clk: Change clk_ops->determine_rate to return a clk_hw as the best parent
[deliverable/linux.git] / drivers / clk / mmp / clk-mix.c
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1/*
2 * mmp mix(div and mux) clock operation source file
3 *
4 * Copyright (C) 2014 Marvell
5 * Chao Xie <chao.xie@marvell.com>
6 *
7 * This file is licensed under the terms of the GNU General Public
8 * License version 2. This program is licensed "as is" without any
9 * warranty of any kind, whether express or implied.
10 */
11
12#include <linux/clk-provider.h>
13#include <linux/slab.h>
14#include <linux/io.h>
15#include <linux/err.h>
16
17#include "clk.h"
18
19/*
20 * The mix clock is a clock combined mux and div type clock.
21 * Because the div field and mux field need to be set at same
22 * time, we can not divide it into 2 types of clock
23 */
24
25#define to_clk_mix(hw) container_of(hw, struct mmp_clk_mix, hw)
26
27static unsigned int _get_maxdiv(struct mmp_clk_mix *mix)
28{
29 unsigned int div_mask = (1 << mix->reg_info.width_div) - 1;
30 unsigned int maxdiv = 0;
31 struct clk_div_table *clkt;
32
33 if (mix->div_flags & CLK_DIVIDER_ONE_BASED)
34 return div_mask;
35 if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO)
36 return 1 << div_mask;
37 if (mix->div_table) {
38 for (clkt = mix->div_table; clkt->div; clkt++)
39 if (clkt->div > maxdiv)
40 maxdiv = clkt->div;
41 return maxdiv;
42 }
43 return div_mask + 1;
44}
45
46static unsigned int _get_div(struct mmp_clk_mix *mix, unsigned int val)
47{
48 struct clk_div_table *clkt;
49
50 if (mix->div_flags & CLK_DIVIDER_ONE_BASED)
51 return val;
52 if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO)
53 return 1 << val;
54 if (mix->div_table) {
55 for (clkt = mix->div_table; clkt->div; clkt++)
56 if (clkt->val == val)
57 return clkt->div;
58 if (clkt->div == 0)
59 return 0;
60 }
61 return val + 1;
62}
63
64static unsigned int _get_mux(struct mmp_clk_mix *mix, unsigned int val)
65{
66 int num_parents = __clk_get_num_parents(mix->hw.clk);
67 int i;
68
69 if (mix->mux_flags & CLK_MUX_INDEX_BIT)
70 return ffs(val) - 1;
71 if (mix->mux_flags & CLK_MUX_INDEX_ONE)
72 return val - 1;
73 if (mix->mux_table) {
74 for (i = 0; i < num_parents; i++)
75 if (mix->mux_table[i] == val)
76 return i;
77 if (i == num_parents)
78 return 0;
79 }
80
81 return val;
82}
83static unsigned int _get_div_val(struct mmp_clk_mix *mix, unsigned int div)
84{
85 struct clk_div_table *clkt;
86
87 if (mix->div_flags & CLK_DIVIDER_ONE_BASED)
88 return div;
89 if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO)
90 return __ffs(div);
91 if (mix->div_table) {
92 for (clkt = mix->div_table; clkt->div; clkt++)
93 if (clkt->div == div)
94 return clkt->val;
95 if (clkt->div == 0)
96 return 0;
97 }
98
99 return div - 1;
100}
101
102static unsigned int _get_mux_val(struct mmp_clk_mix *mix, unsigned int mux)
103{
104 if (mix->mux_table)
105 return mix->mux_table[mux];
106
107 return mux;
108}
109
110static void _filter_clk_table(struct mmp_clk_mix *mix,
111 struct mmp_clk_mix_clk_table *table,
112 unsigned int table_size)
113{
114 int i;
115 struct mmp_clk_mix_clk_table *item;
116 struct clk *parent, *clk;
117 unsigned long parent_rate;
118
119 clk = mix->hw.clk;
120
121 for (i = 0; i < table_size; i++) {
122 item = &table[i];
123 parent = clk_get_parent_by_index(clk, item->parent_index);
124 parent_rate = __clk_get_rate(parent);
