1// SPDX-License-Identifier: GPL-2.0+
2#include <linux/clk.h>
3#include <linux/component.h>
4#include <linux/delay.h>
5#include <linux/io.h>
6#include <linux/mfd/syscon.h>
7#include <linux/module.h>
8#include <linux/of.h>
9#include <linux/platform_device.h>
10#include <linux/regmap.h>
11#include <linux/regulator/consumer.h>
12#include <video/mipi_display.h>
13
14#include <drm/drm_atomic_helper.h>
15#include <drm/drm_bridge.h>
16#include <drm/drm_device.h>
17#include <drm/drm_drv.h>
18#include <drm/drm_encoder.h>
19#include <drm/drm_mipi_dsi.h>
20#include <drm/drm_modeset_helper_vtables.h>
21#include <drm/drm_of.h>
22#include <drm/drm_panel.h>
23#include <drm/drm_print.h>
24#include <drm/drm_probe_helper.h>
25
26#include "mcde_drm.h"
27#include "mcde_dsi_regs.h"
28
29#define DSI_DEFAULT_LP_FREQ_HZ	19200000
30#define DSI_DEFAULT_HS_FREQ_HZ	420160000
31
32/* PRCMU DSI reset registers */
33#define PRCM_DSI_SW_RESET 0x324
34#define PRCM_DSI_SW_RESET_DSI0_SW_RESETN BIT(0)
35#define PRCM_DSI_SW_RESET_DSI1_SW_RESETN BIT(1)
36#define PRCM_DSI_SW_RESET_DSI2_SW_RESETN BIT(2)
37
38struct mcde_dsi {
39	struct device *dev;
40	struct mcde *mcde;
41	struct drm_bridge bridge;
42	struct drm_panel *panel;
43	struct drm_bridge *bridge_out;
44	struct mipi_dsi_host dsi_host;
45	struct mipi_dsi_device *mdsi;
46	const struct drm_display_mode *mode;
47	struct clk *hs_clk;
48	struct clk *lp_clk;
49	unsigned long hs_freq;
50	unsigned long lp_freq;
51	bool unused;
52
53	void __iomem *regs;
54	struct regmap *prcmu;
55};
56
57static inline struct mcde_dsi *bridge_to_mcde_dsi(struct drm_bridge *bridge)
58{
59	return container_of(bridge, struct mcde_dsi, bridge);
60}
61
62static inline struct mcde_dsi *host_to_mcde_dsi(struct mipi_dsi_host *h)
63{
64	return container_of(h, struct mcde_dsi, dsi_host);
65}
66
67bool mcde_dsi_irq(struct mipi_dsi_device *mdsi)
68{
69	struct mcde_dsi *d;
70	u32 val;
71	bool te_received = false;
72
73	d = host_to_mcde_dsi(mdsi->host);
74
75	dev_dbg(d->dev, "%s called\n", __func__);
76
77	val = readl(d->regs + DSI_DIRECT_CMD_STS_FLAG);
78	if (val)
79		dev_dbg(d->dev, "DSI_DIRECT_CMD_STS_FLAG = %08x\n", val);
80	if (val & DSI_DIRECT_CMD_STS_WRITE_COMPLETED)
81		dev_dbg(d->dev, "direct command write completed\n");
82	if (val & DSI_DIRECT_CMD_STS_TE_RECEIVED) {
83		te_received = true;
84		dev_dbg(d->dev, "direct command TE received\n");
85	}
86	if (val & DSI_DIRECT_CMD_STS_ACKNOWLEDGE_WITH_ERR_RECEIVED)
87		dev_err(d->dev, "direct command ACK ERR received\n");
88	if (val & DSI_DIRECT_CMD_STS_READ_COMPLETED_WITH_ERR)
89		dev_err(d->dev, "direct command read ERR received\n");
90	/* Mask off the ACK value and clear status */
91	writel(val, d->regs + DSI_DIRECT_CMD_STS_CLR);
92
93	val = readl(d->regs + DSI_CMD_MODE_STS_FLAG);
94	if (val)
95		dev_dbg(d->dev, "DSI_CMD_MODE_STS_FLAG = %08x\n", val);
96	if (val & DSI_CMD_MODE_STS_ERR_NO_TE)
97		/* This happens all the time (safe to ignore) */
98		dev_dbg(d->dev, "CMD mode no TE\n");
99	if (val & DSI_CMD_MODE_STS_ERR_TE_MISS)
100		/* This happens all the time (safe to ignore) */
101		dev_dbg(d->dev, "CMD mode TE miss\n");
102	if (val & DSI_CMD_MODE_STS_ERR_SDI1_UNDERRUN)
103		dev_err(d->dev, "CMD mode SD1 underrun\n");
104	if (val & DSI_CMD_MODE_STS_ERR_SDI2_UNDERRUN)
105		dev_err(d->dev, "CMD mode SD2 underrun\n");
106	if (val & DSI_CMD_MODE_STS_ERR_UNWANTED_RD)
107		dev_err(d->dev, "CMD mode unwanted RD\n");
108	writel(val, d->regs + DSI_CMD_MODE_STS_CLR);
109
110	val = readl(d->regs + DSI_DIRECT_CMD_RD_STS_FLAG);
111	if (val)
112		dev_dbg(d->dev, "DSI_DIRECT_CMD_RD_STS_FLAG = %08x\n", val);
113	writel(val, d->regs + DSI_DIRECT_CMD_RD_STS_CLR);
114
115	val = readl(d->regs + DSI_TG_STS_FLAG);
116	if (val)
117		dev_dbg(d->dev, "DSI_TG_STS_FLAG = %08x\n", val);
118	writel(val, d->regs + DSI_TG_STS_CLR);
119
120	val = readl(d->regs + DSI_VID_MODE_STS_FLAG);
121	if (val)
122		dev_dbg(d->dev, "DSI_VID_MODE_STS_FLAG = %08x\n", val);
123	if (val & DSI_VID_MODE_STS_VSG_RUNNING)
124		dev_dbg(d->dev, "VID mode VSG running\n");
125	if (val & DSI_VID_MODE_STS_ERR_MISSING_DATA)
126		dev_err(d->dev, "VID mode missing data\n");
127	if (val & DSI_VID_MODE_STS_ERR_MISSING_HSYNC)
128		dev_err(d->dev, "VID mode missing HSYNC\n");
129	if (val & DSI_VID_MODE_STS_ERR_MISSING_VSYNC)
130		dev_err(d->dev, "VID mode missing VSYNC\n");
131	if (val & DSI_VID_MODE_STS_REG_ERR_SMALL_LENGTH)
132		dev_err(d->dev, "VID mode less bytes than expected between two HSYNC\n");
133	if (val & DSI_VID_MODE_STS_REG_ERR_SMALL_HEIGHT)
134		dev_err(d->dev, "VID mode less lines than expected between two VSYNC\n");
135	if (val & (DSI_VID_MODE_STS_ERR_BURSTWRITE |
136		   DSI_VID_MODE_STS_ERR_LINEWRITE |
137		   DSI_VID_MODE_STS_ERR_LONGREAD))
138		dev_err(d->dev, "VID mode read/write error\n");
139	if (val & DSI_VID_MODE_STS_ERR_VRS_WRONG_LENGTH)
140		dev_err(d->dev, "VID mode received packets differ from expected size\n");
141	if (val & DSI_VID_MODE_STS_VSG_RECOVERY)
142		dev_err(d->dev, "VID mode VSG in recovery mode\n");
143	writel(val, d->regs + DSI_VID_MODE_STS_CLR);
144
145	return te_received;
146}
147
148static void mcde_dsi_attach_to_mcde(struct mcde_dsi *d)
149{
150	d->mcde->mdsi = d->mdsi;
151
152	/*
153	 * Select the way the DSI data flow is pushing to the display:
154	 * currently we just support video or command mode depending
155	 * on the type of display. Video mode defaults to using the
156	 * formatter itself for synchronization (stateless video panel).
