1 /*
2  * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
3  * Copyright (C) STMicroelectronics SA 2017
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * Modified by Philippe Cornu <philippe.cornu@st.com>
11  * This generic Synopsys DesignWare MIPI DSI host driver is based on the
12  * Rockchip version from rockchip/dw-mipi-dsi.c with phy & bridge APIs.
13  */
14 
15 #include <linux/clk.h>
16 #include <linux/component.h>
17 #include <linux/iopoll.h>
18 #include <linux/module.h>
19 #include <linux/of_device.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/reset.h>
22 #include <drm/drmP.h>
23 #include <drm/drm_atomic_helper.h>
24 #include <drm/drm_bridge.h>
25 #include <drm/drm_crtc.h>
26 #include <drm/drm_crtc_helper.h>
27 #include <drm/drm_mipi_dsi.h>
28 #include <drm/drm_of.h>
29 #include <drm/bridge/dw_mipi_dsi.h>
30 #include <video/mipi_display.h>
31 
32 #define DSI_VERSION			0x00
33 
34 #define DSI_PWR_UP			0x04
35 #define RESET				0
36 #define POWERUP				BIT(0)
37 
38 #define DSI_CLKMGR_CFG			0x08
39 #define TO_CLK_DIVISION(div)		(((div) & 0xff) << 8)
40 #define TX_ESC_CLK_DIVISION(div)	((div) & 0xff)
41 
42 #define DSI_DPI_VCID			0x0c
43 #define DPI_VCID(vcid)			((vcid) & 0x3)
44 
45 #define DSI_DPI_COLOR_CODING		0x10
46 #define LOOSELY18_EN			BIT(8)
47 #define DPI_COLOR_CODING_16BIT_1	0x0
48 #define DPI_COLOR_CODING_16BIT_2	0x1
49 #define DPI_COLOR_CODING_16BIT_3	0x2
50 #define DPI_COLOR_CODING_18BIT_1	0x3
51 #define DPI_COLOR_CODING_18BIT_2	0x4
52 #define DPI_COLOR_CODING_24BIT		0x5
53 
54 #define DSI_DPI_CFG_POL			0x14
55 #define COLORM_ACTIVE_LOW		BIT(4)
56 #define SHUTD_ACTIVE_LOW		BIT(3)
57 #define HSYNC_ACTIVE_LOW		BIT(2)
58 #define VSYNC_ACTIVE_LOW		BIT(1)
59 #define DATAEN_ACTIVE_LOW		BIT(0)
60 
61 #define DSI_DPI_LP_CMD_TIM		0x18
62 #define OUTVACT_LPCMD_TIME(p)		(((p) & 0xff) << 16)
63 #define INVACT_LPCMD_TIME(p)		((p) & 0xff)
64 
65 #define DSI_DBI_VCID			0x1c
66 #define DSI_DBI_CFG			0x20
67 #define DSI_DBI_PARTITIONING_EN		0x24
68 #define DSI_DBI_CMDSIZE			0x28
69 
70 #define DSI_PCKHDL_CFG			0x2c
71 #define CRC_RX_EN			BIT(4)
72 #define ECC_RX_EN			BIT(3)
73 #define BTA_EN				BIT(2)
74 #define EOTP_RX_EN			BIT(1)
75 #define EOTP_TX_EN			BIT(0)
76 
77 #define DSI_GEN_VCID			0x30
78 
79 #define DSI_MODE_CFG			0x34
80 #define ENABLE_VIDEO_MODE		0
81 #define ENABLE_CMD_MODE			BIT(0)
82 
83 #define DSI_VID_MODE_CFG		0x38
84 #define ENABLE_LOW_POWER		(0x3f << 8)
85 #define ENABLE_LOW_POWER_MASK		(0x3f << 8)
86 #define VID_MODE_TYPE_NON_BURST_SYNC_PULSES	0x0
87 #define VID_MODE_TYPE_NON_BURST_SYNC_EVENTS	0x1
88 #define VID_MODE_TYPE_BURST			0x2
89 #define VID_MODE_TYPE_MASK			0x3
90 
91 #define DSI_VID_PKT_SIZE		0x3c
92 #define VID_PKT_SIZE(p)			((p) & 0x3fff)
93 
94 #define DSI_VID_NUM_CHUNKS		0x40
95 #define VID_NUM_CHUNKS(c)		((c) & 0x1fff)
96 
97 #define DSI_VID_NULL_SIZE		0x44
98 #define VID_NULL_SIZE(b)		((b) & 0x1fff)
99 
100 #define DSI_VID_HSA_TIME		0x48
101 #define DSI_VID_HBP_TIME		0x4c
102 #define DSI_VID_HLINE_TIME		0x50
103 #define DSI_VID_VSA_LINES		0x54
104 #define DSI_VID_VBP_LINES		0x58
105 #define DSI_VID_VFP_LINES		0x5c
106 #define DSI_VID_VACTIVE_LINES		0x60
107 #define DSI_EDPI_CMD_SIZE		0x64
108 
109 #define DSI_CMD_MODE_CFG		0x68
110 #define MAX_RD_PKT_SIZE_LP		BIT(24)
111 #define DCS_LW_TX_LP			BIT(19)
112 #define DCS_SR_0P_TX_LP			BIT(18)
113 #define DCS_SW_1P_TX_LP			BIT(17)
114 #define DCS_SW_0P_TX_LP			BIT(16)
115 #define GEN_LW_TX_LP			BIT(14)
116 #define GEN_SR_2P_TX_LP			BIT(13)
117 #define GEN_SR_1P_TX_LP			BIT(12)
118 #define GEN_SR_0P_TX_LP			BIT(11)
119 #define GEN_SW_2P_TX_LP			BIT(10)
120 #define GEN_SW_1P_TX_LP			BIT(9)
