1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * DesignWare MIPI DSI Host Controller v1.02 driver
4  *
5  * Copyright (c) 2016 Linaro Limited.
6  * Copyright (c) 2014-2016 Hisilicon Limited.
7  *
8  * Author:
9  *	Xinliang Liu <z.liuxinliang@hisilicon.com>
10  *	Xinliang Liu <xinliang.liu@linaro.org>
11  *	Xinwei Kong <kong.kongxinwei@hisilicon.com>
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/component.h>
16 #include <linux/delay.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 
20 #include <drm/drm_atomic_helper.h>
21 #include <drm/drm_bridge.h>
22 #include <drm/drm_device.h>
23 #include <drm/drm_mipi_dsi.h>
24 #include <drm/drm_of.h>
25 #include <drm/drm_print.h>
26 #include <drm/drm_probe_helper.h>
27 #include <drm/drm_simple_kms_helper.h>
28 
29 #include "dw_dsi_reg.h"
30 
31 #define MAX_TX_ESC_CLK		10
32 #define ROUND(x, y)		((x) / (y) + \
33 				((x) % (y) * 10 / (y) >= 5 ? 1 : 0))
34 #define PHY_REF_CLK_RATE	19200000
35 #define PHY_REF_CLK_PERIOD_PS	(1000000000 / (PHY_REF_CLK_RATE / 1000))
36 
37 #define encoder_to_dsi(encoder) \
38 	container_of(encoder, struct dw_dsi, encoder)
39 #define host_to_dsi(host) \
40 	container_of(host, struct dw_dsi, host)
41 
42 struct mipi_phy_params {
43 	u32 clk_t_lpx;
44 	u32 clk_t_hs_prepare;
45 	u32 clk_t_hs_zero;
46 	u32 clk_t_hs_trial;
47 	u32 clk_t_wakeup;
48 	u32 data_t_lpx;
49 	u32 data_t_hs_prepare;
50 	u32 data_t_hs_zero;
51 	u32 data_t_hs_trial;
52 	u32 data_t_ta_go;
53 	u32 data_t_ta_get;
54 	u32 data_t_wakeup;
55 	u32 hstx_ckg_sel;
56 	u32 pll_fbd_div5f;
57 	u32 pll_fbd_div1f;
58 	u32 pll_fbd_2p;
59 	u32 pll_enbwt;
60 	u32 pll_fbd_p;
61 	u32 pll_fbd_s;
62 	u32 pll_pre_div1p;
63 	u32 pll_pre_p;
64 	u32 pll_vco_750M;
65 	u32 pll_lpf_rs;
66 	u32 pll_lpf_cs;
67 	u32 clklp2hs_time;
68 	u32 clkhs2lp_time;
69 	u32 lp2hs_time;
70 	u32 hs2lp_time;
71 	u32 clk_to_data_delay;
72 	u32 data_to_clk_delay;
73 	u32 lane_byte_clk_kHz;
74 	u32 clk_division;
75 };
76 
77 struct dsi_hw_ctx {
78 	void __iomem *base;
79 	struct clk *pclk;
80 };
81 
82 struct dw_dsi {
83 	struct drm_encoder encoder;
84 	struct drm_bridge *bridge;
85 	struct mipi_dsi_host host;
86 	struct drm_display_mode cur_mode;
87 	struct dsi_hw_ctx *ctx;
88 	struct mipi_phy_params phy;
89 
90 	u32 lanes;
91 	enum mipi_dsi_pixel_format format;
92 	unsigned long mode_flags;
93 	bool enable;
94 };
95 
96 struct dsi_data {
97 	struct dw_dsi dsi;
98 	struct dsi_hw_ctx ctx;
99 };
100 
101 struct dsi_phy_range {
102 	u32 min_range_kHz;
103 	u32 max_range_kHz;
104 	u32 pll_vco_750M;
105 	u32 hstx_ckg_sel;
106 };
107 
108 static const struct dsi_phy_range dphy_range_info[] = {
109 	{   46875,    62500,   1,    7 },
110 	{   62500,    93750,   0,    7 },
111 	{   93750,   125000,   1,    6 },
112 	{  125000,   187500,   0,    6 },
113 	{  187500,   250000,   1,    5 },
114 	{  250000,   375000,   0,    5 },
115 	{  375000,   500000,   1,    4 },
116 	{  500000,   750000,   0,    4 },
117 	{  750000,  1000000,   1,    0 },
118 	{ 1000000,  1500000,   0,    0 }
119 };
120 
121 static u32 dsi_calc_phy_rate(u32 req_kHz, struct mipi_phy_params *phy)
122 {
123 	u32 ref_clk_ps = PHY_REF_CLK_PERIOD_PS;
124 	u32 tmp_kHz = req_kHz;
125 	u32 i = 0;
126 	u32 q_pll = 1;
127 	u32 m_pll = 0;
128 	u32 n_pll = 0;
129 	u32 r_pll = 1;
130 	u32 m_n = 0;
131 	u32 m_n_int = 0;
132 	u32 f_kHz = 0;
133 	u64 temp;
134 
135 	/*
136 	 * Find a rate >= req_kHz.
