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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
ingenic_cgu_gate_get(struct ingenic_cgu * cgu,const struct ingenic_cgu_gate_info * info)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
ingenic_cgu_gate_set(struct ingenic_cgu * cgu,const struct ingenic_cgu_gate_info * info,bool val)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
ingenic_pll_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)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 	unsigned long flags;
80 	u32 ctl;
81 
82 	clk_info = &cgu->clock_info[ingenic_clk->idx];
83 	BUG_ON(clk_info->type != CGU_CLK_PLL);
84 	pll_info = &clk_info->pll;
85 
86 	spin_lock_irqsave(&cgu->lock, flags);
87 	ctl = readl(cgu->base + pll_info->reg);
88 	spin_unlock_irqrestore(&cgu->lock, flags);
89 
90 	m = (ctl >> pll_info->m_shift) & GENMASK(pll_info->m_bits - 1, 0);
91 	m += pll_info->m_offset;
92 	n = (ctl >> pll_info->n_shift) & GENMASK(pll_info->n_bits - 1, 0);
93 	n += pll_info->n_offset;
94 	od_enc = ctl >> pll_info->od_shift;
95 	od_enc &= GENMASK(pll_info->od_bits - 1, 0);
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, n * od);
110 }
111 
112 static unsigned long
ingenic_pll_calc(const struct ingenic_cgu_clk_info * clk_info,unsigned long rate,unsigned long parent_rate,unsigned * pm,unsigned * pn,unsigned * pod)113 ingenic_pll_calc(const struct ingenic_cgu_clk_info *clk_info,
114 		 unsigned long rate, unsigned long parent_rate,
115 		 unsigned *pm, unsigned *pn, unsigned *pod)
116 {
117 	const struct ingenic_cgu_pll_info *pll_info;
118 	unsigned m, n, od;
119 
120 	pll_info = &clk_info->pll;
121 	od = 1;
122 
123 	/*
124 	 * The frequency after the input divider must be between 10 and 50 MHz.
125 	 * The highest divider yields the best resolution.
126 	 */
127 	n = parent_rate / (10 * MHZ);
128 	n = min_t(unsigned, n, 1 << clk_info->pll.n_bits);
129 	n = max_t(unsigned, n, pll_info->n_offset);
130 
131 	m = (rate / MHZ) * od * n / (parent_rate / MHZ);
132 	m = min_t(unsigned, m, 1 << clk_info->pll.m_bits);
133 	m = max_t(unsigned, m, pll_info->m_offset);
134 
135 	if (pm)
136 		*pm = m;
137 	if (pn)
138 		*pn = n;
139 	if (pod)
140 		*pod = od;
141 
142 	return div_u64((u64)parent_rate * m, n * od);
143 }
144 
to_clk_info(struct ingenic_clk * ingenic_clk)145 static inline const struct ingenic_cgu_clk_info *to_clk_info(
146 		struct ingenic_clk *ingenic_clk)
147 {
148 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
149 	const struct ingenic_cgu_clk_info *clk_info;
150 
151 	clk_info = &cgu->clock_info[ingenic_clk->idx];
152 	BUG_ON(clk_info->type != CGU_CLK_PLL);
153 
154 	return clk_info;
155 }
156 
157 static long
ingenic_pll_round_rate(struct clk_hw * hw,unsigned long req_rate,unsigned long * prate)158 ingenic_pll_round_rate(struct clk_hw *hw, unsigned long req_rate,
159 		       unsigned long *prate)
160 {
161 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
162 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
163 
164 	return ingenic_pll_calc(clk_info, req_rate, *prate, NULL, NULL, NULL);
165 }
166 
167 static int
ingenic_pll_set_rate(struct clk_hw * hw,unsigned long req_rate,unsigned long parent_rate)168 ingenic_pll_set_rate(struct clk_hw *hw, unsigned long req_rate,
169 		     unsigned long parent_rate)
170 {
171 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
172 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
173 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
174 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
175 	unsigned long rate, flags;
176 	unsigned int m, n, od;
177 	u32 ctl;
178 
179 	rate = ingenic_pll_calc(clk_info, req_rate, parent_rate,
180 			       &m, &n, &od);
181 	if (rate != req_rate)
182 		pr_info("ingenic-cgu: request '%s' rate %luHz, actual %luHz\n",
183 			clk_info->name, req_rate, rate);
184 
185 	spin_lock_irqsave(&cgu->lock, flags);
