xref: /openbmc/linux/drivers/gpu/drm/tegra/dsi.c (revision 80483c3a)
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/pm_runtime.h>
17 #include <linux/reset.h>
18 
19 #include <linux/regulator/consumer.h>
20 
21 #include <drm/drm_atomic_helper.h>
22 #include <drm/drm_mipi_dsi.h>
23 #include <drm/drm_panel.h>
24 
25 #include <video/mipi_display.h>
26 
27 #include "dc.h"
28 #include "drm.h"
29 #include "dsi.h"
30 #include "mipi-phy.h"
31 
32 struct tegra_dsi_state {
33 	struct drm_connector_state base;
34 
35 	struct mipi_dphy_timing timing;
36 	unsigned long period;
37 
38 	unsigned int vrefresh;
39 	unsigned int lanes;
40 	unsigned long pclk;
41 	unsigned long bclk;
42 
43 	enum tegra_dsi_format format;
44 	unsigned int mul;
45 	unsigned int div;
46 };
47 
48 static inline struct tegra_dsi_state *
49 to_dsi_state(struct drm_connector_state *state)
50 {
51 	return container_of(state, struct tegra_dsi_state, base);
52 }
53 
54 struct tegra_dsi {
55 	struct host1x_client client;
56 	struct tegra_output output;
57 	struct device *dev;
58 
59 	void __iomem *regs;
60 
61 	struct reset_control *rst;
62 	struct clk *clk_parent;
63 	struct clk *clk_lp;
64 	struct clk *clk;
65 
66 	struct drm_info_list *debugfs_files;
67 	struct drm_minor *minor;
68 	struct dentry *debugfs;
69 
70 	unsigned long flags;
71 	enum mipi_dsi_pixel_format format;
72 	unsigned int lanes;
73 
74 	struct tegra_mipi_device *mipi;
75 	struct mipi_dsi_host host;
76 
77 	struct regulator *vdd;
78 
79 	unsigned int video_fifo_depth;
80 	unsigned int host_fifo_depth;
81 
82 	/* for ganged-mode support */
83 	struct tegra_dsi *master;
84 	struct tegra_dsi *slave;
85 };
86 
87 static inline struct tegra_dsi *
88 host1x_client_to_dsi(struct host1x_client *client)
89 {
90 	return container_of(client, struct tegra_dsi, client);
91 }
92 
93 static inline struct tegra_dsi *host_to_tegra(struct mipi_dsi_host *host)
94 {
95 	return container_of(host, struct tegra_dsi, host);
96 }
97 
98 static inline struct tegra_dsi *to_dsi(struct tegra_output *output)
99 {
100 	return container_of(output, struct tegra_dsi, output);
101 }
102 
103 static struct tegra_dsi_state *tegra_dsi_get_state(struct tegra_dsi *dsi)
104 {
105 	return to_dsi_state(dsi->output.connector.state);
106 }
107 
108 static inline u32 tegra_dsi_readl(struct tegra_dsi *dsi, unsigned long reg)
109 {
110 	return readl(dsi->regs + (reg << 2));
111 }
112 
113 static inline void tegra_dsi_writel(struct tegra_dsi *dsi, u32 value,
114 				    unsigned long reg)
115 {
116 	writel(value, dsi->regs + (reg << 2));
117 }
118 
119 static int tegra_dsi_show_regs(struct seq_file *s, void *data)
120 {
121 	struct drm_info_node *node = s->private;
122 	struct tegra_dsi *dsi = node->info_ent->data;
123 	struct drm_crtc *crtc = dsi->output.encoder.crtc;
124 	struct drm_device *drm = node->minor->dev;
125 	int err = 0;
126 
127 	drm_modeset_lock_all(drm);
128 
129 	if (!crtc || !crtc->state->active) {
130 		err = -EBUSY;
131 		goto unlock;
132 	}
133 
134 #define DUMP_REG(name)						\
135 	seq_printf(s, "%-32s %#05x %08x\n", #name, name,	\
136 		   tegra_dsi_readl(dsi, name))
137 
138 	DUMP_REG(DSI_INCR_SYNCPT);
139 	DUMP_REG(DSI_INCR_SYNCPT_CONTROL);
140 	DUMP_REG(DSI_INCR_SYNCPT_ERROR);
141 	DUMP_REG(DSI_CTXSW);
142 	DUMP_REG(DSI_RD_DATA);
143 	DUMP_REG(DSI_WR_DATA);
144 	DUMP_REG(DSI_POWER_CONTROL);
145 	DUMP_REG(DSI_INT_ENABLE);
146 	DUMP_REG(DSI_INT_STATUS);
147 	DUMP_REG(DSI_INT_MASK);
148 	DUMP_REG(DSI_HOST_CONTROL);
149 	DUMP_REG(DSI_CONTROL);
150 	DUMP_REG(DSI_SOL_DELAY);
151 	DUMP_REG(DSI_MAX_THRESHOLD);
152 	DUMP_REG(DSI_TRIGGER);
153 	DUMP_REG(DSI_TX_CRC);
154 	DUMP_REG(DSI_STATUS);
155 
156 	DUMP_REG(DSI_INIT_SEQ_CONTROL);
157 	DUMP_REG(DSI_INIT_SEQ_DATA_0);
158 	DUMP_REG(DSI_INIT_SEQ_DATA_1);
159 	DUMP_REG(DSI_INIT_SEQ_DATA_2);
160 	DUMP_REG(DSI_INIT_SEQ_DATA_3);
161 	DUMP_REG(DSI_INIT_SEQ_DATA_4);
162 	DUMP_REG(DSI_INIT_SEQ_DATA_5);
163 	DUMP_REG(DSI_INIT_SEQ_DATA_6);
164 	DUMP_REG(DSI_INIT_SEQ_DATA_7);
165 
166 	DUMP_REG(DSI_PKT_SEQ_0_LO);
167 	DUMP_REG(DSI_PKT_SEQ_0_HI);
168 	DUMP_REG(DSI_PKT_SEQ_1_LO);
169 	DUMP_REG(DSI_PKT_SEQ_1_HI);
170 	DUMP_REG(DSI_PKT_SEQ_2_LO);
171 	DUMP_REG(DSI_PKT_SEQ_2_HI);
172 	DUMP_REG(DSI_PKT_SEQ_3_LO);
173 	DUMP_REG(DSI_PKT_SEQ_3_HI);
174 	DUMP_REG(DSI_PKT_SEQ_4_LO);
175 	DUMP_REG(DSI_PKT_SEQ_4_HI);
176 	DUMP_REG(DSI_PKT_SEQ_5_LO);