137 	 */
138 	do {
139 		f_kHz = tmp_kHz;
140 
141 		for (i = 0; i < ARRAY_SIZE(dphy_range_info); i++)
142 			if (f_kHz >= dphy_range_info[i].min_range_kHz &&
143 			    f_kHz <= dphy_range_info[i].max_range_kHz)
144 				break;
145 
146 		if (i == ARRAY_SIZE(dphy_range_info)) {
147 			DRM_ERROR("%dkHz out of range\n", f_kHz);
148 			return 0;
149 		}
150 
151 		phy->pll_vco_750M = dphy_range_info[i].pll_vco_750M;
152 		phy->hstx_ckg_sel = dphy_range_info[i].hstx_ckg_sel;
153 
154 		if (phy->hstx_ckg_sel <= 7 &&
155 		    phy->hstx_ckg_sel >= 4)
156 			q_pll = 0x10 >> (7 - phy->hstx_ckg_sel);
157 
158 		temp = f_kHz * (u64)q_pll * (u64)ref_clk_ps;
159 		m_n_int = temp / (u64)1000000000;
160 		m_n = (temp % (u64)1000000000) / (u64)100000000;
161 
162 		if (m_n_int % 2 == 0) {
163 			if (m_n * 6 >= 50) {
164 				n_pll = 2;
165 				m_pll = (m_n_int + 1) * n_pll;
166 			} else if (m_n * 6 >= 30) {
167 				n_pll = 3;
168 				m_pll = m_n_int * n_pll + 2;
169 			} else {
170 				n_pll = 1;
171 				m_pll = m_n_int * n_pll;
172 			}
173 		} else {
174 			if (m_n * 6 >= 50) {
175 				n_pll = 1;
176 				m_pll = (m_n_int + 1) * n_pll;
177 			} else if (m_n * 6 >= 30) {
178 				n_pll = 1;
179 				m_pll = (m_n_int + 1) * n_pll;
180 			} else if (m_n * 6 >= 10) {
181 				n_pll = 3;
182 				m_pll = m_n_int * n_pll + 1;
183 			} else {
184 				n_pll = 2;
185 				m_pll = m_n_int * n_pll;
186 			}
187 		}
188 
189 		if (n_pll == 1) {
190 			phy->pll_fbd_p = 0;
191 			phy->pll_pre_div1p = 1;
192 		} else {
193 			phy->pll_fbd_p = n_pll;
194 			phy->pll_pre_div1p = 0;
195 		}
196 
197 		if (phy->pll_fbd_2p <= 7 && phy->pll_fbd_2p >= 4)
198 			r_pll = 0x10 >> (7 - phy->pll_fbd_2p);
199 
200 		if (m_pll == 2) {
201 			phy->pll_pre_p = 0;
202 			phy->pll_fbd_s = 0;
203 			phy->pll_fbd_div1f = 0;
204 			phy->pll_fbd_div5f = 1;
205 		} else if (m_pll >= 2 * 2 * r_pll && m_pll <= 2 * 4 * r_pll) {
206 			phy->pll_pre_p = m_pll / (2 * r_pll);
207 			phy->pll_fbd_s = 0;
208 			phy->pll_fbd_div1f = 1;
209 			phy->pll_fbd_div5f = 0;
210 		} else if (m_pll >= 2 * 5 * r_pll && m_pll <= 2 * 150 * r_pll) {
211 			if (((m_pll / (2 * r_pll)) % 2) == 0) {
212 				phy->pll_pre_p =
213 					(m_pll / (2 * r_pll)) / 2 - 1;
214 				phy->pll_fbd_s =
215 					(m_pll / (2 * r_pll)) % 2 + 2;
216 			} else {
217 				phy->pll_pre_p =
218 					(m_pll / (2 * r_pll)) / 2;
219 				phy->pll_fbd_s =
220 					(m_pll / (2 * r_pll)) % 2;
221 			}
222 			phy->pll_fbd_div1f = 0;
223 			phy->pll_fbd_div5f = 0;
224 		} else {
225 			phy->pll_pre_p = 0;
226 			phy->pll_fbd_s = 0;
227 			phy->pll_fbd_div1f = 0;
228 			phy->pll_fbd_div5f = 1;
229 		}
230 
231 		f_kHz = (u64)1000000000 * (u64)m_pll /
232 			((u64)ref_clk_ps * (u64)n_pll * (u64)q_pll);
233 
234 		if (f_kHz >= req_kHz)
235 			break;
236 
237 		tmp_kHz += 10;
238 
239 	} while (true);
240 
241 	return f_kHz;
242 }
243 
244 static void dsi_get_phy_params(u32 phy_req_kHz,
