xref: /linux/drivers/clk/ti/dpll3xxx.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
1 /*
2  * OMAP3/4 - specific DPLL control functions
3  *
4  * Copyright (C) 2009-2010 Texas Instruments, Inc.
5  * Copyright (C) 2009-2010 Nokia Corporation
6  *
7  * Written by Paul Walmsley
8  * Testing and integration fixes by Jouni Högander
9  *
10  * 36xx support added by Vishwanath BS, Richard Woodruff, and Nishanth
11  * Menon
12  *
13  * Parts of this code are based on code written by
14  * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
15  *
16  * This program is free software; you can redistribute it and/or modify
17  * it under the terms of the GNU General Public License version 2 as
18  * published by the Free Software Foundation.
19  */
20 
21 #include <linux/kernel.h>
22 #include <linux/device.h>
23 #include <linux/list.h>
24 #include <linux/errno.h>
25 #include <linux/delay.h>
26 #include <linux/clk.h>
27 #include <linux/io.h>
28 #include <linux/bitops.h>
29 #include <linux/clkdev.h>
30 #include <linux/clk/ti.h>
31 
32 #include "clock.h"
33 
34 /* CM_AUTOIDLE_PLL*.AUTO_* bit values */
35 #define DPLL_AUTOIDLE_DISABLE			0x0
36 #define DPLL_AUTOIDLE_LOW_POWER_STOP		0x1
37 
38 #define MAX_DPLL_WAIT_TRIES		1000000
39 
40 #define OMAP3XXX_EN_DPLL_LOCKED		0x7
41 
42 /* Forward declarations */
43 static u32 omap3_dpll_autoidle_read(struct clk_hw_omap *clk);
44 static void omap3_dpll_deny_idle(struct clk_hw_omap *clk);
45 static void omap3_dpll_allow_idle(struct clk_hw_omap *clk);
46 
47 /* Private functions */
48 
49 /* _omap3_dpll_write_clken - write clken_bits arg to a DPLL's enable bits */
50 static void _omap3_dpll_write_clken(struct clk_hw_omap *clk, u8 clken_bits)
51 {
52 	const struct dpll_data *dd;
53 	u32 v;
54 
55 	dd = clk->dpll_data;
56 
57 	v = ti_clk_ll_ops->clk_readl(dd->control_reg);
58 	v &= ~dd->enable_mask;
59 	v |= clken_bits << __ffs(dd->enable_mask);
60 	ti_clk_ll_ops->clk_writel(v, dd->control_reg);
61 }
62 
63 /* _omap3_wait_dpll_status: wait for a DPLL to enter a specific state */
64 static int _omap3_wait_dpll_status(struct clk_hw_omap *clk, u8 state)
65 {
66 	const struct dpll_data *dd;
67 	int i = 0;
68 	int ret = -EINVAL;
69 	const char *clk_name;
70 
71 	dd = clk->dpll_data;
72 	clk_name = clk_hw_get_name(&clk->hw);
73 
74 	state <<= __ffs(dd->idlest_mask);
75 
76 	while (((ti_clk_ll_ops->clk_readl(dd->idlest_reg) & dd->idlest_mask)
77 		!= state) && i < MAX_DPLL_WAIT_TRIES) {
78 		i++;
79 		udelay(1);
80 	}
81 
82 	if (i == MAX_DPLL_WAIT_TRIES) {
83 		pr_err("clock: %s failed transition to '%s'\n",
84 		       clk_name, (state) ? "locked" : "bypassed");
85 	} else {
86 		pr_debug("clock: %s transition to '%s' in %d loops\n",
87 			 clk_name, (state) ? "locked" : "bypassed", i);
88 
89 		ret = 0;
90 	}
91 
92 	return ret;
93 }
94 
95 /* From 3430 TRM ES2 4.7.6.2 */