177 	DUMP_REG(DSI_PKT_SEQ_5_HI);
178 
179 	DUMP_REG(DSI_DCS_CMDS);
180 
181 	DUMP_REG(DSI_PKT_LEN_0_1);
182 	DUMP_REG(DSI_PKT_LEN_2_3);
183 	DUMP_REG(DSI_PKT_LEN_4_5);
184 	DUMP_REG(DSI_PKT_LEN_6_7);
185 
186 	DUMP_REG(DSI_PHY_TIMING_0);
187 	DUMP_REG(DSI_PHY_TIMING_1);
188 	DUMP_REG(DSI_PHY_TIMING_2);
189 	DUMP_REG(DSI_BTA_TIMING);
190 
191 	DUMP_REG(DSI_TIMEOUT_0);
192 	DUMP_REG(DSI_TIMEOUT_1);
193 	DUMP_REG(DSI_TO_TALLY);
194 
195 	DUMP_REG(DSI_PAD_CONTROL_0);
196 	DUMP_REG(DSI_PAD_CONTROL_CD);
197 	DUMP_REG(DSI_PAD_CD_STATUS);
198 	DUMP_REG(DSI_VIDEO_MODE_CONTROL);
199 	DUMP_REG(DSI_PAD_CONTROL_1);
200 	DUMP_REG(DSI_PAD_CONTROL_2);
201 	DUMP_REG(DSI_PAD_CONTROL_3);
202 	DUMP_REG(DSI_PAD_CONTROL_4);
203 
204 	DUMP_REG(DSI_GANGED_MODE_CONTROL);
205 	DUMP_REG(DSI_GANGED_MODE_START);
206 	DUMP_REG(DSI_GANGED_MODE_SIZE);
207 
208 	DUMP_REG(DSI_RAW_DATA_BYTE_COUNT);
209 	DUMP_REG(DSI_ULTRA_LOW_POWER_CONTROL);
210 
211 	DUMP_REG(DSI_INIT_SEQ_DATA_8);
212 	DUMP_REG(DSI_INIT_SEQ_DATA_9);
213 	DUMP_REG(DSI_INIT_SEQ_DATA_10);
214 	DUMP_REG(DSI_INIT_SEQ_DATA_11);
215 	DUMP_REG(DSI_INIT_SEQ_DATA_12);
216 	DUMP_REG(DSI_INIT_SEQ_DATA_13);
217 	DUMP_REG(DSI_INIT_SEQ_DATA_14);
218 	DUMP_REG(DSI_INIT_SEQ_DATA_15);
219 
220 #undef DUMP_REG
221 
222 unlock:
223 	drm_modeset_unlock_all(drm);
224 	return err;
225 }
226 
227 static struct drm_info_list debugfs_files[] = {
228 	{ "regs", tegra_dsi_show_regs, 0, NULL },
229 };
230 
231 static int tegra_dsi_debugfs_init(struct tegra_dsi *dsi,
232 				  struct drm_minor *minor)
233 {
234 	const char *name = dev_name(dsi->dev);
235 	unsigned int i;
236 	int err;
237 
238 	dsi->debugfs = debugfs_create_dir(name, minor->debugfs_root);
239 	if (!dsi->debugfs)
240 		return -ENOMEM;
241 
242 	dsi->debugfs_files = kmemdup(debugfs_files, sizeof(debugfs_files),
243 				     GFP_KERNEL);
244 	if (!dsi->debugfs_files) {
245 		err = -ENOMEM;
246 		goto remove;
247 	}
248 
249 	for (i = 0; i < ARRAY_SIZE(debugfs_files); i++)
250 		dsi->debugfs_files[i].data = dsi;
251 
252 	err = drm_debugfs_create_files(dsi->debugfs_files,
253 				       ARRAY_SIZE(debugfs_files),
254 				       dsi->debugfs, minor);
255 	if (err < 0)
256 		goto free;
257 
258 	dsi->minor = minor;
259 
260 	return 0;
261 
262 free:
263 	kfree(dsi->debugfs_files);
264 	dsi->debugfs_files = NULL;
265 remove:
266 	debugfs_remove(dsi->debugfs);
267 	dsi->debugfs = NULL;
268 
269 	return err;
270 }
271 
272 static void tegra_dsi_debugfs_exit(struct tegra_dsi *dsi)
273 {
274 	drm_debugfs_remove_files(dsi->debugfs_files, ARRAY_SIZE(debugfs_files),
275 				 dsi->minor);
276 	dsi->minor = NULL;
277 
278 	kfree(dsi->debugfs_files);
279 	dsi->debugfs_files = NULL;
280 
281 	debugfs_remove(dsi->debugfs);
282 	dsi->debugfs = NULL;
283 }
284 
285 #define PKT_ID0(id)	((((id) & 0x3f) <<  3) | (1 <<  9))
286 #define PKT_LEN0(len)	(((len) & 0x07) <<  0)
287 #define PKT_ID1(id)	((((id) & 0x3f) << 13) | (1 << 19))
288 #define PKT_LEN1(len)	(((len) & 0x07) << 10)
289 #define PKT_ID2(id)	((((id) & 0x3f) << 23) | (1 << 29))
290 #define PKT_LEN2(len)	(((len) & 0x07) << 20)
291 
292 #define PKT_LP		(1 << 30)
293 #define NUM_PKT_SEQ	12
294 
295 /*
296  * non-burst mode with sync pulses
297  */
298 static const u32 pkt_seq_video_non_burst_sync_pulses[NUM_PKT_SEQ] = {
299 	[ 0] = PKT_ID0(MIPI_DSI_V_SYNC_START) | PKT_LEN0(0) |
300 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
301 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
302 	       PKT_LP,
303 	[ 1] = 0,
304 	[ 2] = PKT_ID0(MIPI_DSI_V_SYNC_END) | PKT_LEN0(0) |
305 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
306 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
307 	       PKT_LP,
308 	[ 3] = 0,
309 	[ 4] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
310 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
311 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
312 	       PKT_LP,
313 	[ 5] = 0,
314 	[ 6] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
315 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
316 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0),
317 	[ 7] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(2) |
318 	       PKT_ID1(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN1(3) |
319 	       PKT_ID2(MIPI_DSI_BLANKING_PACKET) | PKT_LEN2(4),
320 	[ 8] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