186 	ctl = readl(cgu->base + pll_info->reg);
187 
188 	ctl &= ~(GENMASK(pll_info->m_bits - 1, 0) << pll_info->m_shift);
189 	ctl |= (m - pll_info->m_offset) << pll_info->m_shift;
190 
191 	ctl &= ~(GENMASK(pll_info->n_bits - 1, 0) << pll_info->n_shift);
192 	ctl |= (n - pll_info->n_offset) << pll_info->n_shift;
193 
194 	ctl &= ~(GENMASK(pll_info->od_bits - 1, 0) << pll_info->od_shift);
195 	ctl |= pll_info->od_encoding[od - 1] << pll_info->od_shift;
196 
197 	writel(ctl, cgu->base + pll_info->reg);
198 	spin_unlock_irqrestore(&cgu->lock, flags);
199 
200 	return 0;
201 }
202 
ingenic_pll_enable(struct clk_hw * hw)203 static int ingenic_pll_enable(struct clk_hw *hw)
204 {
205 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
206 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
207 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
208 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
209 	const unsigned int timeout = 100;
210 	unsigned long flags;
211 	unsigned int i;
212 	u32 ctl;
213 
214 	spin_lock_irqsave(&cgu->lock, flags);
215 	ctl = readl(cgu->base + pll_info->reg);
216 
217 	ctl &= ~BIT(pll_info->bypass_bit);
218 	ctl |= BIT(pll_info->enable_bit);
219 
220 	writel(ctl, cgu->base + pll_info->reg);
221 
222 	/* wait for the PLL to stabilise */
223 	for (i = 0; i < timeout; i++) {
224 		ctl = readl(cgu->base + pll_info->reg);
225 		if (ctl & BIT(pll_info->stable_bit))
226 			break;
227 		mdelay(1);
228 	}
229 
230 	spin_unlock_irqrestore(&cgu->lock, flags);
231 
232 	if (i == timeout)
233 		return -EBUSY;
234 
235 	return 0;
236 }
237 
ingenic_pll_disable(struct clk_hw * hw)238 static void ingenic_pll_disable(struct clk_hw *hw)
239 {
240 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
241 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
242 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
243 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
244 	unsigned long flags;
245 	u32 ctl;
246 
247 	spin_lock_irqsave(&cgu->lock, flags);
248 	ctl = readl(cgu->base + pll_info->reg);
249 
250 	ctl &= ~BIT(pll_info->enable_bit);
251 
252 	writel(ctl, cgu->base + pll_info->reg);
253 	spin_unlock_irqrestore(&cgu->lock, flags);
254 }
255 
ingenic_pll_is_enabled(struct clk_hw * hw)256 static int ingenic_pll_is_enabled(struct clk_hw *hw)
257 {
258 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
259 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
260 	const struct ingenic_cgu_clk_info *clk_info = to_clk_info(ingenic_clk);
261 	const struct ingenic_cgu_pll_info *pll_info = &clk_info->pll;
262 	unsigned long flags;
263 	u32 ctl;
264 
265 	spin_lock_irqsave(&cgu->lock, flags);
266 	ctl = readl(cgu->base + pll_info->reg);
267 	spin_unlock_irqrestore(&cgu->lock, flags);
268 
269 	return !!(ctl & BIT(pll_info->enable_bit));
270 }
271 
272 static const struct clk_ops ingenic_pll_ops = {
273 	.recalc_rate = ingenic_pll_recalc_rate,
274 	.round_rate = ingenic_pll_round_rate,
275 	.set_rate = ingenic_pll_set_rate,
276 
277 	.enable = ingenic_pll_enable,
278 	.disable = ingenic_pll_disable,
279 	.is_enabled = ingenic_pll_is_enabled,
280 };
281 
282 /*
283  * Operations for all non-PLL clocks
284  */
285 
ingenic_clk_get_parent(struct clk_hw * hw)286 static u8 ingenic_clk_get_parent(struct clk_hw *hw)
287 {
288 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
289 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
290 	const struct ingenic_cgu_clk_info *clk_info;
291 	u32 reg;
292 	u8 i, hw_idx, idx = 0;
293 
294 	clk_info = &cgu->clock_info[ingenic_clk->idx];
295 
296 	if (clk_info->type & CGU_CLK_MUX) {
297 		reg = readl(cgu->base + clk_info->mux.reg);
298 		hw_idx = (reg >> clk_info->mux.shift) &
299 			 GENMASK(clk_info->mux.bits - 1, 0);
300 
301 		/*
302 		 * Convert the hardware index to the parent index by skipping
303 		 * over any -1's in the parents array.
