xref: /openbmc/linux/drivers/clk/ingenic/cgu.c (revision 6d99a79c)
1 /*
2  * Ingenic SoC CGU driver
3  *
4  * Copyright (c) 2013-2015 Imagination Technologies
5  * Author: Paul Burton <paul.burton@mips.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation; either version 2 of
10  * the License, or (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  */
17 
18 #include <linux/bitops.h>
19 #include <linux/clk.h>
20 #include <linux/clk-provider.h>
21 #include <linux/clkdev.h>
22 #include <linux/delay.h>
23 #include <linux/math64.h>
24 #include <linux/of.h>
25 #include <linux/of_address.h>
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
28 #include "cgu.h"
29 
30 #define MHZ (1000 * 1000)
31 
32 /**
33  * ingenic_cgu_gate_get() - get the value of clock gate register bit
34  * @cgu: reference to the CGU whose registers should be read
35  * @info: info struct describing the gate bit
36  *
37  * Retrieves the state of the clock gate bit described by info. The
38  * caller must hold cgu->lock.
39  *
40  * Return: true if the gate bit is set, else false.
41  */
42 static inline bool
43 ingenic_cgu_gate_get(struct ingenic_cgu *cgu,
44 		     const struct ingenic_cgu_gate_info *info)
45 {
46 	return !!(readl(cgu->base + info->reg) & BIT(info->bit))
47 		^ info->clear_to_gate;
48 }
49 
50 /**
51  * ingenic_cgu_gate_set() - set the value of clock gate register bit
52  * @cgu: reference to the CGU whose registers should be modified
53  * @info: info struct describing the gate bit
54  * @val: non-zero to gate a clock, otherwise zero
55  *
56  * Sets the given gate bit in order to gate or ungate a clock.
57  *
58  * The caller must hold cgu->lock.
59  */
60 static inline void
61 ingenic_cgu_gate_set(struct ingenic_cgu *cgu,
62 		     const struct ingenic_cgu_gate_info *info, bool val)
63 {
64 	u32 clkgr = readl(cgu->base + info->reg);
65 
66 	if (val ^ info->clear_to_gate)
67 		clkgr |= BIT(info->bit);
68 	else
69 		clkgr &= ~BIT(info->bit);
70 
71 	writel(clkgr, cgu->base + info->reg);
72 }
73 
74 /*
75  * PLL operations
76  */
77 
78 static unsigned long
79 ingenic_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
80 {
81 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
82 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
83 	const struct ingenic_cgu_clk_info *clk_info;
84 	const struct ingenic_cgu_pll_info *pll_info;
85 	unsigned m, n, od_enc, od;
86 	bool bypass, enable;
87 	unsigned long flags;
88 	u32 ctl;
89 
90 	clk_info = &cgu->clock_info[ingenic_clk->idx];
91 	BUG_ON(clk_info->type != CGU_CLK_PLL);
92 	pll_info = &clk_info->pll;
93 
94 	spin_lock_irqsave(&cgu->lock, flags);
95 	ctl = readl(cgu->base + pll_info->reg);
96 	spin_unlock_irqrestore(&cgu->lock, flags);
97 
98 	m = (ctl >> pll_info->m_shift) & GENMASK(pll_info->m_bits - 1, 0);
99 	m += pll_info->m_offset;
100 	n = (ctl >> pll_info->n_shift) & GENMASK(pll_info->n_bits - 1, 0);
101 	n += pll_info->n_offset;
102 	od_enc = ctl >> pll_info->od_shift;
103 	od_enc &= GENMASK(pll_info->od_bits - 1, 0);
104 	bypass = !pll_info->no_bypass_bit &&
105 		 !!(ctl & BIT(pll_info->bypass_bit));
106 	enable = !!(ctl & BIT(pll_info->enable_bit));
107 
108 	if (bypass)
109 		return parent_rate;
110 
111 	for (od = 0; od < pll_info->od_max; od++) {
112 		if (pll_info->od_encoding[od] == od_enc)
113 			break;
114 	}
115 	BUG_ON(od == pll_info->od_max);
116 	od++;
117 
118 	return div_u64((u64)parent_rate * m, n * od);
119 }
120 
121 static unsigned long
122 ingenic_pll_calc(const struct ingenic_cgu_clk_info *clk_info,
123 		 unsigned long rate, unsigned long parent_rate,
124 		 unsigned *pm, unsigned *pn, unsigned *pod)
125 {
126 	const struct ingenic_cgu_pll_info *pll_info;
127 	unsigned m, n, od;
128 
129 	pll_info = &clk_info->pll;
130 	od = 1;
131 
132 	/*
133 	 * The frequency after the input divider must be between 10 and 50 MHz.