121 #define GEN_SW_0P_TX_LP			BIT(8)
122 #define ACK_RQST_EN			BIT(1)
123 #define TEAR_FX_EN			BIT(0)
124 
125 #define CMD_MODE_ALL_LP			(MAX_RD_PKT_SIZE_LP | \
126 					 DCS_LW_TX_LP | \
127 					 DCS_SR_0P_TX_LP | \
128 					 DCS_SW_1P_TX_LP | \
129 					 DCS_SW_0P_TX_LP | \
130 					 GEN_LW_TX_LP | \
131 					 GEN_SR_2P_TX_LP | \
132 					 GEN_SR_1P_TX_LP | \
133 					 GEN_SR_0P_TX_LP | \
134 					 GEN_SW_2P_TX_LP | \
135 					 GEN_SW_1P_TX_LP | \
136 					 GEN_SW_0P_TX_LP)
137 
138 #define DSI_GEN_HDR			0x6c
139 /* TODO These 2 defines will be reworked thanks to mipi_dsi_create_packet() */
140 #define GEN_HDATA(data)			(((data) & 0xffff) << 8)
141 #define GEN_HTYPE(type)			(((type) & 0xff) << 0)
142 
143 #define DSI_GEN_PLD_DATA		0x70
144 
145 #define DSI_CMD_PKT_STATUS		0x74
146 #define GEN_RD_CMD_BUSY			BIT(6)
147 #define GEN_PLD_R_FULL			BIT(5)
148 #define GEN_PLD_R_EMPTY			BIT(4)
149 #define GEN_PLD_W_FULL			BIT(3)
150 #define GEN_PLD_W_EMPTY			BIT(2)
151 #define GEN_CMD_FULL			BIT(1)
152 #define GEN_CMD_EMPTY			BIT(0)
153 
154 #define DSI_TO_CNT_CFG			0x78
155 #define HSTX_TO_CNT(p)			(((p) & 0xffff) << 16)
156 #define LPRX_TO_CNT(p)			((p) & 0xffff)
157 
158 #define DSI_HS_RD_TO_CNT		0x7c
159 #define DSI_LP_RD_TO_CNT		0x80
160 #define DSI_HS_WR_TO_CNT		0x84
161 #define DSI_LP_WR_TO_CNT		0x88
162 #define DSI_BTA_TO_CNT			0x8c
163 
164 #define DSI_LPCLK_CTRL			0x94
165 #define AUTO_CLKLANE_CTRL		BIT(1)
166 #define PHY_TXREQUESTCLKHS		BIT(0)
167 
168 #define DSI_PHY_TMR_LPCLK_CFG		0x98
169 #define PHY_CLKHS2LP_TIME(lbcc)		(((lbcc) & 0x3ff) << 16)
170 #define PHY_CLKLP2HS_TIME(lbcc)		((lbcc) & 0x3ff)
171 
172 /* TODO Next register is slightly different between 1.30 & 1.31 IP version */
173 #define DSI_PHY_TMR_CFG			0x9c
174 #define PHY_HS2LP_TIME(lbcc)		(((lbcc) & 0xff) << 24)
175 #define PHY_LP2HS_TIME(lbcc)		(((lbcc) & 0xff) << 16)
176 #define MAX_RD_TIME(lbcc)		((lbcc) & 0x7fff)
177 
178 #define DSI_PHY_RSTZ			0xa0
179 #define PHY_DISFORCEPLL			0
180 #define PHY_ENFORCEPLL			BIT(3)
181 #define PHY_DISABLECLK			0
182 #define PHY_ENABLECLK			BIT(2)
183 #define PHY_RSTZ			0
184 #define PHY_UNRSTZ			BIT(1)
185 #define PHY_SHUTDOWNZ			0
186 #define PHY_UNSHUTDOWNZ			BIT(0)
187 
188 #define DSI_PHY_IF_CFG			0xa4
189 #define PHY_STOP_WAIT_TIME(cycle)	(((cycle) & 0xff) << 8)
190 #define N_LANES(n)			(((n) - 1) & 0x3)
191 
192 #define DSI_PHY_ULPS_CTRL		0xa8
193 #define DSI_PHY_TX_TRIGGERS		0xac
194 
195 #define DSI_PHY_STATUS			0xb0
196 #define PHY_STOP_STATE_CLK_LANE		BIT(2)
197 #define PHY_LOCK			BIT(0)
198 
199 #define DSI_PHY_TST_CTRL0		0xb4
200 #define PHY_TESTCLK			BIT(1)
201 #define PHY_UNTESTCLK			0
202 #define PHY_TESTCLR			BIT(0)
203 #define PHY_UNTESTCLR			0
204 
205 #define DSI_PHY_TST_CTRL1		0xb8
206 #define PHY_TESTEN			BIT(16)
207 #define PHY_UNTESTEN			0
208 #define PHY_TESTDOUT(n)			(((n) & 0xff) << 8)
209 #define PHY_TESTDIN(n)			((n) & 0xff)
210 
211 #define DSI_INT_ST0			0xbc
212 #define DSI_INT_ST1			0xc0
213 #define DSI_INT_MSK0			0xc4
214 #define DSI_INT_MSK1			0xc8
215 #define DSI_PHY_TMR_RD_CFG		0xf4
216 
217 #define PHY_STATUS_TIMEOUT_US		10000
218 #define CMD_PKT_STATUS_TIMEOUT_US	20000
219 
220 struct dw_mipi_dsi {
221 	struct drm_bridge bridge;
222 	struct mipi_dsi_host dsi_host;
223 	struct drm_bridge *panel_bridge;
224 	struct device *dev;
225 	void __iomem *base;
226 
227 	struct clk *pclk;
228 
229 	unsigned int lane_mbps; /* per lane */
230 	u32 channel;
231 	u32 lanes;
232 	u32 format;
233 	unsigned long mode_flags;
234 
235 	const struct dw_mipi_dsi_plat_data *plat_data;
236 };
237 
238 /*
239  * The controller should generate 2 frames before
240  * preparing the peripheral.
