10000);
1263 
1264 	value = DSI_HOST_CONTROL_CRC_RESET | DSI_HOST_CONTROL_TX_TRIG_HOST |
1265 		DSI_HOST_CONTROL_CS | DSI_HOST_CONTROL_ECC;
1266 
1267 	if ((msg->flags & MIPI_DSI_MSG_USE_LPM) == 0)
1268 		value |= DSI_HOST_CONTROL_HS;
1269 
1270 	/*
1271 	 * The host FIFO has a maximum of 64 words, so larger transmissions
1272 	 * need to use the video FIFO.
1273 	 */
1274 	if (packet.size > dsi->host_fifo_depth * 4)
1275 		value |= DSI_HOST_CONTROL_FIFO_SEL;
1276 
1277 	tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
1278 
1279 	/*
1280 	 * For reads and messages with explicitly requested ACK, generate a
1281 	 * BTA sequence after the transmission of the packet.
1282 	 */
1283 	if ((msg->flags & MIPI_DSI_MSG_REQ_ACK) ||
1284 	    (msg->rx_buf && msg->rx_len > 0)) {
1285 		value = tegra_dsi_readl(dsi, DSI_HOST_CONTROL);
1286 		value |= DSI_HOST_CONTROL_PKT_BTA;
1287 		tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
1288 	}
1289 
1290 	value = DSI_CONTROL_LANES(0) | DSI_CONTROL_HOST_ENABLE;
1291 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
1292 
1293 	/* write packet header, ECC is generated by hardware */
1294 	value = header[2] << 16 | header[1] << 8 | header[0];
1295 	tegra_dsi_writel(dsi, value, DSI_WR_DATA);
1296 
1297 	/* write payload (if any) */
1298 	if (packet.payload_length > 0)
1299 		tegra_dsi_writesl(dsi, DSI_WR_DATA, packet.payload,
1300 				  packet.payload_length);
1301 
1302 	err = tegra_dsi_transmit(dsi, 250);
1303 	if (err < 0)
1304 		return err;
1305 
1306 	if ((msg->flags & MIPI_DSI_MSG_REQ_ACK) ||
1307 	    (msg->rx_buf && msg->rx_len > 0)) {
1308 		err = tegra_dsi_wait_for_response(dsi, 250);
1309 		if (err < 0)
1310 			return err;
1311 
1312 		count = err;
1313 
1314 		value = tegra_dsi_readl(dsi, DSI_RD_DATA);
1315 		switch (value) {
1316 		case 0x84:
1317 			/*
1318 			dev_dbg(dsi->dev, "ACK\n");
1319 			*/
1320 			break;
1321 
1322 		case 0x87:
1323 			/*
1324 			dev_dbg(dsi->dev, "ESCAPE\n");
1325 			*/
1326 			break;
1327 
1328 		default:
1329 			dev_err(dsi->dev, "unknown status: %08x\n", value);
1330 			break;
1331 		}
1332 
1333 		if (count > 1) {
1334 			err = tegra_dsi_read_response(dsi, msg, count);
1335 			if (err < 0)
1336 				dev_err(dsi->dev,
1337 					"failed to parse response: %zd\n",
1338 					err);
1339 			else {
1340 				/*
1341 				 * For read commands, return the number of
1342 				 * bytes returned by the peripheral.
1343 				 */
1344 				count = err;
1345 			}
1346 		}
1347 	} else {
1348 		/*
1349 		 * For write commands, we have transmitted the 4-byte header
1350 		 * plus the variable-length payload.
1351 		 */
1352 		count = 4 + packet.payload_length;
1353 	}
1354 
1355 	return count;
1356 }
1357 
1358 static int tegra_dsi_ganged_setup(struct tegra_dsi *dsi)
1359 {
1360 	struct clk *parent;
1361 	int err;
1362 
1363 	/* make sure both DSI controllers share the same PLL */
1364 	parent = clk_get_parent(dsi->slave->clk);
1365 	if (!parent)
1366 		return -EINVAL;
1367 
1368 	err = clk_set_parent(parent, dsi->clk_parent);
1369 	if (err < 0)
1370 		return err;
1371 
1372 	return 0;
1373 }
1374 
1375 static int tegra_dsi_host_attach(struct mipi_dsi_host *host,
1376 				 struct mipi_dsi_device *device)
1377 {
1378 	struct tegra_dsi *dsi = host_to_tegra(host);
1379 
1380 	dsi->flags = device->mode_flags;
1381 	dsi->format = device->format;
1382 	dsi->lanes = device->lanes;
1383 
1384 	if (dsi->slave) {
1385 		int err;
1386 
1387 		dev_dbg(dsi->dev, "attaching dual-channel device %s\n",
1388 			dev_name(&device->dev));
1389 
1390 		err = tegra_dsi_ganged_setup(dsi);
1391 		if (err < 0) {
1392 			dev_err(dsi->dev, "failed to set up ganged mode: %d\n",
1393 				err);
1394 			return err;
1395 		}
1396 	}
1397 
1398 	/*
1399 	 * Slaves don't have a panel associated with them, so they provide
1400 	 * merely the second channel.