134 	 * The highest divider yields the best resolution.
135 	 */
136 	n = parent_rate / (10 * MHZ);
137 	n = min_t(unsigned, n, 1 << clk_info->pll.n_bits);
138 	n = max_t(unsigned, n, pll_info->n_offset);
139 
140 	m = (rate / MHZ) * od * n / (parent_rate / MHZ);
141 	m = min_t(unsigned, m, 1 << clk_info->pll.m_bits);
142 	m = max_t(unsigned, m, pll_info->m_offset);
143 
144 	if (pm)
145 		*pm = m;
146 	if (pn)
147 		*pn = n;
148 	if (pod)
149 		*pod = od;
150 
151 	return div_u64((u64)parent_rate * m, n * od);
152 }
153 
154 static inline const struct ingenic_cgu_clk_info *to_clk_info(
155 		struct ingenic_clk *ingenic_clk)
156 {
157 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
158 	const struct ingenic_cgu_clk_info *clk_info;
159 
160 	clk_info = &cgu->clock_info[ingenic_clk->idx];
161 	BUG_ON(clk_info->type != CGU_CLK_PLL);
162 
163 	return clk_info;
164 }
165 
166 static long
167 ingenic_pll_round_rate(struct clk_hw *hw, unsigned long req_rate,
168 		       unsigned long *prate)
169 {
170 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
171 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
172 
173 	return ingenic_pll_calc(clk_info, req_rate, *prate, NULL, NULL, NULL);
174 }
175 
176 static int
177 ingenic_pll_set_rate(struct clk_hw *hw, unsigned long req_rate,
178 		     unsigned long parent_rate)
179 {
180 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
181 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
182 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
183 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
184 	unsigned long rate, flags;
185 	unsigned int m, n, od;
186 	u32 ctl;
187 
188 	rate = ingenic_pll_calc(clk_info, req_rate, parent_rate,
189 			       &m, &n, &od);
190 	if (rate != req_rate)
191 		pr_info("ingenic-cgu: request '%s' rate %luHz, actual %luHz\n",
192 			clk_info->name, req_rate, rate);
193 
194 	spin_lock_irqsave(&cgu->lock, flags);
195 	ctl = readl(cgu->base + pll_info->reg);
196 
197 	ctl &= ~(GENMASK(pll_info->m_bits - 1, 0) << pll_info->m_shift);
198 	ctl |= (m - pll_info->m_offset) << pll_info->m_shift;
199 
200 	ctl &= ~(GENMASK(pll_info->n_bits - 1, 0) << pll_info->n_shift);
201 	ctl |= (n - pll_info->n_offset) << pll_info->n_shift;
202 
203 	ctl &= ~(GENMASK(pll_info->od_bits - 1, 0) << pll_info->od_shift);
204 	ctl |= pll_info->od_encoding[od - 1] << pll_info->od_shift;
205 
206 	writel(ctl, cgu->base + pll_info->reg);
207 	spin_unlock_irqrestore(&cgu->lock, flags);
208 
209 	return 0;
210 }
211 
212 static int ingenic_pll_enable(struct clk_hw *hw)
213 {
214 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
215 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
216 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
217 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
218 	const unsigned int timeout = 100;
219 	unsigned long flags;
220 	unsigned int i;
221 	u32 ctl;
222 
223 	spin_lock_irqsave(&cgu->lock, flags);
224 	ctl = readl(cgu->base + pll_info->reg);
225 
226 	ctl &= ~BIT(pll_info->bypass_bit);
227 	ctl |= BIT(pll_info->enable_bit);
228 
229 	writel(ctl, cgu->base + pll_info->reg);
230 
231 	/* wait for the PLL to stabilise */
232 	for (i = 0; i < timeout; i++) {