96 static u16 _omap3_dpll_compute_freqsel(struct clk_hw_omap *clk, u8 n)
97 {
98 	unsigned long fint;
99 	u16 f = 0;
100 
101 	fint = clk_get_rate(clk->dpll_data->clk_ref) / n;
102 
103 	pr_debug("clock: fint is %lu\n", fint);
104 
105 	if (fint >= 750000 && fint <= 1000000)
106 		f = 0x3;
107 	else if (fint > 1000000 && fint <= 1250000)
108 		f = 0x4;
109 	else if (fint > 1250000 && fint <= 1500000)
110 		f = 0x5;
111 	else if (fint > 1500000 && fint <= 1750000)
112 		f = 0x6;
113 	else if (fint > 1750000 && fint <= 2100000)
114 		f = 0x7;
115 	else if (fint > 7500000 && fint <= 10000000)
116 		f = 0xB;
117 	else if (fint > 10000000 && fint <= 12500000)
118 		f = 0xC;
119 	else if (fint > 12500000 && fint <= 15000000)
120 		f = 0xD;
121 	else if (fint > 15000000 && fint <= 17500000)
122 		f = 0xE;
123 	else if (fint > 17500000 && fint <= 21000000)
124 		f = 0xF;
125 	else
126 		pr_debug("clock: unknown freqsel setting for %d\n", n);
127 
128 	return f;
129 }
130 
131 /*
132  * _omap3_noncore_dpll_lock - instruct a DPLL to lock and wait for readiness
133  * @clk: pointer to a DPLL struct clk
134  *
135  * Instructs a non-CORE DPLL to lock.  Waits for the DPLL to report
136  * readiness before returning.  Will save and restore the DPLL's
137  * autoidle state across the enable, per the CDP code.  If the DPLL
138  * locked successfully, return 0; if the DPLL did not lock in the time
139  * allotted, or DPLL3 was passed in, return -EINVAL.
140  */
141 static int _omap3_noncore_dpll_lock(struct clk_hw_omap *clk)
142 {
143 	const struct dpll_data *dd;
144 	u8 ai;
145 	u8 state = 1;
146 	int r = 0;
147 
148 	pr_debug("clock: locking DPLL %s\n", clk_hw_get_name(&clk->hw));
149 
150 	dd = clk->dpll_data;
151 	state <<= __ffs(dd->idlest_mask);
152 
153 	/* Check if already locked */
154 	if ((ti_clk_ll_ops->clk_readl(dd->idlest_reg) & dd->idlest_mask) ==
155 	    state)
156 		goto done;
157 
158 	ai = omap3_dpll_autoidle_read(clk);
159 
160 	if (ai)
161 		omap3_dpll_deny_idle(clk);
162 
163 	_omap3_dpll_write_clken(clk, DPLL_LOCKED);
164 
165 	r = _omap3_wait_dpll_status(clk, 1);
166 
167 	if (ai)
168 		omap3_dpll_allow_idle(clk);
169 
170 done:
171 	return r;
172 }
173 
174 /*
175  * _omap3_noncore_dpll_bypass - instruct a DPLL to bypass and wait for readiness
176  * @clk: pointer to a DPLL struct clk
177  *
178  * Instructs a non-CORE DPLL to enter low-power bypass mode.  In
179  * bypass mode, the DPLL's rate is set equal to its parent clock's
180  * rate.  Waits for the DPLL to report readiness before returning.
181  * Will save and restore the DPLL's autoidle state across the enable,
182  * per the CDP code.  If the DPLL entered bypass mode successfully,
183  * return 0; if the DPLL did not enter bypass in the time allotted, or
184  * DPLL3 was passed in, or the DPLL does not support low-power bypass,
185  * return -EINVAL.
