xref: /openbmc/linux/drivers/gpu/drm/tegra/dsi.c (revision ca55b2fe)
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 	struct drm_crtc *crtc = dsi->output.encoder.crtc;
123 	struct drm_device *drm = node->minor->dev;
124 	int err = 0;
125 
126 	drm_modeset_lock_all(drm);
127 
128 	if (!crtc || !crtc->state->active) {
129 		err = -EBUSY;
130 		goto unlock;
131 	}
132 
133 #define DUMP_REG(name)						\
134 	seq_printf(s, "%-32s %#05x %08x\n", #name, name,	\
135 		   tegra_dsi_readl(dsi, name))
136 
137 	DUMP_REG(DSI_INCR_SYNCPT);
138 	DUMP_REG(DSI_INCR_SYNCPT_CONTROL);
139 	DUMP_REG(DSI_INCR_SYNCPT_ERROR);
140 	DUMP_REG(DSI_CTXSW);
141 	DUMP_REG(DSI_RD_DATA);
142 	DUMP_REG(DSI_WR_DATA);
143 	DUMP_REG(DSI_POWER_CONTROL);
144 	DUMP_REG(DSI_INT_ENABLE);
145 	DUMP_REG(DSI_INT_STATUS);
146 	DUMP_REG(DSI_INT_MASK);
147 	DUMP_REG(DSI_HOST_CONTROL);
148 	DUMP_REG(DSI_CONTROL);
149 	DUMP_REG(DSI_SOL_DELAY);
150 	DUMP_REG(DSI_MAX_THRESHOLD);
151 	DUMP_REG(DSI_TRIGGER);
152 	DUMP_REG(DSI_TX_CRC);
153 	DUMP_REG(DSI_STATUS);
154 
155 	DUMP_REG(DSI_INIT_SEQ_CONTROL);
156 	DUMP_REG(DSI_INIT_SEQ_DATA_0);
157 	DUMP_REG(DSI_INIT_SEQ_DATA_1);
158 	DUMP_REG(DSI_INIT_SEQ_DATA_2);
159 	DUMP_REG(DSI_INIT_SEQ_DATA_3);
160 	DUMP_REG(DSI_INIT_SEQ_DATA_4);
161 	DUMP_REG(DSI_INIT_SEQ_DATA_5);
162 	DUMP_REG(DSI_INIT_SEQ_DATA_6);
163 	DUMP_REG(DSI_INIT_SEQ_DATA_7);
164 
165 	DUMP_REG(DSI_PKT_SEQ_0_LO);
166 	DUMP_REG(DSI_PKT_SEQ_0_HI);
167 	DUMP_REG(DSI_PKT_SEQ_1_LO);
168 	DUMP_REG(DSI_PKT_SEQ_1_HI);
169 	DUMP_REG(DSI_PKT_SEQ_2_LO);
170 	DUMP_REG(DSI_PKT_SEQ_2_HI);
171 	DUMP_REG(DSI_PKT_SEQ_3_LO);
172 	DUMP_REG(DSI_PKT_SEQ_3_HI);
173 	DUMP_REG(DSI_PKT_SEQ_4_LO);
174 	DUMP_REG(DSI_PKT_SEQ_4_HI);
175 	DUMP_REG(DSI_PKT_SEQ_5_LO);
176 	DUMP_REG(DSI_PKT_SEQ_5_HI);
177 
178 	DUMP_REG(DSI_DCS_CMDS);
179 
180 	DUMP_REG(DSI_PKT_LEN_0_1);
181 	DUMP_REG(DSI_PKT_LEN_2_3);
182 	DUMP_REG(DSI_PKT_LEN_4_5);
183 	DUMP_REG(DSI_PKT_LEN_6_7);
184 
185 	DUMP_REG(DSI_PHY_TIMING_0);
186 	DUMP_REG(DSI_PHY_TIMING_1);
187 	DUMP_REG(DSI_PHY_TIMING_2);
188 	DUMP_REG(DSI_BTA_TIMING);
189 
190 	DUMP_REG(DSI_TIMEOUT_0);
191 	DUMP_REG(DSI_TIMEOUT_1);
192 	DUMP_REG(DSI_TO_TALLY);
193 
194 	DUMP_REG(DSI_PAD_CONTROL_0);
195 	DUMP_REG(DSI_PAD_CONTROL_CD);
196 	DUMP_REG(DSI_PAD_CD_STATUS);
197 	DUMP_REG(DSI_VIDEO_MODE_CONTROL);
198 	DUMP_REG(DSI_PAD_CONTROL_1);
199 	DUMP_REG(DSI_PAD_CONTROL_2);
200 	DUMP_REG(DSI_PAD_CONTROL_3);
201 	DUMP_REG(DSI_PAD_CONTROL_4);
202 
203 	DUMP_REG(DSI_GANGED_MODE_CONTROL);
204 	DUMP_REG(DSI_GANGED_MODE_START);
205 	DUMP_REG(DSI_GANGED_MODE_SIZE);
206 
207 	DUMP_REG(DSI_RAW_DATA_BYTE_COUNT);
208 	DUMP_REG(DSI_ULTRA_LOW_POWER_CONTROL);
209 
210 	DUMP_REG(DSI_INIT_SEQ_DATA_8);
211 	DUMP_REG(DSI_INIT_SEQ_DATA_9);
212 	DUMP_REG(DSI_INIT_SEQ_DATA_10);
213 	DUMP_REG(DSI_INIT_SEQ_DATA_11);
214 	DUMP_REG(DSI_INIT_SEQ_DATA_12);
215 	DUMP_REG(DSI_INIT_SEQ_DATA_13);
216 	DUMP_REG(DSI_INIT_SEQ_DATA_14);
217 	DUMP_REG(DSI_INIT_SEQ_DATA_15);
218 
219 #undef DUMP_REG
220 
221 unlock:
222 	drm_modeset_unlock_all(drm);
223 	return err;
224 }
225 
226 static struct drm_info_list debugfs_files[] = {
227 	{ "regs", tegra_dsi_show_regs, 0, NULL },
228 };
229 
230 static int tegra_dsi_debugfs_init(struct tegra_dsi *dsi,
231 				  struct drm_minor *minor)
232 {
233 	const char *name = dev_name(dsi->dev);
234 	unsigned int i;
235 	int err;
236 
237 	dsi->debugfs = debugfs_create_dir(name, minor->debugfs_root);
238 	if (!dsi->debugfs)
239 		return -ENOMEM;
240 
241 	dsi->debugfs_files = kmemdup(debugfs_files, sizeof(debugfs_files),
242 				     GFP_KERNEL);
243 	if (!dsi->debugfs_files) {
244 		err = -ENOMEM;
245 		goto remove;
246 	}
247 
248 	for (i = 0; i < ARRAY_SIZE(debugfs_files); i++)
249 		dsi->debugfs_files[i].data = dsi;
250 
251 	err = drm_debugfs_create_files(dsi->debugfs_files,
252 				       ARRAY_SIZE(debugfs_files),
253 				       dsi->debugfs, minor);
254 	if (err < 0)
255 		goto free;
256 
257 	dsi->minor = minor;
258 
259 	return 0;
260 
261 free:
262 	kfree(dsi->debugfs_files);
263 	dsi->debugfs_files = NULL;
264 remove:
265 	debugfs_remove(dsi->debugfs);
266 	dsi->debugfs = NULL;
267 
268 	return err;
269 }
270 
271 static void tegra_dsi_debugfs_exit(struct tegra_dsi *dsi)
272 {
273 	drm_debugfs_remove_files(dsi->debugfs_files, ARRAY_SIZE(debugfs_files),
274 				 dsi->minor);
275 	dsi->minor = NULL;
276 
277 	kfree(dsi->debugfs_files);
278 	dsi->debugfs_files = NULL;
279 
280 	debugfs_remove(dsi->debugfs);
281 	dsi->debugfs = NULL;
282 }
283 
284 #define PKT_ID0(id)	((((id) & 0x3f) <<  3) | (1 <<  9))
285 #define PKT_LEN0(len)	(((len) & 0x07) <<  0)
286 #define PKT_ID1(id)	((((id) & 0x3f) << 13) | (1 << 19))
287 #define PKT_LEN1(len)	(((len) & 0x07) << 10)
288 #define PKT_ID2(id)	((((id) & 0x3f) << 23) | (1 << 29))
289 #define PKT_LEN2(len)	(((len) & 0x07) << 20)
290 
291 #define PKT_LP		(1 << 30)
292 #define NUM_PKT_SEQ	12
293 
294 /*
295  * non-burst mode with sync pulses