245 			       struct mipi_phy_params *phy)
246 {
247 	u32 ref_clk_ps = PHY_REF_CLK_PERIOD_PS;
248 	u32 phy_rate_kHz;
249 	u32 ui;
250 
251 	memset(phy, 0, sizeof(*phy));
252 
253 	phy_rate_kHz = dsi_calc_phy_rate(phy_req_kHz, phy);
254 	if (!phy_rate_kHz)
255 		return;
256 
257 	ui = 1000000 / phy_rate_kHz;
258 
259 	phy->clk_t_lpx = ROUND(50, 8 * ui);
260 	phy->clk_t_hs_prepare = ROUND(133, 16 * ui) - 1;
261 
262 	phy->clk_t_hs_zero = ROUND(262, 8 * ui);
263 	phy->clk_t_hs_trial = 2 * (ROUND(60, 8 * ui) - 1);
264 	phy->clk_t_wakeup = ROUND(1000000, (ref_clk_ps / 1000) - 1);
265 	if (phy->clk_t_wakeup > 0xff)
266 		phy->clk_t_wakeup = 0xff;
267 	phy->data_t_wakeup = phy->clk_t_wakeup;
268 	phy->data_t_lpx = phy->clk_t_lpx;
269 	phy->data_t_hs_prepare = ROUND(125 + 10 * ui, 16 * ui) - 1;
270 	phy->data_t_hs_zero = ROUND(105 + 6 * ui, 8 * ui);
271 	phy->data_t_hs_trial = 2 * (ROUND(60 + 4 * ui, 8 * ui) - 1);
272 	phy->data_t_ta_go = 3;
273 	phy->data_t_ta_get = 4;
274 
275 	phy->pll_enbwt = 1;
276 	phy->clklp2hs_time = ROUND(407, 8 * ui) + 12;
277 	phy->clkhs2lp_time = ROUND(105 + 12 * ui, 8 * ui);
278 	phy->lp2hs_time = ROUND(240 + 12 * ui, 8 * ui) + 1;
279 	phy->hs2lp_time = phy->clkhs2lp_time;
280 	phy->clk_to_data_delay = 1 + phy->clklp2hs_time;
281 	phy->data_to_clk_delay = ROUND(60 + 52 * ui, 8 * ui) +
282 				phy->clkhs2lp_time;
283 
284 	phy->lane_byte_clk_kHz = phy_rate_kHz / 8;
285 	phy->clk_division =
286 		DIV_ROUND_UP(phy->lane_byte_clk_kHz, MAX_TX_ESC_CLK);
287 }
288 
289 static u32 dsi_get_dpi_color_coding(enum mipi_dsi_pixel_format format)
290 {
291 	u32 val;
292 
293 	/*
294 	 * TODO: only support RGB888 now, to support more
295 	 */
296 	switch (format) {
297 	case MIPI_DSI_FMT_RGB888:
298 		val = DSI_24BITS_1;
299 		break;
300 	default:
301 		val = DSI_24BITS_1;
302 		break;
303 	}
304 
305 	return val;
306 }
307 
308 /*
309  * dsi phy reg write function
310  */
311 static void dsi_phy_tst_set(void __iomem *base, u32 reg, u32 val)
312 {
313 	u32 reg_write = 0x10000 + reg;
314 
315 	/*
316 	 * latch reg first
317 	 */
318 	writel(reg_write, base + PHY_TST_CTRL1);
319 	writel(0x02, base + PHY_TST_CTRL0);
320 	writel(0x00, base + PHY_TST_CTRL0);
321 
322 	/*
323 	 * then latch value
324 	 */
325 	writel(val, base + PHY_TST_CTRL1);
326 	writel(0x02, base + PHY_TST_CTRL0);
327 	writel(0x00, base + PHY_TST_CTRL0);
328 }
329 
330 static void dsi_set_phy_timer(void __iomem *base,
331 			      struct mipi_phy_params *phy,
332 			      u32 lanes)
333 {
334 	u32 val;
335 
336 	/*
337 	 * Set lane value and phy stop wait time.
338 	 */
339 	val = (lanes - 1) | (PHY_STOP_WAIT_TIME << 8);
340 	writel(val, base + PHY_IF_CFG);
341 
342 	/*
343 	 * Set phy clk division.
344 	 */
345 	val = readl(base + CLKMGR_CFG) | phy->clk_division;
346 	writel(val, base + CLKMGR_CFG);
347 
348 	/*
349 	 * Set lp and hs switching params.
