1 /*
2  * Copyright © 2013 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21  * DEALINGS IN THE SOFTWARE.
22  *
23  * Authors:
24  *	Shobhit Kumar <shobhit.kumar@intel.com>
25  *	Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
26  */
27 
28 #include <linux/kernel.h>
29 
30 #include "i915_drv.h"
31 #include "intel_de.h"
32 #include "intel_display_types.h"
33 #include "intel_dsi.h"
34 #include "vlv_dsi_pll.h"
35 #include "vlv_sideband.h"
36 
37 static const u16 lfsr_converts[] = {
38 	426, 469, 234, 373, 442, 221, 110, 311, 411,		/* 62 - 70 */
39 	461, 486, 243, 377, 188, 350, 175, 343, 427, 213,	/* 71 - 80 */
40 	106, 53, 282, 397, 454, 227, 113, 56, 284, 142,		/* 81 - 90 */
41 	71, 35, 273, 136, 324, 418, 465, 488, 500, 506		/* 91 - 100 */
42 };
43 
44 /* Get DSI clock from pixel clock */
45 static u32 dsi_clk_from_pclk(u32 pclk, enum mipi_dsi_pixel_format fmt,
46 			     int lane_count)
47 {
48 	u32 dsi_clk_khz;
49 	u32 bpp = mipi_dsi_pixel_format_to_bpp(fmt);
50 
51 	/* DSI data rate = pixel clock * bits per pixel / lane count
52 	   pixel clock is converted from KHz to Hz */
53 	dsi_clk_khz = DIV_ROUND_CLOSEST(pclk * bpp, lane_count);
54 
55 	return dsi_clk_khz;
56 }
57 
58 static int dsi_calc_mnp(struct drm_i915_private *dev_priv,
59 			struct intel_crtc_state *config,
60 			int target_dsi_clk)
61 {
62 	unsigned int m_min, m_max, p_min = 2, p_max = 6;
63 	unsigned int m, n, p;
64 	unsigned int calc_m, calc_p;
65 	int delta, ref_clk;
66 
67 	/* target_dsi_clk is expected in kHz */
68 	if (target_dsi_clk < 300000 || target_dsi_clk > 1150000) {
69 		drm_err(&dev_priv->drm, "DSI CLK Out of Range\n");
70 		return -ECHRNG;
71 	}
72 
73 	if (IS_CHERRYVIEW(dev_priv)) {
74 		ref_clk = 100000;
75 		n = 4;
76 		m_min = 70;
77 		m_max = 96;
78 	} else {
79 		ref_clk = 25000;
80 		n = 1;
81 		m_min = 62;
82 		m_max = 92;
83 	}
84 
85 	calc_p = p_min;
86 	calc_m = m_min;
87 	delta = abs(target_dsi_clk - (m_min * ref_clk) / (p_min * n));
88 
89 	for (m = m_min; m <= m_max && delta; m++) {
90 		for (p = p_min; p <= p_max && delta; p++) {
91 			/*
92 			 * Find the optimal m and p divisors with minimal delta
93 			 * +/- the required clock
94 			 */
95 			int calc_dsi_clk = (m * ref_clk) / (p * n);
96 			int d = abs(target_dsi_clk - calc_dsi_clk);
97 			if (d < delta) {
98 				delta = d;
99 				calc_m = m;
100 				calc_p = p;
101 			}
102 		}
103 	}
104 
105 	/* register has log2(N1), this works fine for powers of two */
106 	config->dsi_pll.ctrl = 1 << (DSI_PLL_P1_POST_DIV_SHIFT + calc_p - 2);
107 	config->dsi_pll.div =
108 		(ffs(n) - 1) << DSI_PLL_N1_DIV_SHIFT |
109 		(u32)lfsr_converts[calc_m - 62] << DSI_PLL_M1_DIV_SHIFT;
110 
111 	return 0;
112 }
113 
114 /*
115  * XXX: The muxing and gating is hard coded for now. Need to add support for
116  * sharing PLLs with two DSI outputs.