157	 *
158	 * FIXME: add flags to struct mipi_dsi_device .flags to indicate
159	 * displays that require BTA (bus turn around) so we can handle
160	 * such displays as well. Figure out how to properly handle
161	 * single frame on-demand updates with DRM for command mode
162	 * displays (MCDE_COMMAND_ONESHOT_FLOW).
163	 */
164	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO)
165		d->mcde->flow_mode = MCDE_VIDEO_FORMATTER_FLOW;
166	else
167		d->mcde->flow_mode = MCDE_COMMAND_TE_FLOW;
168}
169
170static int mcde_dsi_host_attach(struct mipi_dsi_host *host,
171				struct mipi_dsi_device *mdsi)
172{
173	struct mcde_dsi *d = host_to_mcde_dsi(host);
174
175	if (mdsi->lanes < 1 || mdsi->lanes > 2) {
176		DRM_ERROR("dsi device params invalid, 1 or 2 lanes supported\n");
177		return -EINVAL;
178	}
179
180	dev_info(d->dev, "attached DSI device with %d lanes\n", mdsi->lanes);
181	/* MIPI_DSI_FMT_RGB88 etc */
182	dev_info(d->dev, "format %08x, %dbpp\n", mdsi->format,
183		 mipi_dsi_pixel_format_to_bpp(mdsi->format));
184	dev_info(d->dev, "mode flags: %08lx\n", mdsi->mode_flags);
185
186	d->mdsi = mdsi;
187	if (d->mcde)
188		mcde_dsi_attach_to_mcde(d);
189
190	return 0;
191}
192
193static int mcde_dsi_host_detach(struct mipi_dsi_host *host,
194				struct mipi_dsi_device *mdsi)
195{
196	struct mcde_dsi *d = host_to_mcde_dsi(host);
197
198	d->mdsi = NULL;
199	if (d->mcde)
200		d->mcde->mdsi = NULL;
201
202	return 0;
203}
204
205#define MCDE_DSI_HOST_IS_READ(type)			    \
206	((type == MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM) || \
207	 (type == MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM) || \
208	 (type == MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM) || \
209	 (type == MIPI_DSI_DCS_READ))
210
211static int mcde_dsi_execute_transfer(struct mcde_dsi *d,
212				     const struct mipi_dsi_msg *msg)
213{
214	const u32 loop_delay_us = 10; /* us */
215	u32 loop_counter;
216	size_t txlen = msg->tx_len;
217	size_t rxlen = msg->rx_len;
218	int i;
219	u32 val;
220	int ret;
221
222	writel(~0, d->regs + DSI_DIRECT_CMD_STS_CLR);
223	writel(~0, d->regs + DSI_CMD_MODE_STS_CLR);
224	/* Send command */
225	writel(1, d->regs + DSI_DIRECT_CMD_SEND);
226
227	loop_counter = 1000 * 1000 / loop_delay_us;
228	if (MCDE_DSI_HOST_IS_READ(msg->type)) {
229		/* Read command */
230		while (!(readl(d->regs + DSI_DIRECT_CMD_STS) &
231			 (DSI_DIRECT_CMD_STS_READ_COMPLETED |
232			  DSI_DIRECT_CMD_STS_READ_COMPLETED_WITH_ERR))
233		       && --loop_counter)
234			usleep_range(loop_delay_us, (loop_delay_us * 3) / 2);
235		if (!loop_counter) {
236			dev_err(d->dev, "DSI read timeout!\n");
237			/* Set exit code and retry */
238			return -ETIME;
239		}
240	} else {
241		/* Writing only */
242		while (!(readl(d->regs + DSI_DIRECT_CMD_STS) &
243			 DSI_DIRECT_CMD_STS_WRITE_COMPLETED)
244		       && --loop_counter)
245			usleep_range(loop_delay_us, (loop_delay_us * 3) / 2);
246
247		if (!loop_counter) {
248			/* Set exit code and retry */
249			dev_err(d->dev, "DSI write timeout!\n");
250			return -ETIME;
251		}
252	}
253
254	val = readl(d->regs + DSI_DIRECT_CMD_STS);
255	if (val & DSI_DIRECT_CMD_STS_READ_COMPLETED_WITH_ERR) {
256		dev_err(d->dev, "read completed with error\n");
257		writel(1, d->regs + DSI_DIRECT_CMD_RD_INIT);
258		return -EIO;
259	}
260	if (val & DSI_DIRECT_CMD_STS_ACKNOWLEDGE_WITH_ERR_RECEIVED) {
261		val >>= DSI_DIRECT_CMD_STS_ACK_VAL_SHIFT;
262		dev_err(d->dev, "error during transmission: %04x\n",
263			val);
264		return -EIO;
265	}
266
267	if (!MCDE_DSI_HOST_IS_READ(msg->type)) {
268		/* Return number of bytes written */
269		ret = txlen;
270	} else {
271		/* OK this is a read command, get the response */
272		u32 rdsz;
273		u32 rddat;
274		u8 *rx = msg->rx_buf;
275
276		rdsz = readl(d->regs + DSI_DIRECT_CMD_RD_PROPERTY);
277		rdsz &= DSI_DIRECT_CMD_RD_PROPERTY_RD_SIZE_MASK;
278		rddat = readl(d->regs + DSI_DIRECT_CMD_RDDAT);
279		if (rdsz < rxlen) {
280			dev_err(d->dev, "read error, requested %zd got %d\n",
281				rxlen, rdsz);
282			return -EIO;
283		}
284		/* FIXME: read more than 4 bytes */
285		for (i = 0; i < 4 && i < rxlen; i++)
286			rx[i] = (rddat >> (i * 8)) & 0xff;
287		ret = rdsz;
288	}
289
290	/* Successful transmission */
291	return ret;
292}
293
294static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host,
295				      const struct mipi_dsi_msg *msg)
296{
297	struct mcde_dsi *d = host_to_mcde_dsi(host);
298	const u8 *tx = msg->tx_buf;
299	size_t txlen = msg->tx_len;
300	size_t rxlen = msg->rx_len;
301	unsigned int retries = 0;
302	u32 val;
303	int ret;
304	int i;
305
306	if (txlen > 16) {
307		dev_err(d->dev,
308			"dunno how to write more than 16 bytes yet\n");
309		return -EIO;
310	}
311	if (rxlen > 4) {
312		dev_err(d->dev,
313			"dunno how to read more than 4 bytes yet\n");
314		return -EIO;
315	}
316
317	dev_dbg(d->dev,
318		"message to channel %d, write %zd bytes read %zd bytes\n",
319		msg->channel, txlen, rxlen);
320
321	/* Command "nature" */
322	if (MCDE_DSI_HOST_IS_READ(msg->type))
323		/* MCTL_MAIN_DATA_CTL already set up */
324		val = DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_NAT_READ;
325	else
326		val = DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_NAT_WRITE;
327	/*
328	 * More than 2 bytes will not fit in a single packet, so it's
329	 * time to set the "long not short" bit. One byte is used by
330	 * the MIPI DCS command leaving just one byte for the payload
331	 * in a short package.