186  */
187 static int _omap3_noncore_dpll_bypass(struct clk_hw_omap *clk)
188 {
189 	int r;
190 	u8 ai;
191 
192 	if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_BYPASS)))
193 		return -EINVAL;
194 
195 	pr_debug("clock: configuring DPLL %s for low-power bypass\n",
196 		 clk_hw_get_name(&clk->hw));
197 
198 	ai = omap3_dpll_autoidle_read(clk);
199 
200 	_omap3_dpll_write_clken(clk, DPLL_LOW_POWER_BYPASS);
201 
202 	r = _omap3_wait_dpll_status(clk, 0);
203 
204 	if (ai)
205 		omap3_dpll_allow_idle(clk);
206 
207 	return r;
208 }
209 
210 /*
211  * _omap3_noncore_dpll_stop - instruct a DPLL to stop
212  * @clk: pointer to a DPLL struct clk
213  *
214  * Instructs a non-CORE DPLL to enter low-power stop. Will save and
215  * restore the DPLL's autoidle state across the stop, per the CDP
216  * code.  If DPLL3 was passed in, or the DPLL does not support
217  * low-power stop, return -EINVAL; otherwise, return 0.
218  */
219 static int _omap3_noncore_dpll_stop(struct clk_hw_omap *clk)
220 {
221 	u8 ai;
222 
223 	if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_STOP)))
224 		return -EINVAL;
225 
226 	pr_debug("clock: stopping DPLL %s\n", clk_hw_get_name(&clk->hw));
227 
228 	ai = omap3_dpll_autoidle_read(clk);
229 
230 	_omap3_dpll_write_clken(clk, DPLL_LOW_POWER_STOP);
231 
232 	if (ai)
233 		omap3_dpll_allow_idle(clk);
234 
235 	return 0;
236 }
237 
238 /**
239  * _lookup_dco - Lookup DCO used by j-type DPLL
240  * @clk: pointer to a DPLL struct clk
241  * @dco: digital control oscillator selector
242  * @m: DPLL multiplier to set
243  * @n: DPLL divider to set
244  *
245  * See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)"
246  *
247  * XXX This code is not needed for 3430/AM35xx; can it be optimized
248  * out in non-multi-OMAP builds for those chips?
249  */
250 static void _lookup_dco(struct clk_hw_omap *clk, u8 *dco, u16 m, u8 n)
251 {
252 	unsigned long fint, clkinp; /* watch out for overflow */
253 
254 	clkinp = clk_hw_get_rate(clk_hw_get_parent(&clk->hw));
255 	fint = (clkinp / n) * m;
256 
257 	if (fint < 1000000000)
258 		*dco = 2;
259 	else
260 		*dco = 4;
261 }
262 
263 /**
264  * _lookup_sddiv - Calculate sigma delta divider for j-type DPLL
265  * @clk: pointer to a DPLL struct clk
266  * @sd_div: target sigma-delta divider
267  * @m: DPLL multiplier to set
268  * @n: DPLL divider to set
269  *
270  * See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)"
271  *
272  * XXX This code is not needed for 3430/AM35xx; can it be optimized
273  * out in non-multi-OMAP builds for those chips?
274  */
275 static void _lookup_sddiv(struct clk_hw_omap *clk, u8 *sd_div, u16 m, u8 n)
276 {
277 	unsigned long clkinp, sd; /* watch out for overflow */
278 	int mod1, mod2;
279 
280 	clkinp = clk_hw_get_rate(clk_hw_get_parent(&clk->hw));
281 
282 	/*
283 	 * target sigma-delta to near 250MHz
284 	 * sd = ceil[(m/(n+1)) * (clkinp_MHz / 250)]
285 	 */
286 	clkinp /= 100000; /* shift from MHz to 10*Hz for 38.4 and 19.2 */
287 	mod1 = (clkinp * m) % (250 * n);
288 	sd = (clkinp * m) / (250 * n);
289 	mod2 = sd % 10;
290 	sd /= 10;
291 
292 	if (mod1 || mod2)
293 		sd++;
294 	*sd_div = sd;
295 }
296 
297 /*
298  * _omap3_noncore_dpll_program - set non-core DPLL M,N values directly
299  * @clk:	struct clk * of DPLL to set
300  * @freqsel:	FREQSEL value to set
301  *
302  * Program the DPLL with the last M, N values calculated, and wait for
303  * the DPLL to lock. Returns -EINVAL upon error, or 0 upon success.