241  */
242 static void dw_mipi_dsi_wait_for_two_frames(struct drm_display_mode *mode)
243 {
244 	int refresh, two_frames;
245 
246 	refresh = drm_mode_vrefresh(mode);
247 	two_frames = DIV_ROUND_UP(MSEC_PER_SEC, refresh) * 2;
248 	msleep(two_frames);
249 }
250 
251 static inline struct dw_mipi_dsi *host_to_dsi(struct mipi_dsi_host *host)
252 {
253 	return container_of(host, struct dw_mipi_dsi, dsi_host);
254 }
255 
256 static inline struct dw_mipi_dsi *bridge_to_dsi(struct drm_bridge *bridge)
257 {
258 	return container_of(bridge, struct dw_mipi_dsi, bridge);
259 }
260 
261 static inline void dsi_write(struct dw_mipi_dsi *dsi, u32 reg, u32 val)
262 {
263 	writel(val, dsi->base + reg);
264 }
265 
266 static inline u32 dsi_read(struct dw_mipi_dsi *dsi, u32 reg)
267 {
268 	return readl(dsi->base + reg);
269 }
270 
271 static int dw_mipi_dsi_host_attach(struct mipi_dsi_host *host,
272 				   struct mipi_dsi_device *device)
273 {
274 	struct dw_mipi_dsi *dsi = host_to_dsi(host);
275 	struct drm_bridge *bridge;
276 	struct drm_panel *panel;
277 	int ret;
278 
279 	if (device->lanes > dsi->plat_data->max_data_lanes) {
280 		dev_err(dsi->dev, "the number of data lanes(%u) is too many\n",
281 			device->lanes);
282 		return -EINVAL;
283 	}
284 
285 	dsi->lanes = device->lanes;
286 	dsi->channel = device->channel;
287 	dsi->format = device->format;
288 	dsi->mode_flags = device->mode_flags;
289 
290 	ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0,
291 					  &panel, &bridge);
292 	if (ret)
293 		return ret;
294 
295 	if (panel) {
296 		bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DSI);
297 		if (IS_ERR(bridge))
298 			return PTR_ERR(bridge);
299 	}
300 
301 	dsi->panel_bridge = bridge;
302 
303 	drm_bridge_add(&dsi->bridge);
304 
305 	return 0;
306 }
307 
308 static int dw_mipi_dsi_host_detach(struct mipi_dsi_host *host,
309 				   struct mipi_dsi_device *device)
310 {
311 	struct dw_mipi_dsi *dsi = host_to_dsi(host);
312 
313 	drm_of_panel_bridge_remove(host->dev->of_node, 1, 0);
314 
315 	drm_bridge_remove(&dsi->bridge);
316 
317 	return 0;
318 }
319 
320 static void dw_mipi_message_config(struct dw_mipi_dsi *dsi,
321 				   const struct mipi_dsi_msg *msg)
322 {
323 	bool lpm = msg->flags & MIPI_DSI_MSG_USE_LPM;
324 	u32 val = 0;
325 
326 	if (msg->flags & MIPI_DSI_MSG_REQ_ACK)
327 		val |= ACK_RQST_EN;
328 	if (lpm)
329 		val |= CMD_MODE_ALL_LP;
330 
331 	dsi_write(dsi, DSI_LPCLK_CTRL, lpm ? 0 : PHY_TXREQUESTCLKHS);
332 	dsi_write(dsi, DSI_CMD_MODE_CFG, val);
333 }
334 
335 static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
336 {
337 	int ret;
338 	u32 val, mask;
339 
340 	ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
341 				 val, !(val & GEN_CMD_FULL), 1000,
342 				 CMD_PKT_STATUS_TIMEOUT_US);
343 	if (ret < 0) {
344 		dev_err(dsi->dev, "failed to get available command FIFO\n");
345 		return ret;
346 	}
347 
348 	dsi_write(dsi, DSI_GEN_HDR, hdr_val);
349 
350 	mask = GEN_CMD_EMPTY | GEN_PLD_W_EMPTY;
351 	ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
352 				 val, (val & mask) == mask,
353 				 1000, CMD_PKT_STATUS_TIMEOUT_US);
354 	if (ret < 0) {
355 		dev_err(dsi->dev, "failed to write command FIFO\n");
356 		return ret;
357 	}
358 
359 	return 0;