321 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
322 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
323 	       PKT_LP,
324 	[ 9] = 0,
325 	[10] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
326 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
327 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0),
328 	[11] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(2) |
329 	       PKT_ID1(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN1(3) |
330 	       PKT_ID2(MIPI_DSI_BLANKING_PACKET) | PKT_LEN2(4),
331 };
332 
333 /*
334  * non-burst mode with sync events
335  */
336 static const u32 pkt_seq_video_non_burst_sync_events[NUM_PKT_SEQ] = {
337 	[ 0] = PKT_ID0(MIPI_DSI_V_SYNC_START) | PKT_LEN0(0) |
338 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
339 	       PKT_LP,
340 	[ 1] = 0,
341 	[ 2] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
342 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
343 	       PKT_LP,
344 	[ 3] = 0,
345 	[ 4] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
346 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
347 	       PKT_LP,
348 	[ 5] = 0,
349 	[ 6] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
350 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(2) |
351 	       PKT_ID2(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN2(3),
352 	[ 7] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(4),
353 	[ 8] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
354 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
355 	       PKT_LP,
356 	[ 9] = 0,
357 	[10] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
358 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(2) |
359 	       PKT_ID2(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN2(3),
360 	[11] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(4),
361 };
362 
363 static const u32 pkt_seq_command_mode[NUM_PKT_SEQ] = {
364 	[ 0] = 0,
365 	[ 1] = 0,
366 	[ 2] = 0,
367 	[ 3] = 0,
368 	[ 4] = 0,
369 	[ 5] = 0,
370 	[ 6] = PKT_ID0(MIPI_DSI_DCS_LONG_WRITE) | PKT_LEN0(3) | PKT_LP,
371 	[ 7] = 0,
372 	[ 8] = 0,
373 	[ 9] = 0,
374 	[10] = PKT_ID0(MIPI_DSI_DCS_LONG_WRITE) | PKT_LEN0(5) | PKT_LP,
375 	[11] = 0,
376 };
377 
378 static void tegra_dsi_set_phy_timing(struct tegra_dsi *dsi,
379 				     unsigned long period,
380 				     const struct mipi_dphy_timing *timing)
381 {
382 	u32 value;
383 
384 	value = DSI_TIMING_FIELD(timing->hsexit, period, 1) << 24 |
385 		DSI_TIMING_FIELD(timing->hstrail, period, 0) << 16 |
386 		DSI_TIMING_FIELD(timing->hszero, period, 3) << 8 |
387 		DSI_TIMING_FIELD(timing->hsprepare, period, 1);
388 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_0);
389 
390 	value = DSI_TIMING_FIELD(timing->clktrail, period, 1) << 24 |
391 		DSI_TIMING_FIELD(timing->clkpost, period, 1) << 16 |
392 		DSI_TIMING_FIELD(timing->clkzero, period, 1) << 8 |
393 		DSI_TIMING_FIELD(timing->lpx, period, 1);
394 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_1);
395 
396 	value = DSI_TIMING_FIELD(timing->clkprepare, period, 1) << 16 |
397 		DSI_TIMING_FIELD(timing->clkpre, period, 1) << 8 |
398 		DSI_TIMING_FIELD(0xff * period, period, 0) << 0;
399 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_2);
400 
401 	value = DSI_TIMING_FIELD(timing->taget, period, 1) << 16 |
402 		DSI_TIMING_FIELD(timing->tasure, period, 1) << 8 |
403 		DSI_TIMING_FIELD(timing->tago, period, 1);
404 	tegra_dsi_writel(dsi, value, DSI_BTA_TIMING);
405 
406 	if (dsi->slave)
407 		tegra_dsi_set_phy_timing(dsi->slave, period, timing);
408 }
409 
410 static int tegra_dsi_get_muldiv(enum mipi_dsi_pixel_format format,
411 				unsigned int *mulp, unsigned int *divp)
412 {
413 	switch (format) {
414 	case MIPI_DSI_FMT_RGB666_PACKED:
415 	case MIPI_DSI_FMT_RGB888:
416 		*mulp = 3;
417 		*divp = 1;
418 		break;
419 
420 	case MIPI_DSI_FMT_RGB565:
421 		*mulp = 2;
422 		*divp = 1;
423 		break;
424 
425 	case MIPI_DSI_FMT_RGB666:
426 		*mulp = 9;
427 		*divp = 4;
428 		break;
429 
430 	default:
431 		return -EINVAL;
432 	}
433 
434 	return 0;
435 }
436 
437 static int tegra_dsi_get_format(enum mipi_dsi_pixel_format format,
438 				enum tegra_dsi_format *fmt)
439 {
440 	switch (format) {
441 	case MIPI_DSI_FMT_RGB888:
442 		*fmt = TEGRA_DSI_FORMAT_24P;
443 		break;
444 
445 	case MIPI_DSI_FMT_RGB666:
446 		*fmt = TEGRA_DSI_FORMAT_18NP;
447 		break;