304  */
305 static int omap3_noncore_dpll_program(struct clk_hw_omap *clk, u16 freqsel)
306 {
307 	struct dpll_data *dd = clk->dpll_data;
308 	u8 dco, sd_div;
309 	u32 v;
310 
311 	/* 3430 ES2 TRM: 4.7.6.9 DPLL Programming Sequence */
312 	_omap3_noncore_dpll_bypass(clk);
313 
314 	/*
315 	 * Set jitter correction. Jitter correction applicable for OMAP343X
316 	 * only since freqsel field is no longer present on other devices.
317 	 */
318 	if (ti_clk_get_features()->flags & TI_CLK_DPLL_HAS_FREQSEL) {
319 		v = ti_clk_ll_ops->clk_readl(dd->control_reg);
320 		v &= ~dd->freqsel_mask;
321 		v |= freqsel << __ffs(dd->freqsel_mask);
322 		ti_clk_ll_ops->clk_writel(v, dd->control_reg);
323 	}
324 
325 	/* Set DPLL multiplier, divider */
326 	v = ti_clk_ll_ops->clk_readl(dd->mult_div1_reg);
327 
328 	/* Handle Duty Cycle Correction */
329 	if (dd->dcc_mask) {
330 		if (dd->last_rounded_rate >= dd->dcc_rate)
331 			v |= dd->dcc_mask; /* Enable DCC */
332 		else
333 			v &= ~dd->dcc_mask; /* Disable DCC */
334 	}
335 
336 	v &= ~(dd->mult_mask | dd->div1_mask);
337 	v |= dd->last_rounded_m << __ffs(dd->mult_mask);
338 	v |= (dd->last_rounded_n - 1) << __ffs(dd->div1_mask);
339 
340 	/* Configure dco and sd_div for dplls that have these fields */
341 	if (dd->dco_mask) {
342 		_lookup_dco(clk, &dco, dd->last_rounded_m, dd->last_rounded_n);
343 		v &= ~(dd->dco_mask);
344 		v |= dco << __ffs(dd->dco_mask);
345 	}
346 	if (dd->sddiv_mask) {
347 		_lookup_sddiv(clk, &sd_div, dd->last_rounded_m,
348 			      dd->last_rounded_n);
349 		v &= ~(dd->sddiv_mask);
350 		v |= sd_div << __ffs(dd->sddiv_mask);
351 	}
352 
353 	ti_clk_ll_ops->clk_writel(v, dd->mult_div1_reg);
354 
355 	/* Set 4X multiplier and low-power mode */
356 	if (dd->m4xen_mask || dd->lpmode_mask) {
357 		v = ti_clk_ll_ops->clk_readl(dd->control_reg);
358 
359 		if (dd->m4xen_mask) {
360 			if (dd->last_rounded_m4xen)
361 				v |= dd->m4xen_mask;
362 			else
363 				v &= ~dd->m4xen_mask;
364 		}
365 
366 		if (dd->lpmode_mask) {
367 			if (dd->last_rounded_lpmode)
368 				v |= dd->lpmode_mask;
369 			else
370 				v &= ~dd->lpmode_mask;
371 		}
372 
373 		ti_clk_ll_ops->clk_writel(v, dd->control_reg);
374 	}
375 
376 	/* We let the clock framework set the other output dividers later */
377 
378 	/* REVISIT: Set ramp-up delay? */
379 
380 	_omap3_noncore_dpll_lock(clk);
381 
382 	return 0;
383 }
384 
385 /* Public functions */
386 
387 /**
388  * omap3_dpll_recalc - recalculate DPLL rate
389  * @clk: DPLL struct clk
390  *
391  * Recalculate and propagate the DPLL rate.