1401 	 */
1402 	if (!dsi->master) {
1403 		struct tegra_output *output = &dsi->output;
1404 
1405 		output->panel = of_drm_find_panel(device->dev.of_node);
1406 		if (output->panel && output->connector.dev) {
1407 			drm_panel_attach(output->panel, &output->connector);
1408 			drm_helper_hpd_irq_event(output->connector.dev);
1409 		}
1410 	}
1411 
1412 	return 0;
1413 }
1414 
1415 static int tegra_dsi_host_detach(struct mipi_dsi_host *host,
1416 				 struct mipi_dsi_device *device)
1417 {
1418 	struct tegra_dsi *dsi = host_to_tegra(host);
1419 	struct tegra_output *output = &dsi->output;
1420 
1421 	if (output->panel && &device->dev == output->panel->dev) {
1422 		output->panel = NULL;
1423 
1424 		if (output->connector.dev)
1425 			drm_helper_hpd_irq_event(output->connector.dev);
1426 	}
1427 
1428 	return 0;
1429 }
1430 
1431 static const struct mipi_dsi_host_ops tegra_dsi_host_ops = {
1432 	.attach = tegra_dsi_host_attach,
1433 	.detach = tegra_dsi_host_detach,
1434 	.transfer = tegra_dsi_host_transfer,
1435 };
1436 
1437 static int tegra_dsi_ganged_probe(struct tegra_dsi *dsi)
1438 {
1439 	struct device_node *np;
1440 
1441 	np = of_parse_phandle(dsi->dev->of_node, "nvidia,ganged-mode", 0);
1442 	if (np) {
1443 		struct platform_device *gangster = of_find_device_by_node(np);
1444 
1445 		dsi->slave = platform_get_drvdata(gangster);
1446 		of_node_put(np);
1447 
1448 		if (!dsi->slave)
1449 			return -EPROBE_DEFER;
1450 
1451 		dsi->slave->master = dsi;
1452 	}
1453 
1454 	return 0;
1455 }
1456 
1457 static int tegra_dsi_probe(struct platform_device *pdev)
1458 {
1459 	struct tegra_dsi *dsi;
1460 	struct resource *regs;
1461 	int err;
1462 
1463 	dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
1464 	if (!dsi)
1465 		return -ENOMEM;
1466 
1467 	dsi->output.dev = dsi->dev = &pdev->dev;
1468 	dsi->video_fifo_depth = 1920;
1469 	dsi->host_fifo_depth = 64;
1470 
1471 	err = tegra_dsi_ganged_probe(dsi);
1472 	if (err < 0)
1473 		return err;
1474 
1475 	err = tegra_output_probe(&dsi->output);
1476 	if (err < 0)
1477 		return err;
1478 
1479 	dsi->output.connector.polled = DRM_CONNECTOR_POLL_HPD;
1480 
1481 	/*
1482 	 * Assume these values by default. When a DSI peripheral driver
1483 	 * attaches to the DSI host, the parameters will be taken from
1484 	 * the attached device.
1485 	 */
1486 	dsi->flags = MIPI_DSI_MODE_VIDEO;
1487 	dsi->format = MIPI_DSI_FMT_RGB888;
1488 	dsi->lanes = 4;
1489 
1490 	dsi->rst = devm_reset_control_get(&pdev->dev, "dsi");
1491 	if (IS_ERR(dsi->rst))
1492 		return PTR_ERR(dsi->rst);
1493 
1494 	dsi->clk = devm_clk_get(&pdev->dev, NULL);
1495 	if (IS_ERR(dsi->clk)) {
1496 		dev_err(&pdev->dev, "cannot get DSI clock\n");
1497 		err = PTR_ERR(dsi->clk);
1498 		goto reset;
1499 	}
1500 
1501 	err = clk_prepare_enable(dsi->clk);
1502 	if (err < 0) {
1503 		dev_err(&pdev->dev, "cannot enable DSI clock\n");
1504 		goto reset;
1505 	}
1506 
1507 	dsi->clk_lp = devm_clk_get(&pdev->dev, "lp");
1508 	if (IS_ERR(dsi->clk_lp)) {
1509 		dev_err(&pdev->dev, "cannot get low-power clock\n");
1510 		err = PTR_ERR(dsi->clk_lp);
1511 		goto disable_clk;
1512 	}
1513 
1514 	err = clk_prepare_enable(dsi->clk_lp);
1515 	if (err < 0) {
1516 		dev_err(&pdev->dev, "cannot enable low-power clock\n");