448 
449 	case MIPI_DSI_FMT_RGB666_PACKED:
450 		*fmt = TEGRA_DSI_FORMAT_18P;
451 		break;
452 
453 	case MIPI_DSI_FMT_RGB565:
454 		*fmt = TEGRA_DSI_FORMAT_16P;
455 		break;
456 
457 	default:
458 		return -EINVAL;
459 	}
460 
461 	return 0;
462 }
463 
464 static void tegra_dsi_ganged_enable(struct tegra_dsi *dsi, unsigned int start,
465 				    unsigned int size)
466 {
467 	u32 value;
468 
469 	tegra_dsi_writel(dsi, start, DSI_GANGED_MODE_START);
470 	tegra_dsi_writel(dsi, size << 16 | size, DSI_GANGED_MODE_SIZE);
471 
472 	value = DSI_GANGED_MODE_CONTROL_ENABLE;
473 	tegra_dsi_writel(dsi, value, DSI_GANGED_MODE_CONTROL);
474 }
475 
476 static void tegra_dsi_enable(struct tegra_dsi *dsi)
477 {
478 	u32 value;
479 
480 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
481 	value |= DSI_POWER_CONTROL_ENABLE;
482 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
483 
484 	if (dsi->slave)
485 		tegra_dsi_enable(dsi->slave);
486 }
487 
488 static unsigned int tegra_dsi_get_lanes(struct tegra_dsi *dsi)
489 {
490 	if (dsi->master)
491 		return dsi->master->lanes + dsi->lanes;
492 
493 	if (dsi->slave)
494 		return dsi->lanes + dsi->slave->lanes;
495 
496 	return dsi->lanes;
497 }
498 
499 static void tegra_dsi_configure(struct tegra_dsi *dsi, unsigned int pipe,
500 				const struct drm_display_mode *mode)
501 {
502 	unsigned int hact, hsw, hbp, hfp, i, mul, div;
503 	struct tegra_dsi_state *state;
504 	const u32 *pkt_seq;
505 	u32 value;
506 
507 	/* XXX: pass in state into this function? */
508 	if (dsi->master)
509 		state = tegra_dsi_get_state(dsi->master);
510 	else
511 		state = tegra_dsi_get_state(dsi);
512 
513 	mul = state->mul;
514 	div = state->div;
515 
516 	if (dsi->flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
517 		DRM_DEBUG_KMS("Non-burst video mode with sync pulses\n");
518 		pkt_seq = pkt_seq_video_non_burst_sync_pulses;
519 	} else if (dsi->flags & MIPI_DSI_MODE_VIDEO) {
520 		DRM_DEBUG_KMS("Non-burst video mode with sync events\n");
521 		pkt_seq = pkt_seq_video_non_burst_sync_events;
522 	} else {
523 		DRM_DEBUG_KMS("Command mode\n");
524 		pkt_seq = pkt_seq_command_mode;
525 	}
526 
527 	value = DSI_CONTROL_CHANNEL(0) |
528 		DSI_CONTROL_FORMAT(state->format) |
529 		DSI_CONTROL_LANES(dsi->lanes - 1) |
530 		DSI_CONTROL_SOURCE(pipe);
531 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
532 
533 	tegra_dsi_writel(dsi, dsi->video_fifo_depth, DSI_MAX_THRESHOLD);
534 
535 	value = DSI_HOST_CONTROL_HS;
536 	tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
537 
538 	value = tegra_dsi_readl(dsi, DSI_CONTROL);
539 
540 	if (dsi->flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)
541 		value |= DSI_CONTROL_HS_CLK_CTRL;
542 
543 	value &= ~DSI_CONTROL_TX_TRIG(3);
544 
545 	/* enable DCS commands for command mode */
546 	if (dsi->flags & MIPI_DSI_MODE_VIDEO)
547 		value &= ~DSI_CONTROL_DCS_ENABLE;
548 	else
549 		value |= DSI_CONTROL_DCS_ENABLE;
550 
551 	value |= DSI_CONTROL_VIDEO_ENABLE;
552 	value &= ~DSI_CONTROL_HOST_ENABLE;
553 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
554 
555 	for (i = 0; i < NUM_PKT_SEQ; i++)
556 		tegra_dsi_writel(dsi, pkt_seq[i], DSI_PKT_SEQ_0_LO + i);
557 
558 	if (dsi->flags & MIPI_DSI_MODE_VIDEO) {
559 		/* horizontal active pixels */
560 		hact = mode->hdisplay * mul / div;
561 
562 		/* horizontal sync width */
563 		hsw = (mode->hsync_end - mode->hsync_start) * mul / div;
564 
565 		/* horizontal back porch */
566 		hbp = (mode->htotal - mode->hsync_end) * mul / div;
567 
568 		if ((dsi->flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) == 0)
569 			hbp += hsw;
570 
571 		/* horizontal front porch */
572 		hfp = (mode->hsync_start - mode->hdisplay) * mul / div;
573 
574 		/* subtract packet overhead */
575 		hsw -= 10;
576 		hbp -= 14;
577 		hfp -= 8;
578 
579 		tegra_dsi_writel(dsi, hsw << 16 | 0, DSI_PKT_LEN_0_1);
580 		tegra_dsi_writel(dsi, hact << 16 | hbp, DSI_PKT_LEN_2_3);
581 		tegra_dsi_writel(dsi, hfp, DSI_PKT_LEN_4_5);
582 		tegra_dsi_writel(dsi, 0x0f0f << 16, DSI_PKT_LEN_6_7);
583 
584 		/* set SOL delay (for non-burst mode only) */
585 		tegra_dsi_writel(dsi, 8 * mul / div, DSI_SOL_DELAY);
586 
587 		/* TODO: implement ganged mode */
588 	} else {
589 		u16 bytes;
590 
591 		if (dsi->master || dsi->slave) {
592 			/*
593 			 * For ganged mode, assume symmetric left-right mode.