117  */
118 int vlv_dsi_pll_compute(struct intel_encoder *encoder,
119 			struct intel_crtc_state *config)
120 {
121 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
122 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
123 	int ret;
124 	u32 dsi_clk;
125 
126 	dsi_clk = dsi_clk_from_pclk(intel_dsi->pclk, intel_dsi->pixel_format,
127 				    intel_dsi->lane_count);
128 
129 	ret = dsi_calc_mnp(dev_priv, config, dsi_clk);
130 	if (ret) {
131 		drm_dbg_kms(&dev_priv->drm, "dsi_calc_mnp failed\n");
132 		return ret;
133 	}
134 
135 	if (intel_dsi->ports & (1 << PORT_A))
136 		config->dsi_pll.ctrl |= DSI_PLL_CLK_GATE_DSI0_DSIPLL;
137 
138 	if (intel_dsi->ports & (1 << PORT_C))
139 		config->dsi_pll.ctrl |= DSI_PLL_CLK_GATE_DSI1_DSIPLL;
140 
141 	config->dsi_pll.ctrl |= DSI_PLL_VCO_EN;
142 
143 	drm_dbg_kms(&dev_priv->drm, "dsi pll div %08x, ctrl %08x\n",
144 		    config->dsi_pll.div, config->dsi_pll.ctrl);
145 
146 	return 0;
147 }
148 
149 void vlv_dsi_pll_enable(struct intel_encoder *encoder,
150 			const struct intel_crtc_state *config)
151 {
152 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
153 
154 	drm_dbg_kms(&dev_priv->drm, "\n");
155 
156 	vlv_cck_get(dev_priv);
157 
158 	vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, 0);
159 	vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_DIVIDER, config->dsi_pll.div);
160 	vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL,
161 		      config->dsi_pll.ctrl & ~DSI_PLL_VCO_EN);
162 
163 	/* wait at least 0.5 us after ungating before enabling VCO,
164 	 * allow hrtimer subsystem optimization by relaxing timing
165 	 */
166 	usleep_range(10, 50);
167 
168 	vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, config->dsi_pll.ctrl);
169 
170 	if (wait_for(vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_CONTROL) &
171 						DSI_PLL_LOCK, 20)) {
172 
173 		vlv_cck_put(dev_priv);
174 		drm_err(&dev_priv->drm, "DSI PLL lock failed\n");
175 		return;
176 	}
177 	vlv_cck_put(dev_priv);
178 
179 	drm_dbg_kms(&dev_priv->drm, "DSI PLL locked\n");
180 }
181 
182 void vlv_dsi_pll_disable(struct intel_encoder *encoder)
183 {
184 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
185 	u32 tmp;
186 
187 	drm_dbg_kms(&dev_priv->drm, "\n");
188 
189 	vlv_cck_get(dev_priv);
190 
191 	tmp = vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_CONTROL);
192 	tmp &= ~DSI_PLL_VCO_EN;
193 	tmp |= DSI_PLL_LDO_GATE;
194 	vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, tmp);
195 
196 	vlv_cck_put(dev_priv);
197 }
198 
199 bool bxt_dsi_pll_is_enabled(struct drm_i915_private *dev_priv)
200 {
201 	bool enabled;
202 	u32 val;
203 	u32 mask;
204 
205 	mask = BXT_DSI_PLL_DO_ENABLE | BXT_DSI_PLL_LOCKED;
206 	val = intel_de_read(dev_priv, BXT_DSI_PLL_ENABLE);
207 	enabled = (val & mask) == mask;
208 
209 	if (!enabled)
210 		return false;
211 
212 	/*
213 	 * Dividers must be programmed with valid values. As per BSEPC, for
214 	 * GEMINLAKE only PORT A divider values are checked while for BXT
215 	 * both divider values are validated. Check this here for
216 	 * paranoia, since BIOS is known to misconfigure PLLs in this way at
217 	 * times, and since accessing DSI registers with invalid dividers
218 	 * causes a system hang.