392  */
393 unsigned long omap3_dpll_recalc(struct clk_hw *hw, unsigned long parent_rate)
394 {
395 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
396 
397 	return omap2_get_dpll_rate(clk);
398 }
399 
400 /* Non-CORE DPLL (e.g., DPLLs that do not control SDRC) clock functions */
401 
402 /**
403  * omap3_noncore_dpll_enable - instruct a DPLL to enter bypass or lock mode
404  * @clk: pointer to a DPLL struct clk
405  *
406  * Instructs a non-CORE DPLL to enable, e.g., to enter bypass or lock.
407  * The choice of modes depends on the DPLL's programmed rate: if it is
408  * the same as the DPLL's parent clock, it will enter bypass;
409  * otherwise, it will enter lock.  This code will wait for the DPLL to
410  * indicate readiness before returning, unless the DPLL takes too long
411  * to enter the target state.  Intended to be used as the struct clk's
412  * enable function.  If DPLL3 was passed in, or the DPLL does not
413  * support low-power stop, or if the DPLL took too long to enter
414  * bypass or lock, return -EINVAL; otherwise, return 0.
415  */
416 int omap3_noncore_dpll_enable(struct clk_hw *hw)
417 {
418 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
419 	int r;
420 	struct dpll_data *dd;
421 	struct clk_hw *parent;
422 
423 	dd = clk->dpll_data;
424 	if (!dd)
425 		return -EINVAL;
426 
427 	if (clk->clkdm) {
428 		r = ti_clk_ll_ops->clkdm_clk_enable(clk->clkdm, hw->clk);
429 		if (r) {
430 			WARN(1,
431 			     "%s: could not enable %s's clockdomain %s: %d\n",
432 			     __func__, clk_hw_get_name(hw),
433 			     clk->clkdm_name, r);
434 			return r;
435 		}
436 	}
437 
438 	parent = clk_hw_get_parent(hw);
439 
440 	if (clk_hw_get_rate(hw) == clk_get_rate(dd->clk_bypass)) {
441 		WARN_ON(parent != __clk_get_hw(dd->clk_bypass));
442 		r = _omap3_noncore_dpll_bypass(clk);
443 	} else {
444 		WARN_ON(parent != __clk_get_hw(dd->clk_ref));
445 		r = _omap3_noncore_dpll_lock(clk);
446 	}
447 
448 	return r;
449 }
450 
451 /**
452  * omap3_noncore_dpll_disable - instruct a DPLL to enter low-power stop
453  * @clk: pointer to a DPLL struct clk
454  *
455  * Instructs a non-CORE DPLL to enter low-power stop.  This function is
456  * intended for use in struct clkops.  No return value.
457  */
458 void omap3_noncore_dpll_disable(struct clk_hw *hw)
459 {
460 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
461 
462 	_omap3_noncore_dpll_stop(clk);
463 	if (clk->clkdm)
464 		ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk);
465 }
466 
467 /* Non-CORE DPLL rate set code */
468 
469 /**
470  * omap3_noncore_dpll_determine_rate - determine rate for a DPLL
471  * @hw: pointer to the clock to determine rate for
472  * @req: target rate request
473  *
474  * Determines which DPLL mode to use for reaching a desired target rate.
475  * Checks whether the DPLL shall be in bypass or locked mode, and if
476  * locked, calculates the M,N values for the DPLL via round-rate.
477  * Returns a 0 on success, negative error value in failure.
478  */
479 int omap3_noncore_dpll_determine_rate(struct clk_hw *hw,
480 				      struct clk_rate_request *req)
481 {
482 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
483 	struct dpll_data *dd;
484 
485 	if (!req->rate)
486 		return -EINVAL;
487 
488 	dd = clk->dpll_data;
489 	if (!dd)
490 		return -EINVAL;
491 
492 	if (clk_get_rate(dd->clk_bypass) == req->rate &&
493 	    (dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) {
494 		req->best_parent_hw = __clk_get_hw(dd->clk_bypass);
495 	} else {
496 		req->rate = omap2_dpll_round_rate(hw, req->rate,
497 					  &req->best_parent_rate);
498 		req->best_parent_hw = __clk_get_hw(dd->clk_ref);
499 	}
500 
501 	req->best_parent_rate = req->rate;
502 
503 	return 0;
504 }
505 
506 /**
507  * omap3_noncore_dpll_set_parent - set parent for a DPLL clock
508  * @hw: pointer to the clock to set parent for
509  * @index: parent index to select
510  *
511  * Sets parent for a DPLL clock. This sets the DPLL into bypass or
512  * locked mode. Returns 0 with success, negative error value otherwise.
