xref: /openbmc/linux/drivers/clk/ingenic/cgu.c (revision 95298d63)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Ingenic SoC CGU driver
4  *
5  * Copyright (c) 2013-2015 Imagination Technologies
6  * Author: Paul Burton <paul.burton@mips.com>
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/clk.h>
11 #include <linux/clk-provider.h>
12 #include <linux/clkdev.h>
13 #include <linux/delay.h>
14 #include <linux/io.h>
15 #include <linux/math64.h>
16 #include <linux/of.h>
17 #include <linux/of_address.h>
18 #include <linux/slab.h>
19 #include <linux/spinlock.h>
20 #include "cgu.h"
21 
22 #define MHZ (1000 * 1000)
23 
24 /**
25  * ingenic_cgu_gate_get() - get the value of clock gate register bit
26  * @cgu: reference to the CGU whose registers should be read
27  * @info: info struct describing the gate bit
28  *
29  * Retrieves the state of the clock gate bit described by info. The
30  * caller must hold cgu->lock.
31  *
32  * Return: true if the gate bit is set, else false.
33  */
34 static inline bool
35 ingenic_cgu_gate_get(struct ingenic_cgu *cgu,
36 		     const struct ingenic_cgu_gate_info *info)
37 {
38 	return !!(readl(cgu->base + info->reg) & BIT(info->bit))
39 		^ info->clear_to_gate;
40 }
41 
42 /**
43  * ingenic_cgu_gate_set() - set the value of clock gate register bit
44  * @cgu: reference to the CGU whose registers should be modified
45  * @info: info struct describing the gate bit
46  * @val: non-zero to gate a clock, otherwise zero
47  *
48  * Sets the given gate bit in order to gate or ungate a clock.
49  *
50  * The caller must hold cgu->lock.
51  */
52 static inline void
53 ingenic_cgu_gate_set(struct ingenic_cgu *cgu,
54 		     const struct ingenic_cgu_gate_info *info, bool val)
55 {
56 	u32 clkgr = readl(cgu->base + info->reg);
57 
58 	if (val ^ info->clear_to_gate)
59 		clkgr |= BIT(info->bit);
60 	else
61 		clkgr &= ~BIT(info->bit);
62 
63 	writel(clkgr, cgu->base + info->reg);
64 }
65 
66 /*
67  * PLL operations
68  */
69 
70 static unsigned long
71 ingenic_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
72 {
73 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
74 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
75 	const struct ingenic_cgu_clk_info *clk_info;
76 	const struct ingenic_cgu_pll_info *pll_info;
77 	unsigned m, n, od_enc, od;
78 	bool bypass;
79 	u32 ctl;
80 
81 	clk_info = &cgu->clock_info[ingenic_clk->idx];
82 	BUG_ON(clk_info->type != CGU_CLK_PLL);
83 	pll_info = &clk_info->pll;
84 
85 	ctl = readl(cgu->base + pll_info->reg);
86 
87 	m = (ctl >> pll_info->m_shift) & GENMASK(pll_info->m_bits - 1, 0);
88 	m += pll_info->m_offset;
89 	n = (ctl >> pll_info->n_shift) & GENMASK(pll_info->n_bits - 1, 0);
90 	n += pll_info->n_offset;
91 	od_enc = ctl >> pll_info->od_shift;
92 	od_enc &= GENMASK(pll_info->od_bits - 1, 0);
93 
94 	ctl = readl(cgu->base + pll_info->bypass_reg);
95 
96 	bypass = !pll_info->no_bypass_bit &&
97 		 !!(ctl & BIT(pll_info->bypass_bit));
98 
99 	if (bypass)
100 		return parent_rate;
101 
102 	for (od = 0; od < pll_info->od_max; od++) {
103 		if (pll_info->od_encoding[od] == od_enc)
104 			break;
105 	}
106 	BUG_ON(od == pll_info->od_max);
107 	od++;
108 
109 	return div_u64((u64)parent_rate * m * pll_info->rate_multiplier,
110 		n * od);
111 }
112 
113 static unsigned long
114 ingenic_pll_calc(const struct ingenic_cgu_clk_info *clk_info,
115 		 unsigned long rate, unsigned long parent_rate,
116 		 unsigned *pm, unsigned *pn, unsigned *pod)
117 {
118 	const struct ingenic_cgu_pll_info *pll_info;
119 	unsigned m, n, od;
120 
121 	pll_info = &clk_info->pll;
122 	od = 1;
123 
124 	/*
125 	 * The frequency after the input divider must be between 10 and 50 MHz.