125 if (parent_rate % item->rate) {
126 item->valid = 0;
127 } else {
128 item->divisor = parent_rate / item->rate;
129 item->valid = 1;
130 }
131 }
132}
133
134static int _set_rate(struct mmp_clk_mix *mix, u32 mux_val, u32 div_val,
135 unsigned int change_mux, unsigned int change_div)
136{
137 struct mmp_clk_mix_reg_info *ri = &mix->reg_info;
138 u8 width, shift;
139 u32 mux_div, fc_req;
140 int ret, timeout = 50;
141 unsigned long flags = 0;
142
143 if (!change_mux && !change_div)
144 return -EINVAL;
145
146 if (mix->lock)
147 spin_lock_irqsave(mix->lock, flags);
148
149 if (mix->type == MMP_CLK_MIX_TYPE_V1
150 || mix->type == MMP_CLK_MIX_TYPE_V2)
151 mux_div = readl(ri->reg_clk_ctrl);
152 else
153 mux_div = readl(ri->reg_clk_sel);
154
155 if (change_div) {
156 width = ri->width_div;
157 shift = ri->shift_div;
158 mux_div &= ~MMP_CLK_BITS_MASK(width, shift);
159 mux_div |= MMP_CLK_BITS_SET_VAL(div_val, width, shift);
160 }
161
162 if (change_mux) {
163 width = ri->width_mux;
164 shift = ri->shift_mux;
165 mux_div &= ~MMP_CLK_BITS_MASK(width, shift);
166 mux_div |= MMP_CLK_BITS_SET_VAL(mux_val, width, shift);
167 }
168
169 if (mix->type == MMP_CLK_MIX_TYPE_V1) {
170 writel(mux_div, ri->reg_clk_ctrl);
171 } else if (mix->type == MMP_CLK_MIX_TYPE_V2) {
172 mux_div |= (1 << ri->bit_fc);
173 writel(mux_div, ri->reg_clk_ctrl);
174
175 do {
176 fc_req = readl(ri->reg_clk_ctrl);
177 timeout--;
178 if (!(fc_req & (1 << ri->bit_fc)))
179 break;
180 } while (timeout);
181
182 if (timeout == 0) {
183 pr_err("%s:%s cannot do frequency change\n",
184 __func__, __clk_get_name(mix->hw.clk));
185 ret = -EBUSY;
186 goto error;
187 }
188 } else {
189 fc_req = readl(ri->reg_clk_ctrl);
190 fc_req |= 1 << ri->bit_fc;
191 writel(fc_req, ri->reg_clk_ctrl);
192 writel(mux_div, ri->reg_clk_sel);
193 fc_req &= ~(1 << ri->bit_fc);
194 }
195
196 ret = 0;
197error:
198 if (mix->lock)
199 spin_unlock_irqrestore(mix->lock, flags);
200
201 return ret;
202}
203
204static long mmp_clk_mix_determine_rate(struct clk_hw *hw, unsigned long rate,
205 unsigned long *best_parent_rate,
646cafc6 206 struct clk_hw **best_parent_clk)
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207{
208 struct mmp_clk_mix *mix = to_clk_mix(hw);
209 struct mmp_clk_mix_clk_table *item;
210 struct clk *parent, *parent_best, *mix_clk;
211 unsigned long parent_rate, mix_rate, mix_rate_best, parent_rate_best;
212 unsigned long gap, gap_best;
213 u32 div_val_max;
214 unsigned int div;
215 int i, j;
216
217 mix_clk = hw->clk;
218
219 parent = NULL;
220 mix_rate_best = 0;
221 parent_rate_best = 0;
222 gap_best = rate;
223 parent_best = NULL;
224
225 if (mix->table) {
226 for (i = 0; i < mix->table_size; i++) {
227 item = &mix->table[i];
228 if (item->valid == 0)
229 continue;
230 parent = clk_get_parent_by_index(mix_clk,
231 item->parent_index);
232 parent_rate = __clk_get_rate(parent);
233 mix_rate = parent_rate / item->divisor;
234 gap = abs(mix_rate - rate);
235 if (parent_best == NULL || gap < gap_best) {
236 parent_best = parent;
237 parent_rate_best = parent_rate;
238 mix_rate_best = mix_rate;
239 gap_best = gap;
240 if (gap_best == 0)
241 goto found;
242 }
243 }
244 } else {
245 for (i = 0; i < __clk_get_num_parents(mix_clk); i++) {
246 parent = clk_get_parent_by_index(mix_clk, i);
247 parent_rate = __clk_get_rate(parent);
248 div_val_max = _get_maxdiv(mix);