304 		 */
305 		for (i = 0; i < hw_idx; i++) {
306 			if (clk_info->parents[i] != -1)
307 				idx++;
308 		}
309 	}
310 
311 	return idx;
312 }
313 
ingenic_clk_set_parent(struct clk_hw * hw,u8 idx)314 static int ingenic_clk_set_parent(struct clk_hw *hw, u8 idx)
315 {
316 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
317 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
318 	const struct ingenic_cgu_clk_info *clk_info;
319 	unsigned long flags;
320 	u8 curr_idx, hw_idx, num_poss;
321 	u32 reg, mask;
322 
323 	clk_info = &cgu->clock_info[ingenic_clk->idx];
324 
325 	if (clk_info->type & CGU_CLK_MUX) {
326 		/*
327 		 * Convert the parent index to the hardware index by adding
328 		 * 1 for any -1 in the parents array preceding the given
329 		 * index. That is, we want the index of idx'th entry in
330 		 * clk_info->parents which does not equal -1.
331 		 */
332 		hw_idx = curr_idx = 0;
333 		num_poss = 1 << clk_info->mux.bits;
334 		for (; hw_idx < num_poss; hw_idx++) {
335 			if (clk_info->parents[hw_idx] == -1)
336 				continue;
337 			if (curr_idx == idx)
338 				break;
339 			curr_idx++;
340 		}
341 
342 		/* idx should always be a valid parent */
343 		BUG_ON(curr_idx != idx);
344 
345 		mask = GENMASK(clk_info->mux.bits - 1, 0);
346 		mask <<= clk_info->mux.shift;
347 
348 		spin_lock_irqsave(&cgu->lock, flags);
349 
350 		/* write the register */
351 		reg = readl(cgu->base + clk_info->mux.reg);
352 		reg &= ~mask;
353 		reg |= hw_idx << clk_info->mux.shift;
354 		writel(reg, cgu->base + clk_info->mux.reg);
355 
356 		spin_unlock_irqrestore(&cgu->lock, flags);
357 		return 0;
358 	}
359 
360 	return idx ? -EINVAL : 0;
361 }
362 
363 static unsigned long
ingenic_clk_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)364 ingenic_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
365 {
366 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
367 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
368 	const struct ingenic_cgu_clk_info *clk_info;
369 	unsigned long rate = parent_rate;
370 	u32 div_reg, div;
371 
372 	clk_info = &cgu->clock_info[ingenic_clk->idx];
373 
374 	if (clk_info->type & CGU_CLK_DIV) {
375 		div_reg = readl(cgu->base + clk_info->div.reg);
376 		div = (div_reg >> clk_info->div.shift) &
377 		      GENMASK(clk_info->div.bits - 1, 0);
378 
379 		if (clk_info->div.div_table)
380 			div = clk_info->div.div_table[div];
381 		else
382 			div = (div + 1) * clk_info->div.div;
383 
384 		rate /= div;
385 	} else if (clk_info->type & CGU_CLK_FIXDIV) {
386 		rate /= clk_info->fixdiv.div;
387 	}
388 
389 	return rate;
390 }
391 
392 static unsigned int
ingenic_clk_calc_hw_div(const struct ingenic_cgu_clk_info * clk_info,unsigned int div)393 ingenic_clk_calc_hw_div(const struct ingenic_cgu_clk_info *clk_info,
394 			unsigned int div)
395 {
396 	unsigned int i, best_i = 0, best = (unsigned int)-1;
397 
398 	for (i = 0; i < (1 << clk_info->div.bits)
399 				&& clk_info->div.div_table[i]; i++) {
400 		if (clk_info->div.div_table[i] >= div &&
401 		    clk_info->div.div_table[i] < best) {
402 			best = clk_info->div.div_table[i];