332	 */
333	if (mipi_dsi_packet_format_is_long(msg->type))
334		val |= DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_LONGNOTSHORT;
335	val |= 0 << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_ID_SHIFT;
336	val |= txlen << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_SIZE_SHIFT;
337	val |= DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_LP_EN;
338	val |= msg->type << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_HEAD_SHIFT;
339	writel(val, d->regs + DSI_DIRECT_CMD_MAIN_SETTINGS);
340
341	/* MIPI DCS command is part of the data */
342	if (txlen > 0) {
343		val = 0;
344		for (i = 0; i < 4 && i < txlen; i++)
345			val |= tx[i] << (i * 8);
346	}
347	writel(val, d->regs + DSI_DIRECT_CMD_WRDAT0);
348	if (txlen > 4) {
349		val = 0;
350		for (i = 0; i < 4 && (i + 4) < txlen; i++)
351			val |= tx[i + 4] << (i * 8);
352		writel(val, d->regs + DSI_DIRECT_CMD_WRDAT1);
353	}
354	if (txlen > 8) {
355		val = 0;
356		for (i = 0; i < 4 && (i + 8) < txlen; i++)
357			val |= tx[i + 8] << (i * 8);
358		writel(val, d->regs + DSI_DIRECT_CMD_WRDAT2);
359	}
360	if (txlen > 12) {
361		val = 0;
362		for (i = 0; i < 4 && (i + 12) < txlen; i++)
363			val |= tx[i + 12] << (i * 8);
364		writel(val, d->regs + DSI_DIRECT_CMD_WRDAT3);
365	}
366
367	while (retries < 3) {
368		ret = mcde_dsi_execute_transfer(d, msg);
369		if (ret >= 0)
370			break;
371		retries++;
372	}
373	if (ret < 0 && retries)
374		dev_err(d->dev, "gave up after %d retries\n", retries);
375
376	/* Clear any errors */
377	writel(~0, d->regs + DSI_DIRECT_CMD_STS_CLR);
378	writel(~0, d->regs + DSI_CMD_MODE_STS_CLR);
379
380	return ret;
381}
382
383static const struct mipi_dsi_host_ops mcde_dsi_host_ops = {
384	.attach = mcde_dsi_host_attach,
385	.detach = mcde_dsi_host_detach,
386	.transfer = mcde_dsi_host_transfer,
387};
388
389/* This sends a direct (short) command to request TE */
390void mcde_dsi_te_request(struct mipi_dsi_device *mdsi)
391{
392	struct mcde_dsi *d;
393	u32 val;
394
395	d = host_to_mcde_dsi(mdsi->host);
396
397	/* Command "nature" TE request */
398	val = DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_NAT_TE_REQ;
399	val |= 0 << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_ID_SHIFT;
400	val |= 2 << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_SIZE_SHIFT;
401	val |= DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_LP_EN;
402	val |= MIPI_DSI_GENERIC_SHORT_WRITE_1_PARAM <<
403		DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_HEAD_SHIFT;
404	writel(val, d->regs + DSI_DIRECT_CMD_MAIN_SETTINGS);
405
406	/* Clear TE reveived and error status bits and enables them */
407	writel(DSI_DIRECT_CMD_STS_CLR_TE_RECEIVED_CLR |
408	       DSI_DIRECT_CMD_STS_CLR_ACKNOWLEDGE_WITH_ERR_RECEIVED_CLR,
409	       d->regs + DSI_DIRECT_CMD_STS_CLR);
410	val = readl(d->regs + DSI_DIRECT_CMD_STS_CTL);
411	val |= DSI_DIRECT_CMD_STS_CTL_TE_RECEIVED_EN;
412	val |= DSI_DIRECT_CMD_STS_CTL_ACKNOWLEDGE_WITH_ERR_EN;
413	writel(val, d->regs + DSI_DIRECT_CMD_STS_CTL);
414
415	/* Clear and enable no TE or TE missing status */
416	writel(DSI_CMD_MODE_STS_CLR_ERR_NO_TE_CLR |
417	       DSI_CMD_MODE_STS_CLR_ERR_TE_MISS_CLR,
418	       d->regs + DSI_CMD_MODE_STS_CLR);
419	val = readl(d->regs + DSI_CMD_MODE_STS_CTL);
420	val |= DSI_CMD_MODE_STS_CTL_ERR_NO_TE_EN;
421	val |= DSI_CMD_MODE_STS_CTL_ERR_TE_MISS_EN;
422	writel(val, d->regs + DSI_CMD_MODE_STS_CTL);
423
424	/* Send this TE request command */
425	writel(1, d->regs + DSI_DIRECT_CMD_SEND);
426}
427
428static void mcde_dsi_setup_video_mode(struct mcde_dsi *d,
429				      const struct drm_display_mode *mode)
430{
431	/* cpp, characters per pixel, number of bytes per pixel */
432	u8 cpp = mipi_dsi_pixel_format_to_bpp(d->mdsi->format) / 8;
433	u64 pclk;
434	u64 bpl;
435	int hfp;
436	int hbp;
437	int hsa;
438	u32 blkline_pck, line_duration;
439	u32 val;
440
441	val = 0;
442	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
443		val |= DSI_VID_MAIN_CTL_BURST_MODE;
444	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
445		val |= DSI_VID_MAIN_CTL_SYNC_PULSE_ACTIVE;
446		val |= DSI_VID_MAIN_CTL_SYNC_PULSE_HORIZONTAL;
447	}
448	/* RGB header and pixel mode */
449	switch (d->mdsi->format) {
450	case MIPI_DSI_FMT_RGB565:
451		val |= MIPI_DSI_PACKED_PIXEL_STREAM_16 <<
452			DSI_VID_MAIN_CTL_HEADER_SHIFT;
453		val |= DSI_VID_MAIN_CTL_VID_PIXEL_MODE_16BITS;
454		break;
455	case MIPI_DSI_FMT_RGB666_PACKED:
456		val |= MIPI_DSI_PACKED_PIXEL_STREAM_18 <<
457			DSI_VID_MAIN_CTL_HEADER_SHIFT;
458		val |= DSI_VID_MAIN_CTL_VID_PIXEL_MODE_18BITS;
459		break;
460	case MIPI_DSI_FMT_RGB666:
461		val |= MIPI_DSI_PIXEL_STREAM_3BYTE_18
462			<< DSI_VID_MAIN_CTL_HEADER_SHIFT;
463		val |= DSI_VID_MAIN_CTL_VID_PIXEL_MODE_18BITS_LOOSE;
464		break;
465	case MIPI_DSI_FMT_RGB888:
466		val |= MIPI_DSI_PACKED_PIXEL_STREAM_24 <<
467			DSI_VID_MAIN_CTL_HEADER_SHIFT;
468		val |= DSI_VID_MAIN_CTL_VID_PIXEL_MODE_24BITS;
469		break;
470	default:
471		dev_err(d->dev, "unknown pixel mode\n");
472		return;
473	}
474
475	/* TODO: TVG (test video generator) could be enabled here */
476
477	/*
478	 * During vertical blanking: go to LP mode
479	 * Like with the EOL setting, if this is not set, the EOL area will be
480	 * filled with NULL or blanking packets in the vblank area.