296  */
297 static const u32 pkt_seq_video_non_burst_sync_pulses[NUM_PKT_SEQ] = {
298 	[ 0] = PKT_ID0(MIPI_DSI_V_SYNC_START) | PKT_LEN0(0) |
299 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
300 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
301 	       PKT_LP,
302 	[ 1] = 0,
303 	[ 2] = PKT_ID0(MIPI_DSI_V_SYNC_END) | PKT_LEN0(0) |
304 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
305 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
306 	       PKT_LP,
307 	[ 3] = 0,
308 	[ 4] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
309 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
310 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
311 	       PKT_LP,
312 	[ 5] = 0,
313 	[ 6] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
314 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
315 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0),
316 	[ 7] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(2) |
317 	       PKT_ID1(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN1(3) |
318 	       PKT_ID2(MIPI_DSI_BLANKING_PACKET) | PKT_LEN2(4),
319 	[ 8] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
320 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
321 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
322 	       PKT_LP,
323 	[ 9] = 0,
324 	[10] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
325 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
326 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0),
327 	[11] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(2) |
328 	       PKT_ID1(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN1(3) |
329 	       PKT_ID2(MIPI_DSI_BLANKING_PACKET) | PKT_LEN2(4),
330 };
331 
332 /*
333  * non-burst mode with sync events
334  */
335 static const u32 pkt_seq_video_non_burst_sync_events[NUM_PKT_SEQ] = {
336 	[ 0] = PKT_ID0(MIPI_DSI_V_SYNC_START) | PKT_LEN0(0) |
337 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
338 	       PKT_LP,
339 	[ 1] = 0,
340 	[ 2] = 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 	[ 3] = 0,
344 	[ 4] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
345 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
346 	       PKT_LP,
347 	[ 5] = 0,
348 	[ 6] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
349 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(2) |
350 	       PKT_ID2(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN2(3),
351 	[ 7] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(4),
352 	[ 8] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
353 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
354 	       PKT_LP,
355 	[ 9] = 0,
356 	[10] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
357 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(2) |
358 	       PKT_ID2(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN2(3),
359 	[11] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(4),
360 };
361 
362 static const u32 pkt_seq_command_mode[NUM_PKT_SEQ] = {
363 	[ 0] = 0,
364 	[ 1] = 0,
365 	[ 2] = 0,
366 	[ 3] = 0,
367 	[ 4] = 0,
368 	[ 5] = 0,
369 	[ 6] = PKT_ID0(MIPI_DSI_DCS_LONG_WRITE) | PKT_LEN0(3) | PKT_LP,
370 	[ 7] = 0,
371 	[ 8] = 0,
372 	[ 9] = 0,
373 	[10] = PKT_ID0(MIPI_DSI_DCS_LONG_WRITE) | PKT_LEN0(5) | PKT_LP,
374 	[11] = 0,
375 };
376 
377 static void tegra_dsi_set_phy_timing(struct tegra_dsi *dsi,
378 				     unsigned long period,
379 				     const struct mipi_dphy_timing *timing)
380 {
381 	u32 value;
382 
383 	value = DSI_TIMING_FIELD(timing->hsexit, period, 1) << 24 |
384 		DSI_TIMING_FIELD(timing->hstrail, period, 0) << 16 |
385 		DSI_TIMING_FIELD(timing->hszero, period, 3) << 8 |
386 		DSI_TIMING_FIELD(timing->hsprepare, period, 1);
387 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_0);
388 
389 	value = DSI_TIMING_FIELD(timing->clktrail, period, 1) << 24 |
390 		DSI_TIMING_FIELD(timing->clkpost, period, 1) << 16 |
391 		DSI_TIMING_FIELD(timing->clkzero, period, 1) << 8 |
392 		DSI_TIMING_FIELD(timing->lpx, period, 1);
393 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_1);
394 
395 	value = DSI_TIMING_FIELD(timing->clkprepare, period, 1) << 16 |
396 		DSI_TIMING_FIELD(timing->clkpre, period, 1) << 8 |
397 		DSI_TIMING_FIELD(0xff * period, period, 0) << 0;
398 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_2);
399 
400 	value = DSI_TIMING_FIELD(timing->taget, period, 1) << 16 |
401 		DSI_TIMING_FIELD(timing->tasure, period, 1) << 8 |
402 		DSI_TIMING_FIELD(timing->tago, period, 1);
403 	tegra_dsi_writel(dsi, value, DSI_BTA_TIMING);
404 
405 	if (dsi->slave)
406 		tegra_dsi_set_phy_timing(dsi->slave, period, timing);
407 }
408 
409 static int tegra_dsi_get_muldiv(enum mipi_dsi_pixel_format format,
410 				unsigned int *mulp, unsigned int *divp)
411 {
412 	switch (format) {
413 	case MIPI_DSI_FMT_RGB666_PACKED:
414 	case MIPI_DSI_FMT_RGB888:
415 		*mulp = 3;
416 		*divp = 1;