126 	 * The highest divider yields the best resolution.
127 	 */
128 	n = parent_rate / (10 * MHZ);
129 	n = min_t(unsigned, n, 1 << clk_info->pll.n_bits);
130 	n = max_t(unsigned, n, pll_info->n_offset);
131 
132 	m = (rate / MHZ) * od * n / (parent_rate / MHZ);
133 	m = min_t(unsigned, m, 1 << clk_info->pll.m_bits);
134 	m = max_t(unsigned, m, pll_info->m_offset);
135 
136 	if (pm)
137 		*pm = m;
138 	if (pn)
139 		*pn = n;
140 	if (pod)
141 		*pod = od;
142 
143 	return div_u64((u64)parent_rate * m * pll_info->rate_multiplier,
144 		n * od);
145 }
146 
147 static inline const struct ingenic_cgu_clk_info *to_clk_info(
148 		struct ingenic_clk *ingenic_clk)
149 {
150 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
151 	const struct ingenic_cgu_clk_info *clk_info;
152 
153 	clk_info = &cgu->clock_info[ingenic_clk->idx];
154 	BUG_ON(clk_info->type != CGU_CLK_PLL);
155 
156 	return clk_info;
157 }
158 
159 static long
160 ingenic_pll_round_rate(struct clk_hw *hw, unsigned long req_rate,
161 		       unsigned long *prate)
162 {
163 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
164 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
165 
166 	return ingenic_pll_calc(clk_info, req_rate, *prate, NULL, NULL, NULL);
167 }
168 
169 static int
170 ingenic_pll_set_rate(struct clk_hw *hw, unsigned long req_rate,
171 		     unsigned long parent_rate)
172 {
173 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
174 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
175 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
176 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
177 	unsigned long rate, flags;
178 	unsigned int m, n, od;
179 	u32 ctl;
180 
181 	rate = ingenic_pll_calc(clk_info, req_rate, parent_rate,
182 			       &m, &n, &od);
183 	if (rate != req_rate)
184 		pr_info("ingenic-cgu: request '%s' rate %luHz, actual %luHz\n",
185 			clk_info->name, req_rate, rate);
186 
187 	spin_lock_irqsave(&cgu->lock, flags);
188 	ctl = readl(cgu->base + pll_info->reg);
189 
190 	ctl &= ~(GENMASK(pll_info->m_bits - 1, 0) << pll_info->m_shift);
191 	ctl |= (m - pll_info->m_offset) << pll_info->m_shift;
192 
193 	ctl &= ~(GENMASK(pll_info->n_bits - 1, 0) << pll_info->n_shift);
194 	ctl |= (n - pll_info->n_offset) << pll_info->n_shift;
195 
196 	ctl &= ~(GENMASK(pll_info->od_bits - 1, 0) << pll_info->od_shift);
197 	ctl |= pll_info->od_encoding[od - 1] << pll_info->od_shift;
198 
199 	writel(ctl, cgu->base + pll_info->reg);
200 	spin_unlock_irqrestore(&cgu->lock, flags);
201 
202 	return 0;
203 }
204 
205 static int ingenic_pll_enable(struct clk_hw *hw)
206 {
207 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
208 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
209 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
210 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
211 	const unsigned int timeout = 100;
212 	unsigned long flags;
213 	unsigned int i;
214 	u32 ctl;
215 
216 	spin_lock_irqsave(&cgu->lock, flags);
217 	ctl = readl(cgu->base + pll_info->bypass_reg);
218 
219 	ctl &= ~BIT(pll_info->bypass_bit);
220 
221 	writel(ctl, cgu->base + pll_info->bypass_reg);
222 
223 	ctl = readl(cgu->base + pll_info->reg);
224 
225 	ctl |= BIT(pll_info->enable_bit);