513  */
514 int omap3_noncore_dpll_set_parent(struct clk_hw *hw, u8 index)
515 {
516 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
517 	int ret;
518 
519 	if (!hw)
520 		return -EINVAL;
521 
522 	if (index)
523 		ret = _omap3_noncore_dpll_bypass(clk);
524 	else
525 		ret = _omap3_noncore_dpll_lock(clk);
526 
527 	return ret;
528 }
529 
530 /**
531  * omap3_noncore_dpll_set_rate - set rate for a DPLL clock
532  * @hw: pointer to the clock to set parent for
533  * @rate: target rate for the clock
534  * @parent_rate: rate of the parent clock
535  *
536  * Sets rate for a DPLL clock. First checks if the clock parent is
537  * reference clock (in bypass mode, the rate of the clock can't be
538  * changed) and proceeds with the rate change operation. Returns 0
539  * with success, negative error value otherwise.
540  */
541 int omap3_noncore_dpll_set_rate(struct clk_hw *hw, unsigned long rate,
542 				unsigned long parent_rate)
543 {
544 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
545 	struct dpll_data *dd;
546 	u16 freqsel = 0;
547 	int ret;
548 
549 	if (!hw || !rate)
550 		return -EINVAL;
551 
552 	dd = clk->dpll_data;
553 	if (!dd)
554 		return -EINVAL;
555 
556 	if (clk_hw_get_parent(hw) != __clk_get_hw(dd->clk_ref))
557 		return -EINVAL;
558 
559 	if (dd->last_rounded_rate == 0)
560 		return -EINVAL;
561 
562 	/* Freqsel is available only on OMAP343X devices */
563 	if (ti_clk_get_features()->flags & TI_CLK_DPLL_HAS_FREQSEL) {
564 		freqsel = _omap3_dpll_compute_freqsel(clk, dd->last_rounded_n);
565 		WARN_ON(!freqsel);
566 	}
567 
568 	pr_debug("%s: %s: set rate: locking rate to %lu.\n", __func__,
569 		 clk_hw_get_name(hw), rate);
570 
571 	ret = omap3_noncore_dpll_program(clk, freqsel);
572 
573 	return ret;
574 }
575 
576 /**
577  * omap3_noncore_dpll_set_rate_and_parent - set rate and parent for a DPLL clock
578  * @hw: pointer to the clock to set rate and parent for
579  * @rate: target rate for the DPLL
580  * @parent_rate: clock rate of the DPLL parent
581  * @index: new parent index for the DPLL, 0 - reference, 1 - bypass
582  *
583  * Sets rate and parent for a DPLL clock. If new parent is the bypass
584  * clock, only selects the parent. Otherwise proceeds with a rate
585  * change, as this will effectively also change the parent as the
586  * DPLL is put into locked mode. Returns 0 with success, negative error
587  * value otherwise.
588  */
589 int omap3_noncore_dpll_set_rate_and_parent(struct clk_hw *hw,
590 					   unsigned long rate,
591 					   unsigned long parent_rate,
592 					   u8 index)
593 {
594 	int ret;
595 
596 	if (!hw || !rate)
597 		return -EINVAL;
598 
599 	/*
600 	 * clk-ref at index[0], in which case we only need to set rate,
601 	 * the parent will be changed automatically with the lock sequence.
602 	 * With clk-bypass case we only need to change parent.