360 }
361 
362 static int dw_mipi_dsi_dcs_short_write(struct dw_mipi_dsi *dsi,
363 				       const struct mipi_dsi_msg *msg)
364 {
365 	const u8 *tx_buf = msg->tx_buf;
366 	u16 data = 0;
367 	u32 val;
368 
369 	if (msg->tx_len > 0)
370 		data |= tx_buf[0];
371 	if (msg->tx_len > 1)
372 		data |= tx_buf[1] << 8;
373 
374 	if (msg->tx_len > 2) {
375 		dev_err(dsi->dev, "too long tx buf length %zu for short write\n",
376 			msg->tx_len);
377 		return -EINVAL;
378 	}
379 
380 	val = GEN_HDATA(data) | GEN_HTYPE(msg->type);
381 	return dw_mipi_dsi_gen_pkt_hdr_write(dsi, val);
382 }
383 
384 static int dw_mipi_dsi_dcs_long_write(struct dw_mipi_dsi *dsi,
385 				      const struct mipi_dsi_msg *msg)
386 {
387 	const u8 *tx_buf = msg->tx_buf;
388 	int len = msg->tx_len, pld_data_bytes = sizeof(u32), ret;
389 	u32 hdr_val = GEN_HDATA(msg->tx_len) | GEN_HTYPE(msg->type);
390 	u32 remainder;
391 	u32 val;
392 
393 	if (msg->tx_len < 3) {
394 		dev_err(dsi->dev, "wrong tx buf length %zu for long write\n",
395 			msg->tx_len);
396 		return -EINVAL;
397 	}
398 
399 	while (DIV_ROUND_UP(len, pld_data_bytes)) {
400 		if (len < pld_data_bytes) {
401 			remainder = 0;
402 			memcpy(&remainder, tx_buf, len);
403 			dsi_write(dsi, DSI_GEN_PLD_DATA, remainder);
404 			len = 0;
405 		} else {
406 			memcpy(&remainder, tx_buf, pld_data_bytes);
407 			dsi_write(dsi, DSI_GEN_PLD_DATA, remainder);
408 			tx_buf += pld_data_bytes;
409 			len -= pld_data_bytes;
410 		}
411 
412 		ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
413 					 val, !(val & GEN_PLD_W_FULL), 1000,
414 					 CMD_PKT_STATUS_TIMEOUT_US);
415 		if (ret < 0) {
416 			dev_err(dsi->dev,
417 				"failed to get available write payload FIFO\n");
418 			return ret;
419 		}
420 	}
421 
422 	return dw_mipi_dsi_gen_pkt_hdr_write(dsi, hdr_val);
423 }
424 
425 static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
426 					 const struct mipi_dsi_msg *msg)
427 {
428 	struct dw_mipi_dsi *dsi = host_to_dsi(host);
429 	int ret;
430 
431 	/*
432 	 * TODO dw drv improvements
433 	 * use mipi_dsi_create_packet() instead of all following
434 	 * functions and code (no switch cases, no
435 	 * dw_mipi_dsi_dcs_short_write(), only the loop in long_write...)
436 	 * and use packet.header...
437 	 */
438 	dw_mipi_message_config(dsi, msg);
439 
440 	switch (msg->type) {
441 	case MIPI_DSI_DCS_SHORT_WRITE:
442 	case MIPI_DSI_DCS_SHORT_WRITE_PARAM:
443 	case MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE:
444 		ret = dw_mipi_dsi_dcs_short_write(dsi, msg);
445 		break;
446 	case MIPI_DSI_DCS_LONG_WRITE:
447 		ret = dw_mipi_dsi_dcs_long_write(dsi, msg);
448 		break;
449 	default:
450 		dev_err(dsi->dev, "unsupported message type 0x%02x\n",
451 			msg->type);
452 		ret = -EINVAL;
453 	}
454 
455 	return ret;
456 }
457 
458 static const struct mipi_dsi_host_ops dw_mipi_dsi_host_ops = {
459 	.attach = dw_mipi_dsi_host_attach,
460 	.detach = dw_mipi_dsi_host_detach,
461 	.transfer = dw_mipi_dsi_host_transfer,
462 };
463 
464 static void dw_mipi_dsi_video_mode_config(struct dw_mipi_dsi *dsi)
465 {
466 	u32 val;
467 
468 	/*
469 	 * TODO dw drv improvements
470 	 * enabling low power is panel-dependent, we should use the
471 	 * panel configuration here...