350 	 */
351 	dw_update_bits(base + PHY_TMR_CFG, 24, MASK(8), phy->hs2lp_time);
352 	dw_update_bits(base + PHY_TMR_CFG, 16, MASK(8), phy->lp2hs_time);
353 	dw_update_bits(base + PHY_TMR_LPCLK_CFG, 16, MASK(10),
354 		       phy->clkhs2lp_time);
355 	dw_update_bits(base + PHY_TMR_LPCLK_CFG, 0, MASK(10),
356 		       phy->clklp2hs_time);
357 	dw_update_bits(base + CLK_DATA_TMR_CFG, 8, MASK(8),
358 		       phy->data_to_clk_delay);
359 	dw_update_bits(base + CLK_DATA_TMR_CFG, 0, MASK(8),
360 		       phy->clk_to_data_delay);
361 }
362 
363 static void dsi_set_mipi_phy(void __iomem *base,
364 			     struct mipi_phy_params *phy,
365 			     u32 lanes)
366 {
367 	u32 delay_count;
368 	u32 val;
369 	u32 i;
370 
371 	/* phy timer setting */
372 	dsi_set_phy_timer(base, phy, lanes);
373 
374 	/*
375 	 * Reset to clean up phy tst params.
376 	 */
377 	writel(0, base + PHY_RSTZ);
378 	writel(0, base + PHY_TST_CTRL0);
379 	writel(1, base + PHY_TST_CTRL0);
380 	writel(0, base + PHY_TST_CTRL0);
381 
382 	/*
383 	 * Clock lane timing control setting: TLPX, THS-PREPARE,
384 	 * THS-ZERO, THS-TRAIL, TWAKEUP.
385 	 */
386 	dsi_phy_tst_set(base, CLK_TLPX, phy->clk_t_lpx);
387 	dsi_phy_tst_set(base, CLK_THS_PREPARE, phy->clk_t_hs_prepare);
388 	dsi_phy_tst_set(base, CLK_THS_ZERO, phy->clk_t_hs_zero);
389 	dsi_phy_tst_set(base, CLK_THS_TRAIL, phy->clk_t_hs_trial);
390 	dsi_phy_tst_set(base, CLK_TWAKEUP, phy->clk_t_wakeup);
391 
392 	/*
393 	 * Data lane timing control setting: TLPX, THS-PREPARE,
394 	 * THS-ZERO, THS-TRAIL, TTA-GO, TTA-GET, TWAKEUP.
395 	 */
396 	for (i = 0; i < lanes; i++) {
397 		dsi_phy_tst_set(base, DATA_TLPX(i), phy->data_t_lpx);
398 		dsi_phy_tst_set(base, DATA_THS_PREPARE(i),
399 				phy->data_t_hs_prepare);
400 		dsi_phy_tst_set(base, DATA_THS_ZERO(i), phy->data_t_hs_zero);
401 		dsi_phy_tst_set(base, DATA_THS_TRAIL(i), phy->data_t_hs_trial);
402 		dsi_phy_tst_set(base, DATA_TTA_GO(i), phy->data_t_ta_go);
403 		dsi_phy_tst_set(base, DATA_TTA_GET(i), phy->data_t_ta_get);
404 		dsi_phy_tst_set(base, DATA_TWAKEUP(i), phy->data_t_wakeup);
405 	}
406 
407 	/*
408 	 * physical configuration: I, pll I, pll II, pll III,
409 	 * pll IV, pll V.