226 
227 	writel(ctl, cgu->base + pll_info->reg);
228 
229 	/* wait for the PLL to stabilise */
230 	for (i = 0; i < timeout; i++) {
231 		ctl = readl(cgu->base + pll_info->reg);
232 		if (ctl & BIT(pll_info->stable_bit))
233 			break;
234 		mdelay(1);
235 	}
236 
237 	spin_unlock_irqrestore(&cgu->lock, flags);
238 
239 	if (i == timeout)
240 		return -EBUSY;
241 
242 	return 0;
243 }
244 
245 static void ingenic_pll_disable(struct clk_hw *hw)
246 {
247 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
248 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
249 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
250 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
251 	unsigned long flags;
252 	u32 ctl;
253 
254 	spin_lock_irqsave(&cgu->lock, flags);
255 	ctl = readl(cgu->base + pll_info->reg);
256 
257 	ctl &= ~BIT(pll_info->enable_bit);
258 
259 	writel(ctl, cgu->base + pll_info->reg);
260 	spin_unlock_irqrestore(&cgu->lock, flags);
261 }
262 
263 static int ingenic_pll_is_enabled(struct clk_hw *hw)
264 {
265 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
266 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
267 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
268 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
269 	u32 ctl;
270 
271 	ctl = readl(cgu->base + pll_info->reg);
272 
273 	return !!(ctl & BIT(pll_info->enable_bit));
274 }
275 
276 static const struct clk_ops ingenic_pll_ops = {
277 	.recalc_rate = ingenic_pll_recalc_rate,
278 	.round_rate = ingenic_pll_round_rate,
279 	.set_rate = ingenic_pll_set_rate,
280 
281 	.enable = ingenic_pll_enable,
282 	.disable = ingenic_pll_disable,
283 	.is_enabled = ingenic_pll_is_enabled,
284 };
285 
286 /*
287  * Operations for all non-PLL clocks
288  */
289 
290 static u8 ingenic_clk_get_parent(struct clk_hw *hw)
291 {
292 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
293 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
294 	const struct ingenic_cgu_clk_info *clk_info;
295 	u32 reg;
296 	u8 i, hw_idx, idx = 0;
297 
298 	clk_info = &cgu->clock_info[ingenic_clk->idx];
299 
300 	if (clk_info->type & CGU_CLK_MUX) {
301 		reg = readl(cgu->base + clk_info->mux.reg);
302 		hw_idx = (reg >> clk_info->mux.shift) &
303 			 GENMASK(clk_info->mux.bits - 1, 0);
304 
305 		/*
306 		 * Convert the hardware index to the parent index by skipping
307 		 * over any -1's in the parents array.
308 		 */
309 		for (i = 0; i < hw_idx; i++) {
310 			if (clk_info->parents[i] != -1)
311 				idx++;
312 		}
313 	}
314 
315 	return idx;
316 }
317 
318 static int ingenic_clk_set_parent(struct clk_hw *hw, u8 idx)
319 {
320 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
321 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
322 	const struct ingenic_cgu_clk_info *clk_info;
323 	unsigned long flags;
324 	u8 curr_idx, hw_idx, num_poss;
325 	u32 reg, mask;
326 
327 	clk_info = &cgu->clock_info[ingenic_clk->idx];
328 
329 	if (clk_info->type & CGU_CLK_MUX) {
330 		/*
331 		 * Convert the parent index to the hardware index by adding
332 		 * 1 for any -1 in the parents array preceding the given
333 		 * index. That is, we want the index of idx'th entry in
334 		 * clk_info->parents which does not equal -1.