219 	 */
220 	val = intel_de_read(dev_priv, BXT_DSI_PLL_CTL);
221 	if (IS_GEMINILAKE(dev_priv)) {
222 		if (!(val & BXT_DSIA_16X_MASK)) {
223 			drm_dbg(&dev_priv->drm,
224 				"Invalid PLL divider (%08x)\n", val);
225 			enabled = false;
226 		}
227 	} else {
228 		if (!(val & BXT_DSIA_16X_MASK) || !(val & BXT_DSIC_16X_MASK)) {
229 			drm_dbg(&dev_priv->drm,
230 				"Invalid PLL divider (%08x)\n", val);
231 			enabled = false;
232 		}
233 	}
234 
235 	return enabled;
236 }
237 
238 void bxt_dsi_pll_disable(struct intel_encoder *encoder)
239 {
240 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
241 	u32 val;
242 
243 	drm_dbg_kms(&dev_priv->drm, "\n");
244 
245 	val = intel_de_read(dev_priv, BXT_DSI_PLL_ENABLE);
246 	val &= ~BXT_DSI_PLL_DO_ENABLE;
247 	intel_de_write(dev_priv, BXT_DSI_PLL_ENABLE, val);
248 
249 	/*
250 	 * PLL lock should deassert within 200us.
251 	 * Wait up to 1ms before timing out.
252 	 */
253 	if (intel_de_wait_for_clear(dev_priv, BXT_DSI_PLL_ENABLE,
254 				    BXT_DSI_PLL_LOCKED, 1))
255 		drm_err(&dev_priv->drm,
256 			"Timeout waiting for PLL lock deassertion\n");
257 }
258 
259 u32 vlv_dsi_get_pclk(struct intel_encoder *encoder,
260 		     struct intel_crtc_state *config)
261 {
262 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
263 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
264 	int bpp = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
265 	u32 dsi_clock, pclk;
266 	u32 pll_ctl, pll_div;
267 	u32 m = 0, p = 0, n;
268 	int refclk = IS_CHERRYVIEW(dev_priv) ? 100000 : 25000;
269 	int i;
270 
271 	drm_dbg_kms(&dev_priv->drm, "\n");
272 
273 	vlv_cck_get(dev_priv);
274 	pll_ctl = vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_CONTROL);
275 	pll_div = vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_DIVIDER);
276 	vlv_cck_put(dev_priv);
277 
278 	config->dsi_pll.ctrl = pll_ctl & ~DSI_PLL_LOCK;
279 	config->dsi_pll.div = pll_div;
280 
281 	/* mask out other bits and extract the P1 divisor */
282 	pll_ctl &= DSI_PLL_P1_POST_DIV_MASK;
283 	pll_ctl = pll_ctl >> (DSI_PLL_P1_POST_DIV_SHIFT - 2);
284 
285 	/* N1 divisor */
286 	n = (pll_div & DSI_PLL_N1_DIV_MASK) >> DSI_PLL_N1_DIV_SHIFT;
287 	n = 1 << n; /* register has log2(N1) */
288 
289 	/* mask out the other bits and extract the M1 divisor */
290 	pll_div &= DSI_PLL_M1_DIV_MASK;
291 	pll_div = pll_div >> DSI_PLL_M1_DIV_SHIFT;
292 
293 	while (pll_ctl) {
294 		pll_ctl = pll_ctl >> 1;
295 		p++;
296 	}
297 	p--;
298 
299 	if (!p) {
300 		drm_err(&dev_priv->drm, "wrong P1 divisor\n");
301 		return 0;
302 	}
303 
304 	for (i = 0; i < ARRAY_SIZE(lfsr_converts); i++) {
305 		if (lfsr_converts[i] == pll_div)
306 			break;
307 	}
308 
309 	if (i == ARRAY_SIZE(lfsr_converts)) {
310 		drm_err(&dev_priv->drm, "wrong m_seed programmed\n");
311 		return 0;
312 	}
313 
314 	m = i + 62;
315 
316 	dsi_clock = (m * refclk) / (p * n);
317 
318 	pclk = DIV_ROUND_CLOSEST(dsi_clock * intel_dsi->lane_count, bpp);
319 
320 	return pclk;
321 }
322 
323 u32 bxt_dsi_get_pclk(struct intel_encoder *encoder,
