1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * mmp mix(div and mux) clock operation source file
4 *
5 * Copyright (C) 2014 Marvell
6 * Chao Xie <chao.xie@marvell.com>
7 */
8
9#include <linux/clk-provider.h>
10#include <linux/slab.h>
11#include <linux/io.h>
12#include <linux/err.h>
13
14#include "clk.h"
15
16/*
17 * The mix clock is a clock combined mux and div type clock.
18 * Because the div field and mux field need to be set at same
19 * time, we can not divide it into 2 types of clock
20 */
21
22#define to_clk_mix(hw)	container_of(hw, struct mmp_clk_mix, hw)
23
24static unsigned int _get_maxdiv(struct mmp_clk_mix *mix)
25{
26	unsigned int div_mask = (1 << mix->reg_info.width_div) - 1;
27	unsigned int maxdiv = 0;
28	struct clk_div_table *clkt;
29
30	if (mix->div_flags & CLK_DIVIDER_ONE_BASED)
31		return div_mask;
32	if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO)
33		return 1 << div_mask;
34	if (mix->div_table) {
35		for (clkt = mix->div_table; clkt->div; clkt++)
36			if (clkt->div > maxdiv)
37				maxdiv = clkt->div;
38		return maxdiv;
39	}
40	return div_mask + 1;
41}
42
43static unsigned int _get_div(struct mmp_clk_mix *mix, unsigned int val)
44{
45	struct clk_div_table *clkt;
46
47	if (mix->div_flags & CLK_DIVIDER_ONE_BASED)
48		return val;
49	if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO)
50		return 1 << val;
51	if (mix->div_table) {
52		for (clkt = mix->div_table; clkt->div; clkt++)
53			if (clkt->val == val)
54				return clkt->div;
55		if (clkt->div == 0)
56			return 0;
57	}
58	return val + 1;
59}
60
61static unsigned int _get_mux(struct mmp_clk_mix *mix, unsigned int val)
62{
63	int num_parents = clk_hw_get_num_parents(&mix->hw);
64	int i;
65
66	if (mix->mux_flags & CLK_MUX_INDEX_BIT)
67		return ffs(val) - 1;
68	if (mix->mux_flags & CLK_MUX_INDEX_ONE)
69		return val - 1;
70	if (mix->mux_table) {
71		for (i = 0; i < num_parents; i++)
72			if (mix->mux_table[i] == val)
73				return i;
74		if (i == num_parents)
75			return 0;
76	}
77
78	return val;
79}
80static unsigned int _get_div_val(struct mmp_clk_mix *mix, unsigned int div)
81{
82	struct clk_div_table *clkt;
83
84	if (mix->div_flags & CLK_DIVIDER_ONE_BASED)
85		return div;
86	if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO)
87		return __ffs(div);
88	if (mix->div_table) {
89		for (clkt = mix->div_table; clkt->div; clkt++)
90			if (clkt->div == div)
91				return clkt->val;
92		if (clkt->div == 0)
93			return 0;
94	}
95
96	return div - 1;
97}
98
99static unsigned int _get_mux_val(struct mmp_clk_mix *mix, unsigned int mux)
100{
101	if (mix->mux_table)
102		return mix->mux_table[mux];
103
104	return mux;
105}
106
107static void _filter_clk_table(struct mmp_clk_mix *mix,
108				struct mmp_clk_mix_clk_table *table,
109				unsigned int table_size)
110{
111	int i;
112	struct mmp_clk_mix_clk_table *item;
113	struct clk_hw *parent, *hw;
114	unsigned long parent_rate;
115
116	hw = &mix->hw;
117
118	for (i = 0; i < table_size; i++) {
119		item = &table[i];
120		parent = clk_hw_get_parent_by_index(hw, item->parent_index);
121		parent_rate = clk_hw_get_rate(parent);
122		if (parent_rate % item->rate) {
123			item->valid = 0;
124		} else {
125			item->divisor = parent_rate / item->rate;
126			item->valid = 1;
127		}
128	}
129}
130
131static int _set_rate(struct mmp_clk_mix *mix, u32 mux_val, u32 div_val,