335 		 */
336 		hw_idx = curr_idx = 0;
337 		num_poss = 1 << clk_info->mux.bits;
338 		for (; hw_idx < num_poss; hw_idx++) {
339 			if (clk_info->parents[hw_idx] == -1)
340 				continue;
341 			if (curr_idx == idx)
342 				break;
343 			curr_idx++;
344 		}
345 
346 		/* idx should always be a valid parent */
347 		BUG_ON(curr_idx != idx);
348 
349 		mask = GENMASK(clk_info->mux.bits - 1, 0);
350 		mask <<= clk_info->mux.shift;
351 
352 		spin_lock_irqsave(&cgu->lock, flags);
353 
354 		/* write the register */
355 		reg = readl(cgu->base + clk_info->mux.reg);
356 		reg &= ~mask;
357 		reg |= hw_idx << clk_info->mux.shift;
358 		writel(reg, cgu->base + clk_info->mux.reg);
359 
360 		spin_unlock_irqrestore(&cgu->lock, flags);
361 		return 0;
362 	}
363 
364 	return idx ? -EINVAL : 0;
365 }
366 
367 static unsigned long
368 ingenic_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
369 {
370 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
371 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
372 	const struct ingenic_cgu_clk_info *clk_info;
373 	unsigned long rate = parent_rate;
374 	u32 div_reg, div;
375 
376 	clk_info = &cgu->clock_info[ingenic_clk->idx];
377 
378 	if (clk_info->type & CGU_CLK_DIV) {
379 		div_reg = readl(cgu->base + clk_info->div.reg);
380 		div = (div_reg >> clk_info->div.shift) &
381 		      GENMASK(clk_info->div.bits - 1, 0);
382 
383 		if (clk_info->div.div_table)
384 			div = clk_info->div.div_table[div];
385 		else
386 			div = (div + 1) * clk_info->div.div;
387 
388 		rate /= div;
389 	} else if (clk_info->type & CGU_CLK_FIXDIV) {
390 		rate /= clk_info->fixdiv.div;
391 	}
392 
393 	return rate;
394 }
395 
396 static unsigned int
397 ingenic_clk_calc_hw_div(const struct ingenic_cgu_clk_info *clk_info,
398 			unsigned int div)
399 {
400 	unsigned int i;
401 
402 	for (i = 0; i < (1 << clk_info->div.bits)
403 				&& clk_info->div.div_table[i]; i++) {
404 		if (clk_info->div.div_table[i] >= div)
405 			return i;
406 	}
407 
408 	return i - 1;
409 }
410 
411 static unsigned
412 ingenic_clk_calc_div(const struct ingenic_cgu_clk_info *clk_info,
413 		     unsigned long parent_rate, unsigned long req_rate)
414 {
415 	unsigned int div, hw_div;
416 
417 	/* calculate the divide */
418 	div = DIV_ROUND_UP(parent_rate, req_rate);
419 
420 	if (clk_info->div.div_table) {
421 		hw_div = ingenic_clk_calc_hw_div(clk_info, div);
422 
423 		return clk_info->div.div_table[hw_div];
424 	}
425 
426 	/* Impose hardware constraints */
427 	div = min_t(unsigned, div, 1 << clk_info->div.bits);
428 	div = max_t(unsigned, div, 1);
429 
430 	/*
431 	 * If the divider value itself must be divided before being written to
432 	 * the divider register, we must ensure we don't have any bits set that
433 	 * would be lost as a result of doing so.