594 			 */
595 			bytes = 1 + (mode->hdisplay / 2) * mul / div;
596 		} else {
597 			/* 1 byte (DCS command) + pixel data */
598 			bytes = 1 + mode->hdisplay * mul / div;
599 		}
600 
601 		tegra_dsi_writel(dsi, 0, DSI_PKT_LEN_0_1);
602 		tegra_dsi_writel(dsi, bytes << 16, DSI_PKT_LEN_2_3);
603 		tegra_dsi_writel(dsi, bytes << 16, DSI_PKT_LEN_4_5);
604 		tegra_dsi_writel(dsi, 0, DSI_PKT_LEN_6_7);
605 
606 		value = MIPI_DCS_WRITE_MEMORY_START << 8 |
607 			MIPI_DCS_WRITE_MEMORY_CONTINUE;
608 		tegra_dsi_writel(dsi, value, DSI_DCS_CMDS);
609 
610 		/* set SOL delay */
611 		if (dsi->master || dsi->slave) {
612 			unsigned long delay, bclk, bclk_ganged;
613 			unsigned int lanes = state->lanes;
614 
615 			/* SOL to valid, valid to FIFO and FIFO write delay */
616 			delay = 4 + 4 + 2;
617 			delay = DIV_ROUND_UP(delay * mul, div * lanes);
618 			/* FIFO read delay */
619 			delay = delay + 6;
620 
621 			bclk = DIV_ROUND_UP(mode->htotal * mul, div * lanes);
622 			bclk_ganged = DIV_ROUND_UP(bclk * lanes / 2, lanes);
623 			value = bclk - bclk_ganged + delay + 20;
624 		} else {
625 			/* TODO: revisit for non-ganged mode */
626 			value = 8 * mul / div;
627 		}
628 
629 		tegra_dsi_writel(dsi, value, DSI_SOL_DELAY);
630 	}
631 
632 	if (dsi->slave) {
633 		tegra_dsi_configure(dsi->slave, pipe, mode);
634 
635 		/*
636 		 * TODO: Support modes other than symmetrical left-right
637 		 * split.
638 		 */
639 		tegra_dsi_ganged_enable(dsi, 0, mode->hdisplay / 2);
640 		tegra_dsi_ganged_enable(dsi->slave, mode->hdisplay / 2,
641 					mode->hdisplay / 2);
642 	}
643 }
644 
645 static int tegra_dsi_wait_idle(struct tegra_dsi *dsi, unsigned long timeout)
646 {
647 	u32 value;
648 
649 	timeout = jiffies + msecs_to_jiffies(timeout);
650 
651 	while (time_before(jiffies, timeout)) {
652 		value = tegra_dsi_readl(dsi, DSI_STATUS);
653 		if (value & DSI_STATUS_IDLE)
654 			return 0;
655 
656 		usleep_range(1000, 2000);
657 	}
658 
659 	return -ETIMEDOUT;
660 }
661 
662 static void tegra_dsi_video_disable(struct tegra_dsi *dsi)
663 {
664 	u32 value;
665 
666 	value = tegra_dsi_readl(dsi, DSI_CONTROL);
667 	value &= ~DSI_CONTROL_VIDEO_ENABLE;
668 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
669 
670 	if (dsi->slave)
671 		tegra_dsi_video_disable(dsi->slave);
672 }
673 
674 static void tegra_dsi_ganged_disable(struct tegra_dsi *dsi)
675 {
676 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_START);
677 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_SIZE);
678 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_CONTROL);
679 }
680 
681 static int tegra_dsi_pad_enable(struct tegra_dsi *dsi)
682 {
683 	u32 value;
684 
685 	value = DSI_PAD_CONTROL_VS1_PULLDN(0) | DSI_PAD_CONTROL_VS1_PDIO(0);
686 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_0);
687 
688 	return 0;
689 }
690 
691 static int tegra_dsi_pad_calibrate(struct tegra_dsi *dsi)
692 {
693 	u32 value;
694 
695 	/*
696 	 * XXX Is this still needed? The module reset is deasserted right
697 	 * before this function is called.
698 	 */
699 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_0);
700 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_1);
701 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_2);
702 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_3);
703 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_4);
704 
705 	/* start calibration */
706 	tegra_dsi_pad_enable(dsi);
707 
708 	value = DSI_PAD_SLEW_UP(0x7) | DSI_PAD_SLEW_DN(0x7) |
709 		DSI_PAD_LP_UP(0x1) | DSI_PAD_LP_DN(0x1) |
710 		DSI_PAD_OUT_CLK(0x0);
711 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_2);
712 
713 	value = DSI_PAD_PREEMP_PD_CLK(0x3) | DSI_PAD_PREEMP_PU_CLK(0x3) |
714 		DSI_PAD_PREEMP_PD(0x03) | DSI_PAD_PREEMP_PU(0x3);
715 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_3);
716 
717 	return tegra_mipi_calibrate(dsi->mipi);
718 }
719 
720 static void tegra_dsi_set_timeout(struct tegra_dsi *dsi, unsigned long bclk,
721 				  unsigned int vrefresh)
722 {
723 	unsigned int timeout;
724 	u32 value;
725 
726 	/* one frame high-speed transmission timeout */
727 	timeout = (bclk / vrefresh) / 512;
728 	value = DSI_TIMEOUT_LRX(0x2000) | DSI_TIMEOUT_HTX(timeout);
729 	tegra_dsi_writel(dsi, value, DSI_TIMEOUT_0);
730 
731 	/* 2 ms peripheral timeout for panel */
732 	timeout = 2 * bclk / 512 * 1000;
733 	value = DSI_TIMEOUT_PR(timeout) | DSI_TIMEOUT_TA(0x2000);
734 	tegra_dsi_writel(dsi, value, DSI_TIMEOUT_1);
735 
736 	value = DSI_TALLY_TA(0) | DSI_TALLY_LRX(0) | DSI_TALLY_HTX(0);
737 	tegra_dsi_writel(dsi, value, DSI_TO_TALLY);
738 
739 	if (dsi->slave)
740 		tegra_dsi_set_timeout(dsi->slave, bclk, vrefresh);
741 }
742 
743 static void tegra_dsi_disable(struct tegra_dsi *dsi)
744 {
745 	u32 value;
746 
747 	if (dsi->slave) {
748 		tegra_dsi_ganged_disable(dsi->slave);
749 		tegra_dsi_ganged_disable(dsi);
750 	}
751 
752 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
753 	value &= ~DSI_POWER_CONTROL_ENABLE;
754 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
755 
756 	if (dsi->slave)
757 		tegra_dsi_disable(dsi->slave);
758 
759 	usleep_range(5000, 10000);
760 }
761 
762 static void tegra_dsi_soft_reset(struct tegra_dsi *dsi)
763 {
764 	u32 value;
765 
766 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
767 	value &= ~DSI_POWER_CONTROL_ENABLE;
768 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
769 
770 	usleep_range(300, 1000);
771 
772 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
773 	value |= DSI_POWER_CONTROL_ENABLE;
774 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
775 
776 	usleep_range(300, 1000);
777 
778 	value = tegra_dsi_readl(dsi, DSI_TRIGGER);