472 	 */
473 	val = ENABLE_LOW_POWER;
474 
475 	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
476 		val |= VID_MODE_TYPE_BURST;
477 	else if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
478 		val |= VID_MODE_TYPE_NON_BURST_SYNC_PULSES;
479 	else
480 		val |= VID_MODE_TYPE_NON_BURST_SYNC_EVENTS;
481 
482 	dsi_write(dsi, DSI_VID_MODE_CFG, val);
483 }
484 
485 static void dw_mipi_dsi_set_mode(struct dw_mipi_dsi *dsi,
486 				 unsigned long mode_flags)
487 {
488 	dsi_write(dsi, DSI_PWR_UP, RESET);
489 
490 	if (mode_flags & MIPI_DSI_MODE_VIDEO) {
491 		dsi_write(dsi, DSI_MODE_CFG, ENABLE_VIDEO_MODE);
492 		dw_mipi_dsi_video_mode_config(dsi);
493 		dsi_write(dsi, DSI_LPCLK_CTRL, PHY_TXREQUESTCLKHS);
494 	} else {
495 		dsi_write(dsi, DSI_MODE_CFG, ENABLE_CMD_MODE);
496 	}
497 
498 	dsi_write(dsi, DSI_PWR_UP, POWERUP);
499 }
500 
501 static void dw_mipi_dsi_disable(struct dw_mipi_dsi *dsi)
502 {
503 	dsi_write(dsi, DSI_PWR_UP, RESET);
504 	dsi_write(dsi, DSI_PHY_RSTZ, PHY_RSTZ);
505 }
506 
507 static void dw_mipi_dsi_init(struct dw_mipi_dsi *dsi)
508 {
509 	/*
510 	 * The maximum permitted escape clock is 20MHz and it is derived from
511 	 * lanebyteclk, which is running at "lane_mbps / 8".  Thus we want:
512 	 *
513 	 *     (lane_mbps >> 3) / esc_clk_division < 20
514 	 * which is:
515 	 *     (lane_mbps >> 3) / 20 > esc_clk_division
516 	 */
517 	u32 esc_clk_division = (dsi->lane_mbps >> 3) / 20 + 1;
518 
519 	dsi_write(dsi, DSI_PWR_UP, RESET);
520 
521 	/*
522 	 * TODO dw drv improvements
523 	 * timeout clock division should be computed with the
524 	 * high speed transmission counter timeout and byte lane...
525 	 */
526 	dsi_write(dsi, DSI_CLKMGR_CFG, TO_CLK_DIVISION(10) |
527 		  TX_ESC_CLK_DIVISION(esc_clk_division));
528 }
529 
530 static void dw_mipi_dsi_dpi_config(struct dw_mipi_dsi *dsi,
531 				   struct drm_display_mode *mode)
532 {
533 	u32 val = 0, color = 0;
534 
535 	switch (dsi->format) {
536 	case MIPI_DSI_FMT_RGB888:
537 		color = DPI_COLOR_CODING_24BIT;
538 		break;
539 	case MIPI_DSI_FMT_RGB666:
540 		color = DPI_COLOR_CODING_18BIT_2 | LOOSELY18_EN;
541 		break;
542 	case MIPI_DSI_FMT_RGB666_PACKED:
543 		color = DPI_COLOR_CODING_18BIT_1;
544 		break;
545 	case MIPI_DSI_FMT_RGB565:
546 		color = DPI_COLOR_CODING_16BIT_1;
547 		break;
548 	}
549 
550 	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
551 		val |= VSYNC_ACTIVE_LOW;
552 	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
553 		val |= HSYNC_ACTIVE_LOW;
554 
555 	dsi_write(dsi, DSI_DPI_VCID, DPI_VCID(dsi->channel));
556 	dsi_write(dsi, DSI_DPI_COLOR_CODING, color);
557 	dsi_write(dsi, DSI_DPI_CFG_POL, val);
558 	/*
559 	 * TODO dw drv improvements
560 	 * largest packet sizes during hfp or during vsa/vpb/vfp
561 	 * should be computed according to byte lane, lane number and only
562 	 * if sending lp cmds in high speed is enable (PHY_TXREQUESTCLKHS)
563 	 */
564 	dsi_write(dsi, DSI_DPI_LP_CMD_TIM, OUTVACT_LPCMD_TIME(4)
565 		  | INVACT_LPCMD_TIME(4));
566 }
567 
568 static void dw_mipi_dsi_packet_handler_config(struct dw_mipi_dsi *dsi)
569 {
570 	dsi_write(dsi, DSI_PCKHDL_CFG, CRC_RX_EN | ECC_RX_EN | BTA_EN);
571 }
572 
573 static void dw_mipi_dsi_video_packet_config(struct dw_mipi_dsi *dsi,
574 					    struct drm_display_mode *mode)
575 {
576 	/*
577 	 * TODO dw drv improvements
578 	 * only burst mode is supported here. For non-burst video modes,
579 	 * we should compute DSI_VID_PKT_SIZE, DSI_VCCR.NUMC &
580 	 * DSI_VNPCR.NPSIZE... especially because this driver supports
581 	 * non-burst video modes, see dw_mipi_dsi_video_mode_config()...
582 	 */
583 	dsi_write(dsi, DSI_VID_PKT_SIZE, VID_PKT_SIZE(mode->hdisplay));
584 }
585 
586 static void dw_mipi_dsi_command_mode_config(struct dw_mipi_dsi *dsi)
587 {
588 	/*
589 	 * TODO dw drv improvements
590 	 * compute high speed transmission counter timeout according
591 	 * to the timeout clock division (TO_CLK_DIVISION) and byte lane...
592 	 */
593 	dsi_write(dsi, DSI_TO_CNT_CFG, HSTX_TO_CNT(1000) | LPRX_TO_CNT(1000));
594 	/*
595 	 * TODO dw drv improvements
596 	 * the Bus-Turn-Around Timeout Counter should be computed
597 	 * according to byte lane...