249 for (j = 0; j < div_val_max; j++) {
250 div = _get_div(mix, j);
251 mix_rate = parent_rate / div;
252 gap = abs(mix_rate - rate);
253 if (parent_best == NULL || gap < gap_best) {
254 parent_best = parent;
255 parent_rate_best = parent_rate;
256 mix_rate_best = mix_rate;
257 gap_best = gap;
258 if (gap_best == 0)
259 goto found;
260 }
261 }
262 }
263 }
264
265found:
266 *best_parent_rate = parent_rate_best;
646cafc6 267 *best_parent_clk = __clk_get_hw(parent_best);
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268
269 return mix_rate_best;
270}
271
272static int mmp_clk_mix_set_rate_and_parent(struct clk_hw *hw,
273 unsigned long rate,
274 unsigned long parent_rate,
275 u8 index)
276{
277 struct mmp_clk_mix *mix = to_clk_mix(hw);
278 unsigned int div;
279 u32 div_val, mux_val;
280
281 div = parent_rate / rate;
282 div_val = _get_div_val(mix, div);
283 mux_val = _get_mux_val(mix, index);
284
285 return _set_rate(mix, mux_val, div_val, 1, 1);
286}
287
288static u8 mmp_clk_mix_get_parent(struct clk_hw *hw)
289{
290 struct mmp_clk_mix *mix = to_clk_mix(hw);
291 struct mmp_clk_mix_reg_info *ri = &mix->reg_info;
292 unsigned long flags = 0;
293 u32 mux_div = 0;
294 u8 width, shift;
295 u32 mux_val;
296
297 if (mix->lock)
298 spin_lock_irqsave(mix->lock, flags);
299
300 if (mix->type == MMP_CLK_MIX_TYPE_V1
301 || mix->type == MMP_CLK_MIX_TYPE_V2)
302 mux_div = readl(ri->reg_clk_ctrl);
303 else
304 mux_div = readl(ri->reg_clk_sel);
305
306 if (mix->lock)
307 spin_unlock_irqrestore(mix->lock, flags);
308
309 width = mix->reg_info.width_mux;
310 shift = mix->reg_info.shift_mux;
311
312 mux_val = MMP_CLK_BITS_GET_VAL(mux_div, width, shift);
313
314 return _get_mux(mix, mux_val);
315}
316
317static unsigned long mmp_clk_mix_recalc_rate(struct clk_hw *hw,
318 unsigned long parent_rate)
319{
320 struct mmp_clk_mix *mix = to_clk_mix(hw);
321 struct mmp_clk_mix_reg_info *ri = &mix->reg_info;
322 unsigned long flags = 0;
323 u32 mux_div = 0;
324 u8 width, shift;
325 unsigned int div;
326
327 if (mix->lock)
328 spin_lock_irqsave(mix->lock, flags);
329
330 if (mix->type == MMP_CLK_MIX_TYPE_V1
331 || mix->type == MMP_CLK_MIX_TYPE_V2)
332 mux_div = readl(ri->reg_clk_ctrl);
333 else
334 mux_div = readl(ri->reg_clk_sel);
335
336 if (mix->lock)
337 spin_unlock_irqrestore(mix->lock, flags);
338
339 width = mix->reg_info.width_div;
340 shift = mix->reg_info.shift_div;
341
342 div = _get_div(mix, MMP_CLK_BITS_GET_VAL(mux_div, width, shift));
343
344 return parent_rate / div;
345}
346
347static int mmp_clk_set_parent(struct clk_hw *hw, u8 index)
348{
349 struct mmp_clk_mix *mix = to_clk_mix(hw);
350 struct mmp_clk_mix_clk_table *item;
351 int i;
352 u32 div_val, mux_val;
353
354 if (mix->table) {
355 for (i = 0; i < mix->table_size; i++) {
356 item = &mix->table[i];
357 if (item->valid == 0)
358 continue;
359 if (item->parent_index == index)
360 break;
361 }
362 if (i < mix->table_size) {
363 div_val = _get_div_val(mix, item->divisor);
364 mux_val = _get_mux_val(mix, item->parent_index);
365 } else
366 return -EINVAL;
367 } else {
368 mux_val = _get_mux_val(mix, index);
369 div_val = 0;
370 }
371
372 return _set_rate(mix, mux_val, div_val, 1, div_val ? 1 : 0);
373}
374
375static int mmp_clk_set_rate(struct clk_hw *hw, unsigned long rate,
376 unsigned long best_parent_rate)
377{
378 struct mmp_clk_mix *mix = to_clk_mix(hw);