403 			best_i = i;
404 
405 			if (div == best)
406 				break;
407 		}
408 	}
409 
410 	return best_i;
411 }
412 
413 static unsigned
ingenic_clk_calc_div(const struct ingenic_cgu_clk_info * clk_info,unsigned long parent_rate,unsigned long req_rate)414 ingenic_clk_calc_div(const struct ingenic_cgu_clk_info *clk_info,
415 		     unsigned long parent_rate, unsigned long req_rate)
416 {
417 	unsigned int div, hw_div;
418 
419 	/* calculate the divide */
420 	div = DIV_ROUND_UP(parent_rate, req_rate);
421 
422 	if (clk_info->div.div_table) {
423 		hw_div = ingenic_clk_calc_hw_div(clk_info, div);
424 
425 		return clk_info->div.div_table[hw_div];
426 	}
427 
428 	/* Impose hardware constraints */
429 	div = clamp_t(unsigned int, div, clk_info->div.div,
430 		      clk_info->div.div << clk_info->div.bits);
431 
432 	/*
433 	 * If the divider value itself must be divided before being written to
434 	 * the divider register, we must ensure we don't have any bits set that
435 	 * would be lost as a result of doing so.
436 	 */
437 	div = DIV_ROUND_UP(div, clk_info->div.div);
438 	div *= clk_info->div.div;
439 
440 	return div;
441 }
442 
443 static long
ingenic_clk_round_rate(struct clk_hw * hw,unsigned long req_rate,unsigned long * parent_rate)444 ingenic_clk_round_rate(struct clk_hw *hw, unsigned long req_rate,
445 		       unsigned long *parent_rate)
446 {
447 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
448 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
449 	const struct ingenic_cgu_clk_info *clk_info;
450 	unsigned int div = 1;
451 
452 	clk_info = &cgu->clock_info[ingenic_clk->idx];
453 
454 	if (clk_info->type & CGU_CLK_DIV)
455 		div = ingenic_clk_calc_div(clk_info, *parent_rate, req_rate);
456 	else if (clk_info->type & CGU_CLK_FIXDIV)
457 		div = clk_info->fixdiv.div;
458 
459 	return DIV_ROUND_UP(*parent_rate, div);
460 }
461 
462 static int
ingenic_clk_set_rate(struct clk_hw * hw,unsigned long req_rate,unsigned long parent_rate)463 ingenic_clk_set_rate(struct clk_hw *hw, unsigned long req_rate,
464 		     unsigned long parent_rate)
465 {
466 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
467 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
468 	const struct ingenic_cgu_clk_info *clk_info;
469 	const unsigned timeout = 100;
470 	unsigned long rate, flags;
471 	unsigned int hw_div, div, i;
472 	u32 reg, mask;
473 	int ret = 0;
474 
475 	clk_info = &cgu->clock_info[ingenic_clk->idx];
476 
477 	if (clk_info->type & CGU_CLK_DIV) {
478 		div = ingenic_clk_calc_div(clk_info, parent_rate, req_rate);
479 		rate = DIV_ROUND_UP(parent_rate, div);
480 
481 		if (rate != req_rate)
482 			return -EINVAL;
483 
484 		if (clk_info->div.div_table)
485 			hw_div = ingenic_clk_calc_hw_div(clk_info, div);
486 		else
487 			hw_div = ((div / clk_info->div.div) - 1);
488 
489 		spin_lock_irqsave(&cgu->lock, flags);
490 		reg = readl(cgu->base + clk_info->div.reg);
491 
492 		/* update the divide */
493 		mask = GENMASK(clk_info->div.bits - 1, 0);
494 		reg &= ~(mask << clk_info->div.shift);
495 		reg |= hw_div << clk_info->div.shift;