233 		ctl = readl(cgu->base + pll_info->reg);
234 		if (ctl & BIT(pll_info->stable_bit))
235 			break;
236 		mdelay(1);
237 	}
238 
239 	spin_unlock_irqrestore(&cgu->lock, flags);
240 
241 	if (i == timeout)
242 		return -EBUSY;
243 
244 	return 0;
245 }
246 
247 static void ingenic_pll_disable(struct clk_hw *hw)
248 {
249 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
250 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
251 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
252 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
253 	unsigned long flags;
254 	u32 ctl;
255 
256 	spin_lock_irqsave(&cgu->lock, flags);
257 	ctl = readl(cgu->base + pll_info->reg);
258 
259 	ctl &= ~BIT(pll_info->enable_bit);
260 
261 	writel(ctl, cgu->base + pll_info->reg);
262 	spin_unlock_irqrestore(&cgu->lock, flags);
263 }
264 
265 static int ingenic_pll_is_enabled(struct clk_hw *hw)
266 {
267 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
268 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
269 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
270 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
271 	unsigned long flags;
272 	u32 ctl;
273 
274 	spin_lock_irqsave(&cgu->lock, flags);
275 	ctl = readl(cgu->base + pll_info->reg);
276 	spin_unlock_irqrestore(&cgu->lock, flags);
277 
278 	return !!(ctl & BIT(pll_info->enable_bit));
279 }
280 
281 static const struct clk_ops ingenic_pll_ops = {
282 	.recalc_rate = ingenic_pll_recalc_rate,
283 	.round_rate = ingenic_pll_round_rate,
284 	.set_rate = ingenic_pll_set_rate,
285 
286 	.enable = ingenic_pll_enable,
287 	.disable = ingenic_pll_disable,
288 	.is_enabled = ingenic_pll_is_enabled,
289 };
290 
291 /*
292  * Operations for all non-PLL clocks
293  */
294 
295 static u8 ingenic_clk_get_parent(struct clk_hw *hw)
296 {
297 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
298 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
299 	const struct ingenic_cgu_clk_info *clk_info;
300 	u32 reg;
301 	u8 i, hw_idx, idx = 0;
302 
303 	clk_info = &cgu->clock_info[ingenic_clk->idx];
304 
305 	if (clk_info->type & CGU_CLK_MUX) {
306 		reg = readl(cgu->base + clk_info->mux.reg);
307 		hw_idx = (reg >> clk_info->mux.shift) &
308 			 GENMASK(clk_info->mux.bits - 1, 0);
309 
310 		/*
311 		 * Convert the hardware index to the parent index by skipping
312 		 * over any -1's in the parents array.
313 		 */
314 		for (i = 0; i < hw_idx; i++) {
315 			if (clk_info->parents[i] != -1)
316 				idx++;
317 		}
318 	}
319 
320 	return idx;
321 }
322 
323 static int ingenic_clk_set_parent(struct clk_hw *hw, u8 idx)
324 {
325 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
326 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
327 	const struct ingenic_cgu_clk_info *clk_info;
328 	unsigned long flags;
329 	u8 curr_idx, hw_idx, num_poss;
330 	u32 reg, mask;
331 
332 	clk_info = &cgu->clock_info[ingenic_clk->idx];
333 
334 	if (clk_info->type & CGU_CLK_MUX) {
335 		/*
336 		 * Convert the parent index to the hardware index by adding
337 		 * 1 for any -1 in the parents array preceding the given
338 		 * index. That is, we want the index of idx'th entry in
339 		 * clk_info->parents which does not equal -1.