1517 		goto disable_clk;
1518 	}
1519 
1520 	dsi->clk_parent = devm_clk_get(&pdev->dev, "parent");
1521 	if (IS_ERR(dsi->clk_parent)) {
1522 		dev_err(&pdev->dev, "cannot get parent clock\n");
1523 		err = PTR_ERR(dsi->clk_parent);
1524 		goto disable_clk_lp;
1525 	}
1526 
1527 	dsi->vdd = devm_regulator_get(&pdev->dev, "avdd-dsi-csi");
1528 	if (IS_ERR(dsi->vdd)) {
1529 		dev_err(&pdev->dev, "cannot get VDD supply\n");
1530 		err = PTR_ERR(dsi->vdd);
1531 		goto disable_clk_lp;
1532 	}
1533 
1534 	err = regulator_enable(dsi->vdd);
1535 	if (err < 0) {
1536 		dev_err(&pdev->dev, "cannot enable VDD supply\n");
1537 		goto disable_clk_lp;
1538 	}
1539 
1540 	err = tegra_dsi_setup_clocks(dsi);
1541 	if (err < 0) {
1542 		dev_err(&pdev->dev, "cannot setup clocks\n");
1543 		goto disable_vdd;
1544 	}
1545 
1546 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1547 	dsi->regs = devm_ioremap_resource(&pdev->dev, regs);
1548 	if (IS_ERR(dsi->regs)) {
1549 		err = PTR_ERR(dsi->regs);
1550 		goto disable_vdd;
1551 	}
1552 
1553 	dsi->mipi = tegra_mipi_request(&pdev->dev);
1554 	if (IS_ERR(dsi->mipi)) {
1555 		err = PTR_ERR(dsi->mipi);
1556 		goto disable_vdd;
1557 	}
1558 
1559 	dsi->host.ops = &tegra_dsi_host_ops;
1560 	dsi->host.dev = &pdev->dev;
1561 
1562 	err = mipi_dsi_host_register(&dsi->host);
1563 	if (err < 0) {
1564 		dev_err(&pdev->dev, "failed to register DSI host: %d\n", err);
1565 		goto mipi_free;
1566 	}
1567 
1568 	INIT_LIST_HEAD(&dsi->client.list);
1569 	dsi->client.ops = &dsi_client_ops;
1570 	dsi->client.dev = &pdev->dev;
1571 
1572 	err = host1x_client_register(&dsi->client);
1573 	if (err < 0) {
1574 		dev_err(&pdev->dev, "failed to register host1x client: %d\n",
1575 			err);
1576 		goto unregister;
1577 	}
1578 
1579 	platform_set_drvdata(pdev, dsi);
1580 
1581 	return 0;
1582 
1583 unregister:
1584 	mipi_dsi_host_unregister(&dsi->host);
1585 mipi_free:
1586 	tegra_mipi_free(dsi->mipi);
1587 disable_vdd:
1588 	regulator_disable(dsi->vdd);
1589 disable_clk_lp:
1590 	clk_disable_unprepare(dsi->clk_lp);
1591 disable_clk:
1592 	clk_disable_unprepare(dsi->clk);
1593 reset:
1594 	reset_control_assert(dsi->rst);
1595 	return err;
1596 }
1597 
1598 static int tegra_dsi_remove(struct platform_device *pdev)
1599 {
1600 	struct tegra_dsi *dsi = platform_get_drvdata(pdev);
1601 	int err;
1602 
1603 	err = host1x_client_unregister(&dsi->client);
1604 	if (err < 0) {
1605 		dev_err(&pdev->dev, "failed to unregister host1x client: %d\n",
1606 			err);
1607 		return err;
1608 	}
1609 
1610 	tegra_output_remove(&dsi->output);
1611 
1612 	mipi_dsi_host_unregister(&dsi->host);
1613 	tegra_mipi_free(dsi->mipi);
1614 
1615 	regulator_disable(dsi->vdd);
1616 	clk_disable_unprepare(dsi->clk_lp);
1617 	clk_disable_unprepare(dsi->clk);
1618 	reset_control_assert(dsi->rst);
1619 
1620 	return 0;
1621 }
1622 
1623 static const struct of_device_id tegra_dsi_of_match[] = {
1624 	{ .compatible = "nvidia,tegra114-dsi", },
1625 	{ },
1626 };
1627 MODULE_DEVICE_TABLE(of, tegra_dsi_of_match);
1628 
1629 struct platform_driver tegra_dsi_driver = {
1630 	.driver = {
1631 		.name = "tegra-dsi",
1632 		.of_match_table = tegra_dsi_of_match,
1633 	},
1634 	.probe = tegra_dsi_probe,
1635 	.remove = tegra_dsi_remove,
1636 };
1637