496 
497 		/* clear the stop bit */
498 		if (clk_info->div.stop_bit != -1)
499 			reg &= ~BIT(clk_info->div.stop_bit);
500 
501 		/* set the change enable bit */
502 		if (clk_info->div.ce_bit != -1)
503 			reg |= BIT(clk_info->div.ce_bit);
504 
505 		/* update the hardware */
506 		writel(reg, cgu->base + clk_info->div.reg);
507 
508 		/* wait for the change to take effect */
509 		if (clk_info->div.busy_bit != -1) {
510 			for (i = 0; i < timeout; i++) {
511 				reg = readl(cgu->base + clk_info->div.reg);
512 				if (!(reg & BIT(clk_info->div.busy_bit)))
513 					break;
514 				mdelay(1);
515 			}
516 			if (i == timeout)
517 				ret = -EBUSY;
518 		}
519 
520 		spin_unlock_irqrestore(&cgu->lock, flags);
521 		return ret;
522 	}
523 
524 	return -EINVAL;
525 }
526 
ingenic_clk_enable(struct clk_hw * hw)527 static int ingenic_clk_enable(struct clk_hw *hw)
528 {
529 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
530 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
531 	const struct ingenic_cgu_clk_info *clk_info;
532 	unsigned long flags;
533 
534 	clk_info = &cgu->clock_info[ingenic_clk->idx];
535 
536 	if (clk_info->type & CGU_CLK_GATE) {
537 		/* ungate the clock */
538 		spin_lock_irqsave(&cgu->lock, flags);
539 		ingenic_cgu_gate_set(cgu, &clk_info->gate, false);
540 		spin_unlock_irqrestore(&cgu->lock, flags);
541 
542 		if (clk_info->gate.delay_us)
543 			udelay(clk_info->gate.delay_us);
544 	}
545 
546 	return 0;
547 }
548 
ingenic_clk_disable(struct clk_hw * hw)549 static void ingenic_clk_disable(struct clk_hw *hw)
550 {
551 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
552 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
553 	const struct ingenic_cgu_clk_info *clk_info;
554 	unsigned long flags;
555 
556 	clk_info = &cgu->clock_info[ingenic_clk->idx];
557 
558 	if (clk_info->type & CGU_CLK_GATE) {
559 		/* gate the clock */
560 		spin_lock_irqsave(&cgu->lock, flags);
561 		ingenic_cgu_gate_set(cgu, &clk_info->gate, true);
562 		spin_unlock_irqrestore(&cgu->lock, flags);
563 	}
564 }
565 
ingenic_clk_is_enabled(struct clk_hw * hw)566 static int ingenic_clk_is_enabled(struct clk_hw *hw)
567 {
568 	struct ingenic_clk *ingenic_clk = to_ingenic_clk(hw);
569 	struct ingenic_cgu *cgu = ingenic_clk->cgu;
570 	const struct ingenic_cgu_clk_info *clk_info;
571 	unsigned long flags;
572 	int enabled = 1;
573 
574 	clk_info = &cgu->clock_info[ingenic_clk->idx];
575 
576 	if (clk_info->type & CGU_CLK_GATE) {
577 		spin_lock_irqsave(&cgu->lock, flags);
578 		enabled = !ingenic_cgu_gate_get(cgu, &clk_info->gate);
579 		spin_unlock_irqrestore(&cgu->lock, flags);
580 	}
581 
582 	return enabled;
583 }
584 
585 static const struct clk_ops ingenic_clk_ops = {
586 	.get_parent = ingenic_clk_get_parent,
587 	.set_parent = ingenic_clk_set_parent,
588 
589 	.recalc_rate = ingenic_clk_recalc_rate,
590 	.round_rate = ingenic_clk_round_rate,
591 	.set_rate = ingenic_clk_set_rate,
592 
593 	.enable = ingenic_clk_enable,
594 	.disable = ingenic_clk_disable,
595 	.is_enabled = ingenic_clk_is_enabled,
596 };
597 
598 /*
599  * Setup functions.