340 		 */
341 		hw_idx = curr_idx = 0;
342 		num_poss = 1 << clk_info->mux.bits;
343 		for (; hw_idx < num_poss; hw_idx++) {
344 			if (clk_info->parents[hw_idx] == -1)
345 				continue;
346 			if (curr_idx == idx)
347 				break;
348 			curr_idx++;
349 		}
350 
351 		/* idx should always be a valid parent */
352 		BUG_ON(curr_idx != idx);
353 
354 		mask = GENMASK(clk_info->mux.bits - 1, 0);
355 		mask <<= clk_info->mux.shift;
356 
357 		spin_lock_irqsave(&cgu->lock, flags);
358 
359 		/* write the register */
360 		reg = readl(cgu->base + clk_info->mux.reg);
361 		reg &= ~mask;
362 		reg |= hw_idx << clk_info->mux.shift;
363 		writel(reg, cgu->base + clk_info->mux.reg);
364 
365 		spin_unlock_irqrestore(&cgu->lock, flags);
366 		return 0;
367 	}
368 
369 	return idx ? -EINVAL : 0;
370 }
371 
372 static unsigned long
373 ingenic_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
374 {
375 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
376 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
377 	const struct ingenic_cgu_clk_info *clk_info;
378 	unsigned long rate = parent_rate;
379 	u32 div_reg, div;
380 
381 	clk_info = &cgu->clock_info[ingenic_clk->idx];
382 
383 	if (clk_info->type & CGU_CLK_DIV) {
384 		div_reg = readl(cgu->base + clk_info->div.reg);
385 		div = (div_reg >> clk_info->div.shift) &
386 		      GENMASK(clk_info->div.bits - 1, 0);
387 		div += 1;
388 		div *= clk_info->div.div;
389 
390 		rate /= div;
391 	} else if (clk_info->type & CGU_CLK_FIXDIV) {
392 		rate /= clk_info->fixdiv.div;
393 	}
394 
395 	return rate;
396 }
397 
398 static unsigned
399 ingenic_clk_calc_div(const struct ingenic_cgu_clk_info *clk_info,
400 		     unsigned long parent_rate, unsigned long req_rate)
401 {
402 	unsigned div;
403 
404 	/* calculate the divide */
405 	div = DIV_ROUND_UP(parent_rate, req_rate);
406 
407 	/* and impose hardware constraints */
408 	div = min_t(unsigned, div, 1 << clk_info->div.bits);
409 	div = max_t(unsigned, div, 1);
410 
411 	/*
412 	 * If the divider value itself must be divided before being written to
413 	 * the divider register, we must ensure we don't have any bits set that
414 	 * would be lost as a result of doing so.
415 	 */
416 	div /= clk_info->div.div;
417 	div *= clk_info->div.div;
418 
419 	return div;
420 }
421 
422 static long
423 ingenic_clk_round_rate(struct clk_hw *hw, unsigned long req_rate,
424 		       unsigned long *parent_rate)
425 {
426 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
427 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
428 	const struct ingenic_cgu_clk_info *clk_info;
429 	long rate = *parent_rate;
430 
431 	clk_info = &cgu->clock_info[ingenic_clk->idx];
432 
433 	if (clk_info->type & CGU_CLK_DIV)
434 		rate /= ingenic_clk_calc_div(clk_info, *parent_rate, req_rate);
435 	else if (clk_info->type & CGU_CLK_FIXDIV)
436 		rate /= clk_info->fixdiv.div;
437 
438 	return rate;
439 }
440 
441 static int
442 ingenic_clk_set_rate(struct clk_hw *hw, unsigned long req_rate,
443 		     unsigned long parent_rate)
444 {
445 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
446 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
447 	const struct ingenic_cgu_clk_info *clk_info;
448 	const unsigned timeout = 100;
449 	unsigned long rate, flags;
450 	unsigned div, i;
451 	u32 reg, mask;
452 	int ret = 0;
453 
454 	clk_info = &cgu->clock_info[ingenic_clk->idx];
455 
456 	if (clk_info->type & CGU_CLK_DIV) {