417 		break;
418 
419 	case MIPI_DSI_FMT_RGB565:
420 		*mulp = 2;
421 		*divp = 1;
422 		break;
423 
424 	case MIPI_DSI_FMT_RGB666:
425 		*mulp = 9;
426 		*divp = 4;
427 		break;
428 
429 	default:
430 		return -EINVAL;
431 	}
432 
433 	return 0;
434 }
435 
436 static int tegra_dsi_get_format(enum mipi_dsi_pixel_format format,
437 				enum tegra_dsi_format *fmt)
438 {
439 	switch (format) {
440 	case MIPI_DSI_FMT_RGB888:
441 		*fmt = TEGRA_DSI_FORMAT_24P;
442 		break;
443 
444 	case MIPI_DSI_FMT_RGB666:
445 		*fmt = TEGRA_DSI_FORMAT_18NP;
446 		break;
447 
448 	case MIPI_DSI_FMT_RGB666_PACKED:
449 		*fmt = TEGRA_DSI_FORMAT_18P;
450 		break;
451 
452 	case MIPI_DSI_FMT_RGB565:
453 		*fmt = TEGRA_DSI_FORMAT_16P;
454 		break;
455 
456 	default:
457 		return -EINVAL;
458 	}
459 
460 	return 0;
461 }
462 
463 static void tegra_dsi_ganged_enable(struct tegra_dsi *dsi, unsigned int start,
464 				    unsigned int size)
465 {
466 	u32 value;
467 
468 	tegra_dsi_writel(dsi, start, DSI_GANGED_MODE_START);
469 	tegra_dsi_writel(dsi, size << 16 | size, DSI_GANGED_MODE_SIZE);
470 
471 	value = DSI_GANGED_MODE_CONTROL_ENABLE;
472 	tegra_dsi_writel(dsi, value, DSI_GANGED_MODE_CONTROL);
473 }
474 
475 static void tegra_dsi_enable(struct tegra_dsi *dsi)
476 {
477 	u32 value;
478 
479 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
480 	value |= DSI_POWER_CONTROL_ENABLE;
481 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
482 
483 	if (dsi->slave)
484 		tegra_dsi_enable(dsi->slave);
485 }
486 
487 static unsigned int tegra_dsi_get_lanes(struct tegra_dsi *dsi)
488 {
489 	if (dsi->master)
490 		return dsi->master->lanes + dsi->lanes;
491 
492 	if (dsi->slave)
493 		return dsi->lanes + dsi->slave->lanes;
494 
495 	return dsi->lanes;
496 }
497 
498 static void tegra_dsi_configure(struct tegra_dsi *dsi, unsigned int pipe,
499 				const struct drm_display_mode *mode)
500 {
501 	unsigned int hact, hsw, hbp, hfp, i, mul, div;
502 	struct tegra_dsi_state *state;
503 	const u32 *pkt_seq;
504 	u32 value;
505 
506 	/* XXX: pass in state into this function? */
507 	if (dsi->master)
508 		state = tegra_dsi_get_state(dsi->master);
509 	else
510 		state = tegra_dsi_get_state(dsi);
511 
512 	mul = state->mul;
513 	div = state->div;
514 
515 	if (dsi->flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
516 		DRM_DEBUG_KMS("Non-burst video mode with sync pulses\n");
517 		pkt_seq = pkt_seq_video_non_burst_sync_pulses;
518 	} else if (dsi->flags & MIPI_DSI_MODE_VIDEO) {
519 		DRM_DEBUG_KMS("Non-burst video mode with sync events\n");
520 		pkt_seq = pkt_seq_video_non_burst_sync_events;
521 	} else {
522 		DRM_DEBUG_KMS("Command mode\n");
523 		pkt_seq = pkt_seq_command_mode;
524 	}
525 
526 	value = DSI_CONTROL_CHANNEL(0) |
527 		DSI_CONTROL_FORMAT(state->format) |
528 		DSI_CONTROL_LANES(dsi->lanes - 1) |
529 		DSI_CONTROL_SOURCE(pipe);
530 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
531 
532 	tegra_dsi_writel(dsi, dsi->video_fifo_depth, DSI_MAX_THRESHOLD);
533 
534 	value = DSI_HOST_CONTROL_HS;
535 	tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
536 
537 	value = tegra_dsi_readl(dsi, DSI_CONTROL);
538 
539 	if (dsi->flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)
540 		value |= DSI_CONTROL_HS_CLK_CTRL;
541 
542 	value &= ~DSI_CONTROL_TX_TRIG(3);
543 
544 	/* enable DCS commands for command mode */
545 	if (dsi->flags & MIPI_DSI_MODE_VIDEO)
546 		value &= ~DSI_CONTROL_DCS_ENABLE;
547 	else
548 		value |= DSI_CONTROL_DCS_ENABLE;
549 
550 	value |= DSI_CONTROL_VIDEO_ENABLE;
551 	value &= ~DSI_CONTROL_HOST_ENABLE;
552 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
553 
554 	for (i = 0; i < NUM_PKT_SEQ; i++)
555 		tegra_dsi_writel(dsi, pkt_seq[i], DSI_PKT_SEQ_0_LO + i);
556 
557 	if (dsi->flags & MIPI_DSI_MODE_VIDEO) {
558 		/* horizontal active pixels */
559 		hact = mode->hdisplay * mul / div;
560 
561 		/* horizontal sync width */
562 		hsw = (mode->hsync_end - mode->hsync_start) * mul / div;
563 
564 		/* horizontal back porch */
565 		hbp = (mode->htotal - mode->hsync_end) * mul / div;
566 
567 		if ((dsi->flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) == 0)
568 			hbp += hsw;
569 
570 		/* horizontal front porch */
571 		hfp = (mode->hsync_start - mode->hdisplay) * mul / div;
572 
573 		/* subtract packet overhead */
574 		hsw -= 10;
575 		hbp -= 14;
576 		hfp -= 8;
577 
578 		tegra_dsi_writel(dsi, hsw << 16 | 0, DSI_PKT_LEN_0_1);
579 		tegra_dsi_writel(dsi, hact << 16 | hbp, DSI_PKT_LEN_2_3);
580 		tegra_dsi_writel(dsi, hfp, DSI_PKT_LEN_4_5);
581 		tegra_dsi_writel(dsi, 0x0f0f << 16, DSI_PKT_LEN_6_7);
582 
583 		/* set SOL delay (for non-burst mode only) */
584 		tegra_dsi_writel(dsi, 8 * mul / div, DSI_SOL_DELAY);
585 
586 		/* TODO: implement ganged mode */
587 	} else {
588 		u16 bytes;
589 
590 		if (dsi->master || dsi->slave) {
591 			/*
592 			 * For ganged mode, assume symmetric left-right mode.