132			unsigned int change_mux, unsigned int change_div)
133{
134	struct mmp_clk_mix_reg_info *ri = &mix->reg_info;
135	u8 width, shift;
136	u32 mux_div, fc_req;
137	int ret, timeout = 50;
138	unsigned long flags = 0;
139
140	if (!change_mux && !change_div)
141		return -EINVAL;
142
143	if (mix->lock)
144		spin_lock_irqsave(mix->lock, flags);
145
146	if (mix->type == MMP_CLK_MIX_TYPE_V1
147		|| mix->type == MMP_CLK_MIX_TYPE_V2)
148		mux_div = readl(ri->reg_clk_ctrl);
149	else
150		mux_div = readl(ri->reg_clk_sel);
151
152	if (change_div) {
153		width = ri->width_div;
154		shift = ri->shift_div;
155		mux_div &= ~MMP_CLK_BITS_MASK(width, shift);
156		mux_div |= MMP_CLK_BITS_SET_VAL(div_val, width, shift);
157	}
158
159	if (change_mux) {
160		width = ri->width_mux;
161		shift = ri->shift_mux;
162		mux_div &= ~MMP_CLK_BITS_MASK(width, shift);
163		mux_div |= MMP_CLK_BITS_SET_VAL(mux_val, width, shift);
164	}
165
166	if (mix->type == MMP_CLK_MIX_TYPE_V1) {
167		writel(mux_div, ri->reg_clk_ctrl);
168	} else if (mix->type == MMP_CLK_MIX_TYPE_V2) {
169		mux_div |= (1 << ri->bit_fc);
170		writel(mux_div, ri->reg_clk_ctrl);
171
172		do {
173			fc_req = readl(ri->reg_clk_ctrl);
174			timeout--;
175			if (!(fc_req & (1 << ri->bit_fc)))
176				break;
177		} while (timeout);
178
179		if (timeout == 0) {
180			pr_err("%s:%s cannot do frequency change\n",
181				__func__, clk_hw_get_name(&mix->hw));
182			ret = -EBUSY;
183			goto error;
184		}
185	} else {
186		fc_req = readl(ri->reg_clk_ctrl);
187		fc_req |= 1 << ri->bit_fc;
188		writel(fc_req, ri->reg_clk_ctrl);
189		writel(mux_div, ri->reg_clk_sel);
190		fc_req &= ~(1 << ri->bit_fc);
191	}
192
193	ret = 0;
194error:
195	if (mix->lock)
196		spin_unlock_irqrestore(mix->lock, flags);
197
198	return ret;
199}
200
201static int mmp_clk_mix_determine_rate(struct clk_hw *hw,
202				      struct clk_rate_request *req)
203{
204	struct mmp_clk_mix *mix = to_clk_mix(hw);
205	struct mmp_clk_mix_clk_table *item;
206	struct clk_hw *parent, *parent_best;
207	unsigned long parent_rate, mix_rate, mix_rate_best, parent_rate_best;
208	unsigned long gap, gap_best;
209	u32 div_val_max;
210	unsigned int div;
211	int i, j;
212
213
214	mix_rate_best = 0;
215	parent_rate_best = 0;
216	gap_best = ULONG_MAX;
217	parent_best = NULL;
218
219	if (mix->table) {
220		for (i = 0; i < mix->table_size; i++) {
221			item = &mix->table[i];
222			if (item->valid == 0)
223				continue;
224			parent = clk_hw_get_parent_by_index(hw,
225							item->parent_index);
226			parent_rate = clk_hw_get_rate(parent);
227			mix_rate = parent_rate / item->divisor;
228			gap = abs(mix_rate - req->rate);
229			if (!parent_best || gap < gap_best) {
230				parent_best = parent;
231				parent_rate_best = parent_rate;
232				mix_rate_best = mix_rate;
233				gap_best = gap;
234				if (gap_best == 0)
235					goto found;
236			}
237		}
238	} else {
239		for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
240			parent = clk_hw_get_parent_by_index(hw, i);
241			parent_rate = clk_hw_get_rate(parent);
242			div_val_max = _get_maxdiv(mix);
243			for (j = 0; j < div_val_max; j++) {
244				div = _get_div(mix, j);
245				mix_rate = parent_rate / div;
246				gap = abs(mix_rate - req->rate);
247				if (!parent_best || gap < gap_best) {
248					parent_best = parent;
249					parent_rate_best = parent_rate;