603 	 */
604 	if (index)
605 		ret = omap3_noncore_dpll_set_parent(hw, index);
606 	else
607 		ret = omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
608 
609 	return ret;
610 }
611 
612 /* DPLL autoidle read/set code */
613 
614 /**
615  * omap3_dpll_autoidle_read - read a DPLL's autoidle bits
616  * @clk: struct clk * of the DPLL to read
617  *
618  * Return the DPLL's autoidle bits, shifted down to bit 0.  Returns
619  * -EINVAL if passed a null pointer or if the struct clk does not
620  * appear to refer to a DPLL.
621  */
622 static u32 omap3_dpll_autoidle_read(struct clk_hw_omap *clk)
623 {
624 	const struct dpll_data *dd;
625 	u32 v;
626 
627 	if (!clk || !clk->dpll_data)
628 		return -EINVAL;
629 
630 	dd = clk->dpll_data;
631 
632 	if (!dd->autoidle_reg)
633 		return -EINVAL;
634 
635 	v = ti_clk_ll_ops->clk_readl(dd->autoidle_reg);
636 	v &= dd->autoidle_mask;
637 	v >>= __ffs(dd->autoidle_mask);
638 
639 	return v;
640 }
641 
642 /**
643  * omap3_dpll_allow_idle - enable DPLL autoidle bits
644  * @clk: struct clk * of the DPLL to operate on
645  *
646  * Enable DPLL automatic idle control.  This automatic idle mode
647  * switching takes effect only when the DPLL is locked, at least on
648  * OMAP3430.  The DPLL will enter low-power stop when its downstream
649  * clocks are gated.  No return value.
650  */
651 static void omap3_dpll_allow_idle(struct clk_hw_omap *clk)
652 {
653 	const struct dpll_data *dd;
654 	u32 v;
655 
656 	if (!clk || !clk->dpll_data)
657 		return;
658 
659 	dd = clk->dpll_data;
660 
661 	if (!dd->autoidle_reg)
662 		return;
663 
664 	/*
665 	 * REVISIT: CORE DPLL can optionally enter low-power bypass
666 	 * by writing 0x5 instead of 0x1.  Add some mechanism to
667 	 * optionally enter this mode.
668 	 */
669 	v = ti_clk_ll_ops->clk_readl(dd->autoidle_reg);
670 	v &= ~dd->autoidle_mask;
671 	v |= DPLL_AUTOIDLE_LOW_POWER_STOP << __ffs(dd->autoidle_mask);
672 	ti_clk_ll_ops->clk_writel(v, dd->autoidle_reg);
673 }
674 
675 /**
676  * omap3_dpll_deny_idle - prevent DPLL from automatically idling
677  * @clk: struct clk * of the DPLL to operate on
678  *
679  * Disable DPLL automatic idle control.  No return value.
680  */
681 static void omap3_dpll_deny_idle(struct clk_hw_omap *clk)
682 {
683 	const struct dpll_data *dd;
684 	u32 v;
685 
686 	if (!clk || !clk->dpll_data)
687 		return;
688 
689 	dd = clk->dpll_data;
690 
691 	if (!dd->autoidle_reg)
692 		return;
693 
694 	v = ti_clk_ll_ops->clk_readl(dd->autoidle_reg);
695 	v &= ~dd->autoidle_mask;
696 	v |= DPLL_AUTOIDLE_DISABLE << __ffs(dd->autoidle_mask);
697 	ti_clk_ll_ops->clk_writel(v, dd->autoidle_reg);
698 }
699 
700 /* Clock control for DPLL outputs */
701 
702 /* Find the parent DPLL for the given clkoutx2 clock */
703 static struct clk_hw_omap *omap3_find_clkoutx2_dpll(struct clk_hw *hw)
704 {
705 	struct clk_hw_omap *pclk = NULL;
706 
707 	/* Walk up the parents of clk, looking for a DPLL */
708 	do {
709 		do {
710 			hw = clk_hw_get_parent(hw);
711 		} while (hw && (clk_hw_get_flags(hw) & CLK_IS_BASIC));
712 		if (!hw)
713 			break;
714 		pclk = to_clk_hw_omap(hw);
715 	} while (pclk && !pclk->dpll_data);
716 
717 	/* clk does not have a DPLL as a parent?  error in the clock data */
718 	if (!pclk) {
719 		WARN_ON(1);
720 		return NULL;
721 	}
722 
723 	return pclk;
724 }
725 
726 /**
727  * omap3_clkoutx2_recalc - recalculate DPLL X2 output virtual clock rate
728  * @clk: DPLL output struct clk
729  *
730  * Using parent clock DPLL data, look up DPLL state.  If locked, set our
731  * rate to the dpll_clk * 2; otherwise, just use dpll_clk.