593 			 */
594 			bytes = 1 + (mode->hdisplay / 2) * mul / div;
595 		} else {
596 			/* 1 byte (DCS command) + pixel data */
597 			bytes = 1 + mode->hdisplay * mul / div;
598 		}
599 
600 		tegra_dsi_writel(dsi, 0, DSI_PKT_LEN_0_1);
601 		tegra_dsi_writel(dsi, bytes << 16, DSI_PKT_LEN_2_3);
602 		tegra_dsi_writel(dsi, bytes << 16, DSI_PKT_LEN_4_5);
603 		tegra_dsi_writel(dsi, 0, DSI_PKT_LEN_6_7);
604 
605 		value = MIPI_DCS_WRITE_MEMORY_START << 8 |
606 			MIPI_DCS_WRITE_MEMORY_CONTINUE;
607 		tegra_dsi_writel(dsi, value, DSI_DCS_CMDS);
608 
609 		/* set SOL delay */
610 		if (dsi->master || dsi->slave) {
611 			unsigned long delay, bclk, bclk_ganged;
612 			unsigned int lanes = state->lanes;
613 
614 			/* SOL to valid, valid to FIFO and FIFO write delay */
615 			delay = 4 + 4 + 2;
616 			delay = DIV_ROUND_UP(delay * mul, div * lanes);
617 			/* FIFO read delay */
618 			delay = delay + 6;
619 
620 			bclk = DIV_ROUND_UP(mode->htotal * mul, div * lanes);
621 			bclk_ganged = DIV_ROUND_UP(bclk * lanes / 2, lanes);
622 			value = bclk - bclk_ganged + delay + 20;
623 		} else {
624 			/* TODO: revisit for non-ganged mode */
625 			value = 8 * mul / div;
626 		}
627 
628 		tegra_dsi_writel(dsi, value, DSI_SOL_DELAY);
629 	}
630 
631 	if (dsi->slave) {
632 		tegra_dsi_configure(dsi->slave, pipe, mode);
633 
634 		/*
635 		 * TODO: Support modes other than symmetrical left-right
636 		 * split.
637 		 */
638 		tegra_dsi_ganged_enable(dsi, 0, mode->hdisplay / 2);
639 		tegra_dsi_ganged_enable(dsi->slave, mode->hdisplay / 2,
640 					mode->hdisplay / 2);
641 	}
642 }
643 
644 static int tegra_dsi_wait_idle(struct tegra_dsi *dsi, unsigned long timeout)
645 {
646 	u32 value;
647 
648 	timeout = jiffies + msecs_to_jiffies(timeout);
649 
650 	while (time_before(jiffies, timeout)) {
651 		value = tegra_dsi_readl(dsi, DSI_STATUS);
652 		if (value & DSI_STATUS_IDLE)
653 			return 0;
654 
655 		usleep_range(1000, 2000);
656 	}
657 
658 	return -ETIMEDOUT;
659 }
660 
661 static void tegra_dsi_video_disable(struct tegra_dsi *dsi)
662 {
663 	u32 value;
664 
665 	value = tegra_dsi_readl(dsi, DSI_CONTROL);
666 	value &= ~DSI_CONTROL_VIDEO_ENABLE;
667 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
668 
669 	if (dsi->slave)
670 		tegra_dsi_video_disable(dsi->slave);
671 }
672 
673 static void tegra_dsi_ganged_disable(struct tegra_dsi *dsi)
674 {
675 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_START);
676 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_SIZE);
677 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_CONTROL);
678 }
679 
680 static void tegra_dsi_set_timeout(struct tegra_dsi *dsi, unsigned long bclk,
681 				  unsigned int vrefresh)
682 {
683 	unsigned int timeout;
684 	u32 value;
685 
686 	/* one frame high-speed transmission timeout */
687 	timeout = (bclk / vrefresh) / 512;
688 	value = DSI_TIMEOUT_LRX(0x2000) | DSI_TIMEOUT_HTX(timeout);
689 	tegra_dsi_writel(dsi, value, DSI_TIMEOUT_0);
690 
691 	/* 2 ms peripheral timeout for panel */
692 	timeout = 2 * bclk / 512 * 1000;
693 	value = DSI_TIMEOUT_PR(timeout) | DSI_TIMEOUT_TA(0x2000);
694 	tegra_dsi_writel(dsi, value, DSI_TIMEOUT_1);
695 
696 	value = DSI_TALLY_TA(0) | DSI_TALLY_LRX(0) | DSI_TALLY_HTX(0);
697 	tegra_dsi_writel(dsi, value, DSI_TO_TALLY);
698 
699 	if (dsi->slave)
700 		tegra_dsi_set_timeout(dsi->slave, bclk, vrefresh);
701 }
702 
703 static void tegra_dsi_disable(struct tegra_dsi *dsi)
704 {
705 	u32 value;
706 
707 	if (dsi->slave) {
708 		tegra_dsi_ganged_disable(dsi->slave);
709 		tegra_dsi_ganged_disable(dsi);
710 	}
711 
712 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
713 	value &= ~DSI_POWER_CONTROL_ENABLE;
714 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
715 
716 	if (dsi->slave)
717 		tegra_dsi_disable(dsi->slave);
718 
719 	usleep_range(5000, 10000);
720 }
721 
722 static void tegra_dsi_soft_reset(struct tegra_dsi *dsi)
723 {
724 	u32 value;
725 
726 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
727 	value &= ~DSI_POWER_CONTROL_ENABLE;
728 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
729 
730 	usleep_range(300, 1000);
731 
732 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
733 	value |= DSI_POWER_CONTROL_ENABLE;
734 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
735 
736 	usleep_range(300, 1000);
737 
738 	value = tegra_dsi_readl(dsi, DSI_TRIGGER);
739 	if (value)
740 		tegra_dsi_writel(dsi, 0, DSI_TRIGGER);
741 
742 	if (dsi->slave)
743 		tegra_dsi_soft_reset(dsi->slave);
744 }
745 
746 static void tegra_dsi_connector_reset(struct drm_connector *connector)
747 {
748 	struct tegra_dsi_state *state;
749 
750 	kfree(connector->state);
751 	connector->state = NULL;
752 
753 	state = kzalloc(sizeof(*state), GFP_KERNEL);
754 	if (state)
755 		connector->state = &state->base;
756 }
757 
758 static struct drm_connector_state *
759 tegra_dsi_connector_duplicate_state(struct drm_connector *connector)
760 {
761 	struct tegra_dsi_state *state = to_dsi_state(connector->state);
762 	struct tegra_dsi_state *copy;
763 
764 	copy = kmemdup(state, sizeof(*state), GFP_KERNEL);
765 	if (!copy)
766 		return NULL;
767 
768 	return &copy->base;
769 }
770 
771 static const struct drm_connector_funcs tegra_dsi_connector_funcs = {
772 	.dpms = drm_atomic_helper_connector_dpms,
773 	.reset = tegra_dsi_connector_reset,
774 	.detect = tegra_output_connector_detect,
775 	.fill_modes = drm_helper_probe_single_connector_modes,
776 	.destroy = tegra_output_connector_destroy,
777 	.atomic_duplicate_state = tegra_dsi_connector_duplicate_state,
778 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
779 };
780 
781 static enum drm_mode_status
782 tegra_dsi_connector_mode_valid(struct drm_connector *connector,
783 			       struct drm_display_mode *mode)
784 {
785 	return MODE_OK;
786 }
787 
788 static const struct drm_connector_helper_funcs tegra_dsi_connector_helper_funcs = {
789 	.get_modes = tegra_output_connector_get_modes,
790 	.mode_valid = tegra_dsi_connector_mode_valid,
791 	.best_encoder = tegra_output_connector_best_encoder,
792 };
793 
794 static const struct drm_encoder_funcs tegra_dsi_encoder_funcs = {
795 	.destroy = tegra_output_encoder_destroy,
796 };
797 
798 static void tegra_dsi_encoder_disable(struct drm_encoder *encoder)
799 {
800 	struct tegra_output *output = encoder_to_output(encoder);
801 	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
802 	struct tegra_dsi *dsi = to_dsi(output);
803 	u32 value;
804 	int err;
805 
806 	if (output->panel)
807 		drm_panel_disable(output->panel);
808 
809 	tegra_dsi_video_disable(dsi);
810 
811 	/*
812 	 * The following accesses registers of the display controller, so make
813 	 * sure it's only executed when the output is attached to one.