457 		div = ingenic_clk_calc_div(clk_info, parent_rate, req_rate);
458 		rate = parent_rate / div;
459 
460 		if (rate != req_rate)
461 			return -EINVAL;
462 
463 		spin_lock_irqsave(&cgu->lock, flags);
464 		reg = readl(cgu->base + clk_info->div.reg);
465 
466 		/* update the divide */
467 		mask = GENMASK(clk_info->div.bits - 1, 0);
468 		reg &= ~(mask << clk_info->div.shift);
469 		reg |= ((div / clk_info->div.div) - 1) << clk_info->div.shift;
470 
471 		/* clear the stop bit */
472 		if (clk_info->div.stop_bit != -1)
473 			reg &= ~BIT(clk_info->div.stop_bit);
474 
475 		/* set the change enable bit */
476 		if (clk_info->div.ce_bit != -1)
477 			reg |= BIT(clk_info->div.ce_bit);
478 
479 		/* update the hardware */
480 		writel(reg, cgu->base + clk_info->div.reg);
481 
482 		/* wait for the change to take effect */
483 		if (clk_info->div.busy_bit != -1) {
484 			for (i = 0; i < timeout; i++) {
485 				reg = readl(cgu->base + clk_info->div.reg);
486 				if (!(reg & BIT(clk_info->div.busy_bit)))
487 					break;
488 				mdelay(1);
489 			}
490 			if (i == timeout)
491 				ret = -EBUSY;
492 		}
493 
494 		spin_unlock_irqrestore(&cgu->lock, flags);
495 		return ret;
496 	}
497 
498 	return -EINVAL;
499 }
500 
501 static int ingenic_clk_enable(struct clk_hw *hw)
502 {
503 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
504 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
505 	const struct ingenic_cgu_clk_info *clk_info;
506 	unsigned long flags;
507 
508 	clk_info = &cgu->clock_info[ingenic_clk->idx];
509 
510 	if (clk_info->type & CGU_CLK_GATE) {
511 		/* ungate the clock */
512 		spin_lock_irqsave(&cgu->lock, flags);
513 		ingenic_cgu_gate_set(cgu, &clk_info->gate, false);
514 		spin_unlock_irqrestore(&cgu->lock, flags);
515 
516 		if (clk_info->gate.delay_us)
517 			udelay(clk_info->gate.delay_us);
518 	}
519 
520 	return 0;
521 }
522 
523 static void ingenic_clk_disable(struct clk_hw *hw)
524 {
525 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
526 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
527 	const struct ingenic_cgu_clk_info *clk_info;
528 	unsigned long flags;
529 
530 	clk_info = &cgu->clock_info[ingenic_clk->idx];
531 
532 	if (clk_info->type & CGU_CLK_GATE) {
533 		/* gate the clock */
534 		spin_lock_irqsave(&cgu->lock, flags);
535 		ingenic_cgu_gate_set(cgu, &clk_info->gate, true);
536 		spin_unlock_irqrestore(&cgu->lock, flags);
537 	}
538 }
539 
540 static int ingenic_clk_is_enabled(struct clk_hw *hw)
541 {
542 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
543 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
544 	const struct ingenic_cgu_clk_info *clk_info;
545 	unsigned long flags;
546 	int enabled = 1;
547 
548 	clk_info = &cgu->clock_info[ingenic_clk->idx];
549 
550 	if (clk_info->type & CGU_CLK_GATE) {
551 		spin_lock_irqsave(&cgu->lock, flags);
552 		enabled = !ingenic_cgu_gate_get(cgu, &clk_info->gate);
553 		spin_unlock_irqrestore(&cgu->lock, flags);
554 	}
555 
556 	return enabled;
557 }
558 
559 static const struct clk_ops ingenic_clk_ops = {
560 	.get_parent = ingenic_clk_get_parent,
561 	.set_parent = ingenic_clk_set_parent,
562 
563 	.recalc_rate = ingenic_clk_recalc_rate,
564 	.round_rate = ingenic_clk_round_rate,
565 	.set_rate = ingenic_clk_set_rate,
566 
567 	.enable = ingenic_clk_enable,
568 	.disable = ingenic_clk_disable,
569 	.is_enabled = ingenic_clk_is_enabled,
570 };
571 
572 /*
573  * Setup functions.