600  */
601 
ingenic_register_clock(struct ingenic_cgu * cgu,unsigned idx)602 static int ingenic_register_clock(struct ingenic_cgu *cgu, unsigned idx)
603 {
604 	const struct ingenic_cgu_clk_info *clk_info = &cgu->clock_info[idx];
605 	struct clk_init_data clk_init;
606 	struct ingenic_clk *ingenic_clk = NULL;
607 	struct clk *clk, *parent;
608 	const char *parent_names[4];
609 	unsigned caps, i, num_possible;
610 	int err = -EINVAL;
611 
612 	BUILD_BUG_ON(ARRAY_SIZE(clk_info->parents) > ARRAY_SIZE(parent_names));
613 
614 	if (clk_info->type == CGU_CLK_EXT) {
615 		clk = of_clk_get_by_name(cgu->np, clk_info->name);
616 		if (IS_ERR(clk)) {
617 			pr_err("%s: no external clock '%s' provided\n",
618 			       __func__, clk_info->name);
619 			err = -ENODEV;
620 			goto out;
621 		}
622 		err = clk_register_clkdev(clk, clk_info->name, NULL);
623 		if (err) {
624 			clk_put(clk);
625 			goto out;
626 		}
627 		cgu->clocks.clks[idx] = clk;
628 		return 0;
629 	}
630 
631 	if (!clk_info->type) {
632 		pr_err("%s: no clock type specified for '%s'\n", __func__,
633 		       clk_info->name);
634 		goto out;
635 	}
636 
637 	ingenic_clk = kzalloc(sizeof(*ingenic_clk), GFP_KERNEL);
638 	if (!ingenic_clk) {
639 		err = -ENOMEM;
640 		goto out;
641 	}
642 
643 	ingenic_clk->hw.init = &clk_init;
644 	ingenic_clk->cgu = cgu;
645 	ingenic_clk->idx = idx;
646 
647 	clk_init.name = clk_info->name;
648 	clk_init.flags = 0;
649 	clk_init.parent_names = parent_names;
650 
651 	caps = clk_info->type;
652 
653 	if (caps & (CGU_CLK_MUX | CGU_CLK_CUSTOM)) {
654 		clk_init.num_parents = 0;
655 
656 		if (caps & CGU_CLK_MUX)
657 			num_possible = 1 << clk_info->mux.bits;
658 		else
659 			num_possible = ARRAY_SIZE(clk_info->parents);
660 
661 		for (i = 0; i < num_possible; i++) {
662 			if (clk_info->parents[i] == -1)
663 				continue;
664 
665 			parent = cgu->clocks.clks[clk_info->parents[i]];
666 			parent_names[clk_init.num_parents] =
667 				__clk_get_name(parent);
668 			clk_init.num_parents++;
669 		}
670 
671 		BUG_ON(!clk_init.num_parents);
672 		BUG_ON(clk_init.num_parents > ARRAY_SIZE(parent_names));
673 	} else {
674 		BUG_ON(clk_info->parents[0] == -1);
675 		clk_init.num_parents = 1;
676 		parent = cgu->clocks.clks[clk_info->parents[0]];
677 		parent_names[0] = __clk_get_name(parent);
678 	}
679 
680 	if (caps & CGU_CLK_CUSTOM) {
681 		clk_init.ops = clk_info->custom.clk_ops;
682 
683 		caps &= ~CGU_CLK_CUSTOM;
684 
685 		if (caps) {
686 			pr_err("%s: custom clock may not be combined with type 0x%x\n",
687 			       __func__, caps);
688 			goto out;
689 		}
690 	} else if (caps & CGU_CLK_PLL) {
691 		clk_init.ops = &ingenic_pll_ops;
692 		clk_init.flags |= CLK_SET_RATE_GATE;
693 
694 		caps &= ~CGU_CLK_PLL;
695 
696 		if (caps) {
697 			pr_err("%s: PLL may not be combined with type 0x%x\n",
698 			       __func__, caps);