324 		     struct intel_crtc_state *config)
325 {
326 	u32 pclk;
327 	u32 dsi_clk;
328 	u32 dsi_ratio;
329 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
330 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
331 	int bpp = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
332 
333 	config->dsi_pll.ctrl = intel_de_read(dev_priv, BXT_DSI_PLL_CTL);
334 
335 	dsi_ratio = config->dsi_pll.ctrl & BXT_DSI_PLL_RATIO_MASK;
336 
337 	dsi_clk = (dsi_ratio * BXT_REF_CLOCK_KHZ) / 2;
338 
339 	pclk = DIV_ROUND_CLOSEST(dsi_clk * intel_dsi->lane_count, bpp);
340 
341 	drm_dbg(&dev_priv->drm, "Calculated pclk=%u\n", pclk);
342 	return pclk;
343 }
344 
345 void vlv_dsi_reset_clocks(struct intel_encoder *encoder, enum port port)
346 {
347 	u32 temp;
348 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
349 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
350 
351 	temp = intel_de_read(dev_priv, MIPI_CTRL(port));
352 	temp &= ~ESCAPE_CLOCK_DIVIDER_MASK;
353 	intel_de_write(dev_priv, MIPI_CTRL(port),
354 		       temp | intel_dsi->escape_clk_div << ESCAPE_CLOCK_DIVIDER_SHIFT);
355 }
356 
357 static void glk_dsi_program_esc_clock(struct drm_device *dev,
358 				   const struct intel_crtc_state *config)
359 {
360 	struct drm_i915_private *dev_priv = to_i915(dev);
361 	u32 dsi_rate = 0;
362 	u32 pll_ratio = 0;
363 	u32 ddr_clk = 0;
364 	u32 div1_value = 0;
365 	u32 div2_value = 0;
366 	u32 txesc1_div = 0;
367 	u32 txesc2_div = 0;
368 
369 	pll_ratio = config->dsi_pll.ctrl & BXT_DSI_PLL_RATIO_MASK;
370 
371 	dsi_rate = (BXT_REF_CLOCK_KHZ * pll_ratio) / 2;
372 
373 	ddr_clk = dsi_rate / 2;
374 
375 	/* Variable divider value */
376 	div1_value = DIV_ROUND_CLOSEST(ddr_clk, 20000);
377 
378 	/* Calculate TXESC1 divider */
379 	if (div1_value <= 10)
380 		txesc1_div = div1_value;
381 	else if ((div1_value > 10) && (div1_value <= 20))
382 		txesc1_div = DIV_ROUND_UP(div1_value, 2);
383 	else if ((div1_value > 20) && (div1_value <= 30))
384 		txesc1_div = DIV_ROUND_UP(div1_value, 4);
385 	else if ((div1_value > 30) && (div1_value <= 40))
386 		txesc1_div = DIV_ROUND_UP(div1_value, 6);
387 	else if ((div1_value > 40) && (div1_value <= 50))
388 		txesc1_div = DIV_ROUND_UP(div1_value, 8);
389 	else
390 		txesc1_div = 10;
391 
392 	/* Calculate TXESC2 divider */
393 	div2_value = DIV_ROUND_UP(div1_value, txesc1_div);
394 
395 	if (div2_value < 10)
396 		txesc2_div = div2_value;
397 	else
398 		txesc2_div = 10;
399 
400 	intel_de_write(dev_priv, MIPIO_TXESC_CLK_DIV1,
401 		       (1 << (txesc1_div - 1)) & GLK_TX_ESC_CLK_DIV1_MASK);
402 	intel_de_write(dev_priv, MIPIO_TXESC_CLK_DIV2,
403 		       (1 << (txesc2_div - 1)) & GLK_TX_ESC_CLK_DIV2_MASK);
404 }
405 
406 /* Program BXT Mipi clocks and dividers */
407 static void bxt_dsi_program_clocks(struct drm_device *dev, enum port port,
408 				   const struct intel_crtc_state *config)
409 {
410 	struct drm_i915_private *dev_priv = to_i915(dev);
411 	u32 tmp;
412 	u32 dsi_rate = 0;
413 	u32 pll_ratio = 0;
414 	u32 rx_div;
415 	u32 tx_div;
416 	u32 rx_div_upper;
417 	u32 rx_div_lower;