481	 * FIXME: some Samsung phones and display panels such as s6e63m0 use
482	 * DSI_VID_MAIN_CTL_REG_BLKLINE_MODE_BLANKING here instead,
483	 * figure out how to properly configure that from the panel.
484	 */
485	val |= DSI_VID_MAIN_CTL_REG_BLKLINE_MODE_LP_0;
486	/*
487	 * During EOL: go to LP mode. If this is not set, the EOL area will be
488	 * filled with NULL or blanking packets.
489	 */
490	val |= DSI_VID_MAIN_CTL_REG_BLKEOL_MODE_LP_0;
491	/* Recovery mode 1 */
492	val |= 1 << DSI_VID_MAIN_CTL_RECOVERY_MODE_SHIFT;
493	/* All other fields zero */
494	writel(val, d->regs + DSI_VID_MAIN_CTL);
495
496	/* Vertical frame parameters are pretty straight-forward */
497	val = mode->vdisplay << DSI_VID_VSIZE_VACT_LENGTH_SHIFT;
498	/* vertical front porch */
499	val |= (mode->vsync_start - mode->vdisplay)
500		<< DSI_VID_VSIZE_VFP_LENGTH_SHIFT;
501	/* vertical sync active */
502	val |= (mode->vsync_end - mode->vsync_start)
503		<< DSI_VID_VSIZE_VSA_LENGTH_SHIFT;
504	/* vertical back porch */
505	val |= (mode->vtotal - mode->vsync_end)
506		<< DSI_VID_VSIZE_VBP_LENGTH_SHIFT;
507	writel(val, d->regs + DSI_VID_VSIZE);
508
509	/*
510	 * Horizontal frame parameters:
511	 * horizontal resolution is given in pixels but must be re-calculated
512	 * into bytes since this is what the hardware expects, these registers
513	 * define the payload size of the packet.
514	 *
515	 * hfp = horizontal front porch in bytes
516	 * hbp = horizontal back porch in bytes
517	 * hsa = horizontal sync active in bytes
518	 *
519	 * 6 + 2 is HFP header + checksum
520	 */
521	hfp = (mode->hsync_start - mode->hdisplay) * cpp - 6 - 2;
522	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
523		/*
524		 * Use sync pulse for sync: explicit HSA time
525		 * 6 is HBP header + checksum
526		 * 4 is RGB header + checksum
527		 */
528		hbp = (mode->htotal - mode->hsync_end) * cpp - 4 - 6;
529		/*
530		 * 6 is HBP header + checksum
531		 * 4 is HSW packet bytes
532		 * 4 is RGB header + checksum
533		 */
534		hsa = (mode->hsync_end - mode->hsync_start) * cpp - 4 - 4 - 6;
535	} else {
536		/*
537		 * Use event for sync: HBP includes both back porch and sync
538		 * 6 is HBP header + checksum
539		 * 4 is HSW packet bytes
540		 * 4 is RGB header + checksum
541		 */
542		hbp = (mode->htotal - mode->hsync_start) * cpp - 4 - 4 - 6;
543		/* HSA is not present in this mode and set to 0 */
544		hsa = 0;
545	}
546	if (hfp < 0) {
547		dev_info(d->dev, "hfp negative, set to 0\n");
548		hfp = 0;
549	}
550	if (hbp < 0) {
551		dev_info(d->dev, "hbp negative, set to 0\n");
552		hbp = 0;
553	}
554	if (hsa < 0) {
555		dev_info(d->dev, "hsa negative, set to 0\n");
556		hsa = 0;
557	}
558	dev_dbg(d->dev, "hfp: %u, hbp: %u, hsa: %u bytes\n",
559		hfp, hbp, hsa);
560
561	/* Frame parameters: horizontal sync active */
562	val = hsa << DSI_VID_HSIZE1_HSA_LENGTH_SHIFT;
563	/* horizontal back porch */
564	val |= hbp << DSI_VID_HSIZE1_HBP_LENGTH_SHIFT;
565	/* horizontal front porch */
566	val |= hfp << DSI_VID_HSIZE1_HFP_LENGTH_SHIFT;
567	writel(val, d->regs + DSI_VID_HSIZE1);
568
569	/* RGB data length (visible bytes on one scanline) */
570	val = mode->hdisplay * cpp;
571	writel(val, d->regs + DSI_VID_HSIZE2);
572	dev_dbg(d->dev, "RGB length, visible area on a line: %u bytes\n", val);
573
574	/*
575	 * Calculate the time between two pixels in picoseconds using
576	 * the supplied refresh rate and total resolution including
577	 * porches and sync.
578	 */
579	/* (ps/s) / (pixels/s) = ps/pixels */
580	pclk = DIV_ROUND_UP_ULL(1000000000000, (mode->clock * 1000));
581	dev_dbg(d->dev, "picoseconds between two pixels: %llu\n",
582		pclk);
583
584	/*
585	 * How many bytes per line will this update frequency yield?
586	 *
587	 * Calculate the number of picoseconds for one scanline (1), then
588	 * divide by 1000000000000 (2) to get in pixels per second we
589	 * want to output.
590	 *
591	 * Multiply with number of bytes per second at this video display
592	 * frequency (3) to get number of bytes transferred during this
593	 * time. Notice that we use the frequency the display wants,
594	 * not what we actually get from the DSI PLL, which is hs_freq.
595	 *
596	 * These arithmetics are done in a different order to avoid
597	 * overflow.