814 	 */
815 	if (dc) {
816 		value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
817 		value &= ~DSI_ENABLE;
818 		tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
819 
820 		tegra_dc_commit(dc);
821 	}
822 
823 	err = tegra_dsi_wait_idle(dsi, 100);
824 	if (err < 0)
825 		dev_dbg(dsi->dev, "failed to idle DSI: %d\n", err);
826 
827 	tegra_dsi_soft_reset(dsi);
828 
829 	if (output->panel)
830 		drm_panel_unprepare(output->panel);
831 
832 	tegra_dsi_disable(dsi);
833 
834 	return;
835 }
836 
837 static void tegra_dsi_encoder_enable(struct drm_encoder *encoder)
838 {
839 	struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode;
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 	struct tegra_dsi_state *state;
844 	u32 value;
845 
846 	state = tegra_dsi_get_state(dsi);
847 
848 	tegra_dsi_set_timeout(dsi, state->bclk, state->vrefresh);
849 
850 	/*
851 	 * The D-PHY timing fields are expressed in byte-clock cycles, so
852 	 * multiply the period by 8.
853 	 */
854 	tegra_dsi_set_phy_timing(dsi, state->period * 8, &state->timing);
855 
856 	if (output->panel)
857 		drm_panel_prepare(output->panel);
858 
859 	tegra_dsi_configure(dsi, dc->pipe, mode);
860 
861 	/* enable display controller */
862 	value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
863 	value |= DSI_ENABLE;
864 	tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
865 
866 	tegra_dc_commit(dc);
867 
868 	/* enable DSI controller */
869 	tegra_dsi_enable(dsi);
870 
871 	if (output->panel)
872 		drm_panel_enable(output->panel);
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 	.disable = tegra_dsi_encoder_disable,
960 	.enable = tegra_dsi_encoder_enable,
961 	.atomic_check = tegra_dsi_encoder_atomic_check,
962 };
963 
964 static int tegra_dsi_pad_enable(struct tegra_dsi *dsi)
965 {
966 	u32 value;
967 
968 	value = DSI_PAD_CONTROL_VS1_PULLDN(0) | DSI_PAD_CONTROL_VS1_PDIO(0);
969 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_0);
970 
971 	return 0;
972 }
973 
974 static int tegra_dsi_pad_calibrate(struct tegra_dsi *dsi)
975 {
976 	u32 value;
977 
978 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_0);
979 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_1);
980 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_2);
981 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_3);
982 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_4);
983 
984 	/* start calibration */
985 	tegra_dsi_pad_enable(dsi);
986 
987 	value = DSI_PAD_SLEW_UP(0x7) | DSI_PAD_SLEW_DN(0x7) |
988 		DSI_PAD_LP_UP(0x1) | DSI_PAD_LP_DN(0x1) |
989 		DSI_PAD_OUT_CLK(0x0);
990 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_2);
991 
992 	value = DSI_PAD_PREEMP_PD_CLK(0x3) | DSI_PAD_PREEMP_PU_CLK(0x3) |
993 		DSI_PAD_PREEMP_PD(0x03) | DSI_PAD_PREEMP_PU(0x3);
994 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_3);
995 
996 	return tegra_mipi_calibrate(dsi->mipi);
997 }
998 
999 static int tegra_dsi_init(struct host1x_client *client)
1000 {
1001 	struct drm_device *drm = dev_get_drvdata(client->parent);
1002 	struct tegra_dsi *dsi = host1x_client_to_dsi(client);
1003 	int err;
1004 
1005 	reset_control_deassert(dsi->rst);
1006 
1007 	err = tegra_dsi_pad_calibrate(dsi);
1008 	if (err < 0) {
1009 		dev_err(dsi->dev, "MIPI calibration failed: %d\n", err);
1010 		goto reset;
1011 	}
1012 
1013 	/* Gangsters must not register their own outputs. */
1014 	if (!dsi->master) {
1015 		dsi->output.dev = client->dev;
1016 
1017 		drm_connector_init(drm, &dsi->output.connector,
1018 				   &tegra_dsi_connector_funcs,
1019 				   DRM_MODE_CONNECTOR_DSI);
1020 		drm_connector_helper_add(&dsi->output.connector,
1021 					 &tegra_dsi_connector_helper_funcs);
1022 		dsi->output.connector.dpms = DRM_MODE_DPMS_OFF;
1023 
1024 		drm_encoder_init(drm, &dsi->output.encoder,
1025 				 &tegra_dsi_encoder_funcs,
1026 				 DRM_MODE_ENCODER_DSI);
1027 		drm_encoder_helper_add(&dsi->output.encoder,
1028 				       &tegra_dsi_encoder_helper_funcs);
1029 
1030 		drm_mode_connector_attach_encoder(&dsi->output.connector,
1031 						  &dsi->output.encoder);
1032 		drm_connector_register(&dsi->output.connector);
1033 
1034 		err = tegra_output_init(drm, &dsi->output);
1035 		if (err < 0) {
1036 			dev_err(client->dev,
1037 				"failed to initialize output: %d\n",
1038 				err);
1039 			goto reset;
1040 		}
1041 
1042 		dsi->output.encoder.possible_crtcs = 0x3;
1043 	}
1044 
1045 	if (IS_ENABLED(CONFIG_DEBUG_FS)) {
1046 		err = tegra_dsi_debugfs_init(dsi, drm->primary);
1047 		if (err < 0)
1048 			dev_err(dsi->dev, "debugfs setup failed: %d\n", err);
1049 	}
1050 
1051 	return 0;
1052 
1053 reset:
1054 	reset_control_assert(dsi->rst);
1055 	return err;
1056 }
1057 
1058 static int tegra_dsi_exit(struct host1x_client *client)
1059 {
1060 	struct tegra_dsi *dsi = host1x_client_to_dsi(client);
1061 
1062 	tegra_output_exit(&dsi->output);
1063 
1064 	if (IS_ENABLED(CONFIG_DEBUG_FS))
1065 		tegra_dsi_debugfs_exit(dsi);
1066 
1067 	reset_control_assert(dsi->rst);
1068 
1069 	return 0;
1070 }
1071 
1072 static const struct host1x_client_ops dsi_client_ops = {
1073 	.init = tegra_dsi_init,
1074 	.exit = tegra_dsi_exit,
1075 };
1076 
1077 static int tegra_dsi_setup_clocks(struct tegra_dsi *dsi)
1078 {
1079 	struct clk *parent;
1080 	int err;
1081 
1082 	parent = clk_get_parent(dsi->clk);
1083 	if (!parent)
1084 		return -EINVAL;
1085 