779 	if (value)
780 		tegra_dsi_writel(dsi, 0, DSI_TRIGGER);
781 
782 	if (dsi->slave)
783 		tegra_dsi_soft_reset(dsi->slave);
784 }
785 
786 static void tegra_dsi_connector_reset(struct drm_connector *connector)
787 {
788 	struct tegra_dsi_state *state = kzalloc(sizeof(*state), GFP_KERNEL);
789 
790 	if (!state)
791 		return;
792 
793 	if (connector->state) {
794 		__drm_atomic_helper_connector_destroy_state(connector->state);
795 		kfree(connector->state);
796 	}
797 
798 	__drm_atomic_helper_connector_reset(connector, &state->base);
799 }
800 
801 static struct drm_connector_state *
802 tegra_dsi_connector_duplicate_state(struct drm_connector *connector)
803 {
804 	struct tegra_dsi_state *state = to_dsi_state(connector->state);
805 	struct tegra_dsi_state *copy;
806 
807 	copy = kmemdup(state, sizeof(*state), GFP_KERNEL);
808 	if (!copy)
809 		return NULL;
810 
811 	__drm_atomic_helper_connector_duplicate_state(connector,
812 						      &copy->base);
813 
814 	return &copy->base;
815 }
816 
817 static const struct drm_connector_funcs tegra_dsi_connector_funcs = {
818 	.dpms = drm_atomic_helper_connector_dpms,
819 	.reset = tegra_dsi_connector_reset,
820 	.detect = tegra_output_connector_detect,
821 	.fill_modes = drm_helper_probe_single_connector_modes,
822 	.destroy = tegra_output_connector_destroy,
823 	.atomic_duplicate_state = tegra_dsi_connector_duplicate_state,
824 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
825 };
826 
827 static enum drm_mode_status
828 tegra_dsi_connector_mode_valid(struct drm_connector *connector,
829 			       struct drm_display_mode *mode)
830 {
831 	return MODE_OK;
832 }
833 
834 static const struct drm_connector_helper_funcs tegra_dsi_connector_helper_funcs = {
835 	.get_modes = tegra_output_connector_get_modes,
836 	.mode_valid = tegra_dsi_connector_mode_valid,
837 };
838 
839 static const struct drm_encoder_funcs tegra_dsi_encoder_funcs = {
840 	.destroy = tegra_output_encoder_destroy,
841 };
842 
843 static void tegra_dsi_encoder_disable(struct drm_encoder *encoder)
844 {
845 	struct tegra_output *output = encoder_to_output(encoder);
846 	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
847 	struct tegra_dsi *dsi = to_dsi(output);
848 	u32 value;
849 	int err;
850 
851 	if (output->panel)
852 		drm_panel_disable(output->panel);
853 
854 	tegra_dsi_video_disable(dsi);
855 
856 	/*
857 	 * The following accesses registers of the display controller, so make
858 	 * sure it's only executed when the output is attached to one.
859 	 */
860 	if (dc) {
861 		value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
862 		value &= ~DSI_ENABLE;
863 		tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
864 
865 		tegra_dc_commit(dc);
866 	}
867 
868 	err = tegra_dsi_wait_idle(dsi, 100);
869 	if (err < 0)
870 		dev_dbg(dsi->dev, "failed to idle DSI: %d\n", err);
871 
872 	tegra_dsi_soft_reset(dsi);
873 
874 	if (output->panel)
875 		drm_panel_unprepare(output->panel);
876 
877 	tegra_dsi_disable(dsi);
878 
879 	pm_runtime_put(dsi->dev);
880 }
881 
882 static void tegra_dsi_encoder_enable(struct drm_encoder *encoder)
883 {
884 	struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode;
885 	struct tegra_output *output = encoder_to_output(encoder);
886 	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
887 	struct tegra_dsi *dsi = to_dsi(output);
888 	struct tegra_dsi_state *state;
889 	u32 value;
890 	int err;
891 
892 	pm_runtime_get_sync(dsi->dev);
893 
894 	err = tegra_dsi_pad_calibrate(dsi);
895 	if (err < 0)
896 		dev_err(dsi->dev, "MIPI calibration failed: %d\n", err);
897 
898 	state = tegra_dsi_get_state(dsi);
899 
900 	tegra_dsi_set_timeout(dsi, state->bclk, state->vrefresh);
901 
902 	/*
903 	 * The D-PHY timing fields are expressed in byte-clock cycles, so
904 	 * multiply the period by 8.
905 	 */
906 	tegra_dsi_set_phy_timing(dsi, state->period * 8, &state->timing);
907 
908 	if (output->panel)
909 		drm_panel_prepare(output->panel);
910 
911 	tegra_dsi_configure(dsi, dc->pipe, mode);
912 
913 	/* enable display controller */
914 	value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
915 	value |= DSI_ENABLE;
916 	tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
917 
918 	tegra_dc_commit(dc);
919 
920 	/* enable DSI controller */
921 	tegra_dsi_enable(dsi);
922 
923 	if (output->panel)
924 		drm_panel_enable(output->panel);
925 }
926 
927 static int
928 tegra_dsi_encoder_atomic_check(struct drm_encoder *encoder,
929 			       struct drm_crtc_state *crtc_state,
930 			       struct drm_connector_state *conn_state)
931 {
932 	struct tegra_output *output = encoder_to_output(encoder);
933 	struct tegra_dsi_state *state = to_dsi_state(conn_state);
934 	struct tegra_dc *dc = to_tegra_dc(conn_state->crtc);
935 	struct tegra_dsi *dsi = to_dsi(output);
936 	unsigned int scdiv;
937 	unsigned long plld;
938 	int err;
939 
940 	state->pclk = crtc_state->mode.clock * 1000;
941 
942 	err = tegra_dsi_get_muldiv(dsi->format, &state->mul, &state->div);
943 	if (err < 0)
944 		return err;
945 
946 	state->lanes = tegra_dsi_get_lanes(dsi);
947 
948 	err = tegra_dsi_get_format(dsi->format, &state->format);
949 	if (err < 0)
950 		return err;
951 
952 	state->vrefresh = drm_mode_vrefresh(&crtc_state->mode);
953 
954 	/* compute byte clock */
955 	state->bclk = (state->pclk * state->mul) / (state->div * state->lanes);
956 
957 	DRM_DEBUG_KMS("mul: %u, div: %u, lanes: %u\n", state->mul, state->div,
958 		      state->lanes);
959 	DRM_DEBUG_KMS("format: %u, vrefresh: %u\n", state->format,
960 		      state->vrefresh);
961 	DRM_DEBUG_KMS("bclk: %lu\n", state->bclk);
962 
963 	/*
964 	 * Compute bit clock and round up to the next MHz.