598	 */
599	bpl = pclk * mode->htotal; /* (1) picoseconds per line */
600	dev_dbg(d->dev, "picoseconds per line: %llu\n", bpl);
601	/* Multiply with bytes per second (3) */
602	bpl *= (d->mdsi->hs_rate / 8);
603	/* Pixels per second (2) */
604	bpl = DIV_ROUND_DOWN_ULL(bpl, 1000000); /* microseconds */
605	bpl = DIV_ROUND_DOWN_ULL(bpl, 1000000); /* seconds */
606	/* parallel transactions in all lanes */
607	bpl *= d->mdsi->lanes;
608	dev_dbg(d->dev,
609		"calculated bytes per line: %llu @ %d Hz with HS %lu Hz\n",
610		bpl, drm_mode_vrefresh(mode), d->mdsi->hs_rate);
611
612	/*
613	 * 6 is header + checksum, header = 4 bytes, checksum = 2 bytes
614	 * 4 is short packet for vsync/hsync
615	 */
616	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
617		/* Set the event packet size to 0 (not used) */
618		writel(0, d->regs + DSI_VID_BLKSIZE1);
619		/*
620		 * FIXME: isn't the hsync width in pixels? The porch and
621		 * sync area size is in pixels here, but this -6
622		 * seems to be for bytes. It looks like this in the vendor
623		 * code though. Is it completely untested?
624		 */
625		blkline_pck = bpl - (mode->hsync_end - mode->hsync_start) - 6;
626		val = blkline_pck << DSI_VID_BLKSIZE2_BLKLINE_PULSE_PCK_SHIFT;
627		writel(val, d->regs + DSI_VID_BLKSIZE2);
628	} else {
629		/* Set the sync pulse packet size to 0 (not used) */
630		writel(0, d->regs + DSI_VID_BLKSIZE2);
631		/* Specifying payload size in bytes (-4-6 from manual) */
632		blkline_pck = bpl - 4 - 6;
633		if (blkline_pck > 0x1FFF)
634			dev_err(d->dev, "blkline_pck too big %d bytes\n",
635				blkline_pck);
636		val = blkline_pck << DSI_VID_BLKSIZE1_BLKLINE_EVENT_PCK_SHIFT;
637		val &= DSI_VID_BLKSIZE1_BLKLINE_EVENT_PCK_MASK;
638		writel(val, d->regs + DSI_VID_BLKSIZE1);
639	}
640
641	/*
642	 * The line duration is used to scale back the frequency from
643	 * the max frequency supported by the HS clock to the desired
644	 * update frequency in vrefresh.
645	 */
646	line_duration = blkline_pck + 6;
647	/*
648	 * The datasheet contains this complex condition to decreasing
649	 * the line duration by 1 under very specific circumstances.
650	 * Here we also imply that LP is used during burst EOL.
651	 */
652	if (d->mdsi->lanes == 2 && (hsa & 0x01) && (hfp & 0x01)
653	    && (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST))
654		line_duration--;
655	line_duration = DIV_ROUND_CLOSEST(line_duration, d->mdsi->lanes);
656	dev_dbg(d->dev, "line duration %u bytes\n", line_duration);
657	val = line_duration << DSI_VID_DPHY_TIME_REG_LINE_DURATION_SHIFT;
658	/*
659	 * This is the time to perform LP->HS on D-PHY
660	 * FIXME: nowhere to get this from: DT property on the DSI?
661	 * The manual says this is "system dependent".
662	 * values like 48 and 72 seen in the vendor code.
663	 */
664	val |= 48 << DSI_VID_DPHY_TIME_REG_WAKEUP_TIME_SHIFT;
665	writel(val, d->regs + DSI_VID_DPHY_TIME);
666
667	/*
668	 * See the manual figure 657 page 2203 for understanding the impact
669	 * of the different burst mode settings.
670	 */
671	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) {
672		int blkeol_pck, blkeol_duration;
673		/*
674		 * Packet size at EOL for burst mode, this is only used
675		 * if DSI_VID_MAIN_CTL_REG_BLKEOL_MODE_LP_0 is NOT set,
676		 * but we instead send NULL or blanking packets at EOL.
677		 * This is given in number of bytes.
678		 *
679		 * See the manual page 2198 for the 13 reg_blkeol_pck bits.
680		 */
681		blkeol_pck = bpl - (mode->htotal * cpp) - 6;
682		if (blkeol_pck < 0) {
683			dev_err(d->dev, "video block does not fit on line!\n");
684			dev_err(d->dev,
685				"calculated bytes per line: %llu @ %d Hz\n",
686				bpl, drm_mode_vrefresh(mode));
687			dev_err(d->dev,
688				"bytes per line (blkline_pck) %u bytes\n",
689				blkline_pck);
690			dev_err(d->dev,
691				"blkeol_pck becomes %d bytes\n", blkeol_pck);
692			return;
693		}
694		dev_dbg(d->dev, "BLKEOL packet: %d bytes\n", blkeol_pck);
695
696		val = readl(d->regs + DSI_VID_BLKSIZE1);
697		val &= ~DSI_VID_BLKSIZE1_BLKEOL_PCK_MASK;
698		val |= blkeol_pck << DSI_VID_BLKSIZE1_BLKEOL_PCK_SHIFT;
699		writel(val, d->regs + DSI_VID_BLKSIZE1);
700		/* Use the same value for exact burst limit */
701		val = blkeol_pck <<
702			DSI_VID_VCA_SETTING2_EXACT_BURST_LIMIT_SHIFT;
703		val &= DSI_VID_VCA_SETTING2_EXACT_BURST_LIMIT_MASK;
704		writel(val, d->regs + DSI_VID_VCA_SETTING2);
705		/*
706		 * This BLKEOL duration is claimed to be the duration in clock
707		 * cycles of the BLLP end-of-line (EOL) period for each line if
708		 * DSI_VID_MAIN_CTL_REG_BLKEOL_MODE_LP_0 is set.
709		 *
710		 * It is hard to trust the manuals' claim that this is in clock
711		 * cycles as we mimic the behaviour of the vendor code, which
712		 * appears to write a number of bytes that would have been
713		 * transferred on a single lane.
714		 *
715		 * See the manual figure 657 page 2203 and page 2198 for the 13
716		 * reg_blkeol_duration bits.
717		 *
718		 * FIXME: should this also be set up also for non-burst mode
719		 * according to figure 565 page 2202?