1086 	err = clk_set_parent(parent, dsi->clk_parent);
1087 	if (err < 0)
1088 		return err;
1089 
1090 	return 0;
1091 }
1092 
1093 static const char * const error_report[16] = {
1094 	"SoT Error",
1095 	"SoT Sync Error",
1096 	"EoT Sync Error",
1097 	"Escape Mode Entry Command Error",
1098 	"Low-Power Transmit Sync Error",
1099 	"Peripheral Timeout Error",
1100 	"False Control Error",
1101 	"Contention Detected",
1102 	"ECC Error, single-bit",
1103 	"ECC Error, multi-bit",
1104 	"Checksum Error",
1105 	"DSI Data Type Not Recognized",
1106 	"DSI VC ID Invalid",
1107 	"Invalid Transmission Length",
1108 	"Reserved",
1109 	"DSI Protocol Violation",
1110 };
1111 
1112 static ssize_t tegra_dsi_read_response(struct tegra_dsi *dsi,
1113 				       const struct mipi_dsi_msg *msg,
1114 				       size_t count)
1115 {
1116 	u8 *rx = msg->rx_buf;
1117 	unsigned int i, j, k;
1118 	size_t size = 0;
1119 	u16 errors;
1120 	u32 value;
1121 
1122 	/* read and parse packet header */
1123 	value = tegra_dsi_readl(dsi, DSI_RD_DATA);
1124 
1125 	switch (value & 0x3f) {
1126 	case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
1127 		errors = (value >> 8) & 0xffff;
1128 		dev_dbg(dsi->dev, "Acknowledge and error report: %04x\n",
1129 			errors);
1130 		for (i = 0; i < ARRAY_SIZE(error_report); i++)
1131 			if (errors & BIT(i))
1132 				dev_dbg(dsi->dev, "  %2u: %s\n", i,
1133 					error_report[i]);
1134 		break;
1135 
1136 	case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
1137 		rx[0] = (value >> 8) & 0xff;
1138 		size = 1;
1139 		break;
1140 
1141 	case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
1142 		rx[0] = (value >>  8) & 0xff;
1143 		rx[1] = (value >> 16) & 0xff;
1144 		size = 2;
1145 		break;
1146 
1147 	case MIPI_DSI_RX_DCS_LONG_READ_RESPONSE:
1148 		size = ((value >> 8) & 0xff00) | ((value >> 8) & 0xff);
1149 		break;
1150 
1151 	case MIPI_DSI_RX_GENERIC_LONG_READ_RESPONSE:
1152 		size = ((value >> 8) & 0xff00) | ((value >> 8) & 0xff);
1153 		break;
1154 
1155 	default:
1156 		dev_err(dsi->dev, "unhandled response type: %02x\n",
1157 			value & 0x3f);
1158 		return -EPROTO;
1159 	}
1160 
1161 	size = min(size, msg->rx_len);
1162 
1163 	if (msg->rx_buf && size > 0) {
1164 		for (i = 0, j = 0; i < count - 1; i++, j += 4) {
1165 			u8 *rx = msg->rx_buf + j;
1166 
1167 			value = tegra_dsi_readl(dsi, DSI_RD_DATA);
1168 
1169 			for (k = 0; k < 4 && (j + k) < msg->rx_len; k++)
1170 				rx[j + k] = (value >> (k << 3)) & 0xff;
1171 		}
1172 	}
1173 
1174 	return size;
1175 }
1176 
1177 static int tegra_dsi_transmit(struct tegra_dsi *dsi, unsigned long timeout)
1178 {
1179 	tegra_dsi_writel(dsi, DSI_TRIGGER_HOST, DSI_TRIGGER);
1180 
1181 	timeout = jiffies + msecs_to_jiffies(timeout);
1182 
1183 	while (time_before(jiffies, timeout)) {
1184 		u32 value = tegra_dsi_readl(dsi, DSI_TRIGGER);
1185 		if ((value & DSI_TRIGGER_HOST) == 0)
1186 			return 0;
1187 
1188 		usleep_range(1000, 2000);
1189 	}
1190 
1191 	DRM_DEBUG_KMS("timeout waiting for transmission to complete\n");
1192 	return -ETIMEDOUT;
1193 }
1194 
1195 static int tegra_dsi_wait_for_response(struct tegra_dsi *dsi,
1196 				       unsigned long timeout)
1197 {
1198 	timeout = jiffies + msecs_to_jiffies(250);
1199 
1200 	while (time_before(jiffies, timeout)) {
1201 		u32 value = tegra_dsi_readl(dsi, DSI_STATUS);
1202 		u8 count = value & 0x1f;
1203 
1204 		if (count > 0)
1205 			return count;
1206 
1207 		usleep_range(1000, 2000);
1208 	}
1209 
1210 	DRM_DEBUG_KMS("peripheral returned no data\n");
1211 	return -ETIMEDOUT;
1212 }
1213 
1214 static void tegra_dsi_writesl(struct tegra_dsi *dsi, unsigned long offset,
1215 			      const void *buffer, size_t size)
1216 {
1217 	const u8 *buf = buffer;
1218 	size_t i, j;
1219 	u32 value;
1220 
1221 	for (j = 0; j < size; j += 4) {
1222 		value = 0;
1223 
1224 		for (i = 0; i < 4 && j + i < size; i++)
1225 			value |= buf[j + i] << (i << 3);
1226 
1227 		tegra_dsi_writel(dsi, value, DSI_WR_DATA);
1228 	}
1229 }
1230 
1231 static ssize_t tegra_dsi_host_transfer(struct mipi_dsi_host *host,
1232 				       const struct mipi_dsi_msg *msg)
1233 {
1234 	struct tegra_dsi *dsi = host_to_tegra(host);
1235 	struct mipi_dsi_packet packet;
1236 	const u8 *header;
1237 	size_t count;
1238 	ssize_t err;
1239 	u32 value;
1240 
1241 	err = mipi_dsi_create_packet(&packet, msg);
1242 	if (err < 0)
1243 		return err;
1244 
1245 	header = packet.header;
1246 
1247 	/* maximum FIFO depth is 1920 words */
1248 	if (packet.size > dsi->video_fifo_depth * 4)
1249 		return -ENOSPC;
1250 
1251 	/* reset underflow/overflow flags */
1252 	value = tegra_dsi_readl(dsi, DSI_STATUS);
1253 	if (value & (DSI_STATUS_UNDERFLOW | DSI_STATUS_OVERFLOW)) {
1254 		value = DSI_HOST_CONTROL_FIFO_RESET;
1255 		tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
1256 		usleep_range(10, 20);
1257 	}
1258 
1259 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
1260 	value |= DSI_POWER_CONTROL_ENABLE;
1261 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
1262 
1263 	usleep_range(5000, 10000);
1264 
1265 	value = DSI_HOST_CONTROL_CRC_RESET | DSI_HOST_CONTROL_TX_TRIG_HOST |
1266 		DSI_HOST_CONTROL_CS | DSI_HOST_CONTROL_ECC;
1267 
1268 	if ((msg->flags & MIPI_DSI_MSG_USE_LPM) == 0)
1269 		value |= DSI_HOST_CONTROL_HS;
1270 
1271 	/*
1272 	 * The host FIFO has a maximum of 64 words, so larger transmissions
1273 	 * need to use the video FIFO.