965 	 */
966 	plld = DIV_ROUND_UP(state->bclk * 8, USEC_PER_SEC) * USEC_PER_SEC;
967 	state->period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, plld);
968 
969 	err = mipi_dphy_timing_get_default(&state->timing, state->period);
970 	if (err < 0)
971 		return err;
972 
973 	err = mipi_dphy_timing_validate(&state->timing, state->period);
974 	if (err < 0) {
975 		dev_err(dsi->dev, "failed to validate D-PHY timing: %d\n", err);
976 		return err;
977 	}
978 
979 	/*
980 	 * We divide the frequency by two here, but we make up for that by
981 	 * setting the shift clock divider (further below) to half of the
982 	 * correct value.
983 	 */
984 	plld /= 2;
985 
986 	/*
987 	 * Derive pixel clock from bit clock using the shift clock divider.
988 	 * Note that this is only half of what we would expect, but we need
989 	 * that to make up for the fact that we divided the bit clock by a
990 	 * factor of two above.
991 	 *
992 	 * It's not clear exactly why this is necessary, but the display is
993 	 * not working properly otherwise. Perhaps the PLLs cannot generate
994 	 * frequencies sufficiently high.
995 	 */
996 	scdiv = ((8 * state->mul) / (state->div * state->lanes)) - 2;
997 
998 	err = tegra_dc_state_setup_clock(dc, crtc_state, dsi->clk_parent,
999 					 plld, scdiv);
1000 	if (err < 0) {
1001 		dev_err(output->dev, "failed to setup CRTC state: %d\n", err);
1002 		return err;
1003 	}
1004 
1005 	return err;
1006 }
1007 
1008 static const struct drm_encoder_helper_funcs tegra_dsi_encoder_helper_funcs = {
1009 	.disable = tegra_dsi_encoder_disable,
1010 	.enable = tegra_dsi_encoder_enable,
1011 	.atomic_check = tegra_dsi_encoder_atomic_check,
1012 };
1013 
1014 static int tegra_dsi_init(struct host1x_client *client)
1015 {
1016 	struct drm_device *drm = dev_get_drvdata(client->parent);
1017 	struct tegra_dsi *dsi = host1x_client_to_dsi(client);
1018 	int err;
1019 
1020 	/* Gangsters must not register their own outputs. */
1021 	if (!dsi->master) {
1022 		dsi->output.dev = client->dev;
1023 
1024 		drm_connector_init(drm, &dsi->output.connector,
1025 				   &tegra_dsi_connector_funcs,
1026 				   DRM_MODE_CONNECTOR_DSI);
1027 		drm_connector_helper_add(&dsi->output.connector,
1028 					 &tegra_dsi_connector_helper_funcs);
1029 		dsi->output.connector.dpms = DRM_MODE_DPMS_OFF;
1030 
1031 		drm_encoder_init(drm, &dsi->output.encoder,
1032 				 &tegra_dsi_encoder_funcs,
1033 				 DRM_MODE_ENCODER_DSI, NULL);
1034 		drm_encoder_helper_add(&dsi->output.encoder,
1035 				       &tegra_dsi_encoder_helper_funcs);
1036 
1037 		drm_mode_connector_attach_encoder(&dsi->output.connector,
1038 						  &dsi->output.encoder);
1039 		drm_connector_register(&dsi->output.connector);
1040 
1041 		err = tegra_output_init(drm, &dsi->output);
1042 		if (err < 0)
1043 			dev_err(dsi->dev, "failed to initialize output: %d\n",
1044 				err);
1045 
1046 		dsi->output.encoder.possible_crtcs = 0x3;
1047 	}
1048 
1049 	if (IS_ENABLED(CONFIG_DEBUG_FS)) {
1050 		err = tegra_dsi_debugfs_init(dsi, drm->primary);
1051 		if (err < 0)
1052 			dev_err(dsi->dev, "debugfs setup failed: %d\n", err);
1053 	}
1054 
1055 	return 0;
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 	regulator_disable(dsi->vdd);
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 	if (!pdev->dev.pm_domain) {
1492 		dsi->rst = devm_reset_control_get(&pdev->dev, "dsi");
1493 		if (IS_ERR(dsi->rst))
1494 			return PTR_ERR(dsi->rst);
1495 	}
1496 
1497 	dsi->clk = devm_clk_get(&pdev->dev, NULL);
1498 	if (IS_ERR(dsi->clk)) {
1499 		dev_err(&pdev->dev, "cannot get DSI clock\n");
1500 		return PTR_ERR(dsi->clk);
1501 	}
1502 
1503 	dsi->clk_lp = devm_clk_get(&pdev->dev, "lp");
1504 	if (IS_ERR(dsi->clk_lp)) {
1505 		dev_err(&pdev->dev, "cannot get low-power clock\n");
1506 		return PTR_ERR(dsi->clk_lp);
1507 	}
1508 
1509 	dsi->clk_parent = devm_clk_get(&pdev->dev, "parent");
1510 	if (IS_ERR(dsi->clk_parent)) {
1511 		dev_err(&pdev->dev, "cannot get parent clock\n");
1512 		return PTR_ERR(dsi->clk_parent);
1513 	}
1514 
1515 	dsi->vdd = devm_regulator_get(&pdev->dev, "avdd-dsi-csi");
1516 	if (IS_ERR(dsi->vdd)) {
1517 		dev_err(&pdev->dev, "cannot get VDD supply\n");
1518 		return PTR_ERR(dsi->vdd);