418 	u32 mipi_8by3_divider;
419 
420 	/* Clear old configurations */
421 	tmp = intel_de_read(dev_priv, BXT_MIPI_CLOCK_CTL);
422 	tmp &= ~(BXT_MIPI_TX_ESCLK_FIXDIV_MASK(port));
423 	tmp &= ~(BXT_MIPI_RX_ESCLK_UPPER_FIXDIV_MASK(port));
424 	tmp &= ~(BXT_MIPI_8X_BY3_DIVIDER_MASK(port));
425 	tmp &= ~(BXT_MIPI_RX_ESCLK_LOWER_FIXDIV_MASK(port));
426 
427 	/* Get the current DSI rate(actual) */
428 	pll_ratio = config->dsi_pll.ctrl & BXT_DSI_PLL_RATIO_MASK;
429 	dsi_rate = (BXT_REF_CLOCK_KHZ * pll_ratio) / 2;
430 
431 	/*
432 	 * tx clock should be <= 20MHz and the div value must be
433 	 * subtracted by 1 as per bspec
434 	 */
435 	tx_div = DIV_ROUND_UP(dsi_rate, 20000) - 1;
436 	/*
437 	 * rx clock should be <= 150MHz and the div value must be
438 	 * subtracted by 1 as per bspec
439 	 */
440 	rx_div = DIV_ROUND_UP(dsi_rate, 150000) - 1;
441 
442 	/*
443 	 * rx divider value needs to be updated in the
444 	 * two differnt bit fields in the register hence splitting the
445 	 * rx divider value accordingly
446 	 */
447 	rx_div_lower = rx_div & RX_DIVIDER_BIT_1_2;
448 	rx_div_upper = (rx_div & RX_DIVIDER_BIT_3_4) >> 2;
449 
450 	mipi_8by3_divider = 0x2;
451 
452 	tmp |= BXT_MIPI_8X_BY3_DIVIDER(port, mipi_8by3_divider);
453 	tmp |= BXT_MIPI_TX_ESCLK_DIVIDER(port, tx_div);
454 	tmp |= BXT_MIPI_RX_ESCLK_LOWER_DIVIDER(port, rx_div_lower);
455 	tmp |= BXT_MIPI_RX_ESCLK_UPPER_DIVIDER(port, rx_div_upper);
456 
457 	intel_de_write(dev_priv, BXT_MIPI_CLOCK_CTL, tmp);
458 }
459 
460 int bxt_dsi_pll_compute(struct intel_encoder *encoder,
461 			struct intel_crtc_state *config)
462 {
463 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
464 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
465 	u8 dsi_ratio, dsi_ratio_min, dsi_ratio_max;
466 	u32 dsi_clk;
467 
468 	dsi_clk = dsi_clk_from_pclk(intel_dsi->pclk, intel_dsi->pixel_format,
469 				    intel_dsi->lane_count);
470 
471 	/*
472 	 * From clock diagram, to get PLL ratio divider, divide double of DSI
473 	 * link rate (i.e., 2*8x=16x frequency value) by ref clock. Make sure to
474 	 * round 'up' the result
475 	 */
476 	dsi_ratio = DIV_ROUND_UP(dsi_clk * 2, BXT_REF_CLOCK_KHZ);
477 
478 	if (IS_BROXTON(dev_priv)) {
479 		dsi_ratio_min = BXT_DSI_PLL_RATIO_MIN;
480 		dsi_ratio_max = BXT_DSI_PLL_RATIO_MAX;
481 	} else {
482 		dsi_ratio_min = GLK_DSI_PLL_RATIO_MIN;
483 		dsi_ratio_max = GLK_DSI_PLL_RATIO_MAX;
484 	}
485 
486 	if (dsi_ratio < dsi_ratio_min || dsi_ratio > dsi_ratio_max) {
487 		drm_err(&dev_priv->drm,
488 			"Can't get a suitable ratio from DSI PLL ratios\n");
489 		return -ECHRNG;
490 	} else
491 		drm_dbg_kms(&dev_priv->drm, "DSI PLL calculation is Done!!\n");
492 
493 	/*
494 	 * Program DSI ratio and Select MIPIC and MIPIA PLL output as 8x
495 	 * Spec says both have to be programmed, even if one is not getting
496 	 * used. Configure MIPI_CLOCK_CTL dividers in modeset
497 	 */
498 	config->dsi_pll.ctrl = dsi_ratio | BXT_DSIA_16X_BY2 | BXT_DSIC_16X_BY2;
499 
500 	/* As per recommendation from hardware team,
501 	 * Prog PVD ratio =1 if dsi ratio <= 50