434 	 */
435 	div /= clk_info->div.div;
436 	div *= clk_info->div.div;
437 
438 	return div;
439 }
440 
441 static long
442 ingenic_clk_round_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 	unsigned int div = 1;
449 
450 	clk_info = &cgu->clock_info[ingenic_clk->idx];
451 
452 	if (clk_info->type & CGU_CLK_DIV)
453 		div = ingenic_clk_calc_div(clk_info, *parent_rate, req_rate);
454 	else if (clk_info->type & CGU_CLK_FIXDIV)
455 		div = clk_info->fixdiv.div;
456 
457 	return DIV_ROUND_UP(*parent_rate, div);
458 }
459 
460 static int
461 ingenic_clk_set_rate(struct clk_hw *hw, unsigned long req_rate,
462 		     unsigned long parent_rate)
463 {
464 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
465 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
466 	const struct ingenic_cgu_clk_info *clk_info;
467 	const unsigned timeout = 100;
468 	unsigned long rate, flags;
469 	unsigned int hw_div, div, i;
470 	u32 reg, mask;
471 	int ret = 0;
472 
473 	clk_info = &cgu->clock_info[ingenic_clk->idx];
474 
475 	if (clk_info->type & CGU_CLK_DIV) {
476 		div = ingenic_clk_calc_div(clk_info, parent_rate, req_rate);
477 		rate = DIV_ROUND_UP(parent_rate, div);
478 
479 		if (rate != req_rate)
480 			return -EINVAL;
481 
482 		if (clk_info->div.div_table)
483 			hw_div = ingenic_clk_calc_hw_div(clk_info, div);
484 		else
485 			hw_div = ((div / clk_info->div.div) - 1);
486 
487 		spin_lock_irqsave(&cgu->lock, flags);
488 		reg = readl(cgu->base + clk_info->div.reg);
489 
490 		/* update the divide */
491 		mask = GENMASK(clk_info->div.bits - 1, 0);
492 		reg &= ~(mask << clk_info->div.shift);
493 		reg |= hw_div << clk_info->div.shift;
494 
495 		/* clear the stop bit */
496 		if (clk_info->div.stop_bit != -1)
497 			reg &= ~BIT(clk_info->div.stop_bit);
498 
499 		/* set the change enable bit */
500 		if (clk_info->div.ce_bit != -1)
501 			reg |= BIT(clk_info->div.ce_bit);
502 
503 		/* update the hardware */
504 		writel(reg, cgu->base + clk_info->div.reg);
505 
506 		/* wait for the change to take effect */
507 		if (clk_info->div.busy_bit != -1) {
508 			for (i = 0; i < timeout; i++) {
509 				reg = readl(cgu->base + clk_info->div.reg);
510 				if (!(reg & BIT(clk_info->div.busy_bit)))
511 					break;
512 				mdelay(1);
513 			}
514 			if (i == timeout)
515 				ret = -EBUSY;
516 		}
517 
518 		spin_unlock_irqrestore(&cgu->lock, flags);
519 		return ret;
520 	}
521 
522 	return -EINVAL;
523 }
524 
525 static int ingenic_clk_enable(struct clk_hw *hw)
526 {
527 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
528 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
529 	const struct ingenic_cgu_clk_info *clk_info;
530 	unsigned long flags;
531 
532 	clk_info = &cgu->clock_info[ingenic_clk->idx];
533 
534 	if (clk_info->type & CGU_CLK_GATE) {
535 		/* ungate the clock */
536 		spin_lock_irqsave(&cgu->lock, flags);
537 		ingenic_cgu_gate_set(cgu, &clk_info->gate, false);
538 		spin_unlock_irqrestore(&cgu->lock, flags);
539 
540 		if (clk_info->gate.delay_us)
541 			udelay(clk_info->gate.delay_us);
542 	}
543 
544 	return 0;
545 }
546 
547 static void ingenic_clk_disable(struct clk_hw *hw)
548 {
549 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
550 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
551 	const struct ingenic_cgu_clk_info *clk_info;
552 	unsigned long flags;
553 
554 	clk_info = &cgu->clock_info[ingenic_clk->idx];
555 
556 	if (clk_info->type & CGU_CLK_GATE) {
557 		/* gate the clock */
558 		spin_lock_irqsave(&cgu->lock, flags);
559 		ingenic_cgu_gate_set(cgu, &clk_info->gate, true);
560 		spin_unlock_irqrestore(&cgu->lock, flags);
561 	}
562 }
563 
564 static int ingenic_clk_is_enabled(struct clk_hw *hw)
565 {
566 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
567 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
568 	const struct ingenic_cgu_clk_info *clk_info;
569 	int enabled = 1;
570 
571 	clk_info = &cgu->clock_info[ingenic_clk->idx];
572 
573 	if (clk_info->type & CGU_CLK_GATE)
574 		enabled = !ingenic_cgu_gate_get(cgu, &clk_info->gate);
575 
576 	return enabled;
577 }
578 
579 static const struct clk_ops ingenic_clk_ops = {
580 	.get_parent = ingenic_clk_get_parent,
581 	.set_parent = ingenic_clk_set_parent,
582 
583 	.recalc_rate = ingenic_clk_recalc_rate,
584 	.round_rate = ingenic_clk_round_rate,
585 	.set_rate = ingenic_clk_set_rate,
586 
587 	.enable = ingenic_clk_enable,
588 	.disable = ingenic_clk_disable,
589 	.is_enabled = ingenic_clk_is_enabled,
590 };
591 
592 /*
593  * Setup functions.