598 	 */
599 	dsi_write(dsi, DSI_BTA_TO_CNT, 0xd00);
600 	dsi_write(dsi, DSI_MODE_CFG, ENABLE_CMD_MODE);
601 }
602 
603 /* Get lane byte clock cycles. */
604 static u32 dw_mipi_dsi_get_hcomponent_lbcc(struct dw_mipi_dsi *dsi,
605 					   struct drm_display_mode *mode,
606 					   u32 hcomponent)
607 {
608 	u32 frac, lbcc;
609 
610 	lbcc = hcomponent * dsi->lane_mbps * MSEC_PER_SEC / 8;
611 
612 	frac = lbcc % mode->clock;
613 	lbcc = lbcc / mode->clock;
614 	if (frac)
615 		lbcc++;
616 
617 	return lbcc;
618 }
619 
620 static void dw_mipi_dsi_line_timer_config(struct dw_mipi_dsi *dsi,
621 					  struct drm_display_mode *mode)
622 {
623 	u32 htotal, hsa, hbp, lbcc;
624 
625 	htotal = mode->htotal;
626 	hsa = mode->hsync_end - mode->hsync_start;
627 	hbp = mode->htotal - mode->hsync_end;
628 
629 	/*
630 	 * TODO dw drv improvements
631 	 * computations below may be improved...
632 	 */
633 	lbcc = dw_mipi_dsi_get_hcomponent_lbcc(dsi, mode, htotal);
634 	dsi_write(dsi, DSI_VID_HLINE_TIME, lbcc);
635 
636 	lbcc = dw_mipi_dsi_get_hcomponent_lbcc(dsi, mode, hsa);
637 	dsi_write(dsi, DSI_VID_HSA_TIME, lbcc);
638 
639 	lbcc = dw_mipi_dsi_get_hcomponent_lbcc(dsi, mode, hbp);
640 	dsi_write(dsi, DSI_VID_HBP_TIME, lbcc);
641 }
642 
643 static void dw_mipi_dsi_vertical_timing_config(struct dw_mipi_dsi *dsi,
644 					       struct drm_display_mode *mode)
645 {
646 	u32 vactive, vsa, vfp, vbp;
647 
648 	vactive = mode->vdisplay;
649 	vsa = mode->vsync_end - mode->vsync_start;
650 	vfp = mode->vsync_start - mode->vdisplay;
651 	vbp = mode->vtotal - mode->vsync_end;
652 
653 	dsi_write(dsi, DSI_VID_VACTIVE_LINES, vactive);
654 	dsi_write(dsi, DSI_VID_VSA_LINES, vsa);
655 	dsi_write(dsi, DSI_VID_VFP_LINES, vfp);
656 	dsi_write(dsi, DSI_VID_VBP_LINES, vbp);
657 }
658 
659 static void dw_mipi_dsi_dphy_timing_config(struct dw_mipi_dsi *dsi)
660 {
661 	/*
662 	 * TODO dw drv improvements
663 	 * data & clock lane timers should be computed according to panel
664 	 * blankings and to the automatic clock lane control mode...
665 	 * note: DSI_PHY_TMR_CFG.MAX_RD_TIME should be in line with
666 	 * DSI_CMD_MODE_CFG.MAX_RD_PKT_SIZE_LP (see CMD_MODE_ALL_LP)
667 	 */
668 	dsi_write(dsi, DSI_PHY_TMR_CFG, PHY_HS2LP_TIME(0x40)
669 		  | PHY_LP2HS_TIME(0x40) | MAX_RD_TIME(10000));
670 
671 	dsi_write(dsi, DSI_PHY_TMR_LPCLK_CFG, PHY_CLKHS2LP_TIME(0x40)
672 		  | PHY_CLKLP2HS_TIME(0x40));
673 }
674 
675 static void dw_mipi_dsi_dphy_interface_config(struct dw_mipi_dsi *dsi)
676 {
677 	/*
678 	 * TODO dw drv improvements
679 	 * stop wait time should be the maximum between host dsi
680 	 * and panel stop wait times
681 	 */
682 	dsi_write(dsi, DSI_PHY_IF_CFG, PHY_STOP_WAIT_TIME(0x20) |
683 		  N_LANES(dsi->lanes));
684 }
685 
686 static void dw_mipi_dsi_dphy_init(struct dw_mipi_dsi *dsi)
687 {
688 	/* Clear PHY state */
689 	dsi_write(dsi, DSI_PHY_RSTZ, PHY_DISFORCEPLL | PHY_DISABLECLK
690 		  | PHY_RSTZ | PHY_SHUTDOWNZ);
691 	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLR);
692 	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLR);
693 	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLR);
694 }
695 
696 static void dw_mipi_dsi_dphy_enable(struct dw_mipi_dsi *dsi)
697 {
698 	u32 val;
699 	int ret;
700 
701 	dsi_write(dsi, DSI_PHY_RSTZ, PHY_ENFORCEPLL | PHY_ENABLECLK |
702 		  PHY_UNRSTZ | PHY_UNSHUTDOWNZ);
703 
704 	ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS, val,
705 				 val & PHY_LOCK, 1000, PHY_STATUS_TIMEOUT_US);
706 	if (ret < 0)
707 		DRM_DEBUG_DRIVER("failed to wait phy lock state\n");
708 
709 	ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS,
710 				 val, val & PHY_STOP_STATE_CLK_LANE, 1000,
711 				 PHY_STATUS_TIMEOUT_US);
712 	if (ret < 0)
713 		DRM_DEBUG_DRIVER("failed to wait phy clk lane stop state\n");
714 }
715 
716 static void dw_mipi_dsi_clear_err(struct dw_mipi_dsi *dsi)
717 {
718 	dsi_read(dsi, DSI_INT_ST0);
719 	dsi_read(dsi, DSI_INT_ST1);
720 	dsi_write(dsi, DSI_INT_MSK0, 0);
721 	dsi_write(dsi, DSI_INT_MSK1, 0);
722 }
723 
724 static void dw_mipi_dsi_bridge_post_disable(struct drm_bridge *bridge)
725 {
726 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
727 
728 	/*
729 	 * Switch to command mode before panel-bridge post_disable &
730 	 * panel unprepare.