720		 */
721		blkeol_duration = DIV_ROUND_CLOSEST(blkeol_pck + 6,
722						    d->mdsi->lanes);
723		dev_dbg(d->dev, "BLKEOL duration: %d clock cycles\n",
724			blkeol_duration);
725
726		val = readl(d->regs + DSI_VID_PCK_TIME);
727		val &= ~DSI_VID_PCK_TIME_BLKEOL_DURATION_MASK;
728		val |= blkeol_duration <<
729			DSI_VID_PCK_TIME_BLKEOL_DURATION_SHIFT;
730		writel(val, d->regs + DSI_VID_PCK_TIME);
731
732		/* Max burst limit, this is given in bytes */
733		val = readl(d->regs + DSI_VID_VCA_SETTING1);
734		val &= ~DSI_VID_VCA_SETTING1_MAX_BURST_LIMIT_MASK;
735		val |= (blkeol_pck - 6) <<
736			DSI_VID_VCA_SETTING1_MAX_BURST_LIMIT_SHIFT;
737		writel(val, d->regs + DSI_VID_VCA_SETTING1);
738	}
739
740	/* Maximum line limit */
741	val = readl(d->regs + DSI_VID_VCA_SETTING2);
742	val &= ~DSI_VID_VCA_SETTING2_MAX_LINE_LIMIT_MASK;
743	val |= (blkline_pck - 6) <<
744		DSI_VID_VCA_SETTING2_MAX_LINE_LIMIT_SHIFT;
745	writel(val, d->regs + DSI_VID_VCA_SETTING2);
746	dev_dbg(d->dev, "blkline pck: %d bytes\n", blkline_pck - 6);
747}
748
749static void mcde_dsi_start(struct mcde_dsi *d)
750{
751	unsigned long hs_freq;
752	u32 val;
753	int i;
754
755	/* No integration mode */
756	writel(0, d->regs + DSI_MCTL_INTEGRATION_MODE);
757
758	/* Enable the DSI port, from drivers/video/mcde/dsilink_v2.c */
759	val = DSI_MCTL_MAIN_DATA_CTL_LINK_EN |
760		DSI_MCTL_MAIN_DATA_CTL_BTA_EN |
761		DSI_MCTL_MAIN_DATA_CTL_READ_EN |
762		DSI_MCTL_MAIN_DATA_CTL_REG_TE_EN;
763	if (!(d->mdsi->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET))
764		val |= DSI_MCTL_MAIN_DATA_CTL_HOST_EOT_GEN;
765	writel(val, d->regs + DSI_MCTL_MAIN_DATA_CTL);
766
767	/* Set a high command timeout, clear other fields */
768	val = 0x3ff << DSI_CMD_MODE_CTL_TE_TIMEOUT_SHIFT;
769	writel(val, d->regs + DSI_CMD_MODE_CTL);
770
771	/*
772	 * UI_X4 is described as "unit interval times four"
773	 * I guess since DSI packets are 4 bytes wide, one unit
774	 * is one byte.
775	 */
776	hs_freq = clk_get_rate(d->hs_clk);
777	hs_freq /= 1000000; /* MHz */
778	val = 4000 / hs_freq;
779	dev_dbg(d->dev, "UI value: %d\n", val);
780	val <<= DSI_MCTL_DPHY_STATIC_UI_X4_SHIFT;
781	val &= DSI_MCTL_DPHY_STATIC_UI_X4_MASK;
782	writel(val, d->regs + DSI_MCTL_DPHY_STATIC);
783
784	/*
785	 * Enable clocking: 0x0f (something?) between each burst,
786	 * enable the second lane if needed, enable continuous clock if
787	 * needed, enable switch into ULPM (ultra-low power mode) on
788	 * all the lines.
789	 */
790	val = 0x0f << DSI_MCTL_MAIN_PHY_CTL_WAIT_BURST_TIME_SHIFT;
791	if (d->mdsi->lanes == 2)
792		val |= DSI_MCTL_MAIN_PHY_CTL_LANE2_EN;
793	if (!(d->mdsi->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS))
794		val |= DSI_MCTL_MAIN_PHY_CTL_CLK_CONTINUOUS;
795	val |= DSI_MCTL_MAIN_PHY_CTL_CLK_ULPM_EN |
796		DSI_MCTL_MAIN_PHY_CTL_DAT1_ULPM_EN |
797		DSI_MCTL_MAIN_PHY_CTL_DAT2_ULPM_EN;
798	writel(val, d->regs + DSI_MCTL_MAIN_PHY_CTL);
799
800	val = (1 << DSI_MCTL_ULPOUT_TIME_CKLANE_ULPOUT_TIME_SHIFT) |
801		(1 << DSI_MCTL_ULPOUT_TIME_DATA_ULPOUT_TIME_SHIFT);
802	writel(val, d->regs + DSI_MCTL_ULPOUT_TIME);
803
804	writel(DSI_DPHY_LANES_TRIM_DPHY_SPECS_90_81B_0_90,
805	       d->regs + DSI_DPHY_LANES_TRIM);
806
807	/* High PHY timeout */
808	val = (0x0f << DSI_MCTL_DPHY_TIMEOUT_CLK_DIV_SHIFT) |
809		(0x3fff << DSI_MCTL_DPHY_TIMEOUT_HSTX_TO_VAL_SHIFT) |
810		(0x3fff << DSI_MCTL_DPHY_TIMEOUT_LPRX_TO_VAL_SHIFT);
811	writel(val, d->regs + DSI_MCTL_DPHY_TIMEOUT);
812
813	val = DSI_MCTL_MAIN_EN_PLL_START |
814		DSI_MCTL_MAIN_EN_CKLANE_EN |
815		DSI_MCTL_MAIN_EN_DAT1_EN |
816		DSI_MCTL_MAIN_EN_IF1_EN;
817	if (d->mdsi->lanes == 2)
818		val |= DSI_MCTL_MAIN_EN_DAT2_EN;
819	writel(val, d->regs + DSI_MCTL_MAIN_EN);
820
821	/* Wait for the PLL to lock and the clock and data lines to come up */
822	i = 0;
823	val = DSI_MCTL_MAIN_STS_PLL_LOCK |
824		DSI_MCTL_MAIN_STS_CLKLANE_READY |
825		DSI_MCTL_MAIN_STS_DAT1_READY;
826	if (d->mdsi->lanes == 2)
827		val |= DSI_MCTL_MAIN_STS_DAT2_READY;
828	while ((readl(d->regs + DSI_MCTL_MAIN_STS) & val) != val) {
829		/* Sleep for a millisecond */
830		usleep_range(1000, 1500);
831		if (i++ == 100) {
832			dev_warn(d->dev, "DSI lanes did not start up\n");
833			return;
834		}
835	}
836
837	/* TODO needed? */
838
839	/* Command mode, clear IF1 ID */
840	val = readl(d->regs + DSI_CMD_MODE_CTL);
841	/*
842	 * If we enable low-power mode here,
843	 * then display updates become really slow.
844	 */
845	if (d->mdsi->mode_flags & MIPI_DSI_MODE_LPM)
846		val |= DSI_CMD_MODE_CTL_IF1_LP_EN;
847	val &= ~DSI_CMD_MODE_CTL_IF1_ID_MASK;
848	writel(val, d->regs + DSI_CMD_MODE_CTL);
849
850	/* Wait for DSI PHY to initialize */
851	usleep_range(100, 200);
852	dev_info(d->dev, "DSI link enabled\n");
853}
854
855/*
856 * Notice that this is called from inside the display controller
857 * and not from the bridge callbacks.