594  */
595 
596 static int ingenic_register_clock(struct ingenic_cgu *cgu, unsigned idx)
597 {
598 	const struct ingenic_cgu_clk_info *clk_info = &cgu->clock_info[idx];
599 	struct clk_init_data clk_init;
600 	struct ingenic_clk *ingenic_clk = NULL;
601 	struct clk *clk, *parent;
602 	const char *parent_names[4];
603 	unsigned caps, i, num_possible;
604 	int err = -EINVAL;
605 
606 	BUILD_BUG_ON(ARRAY_SIZE(clk_info->parents) > ARRAY_SIZE(parent_names));
607 
608 	if (clk_info->type == CGU_CLK_EXT) {
609 		clk = of_clk_get_by_name(cgu->np, clk_info->name);
610 		if (IS_ERR(clk)) {
611 			pr_err("%s: no external clock '%s' provided\n",
612 			       __func__, clk_info->name);
613 			err = -ENODEV;
614 			goto out;
615 		}
616 		err = clk_register_clkdev(clk, clk_info->name, NULL);
617 		if (err) {
618 			clk_put(clk);
619 			goto out;
620 		}
621 		cgu->clocks.clks[idx] = clk;
622 		return 0;
623 	}
624 
625 	if (!clk_info->type) {
626 		pr_err("%s: no clock type specified for '%s'\n", __func__,
627 		       clk_info->name);
628 		goto out;
629 	}
630 
631 	ingenic_clk = kzalloc(sizeof(*ingenic_clk), GFP_KERNEL);
632 	if (!ingenic_clk) {
633 		err = -ENOMEM;
634 		goto out;
635 	}
636 
637 	ingenic_clk->hw.init = &clk_init;
638 	ingenic_clk->cgu = cgu;
639 	ingenic_clk->idx = idx;
640 
641 	clk_init.name = clk_info->name;
642 	clk_init.flags = 0;
643 	clk_init.parent_names = parent_names;
644 
645 	caps = clk_info->type;
646 
647 	if (caps & (CGU_CLK_MUX | CGU_CLK_CUSTOM)) {
648 		clk_init.num_parents = 0;
649 
650 		if (caps & CGU_CLK_MUX)
651 			num_possible = 1 << clk_info->mux.bits;
652 		else
653 			num_possible = ARRAY_SIZE(clk_info->parents);
654 
655 		for (i = 0; i < num_possible; i++) {
656 			if (clk_info->parents[i] == -1)
657 				continue;
658 
659 			parent = cgu->clocks.clks[clk_info->parents[i]];
660 			parent_names[clk_init.num_parents] =
661 				__clk_get_name(parent);
662 			clk_init.num_parents++;
663 		}
664 
665 		BUG_ON(!clk_init.num_parents);
666 		BUG_ON(clk_init.num_parents > ARRAY_SIZE(parent_names));
667 	} else {
668 		BUG_ON(clk_info->parents[0] == -1);
669 		clk_init.num_parents = 1;
670 		parent = cgu->clocks.clks[clk_info->parents[0]];
671 		parent_names[0] = __clk_get_name(parent);
672 	}
673 
674 	if (caps & CGU_CLK_CUSTOM) {
675 		clk_init.ops = clk_info->custom.clk_ops;
676 
677 		caps &= ~CGU_CLK_CUSTOM;
678 
679 		if (caps) {
680 			pr_err("%s: custom clock may not be combined with type 0x%x\n",
681 			       __func__, caps);
682 			goto out;
683 		}
684 	} else if (caps & CGU_CLK_PLL) {
685 		clk_init.ops = &ingenic_pll_ops;
686 		clk_init.flags |= CLK_SET_RATE_GATE;
687 
688 		caps &= ~CGU_CLK_PLL;
689 
690 		if (caps) {
691 			pr_err("%s: PLL may not be combined with type 0x%x\n",