410 	 */
411 	dsi_phy_tst_set(base, PHY_CFG_I, phy->hstx_ckg_sel);
412 	val = (phy->pll_fbd_div5f << 5) + (phy->pll_fbd_div1f << 4) +
413 				(phy->pll_fbd_2p << 1) + phy->pll_enbwt;
414 	dsi_phy_tst_set(base, PHY_CFG_PLL_I, val);
415 	dsi_phy_tst_set(base, PHY_CFG_PLL_II, phy->pll_fbd_p);
416 	dsi_phy_tst_set(base, PHY_CFG_PLL_III, phy->pll_fbd_s);
417 	val = (phy->pll_pre_div1p << 7) + phy->pll_pre_p;
418 	dsi_phy_tst_set(base, PHY_CFG_PLL_IV, val);
419 	val = (5 << 5) + (phy->pll_vco_750M << 4) + (phy->pll_lpf_rs << 2) +
420 		phy->pll_lpf_cs;
421 	dsi_phy_tst_set(base, PHY_CFG_PLL_V, val);
422 
423 	writel(PHY_ENABLECLK, base + PHY_RSTZ);
424 	udelay(1);
425 	writel(PHY_ENABLECLK | PHY_UNSHUTDOWNZ, base + PHY_RSTZ);
426 	udelay(1);
427 	writel(PHY_ENABLECLK | PHY_UNRSTZ | PHY_UNSHUTDOWNZ, base + PHY_RSTZ);
428 	usleep_range(1000, 1500);
429 
430 	/*
431 	 * wait for phy's clock ready
432 	 */
433 	delay_count = 100;
434 	while (delay_count) {
435 		val = readl(base +  PHY_STATUS);
436 		if ((BIT(0) | BIT(2)) & val)
437 			break;
438 
439 		udelay(1);
440 		delay_count--;
441 	}
442 
443 	if (!delay_count)
444 		DRM_INFO("phylock and phystopstateclklane is not ready.\n");
445 }
446 
447 static void dsi_set_mode_timing(void __iomem *base,
448 				u32 lane_byte_clk_kHz,
449 				struct drm_display_mode *mode,
450 				enum mipi_dsi_pixel_format format)
451 {
452 	u32 hfp, hbp, hsw, vfp, vbp, vsw;
453 	u32 hline_time;
454 	u32 hsa_time;
455 	u32 hbp_time;
456 	u32 pixel_clk_kHz;
457 	int htot, vtot;
458 	u32 val;
459 	u64 tmp;
460 
461 	val = dsi_get_dpi_color_coding(format);
462 	writel(val, base + DPI_COLOR_CODING);
463 
464 	val = (mode->flags & DRM_MODE_FLAG_NHSYNC ? 1 : 0) << 2;
465 	val |= (mode->flags & DRM_MODE_FLAG_NVSYNC ? 1 : 0) << 1;
466 	writel(val, base +  DPI_CFG_POL);
467 
468 	/*
469 	 * The DSI IP accepts vertical timing using lines as normal,
470 	 * but horizontal timing is a mixture of pixel-clocks for the
471 	 * active region and byte-lane clocks for the blanking-related
472 	 * timings.  hfp is specified as the total hline_time in byte-
473 	 * lane clocks minus hsa, hbp and active.
474 	 */
475 	pixel_clk_kHz = mode->clock;
476 	htot = mode->htotal;
477 	vtot = mode->vtotal;
478 	hfp = mode->hsync_start - mode->hdisplay;
479 	hbp = mode->htotal - mode->hsync_end;
480 	hsw = mode->hsync_end - mode->hsync_start;
481 	vfp = mode->vsync_start - mode->vdisplay;
482 	vbp = mode->vtotal - mode->vsync_end;
483 	vsw = mode->vsync_end - mode->vsync_start;
484 	if (vsw > 15) {
485 		DRM_DEBUG_DRIVER("vsw exceeded 15\n");
486 		vsw = 15;
487 	}
488 
489 	hsa_time = (hsw * lane_byte_clk_kHz) / pixel_clk_kHz;
490 	hbp_time = (hbp * lane_byte_clk_kHz) / pixel_clk_kHz;
491 	tmp = (u64)htot * (u64)lane_byte_clk_kHz;
492 	hline_time = DIV_ROUND_UP(tmp, pixel_clk_kHz);
493 
494 	/* all specified in byte-lane clocks */
495 	writel(hsa_time, base + VID_HSA_TIME);
496 	writel(hbp_time, base + VID_HBP_TIME);
497 	writel(hline_time, base + VID_HLINE_TIME);
498 
499 	writel(vsw, base + VID_VSA_LINES);
500 	writel(vbp, base + VID_VBP_LINES);
501 	writel(vfp, base + VID_VFP_LINES);
502 	writel(mode->vdisplay, base + VID_VACTIVE_LINES);
503 	writel(mode->hdisplay, base + VID_PKT_SIZE);
504 
505 	DRM_DEBUG_DRIVER("htot=%d, hfp=%d, hbp=%d, hsw=%d\n",
506 			 htot, hfp, hbp, hsw);
507 	DRM_DEBUG_DRIVER("vtol=%d, vfp=%d, vbp=%d, vsw=%d\n",
508 			 vtot, vfp, vbp, vsw);
509 	DRM_DEBUG_DRIVER("hsa_time=%d, hbp_time=%d, hline_time=%d\n",
510 			 hsa_time, hbp_time, hline_time);
511 }
512 
513 static void dsi_set_video_mode(void __iomem *base, unsigned long flags)
514 {
515 	u32 val;
516 	u32 mode_mask = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
517 		MIPI_DSI_MODE_VIDEO_SYNC_PULSE;
518 	u32 non_burst_sync_pulse = MIPI_DSI_MODE_VIDEO |
519 		MIPI_DSI_MODE_VIDEO_SYNC_PULSE;
520 	u32 non_burst_sync_event = MIPI_DSI_MODE_VIDEO;