858 */
859void mcde_dsi_enable(struct drm_bridge *bridge)
860{
861	struct mcde_dsi *d = bridge_to_mcde_dsi(bridge);
862	unsigned long hs_freq, lp_freq;
863	u32 val;
864	int ret;
865
866	/* Copy maximum clock frequencies */
867	if (d->mdsi->lp_rate)
868		lp_freq = d->mdsi->lp_rate;
869	else
870		lp_freq = DSI_DEFAULT_LP_FREQ_HZ;
871	if (d->mdsi->hs_rate)
872		hs_freq = d->mdsi->hs_rate;
873	else
874		hs_freq = DSI_DEFAULT_HS_FREQ_HZ;
875
876	/* Enable LP (Low Power, Energy Save, ES) and HS (High Speed) clocks */
877	d->lp_freq = clk_round_rate(d->lp_clk, lp_freq);
878	ret = clk_set_rate(d->lp_clk, d->lp_freq);
879	if (ret)
880		dev_err(d->dev, "failed to set LP clock rate %lu Hz\n",
881			d->lp_freq);
882
883	d->hs_freq = clk_round_rate(d->hs_clk, hs_freq);
884	ret = clk_set_rate(d->hs_clk, d->hs_freq);
885	if (ret)
886		dev_err(d->dev, "failed to set HS clock rate %lu Hz\n",
887			d->hs_freq);
888
889	/* Start clocks */
890	ret = clk_prepare_enable(d->lp_clk);
891	if (ret)
892		dev_err(d->dev, "failed to enable LP clock\n");
893	else
894		dev_info(d->dev, "DSI LP clock rate %lu Hz\n",
895			 d->lp_freq);
896	ret = clk_prepare_enable(d->hs_clk);
897	if (ret)
898		dev_err(d->dev, "failed to enable HS clock\n");
899	else
900		dev_info(d->dev, "DSI HS clock rate %lu Hz\n",
901			 d->hs_freq);
902
903	/* Assert RESET through the PRCMU, active low */
904	/* FIXME: which DSI block? */
905	regmap_update_bits(d->prcmu, PRCM_DSI_SW_RESET,
906			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN, 0);
907
908	usleep_range(100, 200);
909
910	/* De-assert RESET again */
911	regmap_update_bits(d->prcmu, PRCM_DSI_SW_RESET,
912			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN,
913			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN);
914
915	/* Start up the hardware */
916	mcde_dsi_start(d);
917
918	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
919		/* Set up the video mode from the DRM mode */
920		mcde_dsi_setup_video_mode(d, d->mode);
921
922		/* Put IF1 into video mode */
923		val = readl(d->regs + DSI_MCTL_MAIN_DATA_CTL);
924		val |= DSI_MCTL_MAIN_DATA_CTL_IF1_MODE;
925		writel(val, d->regs + DSI_MCTL_MAIN_DATA_CTL);
926
927		/* Disable command mode on IF1 */
928		val = readl(d->regs + DSI_CMD_MODE_CTL);
929		val &= ~DSI_CMD_MODE_CTL_IF1_LP_EN;
930		writel(val, d->regs + DSI_CMD_MODE_CTL);
931
932		/* Enable some error interrupts */
933		val = readl(d->regs + DSI_VID_MODE_STS_CTL);
934		val |= DSI_VID_MODE_STS_CTL_ERR_MISSING_VSYNC;
935		val |= DSI_VID_MODE_STS_CTL_ERR_MISSING_DATA;
936		writel(val, d->regs + DSI_VID_MODE_STS_CTL);
937
938		/* Enable video mode */
939		val = readl(d->regs + DSI_MCTL_MAIN_DATA_CTL);
940		val |= DSI_MCTL_MAIN_DATA_CTL_VID_EN;
941		writel(val, d->regs + DSI_MCTL_MAIN_DATA_CTL);
942	} else {
943		/* Command mode, clear IF1 ID */
944		val = readl(d->regs + DSI_CMD_MODE_CTL);
945		/*
946		 * If we enable low-power mode here
947		 * the display updates become really slow.
948		 */
949		if (d->mdsi->mode_flags & MIPI_DSI_MODE_LPM)
950			val |= DSI_CMD_MODE_CTL_IF1_LP_EN;
951		val &= ~DSI_CMD_MODE_CTL_IF1_ID_MASK;
952		writel(val, d->regs + DSI_CMD_MODE_CTL);
953	}
954
955	dev_info(d->dev, "enabled MCDE DSI master\n");
956}
957
958static void mcde_dsi_bridge_mode_set(struct drm_bridge *bridge,
959				     const struct drm_display_mode *mode,
960				     const struct drm_display_mode *adj)
961{
962	struct mcde_dsi *d = bridge_to_mcde_dsi(bridge);
963
964	if (!d->mdsi) {
965		dev_err(d->dev, "no DSI device attached to encoder!\n");
966		return;
967	}
968
969	d->mode = mode;
970
971	dev_info(d->dev, "set DSI master to %dx%d %u Hz %s mode\n",
972		 mode->hdisplay, mode->vdisplay, mode->clock * 1000,
973		 (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO) ? "VIDEO" : "CMD"
974		);
975}
976
977static void mcde_dsi_wait_for_command_mode_stop(struct mcde_dsi *d)
978{
979	u32 val;
980	int i;
981
982	/*
983	 * Wait until we get out of command mode
984	 * CSM = Command State Machine
985	 */
986	i = 0;
987	val = DSI_CMD_MODE_STS_CSM_RUNNING;
988	while ((readl(d->regs + DSI_CMD_MODE_STS) & val) == val) {
989		/* Sleep for a millisecond */
990		usleep_range(1000, 2000);
991		if (i++ == 100) {
992			dev_warn(d->dev,
993				 "could not get out of command mode\n");
994			return;
995		}
996	}
997}
998
999static void mcde_dsi_wait_for_video_mode_stop(struct mcde_dsi *d)
1000{
1001	u32 val;
1002	int i;
1003
1004	/* Wait until we get out og video mode */
1005	i = 0;
1006	val = DSI_VID_MODE_STS_VSG_RUNNING;
1007	while ((readl(d->regs + DSI_VID_MODE_STS) & val) == val) {
1008		/* Sleep for a millisecond */
1009		usleep_range(1000, 2000);
1010		if (i++ == 100) {
1011			dev_warn(d->dev,
1012				 "could not get out of video mode\n");
1013			return;
1014		}
1015	}
1016}
1017
1018/*
1019 * Notice that this is called from inside the display controller
1020 * and not from the bridge callbacks.
1021 */
1022void mcde_dsi_disable(struct drm_bridge *bridge)
1023{
1024	struct mcde_dsi *d = bridge_to_mcde_dsi(bridge);
1025	u32 val;
1026
1027	if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
1028		/* Stop video mode */
1029		val = readl(d->regs + DSI_MCTL_MAIN_DATA_CTL);
1030		val &= ~DSI_MCTL_MAIN_DATA_CTL_VID_EN;
1031		writel(val, d->regs + DSI_MCTL_MAIN_DATA_CTL);
1032		mcde_dsi_wait_for_video_mode_stop(d);
1033	} else {
1034		/* Stop command mode */
1035		mcde_dsi_wait_for_command_mode_stop(d);
1036	}
1037
1038	/*
1039	 * Stop clocks and terminate any DSI traffic here so the panel can
1040	 * send commands to shut down the display using DSI direct write until
1041	 * this point.