699 			goto out;
700 		}
701 	} else {
702 		clk_init.ops = &ingenic_clk_ops;
703 	}
704 
705 	/* nothing to do for gates or fixed dividers */
706 	caps &= ~(CGU_CLK_GATE | CGU_CLK_FIXDIV);
707 
708 	if (caps & CGU_CLK_MUX) {
709 		if (!(caps & CGU_CLK_MUX_GLITCHFREE))
710 			clk_init.flags |= CLK_SET_PARENT_GATE;
711 
712 		caps &= ~(CGU_CLK_MUX | CGU_CLK_MUX_GLITCHFREE);
713 	}
714 
715 	if (caps & CGU_CLK_DIV) {
716 		caps &= ~CGU_CLK_DIV;
717 	} else {
718 		/* pass rate changes to the parent clock */
719 		clk_init.flags |= CLK_SET_RATE_PARENT;
720 	}
721 
722 	if (caps) {
723 		pr_err("%s: unknown clock type 0x%x\n", __func__, caps);
724 		goto out;
725 	}
726 
727 	clk = clk_register(NULL, &ingenic_clk->hw);
728 	if (IS_ERR(clk)) {
729 		pr_err("%s: failed to register clock '%s'\n", __func__,
730 		       clk_info->name);
731 		err = PTR_ERR(clk);
732 		goto out;
733 	}
734 
735 	err = clk_register_clkdev(clk, clk_info->name, NULL);
736 	if (err)
737 		goto out;
738 
739 	cgu->clocks.clks[idx] = clk;
740 out:
741 	if (err)
742 		kfree(ingenic_clk);
743 	return err;
744 }
745 
746 struct ingenic_cgu *
ingenic_cgu_new(const struct ingenic_cgu_clk_info * clock_info,unsigned num_clocks,struct device_node * np)747 ingenic_cgu_new(const struct ingenic_cgu_clk_info *clock_info,
748 		unsigned num_clocks, struct device_node *np)
749 {
750 	struct ingenic_cgu *cgu;
751 
752 	cgu = kzalloc(sizeof(*cgu), GFP_KERNEL);
753 	if (!cgu)
754 		goto err_out;
755 
756 	cgu->base = of_iomap(np, 0);
757 	if (!cgu->base) {
758 		pr_err("%s: failed to map CGU registers\n", __func__);
759 		goto err_out_free;
760 	}
761 
762 	cgu->np = np;
763 	cgu->clock_info = clock_info;
764 	cgu->clocks.clk_num = num_clocks;
765 
766 	spin_lock_init(&cgu->lock);
767 
768 	return cgu;
769 
770 err_out_free:
771 	kfree(cgu);
772 err_out:
773 	return NULL;
774 }
775 
ingenic_cgu_register_clocks(struct ingenic_cgu * cgu)776 int ingenic_cgu_register_clocks(struct ingenic_cgu *cgu)
777 {
778 	unsigned i;
779 	int err;
780 
781 	cgu->clocks.clks = kcalloc(cgu->clocks.clk_num, sizeof(struct clk *),
782 				   GFP_KERNEL);
783 	if (!cgu->clocks.clks) {
784 		err = -ENOMEM;
785 		goto err_out;
786 	}
787 
788 	for (i = 0; i < cgu->clocks.clk_num; i++) {
789 		err = ingenic_register_clock(cgu, i);
790 		if (err)
791 			goto err_out_unregister;
792 	}
793 
794 	err = of_clk_add_provider(cgu->np, of_clk_src_onecell_get,
795 				  &cgu->clocks);
796 	if (err)
797 		goto err_out_unregister;
798 
799 	return 0;
800 
801 err_out_unregister:
802 	for (i = 0; i < cgu->clocks.clk_num; i++) {
803 		if (!cgu->clocks.clks[i])
804 			continue;
805 		if (cgu->clock_info[i].type & CGU_CLK_EXT)
806 			clk_put(cgu->clocks.clks[i]);
807 		else
808 			clk_unregister(cgu->clocks.clks[i]);
809 	}
810 	kfree(cgu->clocks.clks);
811 err_out:
812 	return err;
813 }
814