1274 	 */
1275 	if (packet.size > dsi->host_fifo_depth * 4)
1276 		value |= DSI_HOST_CONTROL_FIFO_SEL;
1277 
1278 	tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
1279 
1280 	/*
1281 	 * For reads and messages with explicitly requested ACK, generate a
1282 	 * BTA sequence after the transmission of the packet.
1283 	 */
1284 	if ((msg->flags & MIPI_DSI_MSG_REQ_ACK) ||
1285 	    (msg->rx_buf && msg->rx_len > 0)) {
1286 		value = tegra_dsi_readl(dsi, DSI_HOST_CONTROL);
1287 		value |= DSI_HOST_CONTROL_PKT_BTA;
1288 		tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
1289 	}
1290 
1291 	value = DSI_CONTROL_LANES(0) | DSI_CONTROL_HOST_ENABLE;
1292 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
1293 
1294 	/* write packet header, ECC is generated by hardware */
1295 	value = header[2] << 16 | header[1] << 8 | header[0];
1296 	tegra_dsi_writel(dsi, value, DSI_WR_DATA);
1297 
1298 	/* write payload (if any) */
1299 	if (packet.payload_length > 0)
1300 		tegra_dsi_writesl(dsi, DSI_WR_DATA, packet.payload,
1301 				  packet.payload_length);
1302 
1303 	err = tegra_dsi_transmit(dsi, 250);
1304 	if (err < 0)
1305 		return err;
1306 
1307 	if ((msg->flags & MIPI_DSI_MSG_REQ_ACK) ||
1308 	    (msg->rx_buf && msg->rx_len > 0)) {
1309 		err = tegra_dsi_wait_for_response(dsi, 250);
1310 		if (err < 0)
1311 			return err;
1312 
1313 		count = err;
1314 
1315 		value = tegra_dsi_readl(dsi, DSI_RD_DATA);
1316 		switch (value) {
1317 		case 0x84:
1318 			/*
1319 			dev_dbg(dsi->dev, "ACK\n");
1320 			*/
1321 			break;
1322 
1323 		case 0x87:
1324 			/*
1325 			dev_dbg(dsi->dev, "ESCAPE\n");
1326 			*/
1327 			break;
1328 
1329 		default:
1330 			dev_err(dsi->dev, "unknown status: %08x\n", value);
1331 			break;
1332 		}
1333 
1334 		if (count > 1) {
1335 			err = tegra_dsi_read_response(dsi, msg, count);
1336 			if (err < 0)
1337 				dev_err(dsi->dev,
1338 					"failed to parse response: %zd\n",
1339 					err);
1340 			else {
1341 				/*
1342 				 * For read commands, return the number of
1343 				 * bytes returned by the peripheral.
1344 				 */
1345 				count = err;
1346 			}
1347 		}
1348 	} else {
1349 		/*
1350 		 * For write commands, we have transmitted the 4-byte header
1351 		 * plus the variable-length payload.
1352 		 */
1353 		count = 4 + packet.payload_length;
1354 	}
1355 
1356 	return count;
1357 }
1358 
1359 static int tegra_dsi_ganged_setup(struct tegra_dsi *dsi)
1360 {
1361 	struct clk *parent;
1362 	int err;
1363 
1364 	/* make sure both DSI controllers share the same PLL */
1365 	parent = clk_get_parent(dsi->slave->clk);
1366 	if (!parent)
1367 		return -EINVAL;
1368 
1369 	err = clk_set_parent(parent, dsi->clk_parent);
1370 	if (err < 0)
1371 		return err;
1372 
1373 	return 0;
1374 }
1375 
1376 static int tegra_dsi_host_attach(struct mipi_dsi_host *host,
1377 				 struct mipi_dsi_device *device)
1378 {
1379 	struct tegra_dsi *dsi = host_to_tegra(host);
1380 
1381 	dsi->flags = device->mode_flags;
1382 	dsi->format = device->format;
1383 	dsi->lanes = device->lanes;
1384 
1385 	if (dsi->slave) {
1386 		int err;
1387 
1388 		dev_dbg(dsi->dev, "attaching dual-channel device %s\n",
1389 			dev_name(&device->dev));
1390 
1391 		err = tegra_dsi_ganged_setup(dsi);
1392 		if (err < 0) {
1393 			dev_err(dsi->dev, "failed to set up ganged mode: %d\n",
1394 				err);
1395 			return err;
1396 		}
1397 	}
1398 
1399 	/*
1400 	 * Slaves don't have a panel associated with them, so they provide
1401 	 * merely the second channel.
1402 	 */
1403 	if (!dsi->master) {
1404 		struct tegra_output *output = &dsi->output;
1405 
1406 		output->panel = of_drm_find_panel(device->dev.of_node);
1407 		if (output->panel && output->connector.dev) {
1408 			drm_panel_attach(output->panel, &output->connector);
1409 			drm_helper_hpd_irq_event(output->connector.dev);
1410 		}
1411 	}
1412 
1413 	return 0;
1414 }
1415 
1416 static int tegra_dsi_host_detach(struct mipi_dsi_host *host,
1417 				 struct mipi_dsi_device *device)
1418 {
1419 	struct tegra_dsi *dsi = host_to_tegra(host);
1420 	struct tegra_output *output = &dsi->output;
1421 
1422 	if (output->panel && &device->dev == output->panel->dev) {
1423 		output->panel = NULL;
1424 
1425 		if (output->connector.dev)
1426 			drm_helper_hpd_irq_event(output->connector.dev);
1427 	}
1428 
1429 	return 0;
1430 }
1431 
1432 static const struct mipi_dsi_host_ops tegra_dsi_host_ops = {
1433 	.attach = tegra_dsi_host_attach,
1434 	.detach = tegra_dsi_host_detach,
1435 	.transfer = tegra_dsi_host_transfer,
1436 };
1437 
1438 static int tegra_dsi_ganged_probe(struct tegra_dsi *dsi)
1439 {
1440 	struct device_node *np;
1441 
1442 	np = of_parse_phandle(dsi->dev->of_node, "nvidia,ganged-mode", 0);
1443 	if (np) {
1444 		struct platform_device *gangster = of_find_device_by_node(np);
1445 
1446 		dsi->slave = platform_get_drvdata(gangster);
1447 		of_node_put(np);
1448 
1449 		if (!dsi->slave)
1450 			return -EPROBE_DEFER;
1451 
1452 		dsi->slave->master = dsi;
1453 	}
1454 
1455 	return 0;
1456 }
1457 
1458 static int tegra_dsi_probe(struct platform_device *pdev)
1459 {
1460 	struct tegra_dsi *dsi;
1461 	struct resource *regs;
1462 	int err;
1463 
1464 	dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
1465 	if (!dsi)
1466 		return -ENOMEM;
1467 
1468 	dsi->output.dev = dsi->dev = &pdev->dev;
1469 	dsi->video_fifo_depth = 1920;
1470 	dsi->host_fifo_depth = 64;
1471 
1472 	err = tegra_dsi_ganged_probe(dsi);
1473 	if (err < 0)
1474 		return err;
1475 
1476 	err = tegra_output_probe(&dsi->output);
1477 	if (err < 0)
1478 		return err;
1479 
1480 	dsi->output.connector.polled = DRM_CONNECTOR_POLL_HPD;
1481 
1482 	/*
1483 	 * Assume these values by default. When a DSI peripheral driver
1484 	 * attaches to the DSI host, the parameters will be taken from
1485 	 * the attached device.