250					mix_rate_best = mix_rate;
251					gap_best = gap;
252					if (gap_best == 0)
253						goto found;
254				}
255			}
256		}
257	}
258
259found:
260	if (!parent_best)
261		return -EINVAL;
262
263	req->best_parent_rate = parent_rate_best;
264	req->best_parent_hw = parent_best;
265	req->rate = mix_rate_best;
266
267	return 0;
268}
269
270static int mmp_clk_mix_set_rate_and_parent(struct clk_hw *hw,
271						unsigned long rate,
272						unsigned long parent_rate,
273						u8 index)
274{
275	struct mmp_clk_mix *mix = to_clk_mix(hw);
276	unsigned int div;
277	u32 div_val, mux_val;
278
279	div = parent_rate / rate;
280	div_val = _get_div_val(mix, div);
281	mux_val = _get_mux_val(mix, index);
282
283	return _set_rate(mix, mux_val, div_val, 1, 1);
284}
285
286static u8 mmp_clk_mix_get_parent(struct clk_hw *hw)
287{
288	struct mmp_clk_mix *mix = to_clk_mix(hw);
289	struct mmp_clk_mix_reg_info *ri = &mix->reg_info;
290	unsigned long flags = 0;
291	u32 mux_div = 0;
292	u8 width, shift;
293	u32 mux_val;
294
295	if (mix->lock)
296		spin_lock_irqsave(mix->lock, flags);
297
298	if (mix->type == MMP_CLK_MIX_TYPE_V1
299		|| mix->type == MMP_CLK_MIX_TYPE_V2)
300		mux_div = readl(ri->reg_clk_ctrl);
301	else
302		mux_div = readl(ri->reg_clk_sel);
303
304	if (mix->lock)
305		spin_unlock_irqrestore(mix->lock, flags);
306
307	width = mix->reg_info.width_mux;
308	shift = mix->reg_info.shift_mux;
309
310	mux_val = MMP_CLK_BITS_GET_VAL(mux_div, width, shift);
311
312	return _get_mux(mix, mux_val);
313}
314
315static unsigned long mmp_clk_mix_recalc_rate(struct clk_hw *hw,
316					unsigned long parent_rate)
317{
318	struct mmp_clk_mix *mix = to_clk_mix(hw);
319	struct mmp_clk_mix_reg_info *ri = &mix->reg_info;
320	unsigned long flags = 0;
321	u32 mux_div = 0;
322	u8 width, shift;
323	unsigned int div;
324
325	if (mix->lock)
326		spin_lock_irqsave(mix->lock, flags);
327
328	if (mix->type == MMP_CLK_MIX_TYPE_V1
329		|| mix->type == MMP_CLK_MIX_TYPE_V2)
330		mux_div = readl(ri->reg_clk_ctrl);
331	else
332		mux_div = readl(ri->reg_clk_sel);
333
334	if (mix->lock)
335		spin_unlock_irqrestore(mix->lock, flags);
336
337	width = mix->reg_info.width_div;
338	shift = mix->reg_info.shift_div;
339
340	div = _get_div(mix, MMP_CLK_BITS_GET_VAL(mux_div, width, shift));
341
342	return parent_rate / div;
343}
344
345static int mmp_clk_set_parent(struct clk_hw *hw, u8 index)
346{
347	struct mmp_clk_mix *mix = to_clk_mix(hw);
348	struct mmp_clk_mix_clk_table *item;
349	int i;
350	u32 div_val, mux_val;
351
352	if (mix->table) {
353		for (i = 0; i < mix->table_size; i++) {
354			item = &mix->table[i];
355			if (item->valid == 0)
356				continue;
357			if (item->parent_index == index)
358				break;
359		}
360		if (i < mix->table_size) {
361			div_val = _get_div_val(mix, item->divisor);
362			mux_val = _get_mux_val(mix, item->parent_index);
363		} else
364			return -EINVAL;
365	} else {
366		mux_val = _get_mux_val(mix, index);
367		div_val = 0;
368	}
369
370	return _set_rate(mix, mux_val, div_val, 1, div_val ? 1 : 0);
371}
372
373static int mmp_clk_set_rate(struct clk_hw *hw, unsigned long rate,
374				unsigned long best_parent_rate)
375{
376	struct mmp_clk_mix *mix = to_clk_mix(hw);
377	struct mmp_clk_mix_clk_table *item;
378	unsigned long parent_rate;
379	unsigned int best_divisor;
380	struct clk_hw *parent;
381	int i;
382