521 
522 	/*
523 	 * choose video mode type
524 	 */
525 	if ((flags & mode_mask) == non_burst_sync_pulse)
526 		val = DSI_NON_BURST_SYNC_PULSES;
527 	else if ((flags & mode_mask) == non_burst_sync_event)
528 		val = DSI_NON_BURST_SYNC_EVENTS;
529 	else
530 		val = DSI_BURST_SYNC_PULSES_1;
531 	writel(val, base + VID_MODE_CFG);
532 
533 	writel(PHY_TXREQUESTCLKHS, base + LPCLK_CTRL);
534 	writel(DSI_VIDEO_MODE, base + MODE_CFG);
535 }
536 
537 static void dsi_mipi_init(struct dw_dsi *dsi)
538 {
539 	struct dsi_hw_ctx *ctx = dsi->ctx;
540 	struct mipi_phy_params *phy = &dsi->phy;
541 	struct drm_display_mode *mode = &dsi->cur_mode;
542 	u32 bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
543 	void __iomem *base = ctx->base;
544 	u32 dphy_req_kHz;
545 
546 	/*
547 	 * count phy params
548 	 */
549 	dphy_req_kHz = mode->clock * bpp / dsi->lanes;
550 	dsi_get_phy_params(dphy_req_kHz, phy);
551 
552 	/* reset Core */
553 	writel(RESET, base + PWR_UP);
554 
555 	/* set dsi phy params */
556 	dsi_set_mipi_phy(base, phy, dsi->lanes);
557 
558 	/* set dsi mode timing */
559 	dsi_set_mode_timing(base, phy->lane_byte_clk_kHz, mode, dsi->format);
560 
561 	/* set dsi video mode */
562 	dsi_set_video_mode(base, dsi->mode_flags);
563 
564 	/* dsi wake up */
565 	writel(POWERUP, base + PWR_UP);
566 
567 	DRM_DEBUG_DRIVER("lanes=%d, pixel_clk=%d kHz, bytes_freq=%d kHz\n",
568 			 dsi->lanes, mode->clock, phy->lane_byte_clk_kHz);
569 }
570 
571 static void dsi_encoder_disable(struct drm_encoder *encoder)
572 {
573 	struct dw_dsi *dsi = encoder_to_dsi(encoder);
574 	struct dsi_hw_ctx *ctx = dsi->ctx;
575 	void __iomem *base = ctx->base;
576 
577 	if (!dsi->enable)
578 		return;
579 
580 	writel(0, base + PWR_UP);
581 	writel(0, base + LPCLK_CTRL);
582 	writel(0, base + PHY_RSTZ);
583 	clk_disable_unprepare(ctx->pclk);
584 
585 	dsi->enable = false;
586 }
587 
588 static void dsi_encoder_enable(struct drm_encoder *encoder)
589 {
590 	struct dw_dsi *dsi = encoder_to_dsi(encoder);
591 	struct dsi_hw_ctx *ctx = dsi->ctx;
592 	int ret;
593 
594 	if (dsi->enable)
595 		return;
596 
597 	ret = clk_prepare_enable(ctx->pclk);
598 	if (ret) {
599 		DRM_ERROR("fail to enable pclk: %d\n", ret);
600 		return;
601 	}
602 
603 	dsi_mipi_init(dsi);
604 
605 	dsi->enable = true;
606 }
607 
608 static enum drm_mode_status dsi_encoder_phy_mode_valid(
609 					struct drm_encoder *encoder,
610 					const struct drm_display_mode *mode)
611 {
612 	struct dw_dsi *dsi = encoder_to_dsi(encoder);
613 	struct mipi_phy_params phy;
614 	u32 bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
615 	u32 req_kHz, act_kHz, lane_byte_clk_kHz;
616 
617 	/* Calculate the lane byte clk using the adjusted mode clk */
618 	memset(&phy, 0, sizeof(phy));
619 	req_kHz = mode->clock * bpp / dsi->lanes;
620 	act_kHz = dsi_calc_phy_rate(req_kHz, &phy);
621 	lane_byte_clk_kHz = act_kHz / 8;
622 
623 	DRM_DEBUG_DRIVER("Checking mode %ix%i-%i@%i clock: %i...",
624 			mode->hdisplay, mode->vdisplay, bpp,
625 			drm_mode_vrefresh(mode), mode->clock);
626 
627 	/*
628 	 * Make sure the adjusted mode clock and the lane byte clk
629 	 * have a common denominator base frequency
630 	 */
631 	if (mode->clock/dsi->lanes == lane_byte_clk_kHz/3) {
632 		DRM_DEBUG_DRIVER("OK!\n");
633 		return MODE_OK;
634 	}
635 
636 	DRM_DEBUG_DRIVER("BAD!\n");
637 	return MODE_BAD;
638 }
639 
640 static enum drm_mode_status dsi_encoder_mode_valid(struct drm_encoder *encoder,
641 					const struct drm_display_mode *mode)
642 
643 {
644 	const struct drm_crtc_helper_funcs *crtc_funcs = NULL;
645 	struct drm_crtc *crtc = NULL;
646 	struct drm_display_mode adj_mode;
647 	enum drm_mode_status ret;
648 
649 	/*
650 	 * The crtc might adjust the mode, so go through the
651 	 * possible crtcs (technically just one) and call
652 	 * mode_fixup to figure out the adjusted mode before we
653 	 * validate it.