574  */
575 
576 static int ingenic_register_clock(struct ingenic_cgu *cgu, unsigned idx)
577 {
578 	const struct ingenic_cgu_clk_info *clk_info = &cgu->clock_info[idx];
579 	struct clk_init_data clk_init;
580 	struct ingenic_clk *ingenic_clk = NULL;
581 	struct clk *clk, *parent;
582 	const char *parent_names[4];
583 	unsigned caps, i, num_possible;
584 	int err = -EINVAL;
585 
586 	BUILD_BUG_ON(ARRAY_SIZE(clk_info->parents) > ARRAY_SIZE(parent_names));
587 
588 	if (clk_info->type == CGU_CLK_EXT) {
589 		clk = of_clk_get_by_name(cgu->np, clk_info->name);
590 		if (IS_ERR(clk)) {
591 			pr_err("%s: no external clock '%s' provided\n",
592 			       __func__, clk_info->name);
593 			err = -ENODEV;
594 			goto out;
595 		}
596 		err = clk_register_clkdev(clk, clk_info->name, NULL);
597 		if (err) {
598 			clk_put(clk);
599 			goto out;
600 		}
601 		cgu->clocks.clks[idx] = clk;
602 		return 0;
603 	}
604 
605 	if (!clk_info->type) {
606 		pr_err("%s: no clock type specified for '%s'\n", __func__,
607 		       clk_info->name);
608 		goto out;
609 	}
610 
611 	ingenic_clk = kzalloc(sizeof(*ingenic_clk), GFP_KERNEL);
612 	if (!ingenic_clk) {
613 		err = -ENOMEM;
614 		goto out;
615 	}
616 
617 	ingenic_clk->hw.init = &clk_init;
618 	ingenic_clk->cgu = cgu;
619 	ingenic_clk->idx = idx;
620 
621 	clk_init.name = clk_info->name;
622 	clk_init.flags = 0;
623 	clk_init.parent_names = parent_names;
624 
625 	caps = clk_info->type;
626 
627 	if (caps & (CGU_CLK_MUX | CGU_CLK_CUSTOM)) {
628 		clk_init.num_parents = 0;
629 
630 		if (caps & CGU_CLK_MUX)
631 			num_possible = 1 << clk_info->mux.bits;
632 		else
633 			num_possible = ARRAY_SIZE(clk_info->parents);
634 
635 		for (i = 0; i < num_possible; i++) {
636 			if (clk_info->parents[i] == -1)
637 				continue;
638 
639 			parent = cgu->clocks.clks[clk_info->parents[i]];
640 			parent_names[clk_init.num_parents] =
641 				__clk_get_name(parent);
642 			clk_init.num_parents++;
643 		}
644 
645 		BUG_ON(!clk_init.num_parents);
646 		BUG_ON(clk_init.num_parents > ARRAY_SIZE(parent_names));
647 	} else {
648 		BUG_ON(clk_info->parents[0] == -1);
649 		clk_init.num_parents = 1;
650 		parent = cgu->clocks.clks[clk_info->parents[0]];
651 		parent_names[0] = __clk_get_name(parent);
652 	}
653 
654 	if (caps & CGU_CLK_CUSTOM) {
655 		clk_init.ops = clk_info->custom.clk_ops;
656 
657 		caps &= ~CGU_CLK_CUSTOM;
658 
659 		if (caps) {
660 			pr_err("%s: custom clock may not be combined with type 0x%x\n",
661 			       __func__, caps);
662 			goto out;
663 		}
664 	} else if (caps & CGU_CLK_PLL) {
665 		clk_init.ops = &ingenic_pll_ops;
666 		clk_init.flags |= CLK_SET_RATE_GATE;
667 
668 		caps &= ~CGU_CLK_PLL;
669 
670 		if (caps) {
671 			pr_err("%s: PLL may not be combined with type 0x%x\n",