383	best_divisor = best_parent_rate / rate;
384
385	if (mix->table) {
386		for (i = 0; i < mix->table_size; i++) {
387			item = &mix->table[i];
388			if (item->valid == 0)
389				continue;
390			parent = clk_hw_get_parent_by_index(hw,
391							item->parent_index);
392			parent_rate = clk_hw_get_rate(parent);
393			if (parent_rate == best_parent_rate
394				&& item->divisor == best_divisor)
395				break;
396		}
397		if (i < mix->table_size)
398			return _set_rate(mix,
399					_get_mux_val(mix, item->parent_index),
400					_get_div_val(mix, item->divisor),
401					1, 1);
402		else
403			return -EINVAL;
404	} else {
405		for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
406			parent = clk_hw_get_parent_by_index(hw, i);
407			parent_rate = clk_hw_get_rate(parent);
408			if (parent_rate == best_parent_rate)
409				break;
410		}
411		if (i < clk_hw_get_num_parents(hw))
412			return _set_rate(mix, _get_mux_val(mix, i),
413					_get_div_val(mix, best_divisor), 1, 1);
414		else
415			return -EINVAL;
416	}
417}
418
419static int mmp_clk_mix_init(struct clk_hw *hw)
420{
421	struct mmp_clk_mix *mix = to_clk_mix(hw);
422
423	if (mix->table)
424		_filter_clk_table(mix, mix->table, mix->table_size);
425
426	return 0;
427}
428
429const struct clk_ops mmp_clk_mix_ops = {
430	.determine_rate = mmp_clk_mix_determine_rate,
431	.set_rate_and_parent = mmp_clk_mix_set_rate_and_parent,
432	.set_rate = mmp_clk_set_rate,
433	.set_parent = mmp_clk_set_parent,
434	.get_parent = mmp_clk_mix_get_parent,
435	.recalc_rate = mmp_clk_mix_recalc_rate,
436	.init = mmp_clk_mix_init,
437};
438
439struct clk *mmp_clk_register_mix(struct device *dev,
440					const char *name,
441					const char * const *parent_names,
442					u8 num_parents,
443					unsigned long flags,
444					struct mmp_clk_mix_config *config,
445					spinlock_t *lock)
446{
447	struct mmp_clk_mix *mix;
448	struct clk *clk;
449	struct clk_init_data init;
450	size_t table_bytes;
451
452	mix = kzalloc(sizeof(*mix), GFP_KERNEL);
453	if (!mix)
454		return ERR_PTR(-ENOMEM);
455
456	init.name = name;
457	init.flags = flags | CLK_GET_RATE_NOCACHE;
458	init.parent_names = parent_names;
459	init.num_parents = num_parents;
460	init.ops = &mmp_clk_mix_ops;
461
462	memcpy(&mix->reg_info, &config->reg_info, sizeof(config->reg_info));
463	if (config->table) {
464		table_bytes = sizeof(*config->table) * config->table_size;
465		mix->table = kmemdup(config->table, table_bytes, GFP_KERNEL);
466		if (!mix->table)
467			goto free_mix;
468
469		mix->table_size = config->table_size;
470	}
471
472	if (config->mux_table) {
473		table_bytes = sizeof(u32) * num_parents;
474		mix->mux_table = kmemdup(config->mux_table, table_bytes,
475					 GFP_KERNEL);
476		if (!mix->mux_table) {
477			kfree(mix->table);
478			goto free_mix;
479		}
480	}
481
482	mix->div_flags = config->div_flags;
483	mix->mux_flags = config->mux_flags;
484	mix->lock = lock;
485	mix->hw.init = &init;
486
487	if (config->reg_info.bit_fc >= 32)
488		mix->type = MMP_CLK_MIX_TYPE_V1;
489	else if (config->reg_info.reg_clk_sel)
490		mix->type = MMP_CLK_MIX_TYPE_V3;
491	else
492		mix->type = MMP_CLK_MIX_TYPE_V2;
493	clk = clk_register(dev, &mix->hw);
494
495	if (IS_ERR(clk)) {
496		kfree(mix->mux_table);
497		kfree(mix->table);
498		kfree(mix);
499	}
500
501	return clk;
502
503free_mix:
504	kfree(mix);
505	return ERR_PTR(-ENOMEM);
506}
507