732  */
733 unsigned long omap3_clkoutx2_recalc(struct clk_hw *hw,
734 				    unsigned long parent_rate)
735 {
736 	const struct dpll_data *dd;
737 	unsigned long rate;
738 	u32 v;
739 	struct clk_hw_omap *pclk = NULL;
740 
741 	if (!parent_rate)
742 		return 0;
743 
744 	pclk = omap3_find_clkoutx2_dpll(hw);
745 
746 	if (!pclk)
747 		return 0;
748 
749 	dd = pclk->dpll_data;
750 
751 	WARN_ON(!dd->enable_mask);
752 
753 	v = ti_clk_ll_ops->clk_readl(dd->control_reg) & dd->enable_mask;
754 	v >>= __ffs(dd->enable_mask);
755 	if ((v != OMAP3XXX_EN_DPLL_LOCKED) || (dd->flags & DPLL_J_TYPE))
756 		rate = parent_rate;
757 	else
758 		rate = parent_rate * 2;
759 	return rate;
760 }
761 
762 /* OMAP3/4 non-CORE DPLL clkops */
763 const struct clk_hw_omap_ops clkhwops_omap3_dpll = {
764 	.allow_idle	= omap3_dpll_allow_idle,
765 	.deny_idle	= omap3_dpll_deny_idle,
766 };
767 
768 /**
769  * omap3_dpll4_set_rate - set rate for omap3 per-dpll
770  * @hw: clock to change
771  * @rate: target rate for clock
772  * @parent_rate: rate of the parent clock
773  *
774  * Check if the current SoC supports the per-dpll reprogram operation
775  * or not, and then do the rate change if supported. Returns -EINVAL
776  * if not supported, 0 for success, and potential error codes from the
777  * clock rate change.
778  */
779 int omap3_dpll4_set_rate(struct clk_hw *hw, unsigned long rate,
780 			 unsigned long parent_rate)
781 {
782 	/*
783 	 * According to the 12-5 CDP code from TI, "Limitation 2.5"
784 	 * on 3430ES1 prevents us from changing DPLL multipliers or dividers
785 	 * on DPLL4.
786 	 */
787 	if (ti_clk_get_features()->flags & TI_CLK_DPLL4_DENY_REPROGRAM) {
788 		pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n");
789 		return -EINVAL;
790 	}
791 
792 	return omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
793 }
794 
795 /**
796  * omap3_dpll4_set_rate_and_parent - set rate and parent for omap3 per-dpll
797  * @hw: clock to change
798  * @rate: target rate for clock
799  * @parent_rate: rate of the parent clock
800  * @index: parent index, 0 - reference clock, 1 - bypass clock
801  *
802  * Check if the current SoC support the per-dpll reprogram operation
803  * or not, and then do the rate + parent change if supported. Returns
804  * -EINVAL if not supported, 0 for success, and potential error codes
805  * from the clock rate change.
806  */
807 int omap3_dpll4_set_rate_and_parent(struct clk_hw *hw, unsigned long rate,
808 				    unsigned long parent_rate, u8 index)
809 {
810 	if (ti_clk_get_features()->flags & TI_CLK_DPLL4_DENY_REPROGRAM) {
811 		pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n");
812 		return -EINVAL;
813 	}
814 
815 	return omap3_noncore_dpll_set_rate_and_parent(hw, rate, parent_rate,
816 						      index);
817 }
818