1519 	}
1520 
1521 	err = tegra_dsi_setup_clocks(dsi);
1522 	if (err < 0) {
1523 		dev_err(&pdev->dev, "cannot setup clocks\n");
1524 		return err;
1525 	}
1526 
1527 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1528 	dsi->regs = devm_ioremap_resource(&pdev->dev, regs);
1529 	if (IS_ERR(dsi->regs))
1530 		return PTR_ERR(dsi->regs);
1531 
1532 	dsi->mipi = tegra_mipi_request(&pdev->dev);
1533 	if (IS_ERR(dsi->mipi))
1534 		return PTR_ERR(dsi->mipi);
1535 
1536 	dsi->host.ops = &tegra_dsi_host_ops;
1537 	dsi->host.dev = &pdev->dev;
1538 
1539 	err = mipi_dsi_host_register(&dsi->host);
1540 	if (err < 0) {
1541 		dev_err(&pdev->dev, "failed to register DSI host: %d\n", err);
1542 		goto mipi_free;
1543 	}
1544 
1545 	platform_set_drvdata(pdev, dsi);
1546 	pm_runtime_enable(&pdev->dev);
1547 
1548 	INIT_LIST_HEAD(&dsi->client.list);
1549 	dsi->client.ops = &dsi_client_ops;
1550 	dsi->client.dev = &pdev->dev;
1551 
1552 	err = host1x_client_register(&dsi->client);
1553 	if (err < 0) {
1554 		dev_err(&pdev->dev, "failed to register host1x client: %d\n",
1555 			err);
1556 		goto unregister;
1557 	}
1558 
1559 	return 0;
1560 
1561 unregister:
1562 	mipi_dsi_host_unregister(&dsi->host);
1563 mipi_free:
1564 	tegra_mipi_free(dsi->mipi);
1565 	return err;
1566 }
1567 
1568 static int tegra_dsi_remove(struct platform_device *pdev)
1569 {
1570 	struct tegra_dsi *dsi = platform_get_drvdata(pdev);
1571 	int err;
1572 
1573 	pm_runtime_disable(&pdev->dev);
1574 
1575 	err = host1x_client_unregister(&dsi->client);
1576 	if (err < 0) {
1577 		dev_err(&pdev->dev, "failed to unregister host1x client: %d\n",
1578 			err);
1579 		return err;
1580 	}
1581 
1582 	tegra_output_remove(&dsi->output);
1583 
1584 	mipi_dsi_host_unregister(&dsi->host);
1585 	tegra_mipi_free(dsi->mipi);
1586 
1587 	return 0;
1588 }
1589 
1590 #ifdef CONFIG_PM
1591 static int tegra_dsi_suspend(struct device *dev)
1592 {
1593 	struct tegra_dsi *dsi = dev_get_drvdata(dev);
1594 	int err;
1595 
1596 	if (dsi->rst) {
1597 		err = reset_control_assert(dsi->rst);
1598 		if (err < 0) {
1599 			dev_err(dev, "failed to assert reset: %d\n", err);
1600 			return err;
1601 		}
1602 	}
1603 
1604 	usleep_range(1000, 2000);
1605 
1606 	clk_disable_unprepare(dsi->clk_lp);
1607 	clk_disable_unprepare(dsi->clk);
1608 
1609 	regulator_disable(dsi->vdd);
1610 
1611 	return 0;
1612 }
1613 
1614 static int tegra_dsi_resume(struct device *dev)
1615 {
1616 	struct tegra_dsi *dsi = dev_get_drvdata(dev);
1617 	int err;
1618 
1619 	err = regulator_enable(dsi->vdd);
1620 	if (err < 0) {
1621 		dev_err(dsi->dev, "failed to enable VDD supply: %d\n", err);
1622 		return err;
1623 	}
1624 
1625 	err = clk_prepare_enable(dsi->clk);
1626 	if (err < 0) {
1627 		dev_err(dev, "cannot enable DSI clock: %d\n", err);
1628 		goto disable_vdd;
1629 	}
1630 
1631 	err = clk_prepare_enable(dsi->clk_lp);
1632 	if (err < 0) {
1633 		dev_err(dev, "cannot enable low-power clock: %d\n", err);
1634 		goto disable_clk;
1635 	}
1636 
1637 	usleep_range(1000, 2000);
1638 
1639 	if (dsi->rst) {
1640 		err = reset_control_deassert(dsi->rst);
1641 		if (err < 0) {
1642 			dev_err(dev, "cannot assert reset: %d\n", err);
1643 			goto disable_clk_lp;
1644 		}
1645 	}
1646 
1647 	return 0;
1648 
1649 disable_clk_lp:
1650 	clk_disable_unprepare(dsi->clk_lp);
1651 disable_clk:
1652 	clk_disable_unprepare(dsi->clk);
1653 disable_vdd:
1654 	regulator_disable(dsi->vdd);
1655 	return err;
1656 }
1657 #endif
1658 
1659 static const struct dev_pm_ops tegra_dsi_pm_ops = {
1660 	SET_RUNTIME_PM_OPS(tegra_dsi_suspend, tegra_dsi_resume, NULL)
1661 };
1662 
1663 static const struct of_device_id tegra_dsi_of_match[] = {
1664 	{ .compatible = "nvidia,tegra210-dsi", },
1665 	{ .compatible = "nvidia,tegra132-dsi", },
1666 	{ .compatible = "nvidia,tegra124-dsi", },
1667 	{ .compatible = "nvidia,tegra114-dsi", },
1668 	{ },
1669 };
1670 MODULE_DEVICE_TABLE(of, tegra_dsi_of_match);
1671 
1672 struct platform_driver tegra_dsi_driver = {
1673 	.driver = {
1674 		.name = "tegra-dsi",
1675 		.of_match_table = tegra_dsi_of_match,
1676 		.pm = &tegra_dsi_pm_ops,
1677 	},
1678 	.probe = tegra_dsi_probe,
1679 	.remove = tegra_dsi_remove,
1680 };
1681