731 	 * Note: panel-bridge disable & panel disable has been called
732 	 * before by the drm framework.
733 	 */
734 	dw_mipi_dsi_set_mode(dsi, 0);
735 
736 	/*
737 	 * TODO Only way found to call panel-bridge post_disable &
738 	 * panel unprepare before the dsi "final" disable...
739 	 * This needs to be fixed in the drm_bridge framework and the API
740 	 * needs to be updated to manage our own call chains...
741 	 */
742 	dsi->panel_bridge->funcs->post_disable(dsi->panel_bridge);
743 
744 	dw_mipi_dsi_disable(dsi);
745 	clk_disable_unprepare(dsi->pclk);
746 	pm_runtime_put(dsi->dev);
747 }
748 
749 void dw_mipi_dsi_bridge_mode_set(struct drm_bridge *bridge,
750 				 struct drm_display_mode *mode,
751 				 struct drm_display_mode *adjusted_mode)
752 {
753 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
754 	const struct dw_mipi_dsi_phy_ops *phy_ops = dsi->plat_data->phy_ops;
755 	void *priv_data = dsi->plat_data->priv_data;
756 	int ret;
757 
758 	clk_prepare_enable(dsi->pclk);
759 
760 	ret = phy_ops->get_lane_mbps(priv_data, mode, dsi->mode_flags,
761 				     dsi->lanes, dsi->format, &dsi->lane_mbps);
762 	if (ret)
763 		DRM_DEBUG_DRIVER("Phy get_lane_mbps() failed\n");
764 
765 	pm_runtime_get_sync(dsi->dev);
766 	dw_mipi_dsi_init(dsi);
767 	dw_mipi_dsi_dpi_config(dsi, mode);
768 	dw_mipi_dsi_packet_handler_config(dsi);
769 	dw_mipi_dsi_video_mode_config(dsi);
770 	dw_mipi_dsi_video_packet_config(dsi, mode);
771 	dw_mipi_dsi_command_mode_config(dsi);
772 	dw_mipi_dsi_line_timer_config(dsi, mode);
773 	dw_mipi_dsi_vertical_timing_config(dsi, mode);
774 
775 	dw_mipi_dsi_dphy_init(dsi);
776 	dw_mipi_dsi_dphy_timing_config(dsi);
777 	dw_mipi_dsi_dphy_interface_config(dsi);
778 
779 	dw_mipi_dsi_clear_err(dsi);
780 
781 	ret = phy_ops->init(priv_data);
782 	if (ret)
783 		DRM_DEBUG_DRIVER("Phy init() failed\n");
784 
785 	dw_mipi_dsi_dphy_enable(dsi);
786 
787 	dw_mipi_dsi_wait_for_two_frames(mode);
788 
789 	/* Switch to cmd mode for panel-bridge pre_enable & panel prepare */
790 	dw_mipi_dsi_set_mode(dsi, 0);
791 }
792 
793 static void dw_mipi_dsi_bridge_enable(struct drm_bridge *bridge)
794 {
795 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
796 
797 	/* Switch to video mode for panel-bridge enable & panel enable */
798 	dw_mipi_dsi_set_mode(dsi, MIPI_DSI_MODE_VIDEO);
799 }
800 
801 static enum drm_mode_status
802 dw_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
803 			      const struct drm_display_mode *mode)
804 {
805 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
806 	const struct dw_mipi_dsi_plat_data *pdata = dsi->plat_data;
807 	enum drm_mode_status mode_status = MODE_OK;
808 
809 	if (pdata->mode_valid)
810 		mode_status = pdata->mode_valid(pdata->priv_data, mode);
811 
812 	return mode_status;
813 }
814 
815 static int dw_mipi_dsi_bridge_attach(struct drm_bridge *bridge)
816 {
817 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
818 
819 	if (!bridge->encoder) {
820 		DRM_ERROR("Parent encoder object not found\n");
821 		return -ENODEV;
822 	}
823 
824 	/* Set the encoder type as caller does not know it */
825 	bridge->encoder->encoder_type = DRM_MODE_ENCODER_DSI;
826 
827 	/* Attach the panel-bridge to the dsi bridge */
828 	return drm_bridge_attach(bridge->encoder, dsi->panel_bridge, bridge);
829 }
830 
831 static const struct drm_bridge_funcs dw_mipi_dsi_bridge_funcs = {
832 	.mode_set     = dw_mipi_dsi_bridge_mode_set,
833 	.enable	      = dw_mipi_dsi_bridge_enable,
834 	.post_disable = dw_mipi_dsi_bridge_post_disable,
835 	.mode_valid   = dw_mipi_dsi_bridge_mode_valid,
836 	.attach	      = dw_mipi_dsi_bridge_attach,
837 };
838 
839 static struct dw_mipi_dsi *
840 __dw_mipi_dsi_probe(struct platform_device *pdev,
841 		    const struct dw_mipi_dsi_plat_data *plat_data)
842 {
843 	struct device *dev = &pdev->dev;
844 	struct reset_control *apb_rst;
845 	struct dw_mipi_dsi *dsi;
846 	struct resource *res;
847 	int ret;
848 
849 	dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
850 	if (!dsi)
851 		return ERR_PTR(-ENOMEM);
852 
853 	dsi->dev = dev;
854 	dsi->plat_data = plat_data;
855 
856 	if (!plat_data->phy_ops->init || !plat_data->phy_ops->get_lane_mbps) {
857 		DRM_ERROR("Phy not properly configured\n");
858 		return ERR_PTR(-ENODEV);
859 	}
860 
861 	if (!plat_data->base) {
862 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
863 		if (!res)
864 			return ERR_PTR(-ENODEV);
865 
866 		dsi->base = devm_ioremap_resource(dev, res);
867 		if (IS_ERR(dsi->base))
868 			return ERR_PTR(-ENODEV);
869 
870 	} else {
871 		dsi->base = plat_data->base;
872 	}
873 
874 	dsi->pclk = devm_clk_get(dev, "pclk");
875 	if (IS_ERR(dsi->pclk)) {
876 		ret = PTR_ERR(dsi->pclk);
877 		dev_err(dev, "Unable to get pclk: %d\n", ret);
878 		return ERR_PTR(ret);
879 	}
880 
881 	/*
882 	 * Note that the reset was not defined in the initial device tree, so
883 	 * we have to be prepared for it not being found.