692 			       __func__, caps);
693 			goto out;
694 		}
695 	} else {
696 		clk_init.ops = &ingenic_clk_ops;
697 	}
698 
699 	/* nothing to do for gates or fixed dividers */
700 	caps &= ~(CGU_CLK_GATE | CGU_CLK_FIXDIV);
701 
702 	if (caps & CGU_CLK_MUX) {
703 		if (!(caps & CGU_CLK_MUX_GLITCHFREE))
704 			clk_init.flags |= CLK_SET_PARENT_GATE;
705 
706 		caps &= ~(CGU_CLK_MUX | CGU_CLK_MUX_GLITCHFREE);
707 	}
708 
709 	if (caps & CGU_CLK_DIV) {
710 		caps &= ~CGU_CLK_DIV;
711 	} else {
712 		/* pass rate changes to the parent clock */
713 		clk_init.flags |= CLK_SET_RATE_PARENT;
714 	}
715 
716 	if (caps) {
717 		pr_err("%s: unknown clock type 0x%x\n", __func__, caps);
718 		goto out;
719 	}
720 
721 	clk = clk_register(NULL, &ingenic_clk->hw);
722 	if (IS_ERR(clk)) {
723 		pr_err("%s: failed to register clock '%s'\n", __func__,
724 		       clk_info->name);
725 		err = PTR_ERR(clk);
726 		goto out;
727 	}
728 
729 	err = clk_register_clkdev(clk, clk_info->name, NULL);
730 	if (err)
731 		goto out;
732 
733 	cgu->clocks.clks[idx] = clk;
734 out:
735 	if (err)
736 		kfree(ingenic_clk);
737 	return err;
738 }
739 
740 struct ingenic_cgu *
741 ingenic_cgu_new(const struct ingenic_cgu_clk_info *clock_info,
742 		unsigned num_clocks, struct device_node *np)
743 {
744 	struct ingenic_cgu *cgu;
745 
746 	cgu = kzalloc(sizeof(*cgu), GFP_KERNEL);
747 	if (!cgu)
748 		goto err_out;
749 
750 	cgu->base = of_iomap(np, 0);
751 	if (!cgu->base) {
752 		pr_err("%s: failed to map CGU registers\n", __func__);
753 		goto err_out_free;
754 	}
755 
756 	cgu->np = np;
757 	cgu->clock_info = clock_info;
758 	cgu->clocks.clk_num = num_clocks;
759 
760 	spin_lock_init(&cgu->lock);
761 
762 	return cgu;
763 
764 err_out_free:
765 	kfree(cgu);
766 err_out:
767 	return NULL;
768 }
769 
770 int ingenic_cgu_register_clocks(struct ingenic_cgu *cgu)
771 {
772 	unsigned i;
773 	int err;
774 
775 	cgu->clocks.clks = kcalloc(cgu->clocks.clk_num, sizeof(struct clk *),
776 				   GFP_KERNEL);
777 	if (!cgu->clocks.clks) {
778 		err = -ENOMEM;
779 		goto err_out;
780 	}
781 
782 	for (i = 0; i < cgu->clocks.clk_num; i++) {
783 		err = ingenic_register_clock(cgu, i);
784 		if (err)
785 			goto err_out_unregister;
786 	}
787 
788 	err = of_clk_add_provider(cgu->np, of_clk_src_onecell_get,
789 				  &cgu->clocks);
790 	if (err)
791 		goto err_out_unregister;
792 
793 	return 0;
794 
795 err_out_unregister:
796 	for (i = 0; i < cgu->clocks.clk_num; i++) {
797 		if (!cgu->clocks.clks[i])
798 			continue;
799 		if (cgu->clock_info[i].type & CGU_CLK_EXT)
800 			clk_put(cgu->clocks.clks[i]);
801 		else
802 			clk_unregister(cgu->clocks.clks[i]);
803 	}
804 	kfree(cgu->clocks.clks);
805 err_out:
806 	return err;
807 }
808