672 			       __func__, caps);
673 			goto out;
674 		}
675 	} else {
676 		clk_init.ops = &ingenic_clk_ops;
677 	}
678 
679 	/* nothing to do for gates or fixed dividers */
680 	caps &= ~(CGU_CLK_GATE | CGU_CLK_FIXDIV);
681 
682 	if (caps & CGU_CLK_MUX) {
683 		if (!(caps & CGU_CLK_MUX_GLITCHFREE))
684 			clk_init.flags |= CLK_SET_PARENT_GATE;
685 
686 		caps &= ~(CGU_CLK_MUX | CGU_CLK_MUX_GLITCHFREE);
687 	}
688 
689 	if (caps & CGU_CLK_DIV) {
690 		caps &= ~CGU_CLK_DIV;
691 	} else {
692 		/* pass rate changes to the parent clock */
693 		clk_init.flags |= CLK_SET_RATE_PARENT;
694 	}
695 
696 	if (caps) {
697 		pr_err("%s: unknown clock type 0x%x\n", __func__, caps);
698 		goto out;
699 	}
700 
701 	clk = clk_register(NULL, &ingenic_clk->hw);
702 	if (IS_ERR(clk)) {
703 		pr_err("%s: failed to register clock '%s'\n", __func__,
704 		       clk_info->name);
705 		err = PTR_ERR(clk);
706 		goto out;
707 	}
708 
709 	err = clk_register_clkdev(clk, clk_info->name, NULL);
710 	if (err)
711 		goto out;
712 
713 	cgu->clocks.clks[idx] = clk;
714 out:
715 	if (err)
716 		kfree(ingenic_clk);
717 	return err;
718 }
719 
720 struct ingenic_cgu *
721 ingenic_cgu_new(const struct ingenic_cgu_clk_info *clock_info,
722 		unsigned num_clocks, struct device_node *np)
723 {
724 	struct ingenic_cgu *cgu;
725 
726 	cgu = kzalloc(sizeof(*cgu), GFP_KERNEL);
727 	if (!cgu)
728 		goto err_out;
729 
730 	cgu->base = of_iomap(np, 0);
731 	if (!cgu->base) {
732 		pr_err("%s: failed to map CGU registers\n", __func__);
733 		goto err_out_free;
734 	}
735 
736 	cgu->np = np;
737 	cgu->clock_info = clock_info;
738 	cgu->clocks.clk_num = num_clocks;
739 
740 	spin_lock_init(&cgu->lock);
741 
742 	return cgu;
743 
744 err_out_free:
745 	kfree(cgu);
746 err_out:
747 	return NULL;
748 }
749 
750 int ingenic_cgu_register_clocks(struct ingenic_cgu *cgu)
751 {
752 	unsigned i;
753 	int err;
754 
755 	cgu->clocks.clks = kcalloc(cgu->clocks.clk_num, sizeof(struct clk *),
756 				   GFP_KERNEL);
757 	if (!cgu->clocks.clks) {
758 		err = -ENOMEM;
759 		goto err_out;
760 	}
761 
762 	for (i = 0; i < cgu->clocks.clk_num; i++) {
763 		err = ingenic_register_clock(cgu, i);
764 		if (err)
765 			goto err_out_unregister;
766 	}
767 
768 	err = of_clk_add_provider(cgu->np, of_clk_src_onecell_get,
769 				  &cgu->clocks);
770 	if (err)
771 		goto err_out_unregister;
772 
773 	return 0;
774 
775 err_out_unregister:
776 	for (i = 0; i < cgu->clocks.clk_num; i++) {
777 		if (!cgu->clocks.clks[i])
778 			continue;
779 		if (cgu->clock_info[i].type & CGU_CLK_EXT)
780 			clk_put(cgu->clocks.clks[i]);
781 		else
782 			clk_unregister(cgu->clocks.clks[i]);
783 	}
784 	kfree(cgu->clocks.clks);
785 err_out:
786 	return err;
787 }
788