884 	 */
885 	apb_rst = devm_reset_control_get_optional_exclusive(dev, "apb");
886 	if (IS_ERR(apb_rst)) {
887 		ret = PTR_ERR(apb_rst);
888 
889 		if (ret != -EPROBE_DEFER)
890 			dev_err(dev, "Unable to get reset control: %d\n", ret);
891 
892 		return ERR_PTR(ret);
893 	}
894 
895 	if (apb_rst) {
896 		ret = clk_prepare_enable(dsi->pclk);
897 		if (ret) {
898 			dev_err(dev, "%s: Failed to enable pclk\n", __func__);
899 			return ERR_PTR(ret);
900 		}
901 
902 		reset_control_assert(apb_rst);
903 		usleep_range(10, 20);
904 		reset_control_deassert(apb_rst);
905 
906 		clk_disable_unprepare(dsi->pclk);
907 	}
908 
909 	pm_runtime_enable(dev);
910 
911 	dsi->dsi_host.ops = &dw_mipi_dsi_host_ops;
912 	dsi->dsi_host.dev = dev;
913 	ret = mipi_dsi_host_register(&dsi->dsi_host);
914 	if (ret) {
915 		dev_err(dev, "Failed to register MIPI host: %d\n", ret);
916 		return ERR_PTR(ret);
917 	}
918 
919 	dsi->bridge.driver_private = dsi;
920 	dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
921 #ifdef CONFIG_OF
922 	dsi->bridge.of_node = pdev->dev.of_node;
923 #endif
924 
925 	dev_set_drvdata(dev, dsi);
926 
927 	return dsi;
928 }
929 
930 static void __dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
931 {
932 	pm_runtime_disable(dsi->dev);
933 }
934 
935 /*
936  * Probe/remove API, used from platforms based on the DRM bridge API.
937  */
938 int dw_mipi_dsi_probe(struct platform_device *pdev,
939 		      const struct dw_mipi_dsi_plat_data *plat_data)
940 {
941 	struct dw_mipi_dsi *dsi;
942 
943 	dsi = __dw_mipi_dsi_probe(pdev, plat_data);
944 	if (IS_ERR(dsi))
945 		return PTR_ERR(dsi);
946 
947 	return 0;
948 }
949 EXPORT_SYMBOL_GPL(dw_mipi_dsi_probe);
950 
951 void dw_mipi_dsi_remove(struct platform_device *pdev)
952 {
953 	struct dw_mipi_dsi *dsi = platform_get_drvdata(pdev);
954 
955 	mipi_dsi_host_unregister(&dsi->dsi_host);
956 
957 	__dw_mipi_dsi_remove(dsi);
958 }
959 EXPORT_SYMBOL_GPL(dw_mipi_dsi_remove);
960 
961 /*
962  * Bind/unbind API, used from platforms based on the component framework.
963  */
964 int dw_mipi_dsi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
965 		     const struct dw_mipi_dsi_plat_data *plat_data)
966 {
967 	struct dw_mipi_dsi *dsi;
968 	int ret;
969 
970 	dsi = __dw_mipi_dsi_probe(pdev, plat_data);
971 	if (IS_ERR(dsi))
972 		return PTR_ERR(dsi);
973 
974 	ret = drm_bridge_attach(encoder, &dsi->bridge, NULL);
975 	if (ret) {
976 		dw_mipi_dsi_remove(pdev);
977 		DRM_ERROR("Failed to initialize bridge with drm\n");
978 		return ret;
979 	}
980 
981 	return 0;
982 }
983 EXPORT_SYMBOL_GPL(dw_mipi_dsi_bind);
984 
985 void dw_mipi_dsi_unbind(struct device *dev)
986 {
987 	struct dw_mipi_dsi *dsi = dev_get_drvdata(dev);
988 
989 	__dw_mipi_dsi_remove(dsi);
990 }
991 EXPORT_SYMBOL_GPL(dw_mipi_dsi_unbind);
992 
993 MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
994 MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
995 MODULE_DESCRIPTION("DW MIPI DSI host controller driver");
996 MODULE_LICENSE("GPL");
997 MODULE_ALIAS("platform:dw-mipi-dsi");
998