654 	 */
655 	drm_for_each_crtc(crtc, encoder->dev) {
656 		/*
657 		 * reset adj_mode to the mode value each time,
658 		 * so we don't adjust the mode twice
659 		 */
660 		drm_mode_copy(&adj_mode, mode);
661 
662 		crtc_funcs = crtc->helper_private;
663 		if (crtc_funcs && crtc_funcs->mode_fixup)
664 			if (!crtc_funcs->mode_fixup(crtc, mode, &adj_mode))
665 				return MODE_BAD;
666 
667 		ret = dsi_encoder_phy_mode_valid(encoder, &adj_mode);
668 		if (ret != MODE_OK)
669 			return ret;
670 	}
671 	return MODE_OK;
672 }
673 
674 static void dsi_encoder_mode_set(struct drm_encoder *encoder,
675 				 struct drm_display_mode *mode,
676 				 struct drm_display_mode *adj_mode)
677 {
678 	struct dw_dsi *dsi = encoder_to_dsi(encoder);
679 
680 	drm_mode_copy(&dsi->cur_mode, adj_mode);
681 }
682 
683 static int dsi_encoder_atomic_check(struct drm_encoder *encoder,
684 				    struct drm_crtc_state *crtc_state,
685 				    struct drm_connector_state *conn_state)
686 {
687 	/* do nothing */
688 	return 0;
689 }
690 
691 static const struct drm_encoder_helper_funcs dw_encoder_helper_funcs = {
692 	.atomic_check	= dsi_encoder_atomic_check,
693 	.mode_valid	= dsi_encoder_mode_valid,
694 	.mode_set	= dsi_encoder_mode_set,
695 	.enable		= dsi_encoder_enable,
696 	.disable	= dsi_encoder_disable
697 };
698 
699 static int dw_drm_encoder_init(struct device *dev,
700 			       struct drm_device *drm_dev,
701 			       struct drm_encoder *encoder)
702 {
703 	int ret;
704 	u32 crtc_mask = drm_of_find_possible_crtcs(drm_dev, dev->of_node);
705 
706 	if (!crtc_mask) {
707 		DRM_ERROR("failed to find crtc mask\n");
708 		return -EINVAL;
709 	}
710 
711 	encoder->possible_crtcs = crtc_mask;
712 	ret = drm_simple_encoder_init(drm_dev, encoder, DRM_MODE_ENCODER_DSI);
713 	if (ret) {
714 		DRM_ERROR("failed to init dsi encoder\n");
715 		return ret;
716 	}
717 
718 	drm_encoder_helper_add(encoder, &dw_encoder_helper_funcs);
719 
720 	return 0;
721 }
722 
723 static int dsi_host_attach(struct mipi_dsi_host *host,
724 			   struct mipi_dsi_device *mdsi)
725 {
726 	struct dw_dsi *dsi = host_to_dsi(host);
727 
728 	if (mdsi->lanes < 1 || mdsi->lanes > 4) {
729 		DRM_ERROR("dsi device params invalid\n");
730 		return -EINVAL;
731 	}
732 
733 	dsi->lanes = mdsi->lanes;
734 	dsi->format = mdsi->format;
735 	dsi->mode_flags = mdsi->mode_flags;
736 
737 	return 0;
738 }
739 
740 static int dsi_host_detach(struct mipi_dsi_host *host,
741 			   struct mipi_dsi_device *mdsi)
742 {
743 	/* do nothing */
744 	return 0;
745 }
746 
747 static const struct mipi_dsi_host_ops dsi_host_ops = {
748 	.attach = dsi_host_attach,
749 	.detach = dsi_host_detach,
750 };
751 
752 static int dsi_host_init(struct device *dev, struct dw_dsi *dsi)
753 {
754 	struct mipi_dsi_host *host = &dsi->host;
755 	int ret;
756 
757 	host->dev = dev;
758 	host->ops = &dsi_host_ops;
759 	ret = mipi_dsi_host_register(host);
760 	if (ret) {
761 		DRM_ERROR("failed to register dsi host\n");
762 		return ret;
763 	}
764 
765 	return 0;
766 }
767 
768 static int dsi_bridge_init(struct drm_device *dev, struct dw_dsi *dsi)
769 {
770 	struct drm_encoder *encoder = &dsi->encoder;
771 	struct drm_bridge *bridge = dsi->bridge;
772 	int ret;
773 
774 	/* associate the bridge to dsi encoder */