502 	 */
503 	if (IS_BROXTON(dev_priv) && dsi_ratio <= 50)
504 		config->dsi_pll.ctrl |= BXT_DSI_PLL_PVD_RATIO_1;
505 
506 	return 0;
507 }
508 
509 void bxt_dsi_pll_enable(struct intel_encoder *encoder,
510 			const struct intel_crtc_state *config)
511 {
512 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
513 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
514 	enum port port;
515 	u32 val;
516 
517 	drm_dbg_kms(&dev_priv->drm, "\n");
518 
519 	/* Configure PLL vales */
520 	intel_de_write(dev_priv, BXT_DSI_PLL_CTL, config->dsi_pll.ctrl);
521 	intel_de_posting_read(dev_priv, BXT_DSI_PLL_CTL);
522 
523 	/* Program TX, RX, Dphy clocks */
524 	if (IS_BROXTON(dev_priv)) {
525 		for_each_dsi_port(port, intel_dsi->ports)
526 			bxt_dsi_program_clocks(encoder->base.dev, port, config);
527 	} else {
528 		glk_dsi_program_esc_clock(encoder->base.dev, config);
529 	}
530 
531 	/* Enable DSI PLL */
532 	val = intel_de_read(dev_priv, BXT_DSI_PLL_ENABLE);
533 	val |= BXT_DSI_PLL_DO_ENABLE;
534 	intel_de_write(dev_priv, BXT_DSI_PLL_ENABLE, val);
535 
536 	/* Timeout and fail if PLL not locked */
537 	if (intel_de_wait_for_set(dev_priv, BXT_DSI_PLL_ENABLE,
538 				  BXT_DSI_PLL_LOCKED, 1)) {
539 		drm_err(&dev_priv->drm,
540 			"Timed out waiting for DSI PLL to lock\n");
541 		return;
542 	}
543 
544 	drm_dbg_kms(&dev_priv->drm, "DSI PLL locked\n");
545 }
546 
547 void bxt_dsi_reset_clocks(struct intel_encoder *encoder, enum port port)
548 {
549 	u32 tmp;
550 	struct drm_device *dev = encoder->base.dev;
551 	struct drm_i915_private *dev_priv = to_i915(dev);
552 
553 	/* Clear old configurations */
554 	if (IS_BROXTON(dev_priv)) {
555 		tmp = intel_de_read(dev_priv, BXT_MIPI_CLOCK_CTL);
556 		tmp &= ~(BXT_MIPI_TX_ESCLK_FIXDIV_MASK(port));
557 		tmp &= ~(BXT_MIPI_RX_ESCLK_UPPER_FIXDIV_MASK(port));
558 		tmp &= ~(BXT_MIPI_8X_BY3_DIVIDER_MASK(port));
559 		tmp &= ~(BXT_MIPI_RX_ESCLK_LOWER_FIXDIV_MASK(port));
560 		intel_de_write(dev_priv, BXT_MIPI_CLOCK_CTL, tmp);
561 	} else {
562 		tmp = intel_de_read(dev_priv, MIPIO_TXESC_CLK_DIV1);
563 		tmp &= ~GLK_TX_ESC_CLK_DIV1_MASK;
564 		intel_de_write(dev_priv, MIPIO_TXESC_CLK_DIV1, tmp);
565 
566 		tmp = intel_de_read(dev_priv, MIPIO_TXESC_CLK_DIV2);
567 		tmp &= ~GLK_TX_ESC_CLK_DIV2_MASK;
568 		intel_de_write(dev_priv, MIPIO_TXESC_CLK_DIV2, tmp);
569 	}
570 	intel_de_write(dev_priv, MIPI_EOT_DISABLE(port), CLOCKSTOP);
571 }
572 
573 static void assert_dsi_pll(struct drm_i915_private *i915, bool state)
574 {
575 	bool cur_state;
576 
577 	vlv_cck_get(i915);
578 	cur_state = vlv_cck_read(i915, CCK_REG_DSI_PLL_CONTROL) & DSI_PLL_VCO_EN;
579 	vlv_cck_put(i915);
580 
581 	I915_STATE_WARN(cur_state != state,
582 			"DSI PLL state assertion failure (expected %s, current %s)\n",
583 			onoff(state), onoff(cur_state));
584 }
585 
586 void assert_dsi_pll_enabled(struct drm_i915_private *i915)
587 {
588 	assert_dsi_pll(i915, true);
589 }
590 
591 void assert_dsi_pll_disabled(struct drm_i915_private *i915)
592 {
593 	assert_dsi_pll(i915, false);
594 }
595