1486 	 */
1487 	dsi->flags = MIPI_DSI_MODE_VIDEO;
1488 	dsi->format = MIPI_DSI_FMT_RGB888;
1489 	dsi->lanes = 4;
1490 
1491 	dsi->rst = devm_reset_control_get(&pdev->dev, "dsi");
1492 	if (IS_ERR(dsi->rst))
1493 		return PTR_ERR(dsi->rst);
1494 
1495 	dsi->clk = devm_clk_get(&pdev->dev, NULL);
1496 	if (IS_ERR(dsi->clk)) {
1497 		dev_err(&pdev->dev, "cannot get DSI clock\n");
1498 		err = PTR_ERR(dsi->clk);
1499 		goto reset;
1500 	}
1501 
1502 	err = clk_prepare_enable(dsi->clk);
1503 	if (err < 0) {
1504 		dev_err(&pdev->dev, "cannot enable DSI clock\n");
1505 		goto reset;
1506 	}
1507 
1508 	dsi->clk_lp = devm_clk_get(&pdev->dev, "lp");
1509 	if (IS_ERR(dsi->clk_lp)) {
1510 		dev_err(&pdev->dev, "cannot get low-power clock\n");
1511 		err = PTR_ERR(dsi->clk_lp);
1512 		goto disable_clk;
1513 	}
1514 
1515 	err = clk_prepare_enable(dsi->clk_lp);
1516 	if (err < 0) {
1517 		dev_err(&pdev->dev, "cannot enable low-power clock\n");
1518 		goto disable_clk;
1519 	}
1520 
1521 	dsi->clk_parent = devm_clk_get(&pdev->dev, "parent");
1522 	if (IS_ERR(dsi->clk_parent)) {
1523 		dev_err(&pdev->dev, "cannot get parent clock\n");
1524 		err = PTR_ERR(dsi->clk_parent);
1525 		goto disable_clk_lp;
1526 	}
1527 
1528 	dsi->vdd = devm_regulator_get(&pdev->dev, "avdd-dsi-csi");
1529 	if (IS_ERR(dsi->vdd)) {
1530 		dev_err(&pdev->dev, "cannot get VDD supply\n");
1531 		err = PTR_ERR(dsi->vdd);
1532 		goto disable_clk_lp;
1533 	}
1534 
1535 	err = regulator_enable(dsi->vdd);
1536 	if (err < 0) {
1537 		dev_err(&pdev->dev, "cannot enable VDD supply\n");
1538 		goto disable_clk_lp;
1539 	}
1540 
1541 	err = tegra_dsi_setup_clocks(dsi);
1542 	if (err < 0) {
1543 		dev_err(&pdev->dev, "cannot setup clocks\n");
1544 		goto disable_vdd;
1545 	}
1546 
1547 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1548 	dsi->regs = devm_ioremap_resource(&pdev->dev, regs);
1549 	if (IS_ERR(dsi->regs)) {
1550 		err = PTR_ERR(dsi->regs);
1551 		goto disable_vdd;
1552 	}
1553 
1554 	dsi->mipi = tegra_mipi_request(&pdev->dev);
1555 	if (IS_ERR(dsi->mipi)) {
1556 		err = PTR_ERR(dsi->mipi);
1557 		goto disable_vdd;
1558 	}
1559 
1560 	dsi->host.ops = &tegra_dsi_host_ops;
1561 	dsi->host.dev = &pdev->dev;
1562 
1563 	err = mipi_dsi_host_register(&dsi->host);
1564 	if (err < 0) {
1565 		dev_err(&pdev->dev, "failed to register DSI host: %d\n", err);
1566 		goto mipi_free;
1567 	}
1568 
1569 	INIT_LIST_HEAD(&dsi->client.list);
1570 	dsi->client.ops = &dsi_client_ops;
1571 	dsi->client.dev = &pdev->dev;
1572 
1573 	err = host1x_client_register(&dsi->client);
1574 	if (err < 0) {
1575 		dev_err(&pdev->dev, "failed to register host1x client: %d\n",
1576 			err);
1577 		goto unregister;
1578 	}
1579 
1580 	platform_set_drvdata(pdev, dsi);
1581 
1582 	return 0;
1583 
1584 unregister:
1585 	mipi_dsi_host_unregister(&dsi->host);
1586 mipi_free:
1587 	tegra_mipi_free(dsi->mipi);
1588 disable_vdd:
1589 	regulator_disable(dsi->vdd);
1590 disable_clk_lp:
1591 	clk_disable_unprepare(dsi->clk_lp);
1592 disable_clk:
1593 	clk_disable_unprepare(dsi->clk);
1594 reset:
1595 	reset_control_assert(dsi->rst);
1596 	return err;
1597 }
1598 
1599 static int tegra_dsi_remove(struct platform_device *pdev)
1600 {
1601 	struct tegra_dsi *dsi = platform_get_drvdata(pdev);
1602 	int err;
1603 
1604 	err = host1x_client_unregister(&dsi->client);
1605 	if (err < 0) {
1606 		dev_err(&pdev->dev, "failed to unregister host1x client: %d\n",
1607 			err);
1608 		return err;
1609 	}
1610 
1611 	tegra_output_remove(&dsi->output);
1612 
1613 	mipi_dsi_host_unregister(&dsi->host);
1614 	tegra_mipi_free(dsi->mipi);
1615 
1616 	regulator_disable(dsi->vdd);
1617 	clk_disable_unprepare(dsi->clk_lp);
1618 	clk_disable_unprepare(dsi->clk);
1619 	reset_control_assert(dsi->rst);
1620 
1621 	return 0;
1622 }
1623 
1624 static const struct of_device_id tegra_dsi_of_match[] = {
1625 	{ .compatible = "nvidia,tegra210-dsi", },
1626 	{ .compatible = "nvidia,tegra132-dsi", },
1627 	{ .compatible = "nvidia,tegra124-dsi", },
1628 	{ .compatible = "nvidia,tegra114-dsi", },
1629 	{ },
1630 };
1631 MODULE_DEVICE_TABLE(of, tegra_dsi_of_match);
1632 
1633 struct platform_driver tegra_dsi_driver = {
1634 	.driver = {
1635 		.name = "tegra-dsi",
1636 		.of_match_table = tegra_dsi_of_match,
1637 	},
1638 	.probe = tegra_dsi_probe,
1639 	.remove = tegra_dsi_remove,
1640 };
1641