1042	 */
1043
1044	/* Disable all error interrupts */
1045	writel(0, d->regs + DSI_VID_MODE_STS_CTL);
1046	clk_disable_unprepare(d->hs_clk);
1047	clk_disable_unprepare(d->lp_clk);
1048}
1049
1050static int mcde_dsi_bridge_attach(struct drm_bridge *bridge,
1051				  enum drm_bridge_attach_flags flags)
1052{
1053	struct mcde_dsi *d = bridge_to_mcde_dsi(bridge);
1054	struct drm_device *drm = bridge->dev;
1055
1056	if (!drm_core_check_feature(drm, DRIVER_ATOMIC)) {
1057		dev_err(d->dev, "we need atomic updates\n");
1058		return -ENOTSUPP;
1059	}
1060
1061	/* Attach the DSI bridge to the output (panel etc) bridge */
1062	return drm_bridge_attach(bridge->encoder, d->bridge_out, bridge, flags);
1063}
1064
1065static const struct drm_bridge_funcs mcde_dsi_bridge_funcs = {
1066	.attach = mcde_dsi_bridge_attach,
1067	.mode_set = mcde_dsi_bridge_mode_set,
1068};
1069
1070static int mcde_dsi_bind(struct device *dev, struct device *master,
1071			 void *data)
1072{
1073	struct drm_device *drm = data;
1074	struct mcde *mcde = to_mcde(drm);
1075	struct mcde_dsi *d = dev_get_drvdata(dev);
1076	struct device_node *child;
1077	struct drm_panel *panel = NULL;
1078	struct drm_bridge *bridge = NULL;
1079
1080	if (!of_get_available_child_count(dev->of_node)) {
1081		dev_info(dev, "unused DSI interface\n");
1082		d->unused = true;
1083		return 0;
1084	}
1085	d->mcde = mcde;
1086	/* If the display attached before binding, set this up */
1087	if (d->mdsi)
1088		mcde_dsi_attach_to_mcde(d);
1089
1090	/* Obtain the clocks */
1091	d->hs_clk = devm_clk_get(dev, "hs");
1092	if (IS_ERR(d->hs_clk)) {
1093		dev_err(dev, "unable to get HS clock\n");
1094		return PTR_ERR(d->hs_clk);
1095	}
1096
1097	d->lp_clk = devm_clk_get(dev, "lp");
1098	if (IS_ERR(d->lp_clk)) {
1099		dev_err(dev, "unable to get LP clock\n");
1100		return PTR_ERR(d->lp_clk);
1101	}
1102
1103	/* Look for a panel as a child to this node */
1104	for_each_available_child_of_node(dev->of_node, child) {
1105		panel = of_drm_find_panel(child);
1106		if (IS_ERR(panel)) {
1107			dev_err(dev, "failed to find panel try bridge (%ld)\n",
1108				PTR_ERR(panel));
1109			panel = NULL;
1110
1111			bridge = of_drm_find_bridge(child);
1112			if (!bridge) {
1113				dev_err(dev, "failed to find bridge\n");
1114				of_node_put(child);
1115				return -EINVAL;
1116			}
1117		}
1118	}
1119	if (panel) {
1120		bridge = drm_panel_bridge_add_typed(panel,
1121						    DRM_MODE_CONNECTOR_DSI);
1122		if (IS_ERR(bridge)) {
1123			dev_err(dev, "error adding panel bridge\n");
1124			return PTR_ERR(bridge);
1125		}
1126		dev_info(dev, "connected to panel\n");
1127		d->panel = panel;
1128	} else if (bridge) {
1129		/* TODO: AV8100 HDMI encoder goes here for example */
1130		dev_info(dev, "connected to non-panel bridge (unsupported)\n");
1131		return -ENODEV;
1132	} else {
1133		dev_err(dev, "no panel or bridge\n");
1134		return -ENODEV;
1135	}
1136
1137	d->bridge_out = bridge;
1138
1139	/* Create a bridge for this DSI channel */
1140	d->bridge.funcs = &mcde_dsi_bridge_funcs;
1141	d->bridge.of_node = dev->of_node;
1142	drm_bridge_add(&d->bridge);
1143
1144	/* TODO: first come first serve, use a list */
1145	mcde->bridge = &d->bridge;
1146
1147	dev_info(dev, "initialized MCDE DSI bridge\n");
1148
1149	return 0;
1150}
1151
1152static void mcde_dsi_unbind(struct device *dev, struct device *master,
1153			    void *data)
1154{
1155	struct mcde_dsi *d = dev_get_drvdata(dev);
1156
1157	if (d->panel)
1158		drm_panel_bridge_remove(d->bridge_out);
1159	regmap_update_bits(d->prcmu, PRCM_DSI_SW_RESET,
1160			   PRCM_DSI_SW_RESET_DSI0_SW_RESETN, 0);
1161}
1162
1163static const struct component_ops mcde_dsi_component_ops = {
1164	.bind   = mcde_dsi_bind,
1165	.unbind = mcde_dsi_unbind,
1166};
1167
1168static int mcde_dsi_probe(struct platform_device *pdev)
1169{
1170	struct device *dev = &pdev->dev;
1171	struct mcde_dsi *d;
1172	struct mipi_dsi_host *host;
1173	u32 dsi_id;
1174	int ret;
1175
1176	d = devm_kzalloc(dev, sizeof(*d), GFP_KERNEL);
1177	if (!d)
1178		return -ENOMEM;
1179	d->dev = dev;
1180	platform_set_drvdata(pdev, d);
1181
1182	/* Get a handle on the PRCMU so we can do reset */
1183	d->prcmu =
1184		syscon_regmap_lookup_by_compatible("stericsson,db8500-prcmu");
1185	if (IS_ERR(d->prcmu)) {
1186		dev_err(dev, "no PRCMU regmap\n");
1187		return PTR_ERR(d->prcmu);
1188	}
1189
1190	d->regs = devm_platform_ioremap_resource(pdev, 0);
1191	if (IS_ERR(d->regs))
1192		return PTR_ERR(d->regs);
1193
1194	dsi_id = readl(d->regs + DSI_ID_REG);
1195	dev_info(dev, "HW revision 0x%08x\n", dsi_id);
1196
1197	host = &d->dsi_host;
1198	host->dev = dev;
1199	host->ops = &mcde_dsi_host_ops;
1200	ret = mipi_dsi_host_register(host);
1201	if (ret < 0) {
1202		dev_err(dev, "failed to register DSI host: %d\n", ret);
1203		return ret;
1204	}
1205	dev_info(dev, "registered DSI host\n");
1206
1207	platform_set_drvdata(pdev, d);
1208	return component_add(dev, &mcde_dsi_component_ops);
1209}
1210
1211static void mcde_dsi_remove(struct platform_device *pdev)
1212{
1213	struct mcde_dsi *d = platform_get_drvdata(pdev);
1214
1215	component_del(&pdev->dev, &mcde_dsi_component_ops);
1216	mipi_dsi_host_unregister(&d->dsi_host);
1217}
1218
1219static const struct of_device_id mcde_dsi_of_match[] = {
1220	{
1221		.compatible = "ste,mcde-dsi",
1222	},
1223	{},
1224};
1225
1226struct platform_driver mcde_dsi_driver = {
1227	.driver = {
1228		.name           = "mcde-dsi",
1229		.of_match_table = mcde_dsi_of_match,
1230	},
1231	.probe = mcde_dsi_probe,
1232	.remove_new = mcde_dsi_remove,
1233};
1234