775 	ret = drm_bridge_attach(encoder, bridge, NULL, 0);
776 	if (ret) {
777 		DRM_ERROR("failed to attach external bridge\n");
778 		return ret;
779 	}
780 
781 	return 0;
782 }
783 
784 static int dsi_bind(struct device *dev, struct device *master, void *data)
785 {
786 	struct dsi_data *ddata = dev_get_drvdata(dev);
787 	struct dw_dsi *dsi = &ddata->dsi;
788 	struct drm_device *drm_dev = data;
789 	int ret;
790 
791 	ret = dw_drm_encoder_init(dev, drm_dev, &dsi->encoder);
792 	if (ret)
793 		return ret;
794 
795 	ret = dsi_host_init(dev, dsi);
796 	if (ret)
797 		return ret;
798 
799 	ret = dsi_bridge_init(drm_dev, dsi);
800 	if (ret)
801 		return ret;
802 
803 	return 0;
804 }
805 
806 static void dsi_unbind(struct device *dev, struct device *master, void *data)
807 {
808 	/* do nothing */
809 }
810 
811 static const struct component_ops dsi_ops = {
812 	.bind	= dsi_bind,
813 	.unbind	= dsi_unbind,
814 };
815 
816 static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi)
817 {
818 	struct dsi_hw_ctx *ctx = dsi->ctx;
819 	struct device_node *np = pdev->dev.of_node;
820 	struct resource *res;
821 	int ret;
822 
823 	/*
824 	 * Get the endpoint node. In our case, dsi has one output port1
825 	 * to which the external HDMI bridge is connected.
826 	 */
827 	ret = drm_of_find_panel_or_bridge(np, 1, 0, NULL, &dsi->bridge);
828 	if (ret)
829 		return ret;
830 
831 	ctx->pclk = devm_clk_get(&pdev->dev, "pclk");
832 	if (IS_ERR(ctx->pclk)) {
833 		DRM_ERROR("failed to get pclk clock\n");
834 		return PTR_ERR(ctx->pclk);
835 	}
836 
837 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
838 	ctx->base = devm_ioremap_resource(&pdev->dev, res);
839 	if (IS_ERR(ctx->base)) {
840 		DRM_ERROR("failed to remap dsi io region\n");
841 		return PTR_ERR(ctx->base);
842 	}
843 
844 	return 0;
845 }
846 
847 static int dsi_probe(struct platform_device *pdev)
848 {
849 	struct dsi_data *data;
850 	struct dw_dsi *dsi;
851 	struct dsi_hw_ctx *ctx;
852 	int ret;
853 
854 	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
855 	if (!data) {
856 		DRM_ERROR("failed to allocate dsi data.\n");
857 		return -ENOMEM;
858 	}
859 	dsi = &data->dsi;
860 	ctx = &data->ctx;
861 	dsi->ctx = ctx;
862 
863 	ret = dsi_parse_dt(pdev, dsi);
864 	if (ret)
865 		return ret;
866 
867 	platform_set_drvdata(pdev, data);
868 
869 	return component_add(&pdev->dev, &dsi_ops);
870 }
871 
872 static int dsi_remove(struct platform_device *pdev)
873 {
874 	component_del(&pdev->dev, &dsi_ops);
875 
876 	return 0;
877 }
878 
879 static const struct of_device_id dsi_of_match[] = {
880 	{.compatible = "hisilicon,hi6220-dsi"},
881 	{ }
882 };
883 MODULE_DEVICE_TABLE(of, dsi_of_match);
884 
885 static struct platform_driver dsi_driver = {
886 	.probe = dsi_probe,
887 	.remove = dsi_remove,
888 	.driver = {
889 		.name = "dw-dsi",
890 		.of_match_table = dsi_of_match,
891 	},
892 };
893 
894 module_platform_driver(dsi_driver);
895 
896 MODULE_AUTHOR("Xinliang Liu <xinliang.liu@linaro.org>");
897 MODULE_AUTHOR("Xinliang Liu <z.liuxinliang@hisilicon.com>");
898 MODULE_AUTHOR("Xinwei Kong <kong.kongxinwei@hisilicon.com>");
899 MODULE_DESCRIPTION("DesignWare MIPI DSI Host Controller v1.02 driver");
900 MODULE_LICENSE("GPL v2");
901