379 struct mmp_clk_mix_clk_table *item;
380 unsigned long parent_rate;
381 unsigned int best_divisor;
382 struct clk *mix_clk, *parent;
383 int i;
384
385 best_divisor = best_parent_rate / rate;
386
387 mix_clk = hw->clk;
388 if (mix->table) {
389 for (i = 0; i < mix->table_size; i++) {
390 item = &mix->table[i];
391 if (item->valid == 0)
392 continue;
393 parent = clk_get_parent_by_index(mix_clk,
394 item->parent_index);
395 parent_rate = __clk_get_rate(parent);
396 if (parent_rate == best_parent_rate
397 && item->divisor == best_divisor)
398 break;
399 }
400 if (i < mix->table_size)
401 return _set_rate(mix,
402 _get_mux_val(mix, item->parent_index),
403 _get_div_val(mix, item->divisor),
404 1, 1);
405 else
406 return -EINVAL;
407 } else {
408 for (i = 0; i < __clk_get_num_parents(mix_clk); i++) {
409 parent = clk_get_parent_by_index(mix_clk, i);
410 parent_rate = __clk_get_rate(parent);
411 if (parent_rate == best_parent_rate)
412 break;
413 }
414 if (i < __clk_get_num_parents(mix_clk))
415 return _set_rate(mix, _get_mux_val(mix, i),
416 _get_div_val(mix, best_divisor), 1, 1);
417 else
418 return -EINVAL;
419 }
420}
421
422static void mmp_clk_mix_init(struct clk_hw *hw)
423{
424 struct mmp_clk_mix *mix = to_clk_mix(hw);
425
426 if (mix->table)
427 _filter_clk_table(mix, mix->table, mix->table_size);
428}
429
430const struct clk_ops mmp_clk_mix_ops = {
431 .determine_rate = mmp_clk_mix_determine_rate,
432 .set_rate_and_parent = mmp_clk_mix_set_rate_and_parent,
433 .set_rate = mmp_clk_set_rate,
434 .set_parent = mmp_clk_set_parent,
435 .get_parent = mmp_clk_mix_get_parent,
436 .recalc_rate = mmp_clk_mix_recalc_rate,
437 .init = mmp_clk_mix_init,
438};
439
440struct clk *mmp_clk_register_mix(struct device *dev,
441 const char *name,
442 const char **parent_names,
443 u8 num_parents,
444 unsigned long flags,
445 struct mmp_clk_mix_config *config,
446 spinlock_t *lock)
447{
448 struct mmp_clk_mix *mix;
449 struct clk *clk;
450 struct clk_init_data init;
451 size_t table_bytes;
452
453 mix = kzalloc(sizeof(*mix), GFP_KERNEL);
454 if (!mix) {
455 pr_err("%s:%s: could not allocate mmp mix clk\n",
456 __func__, name);
457 return ERR_PTR(-ENOMEM);
458 }
459
460 init.name = name;
461 init.flags = flags | CLK_GET_RATE_NOCACHE;
462 init.parent_names = parent_names;
463 init.num_parents = num_parents;
464 init.ops = &mmp_clk_mix_ops;
465
466 memcpy(&mix->reg_info, &config->reg_info, sizeof(config->reg_info));
467 if (config->table) {
468 table_bytes = sizeof(*config->table) * config->table_size;
469 mix->table = kzalloc(table_bytes, GFP_KERNEL);
470 if (!mix->table) {
471 pr_err("%s:%s: could not allocate mmp mix table\n",
472 __func__, name);
473 kfree(mix);
474 return ERR_PTR(-ENOMEM);
475 }
476 memcpy(mix->table, config->table, table_bytes);
477 mix->table_size = config->table_size;
478 }
479
480 if (config->mux_table) {
481 table_bytes = sizeof(u32) * num_parents;
482 mix->mux_table = kzalloc(table_bytes, GFP_KERNEL);
483 if (!mix->mux_table) {
484 pr_err("%s:%s: could not allocate mmp mix mux-table\n",
485 __func__, name);
486 kfree(mix->table);
487 kfree(mix);
488 return ERR_PTR(-ENOMEM);
489 }
490 memcpy(mix->mux_table, config->mux_table, table_bytes);
491 }
492
493 mix->div_flags = config->div_flags;
494 mix->mux_flags = config->mux_flags;
495 mix->lock = lock;
496 mix->hw.init = &init;
497
498 if (config->reg_info.bit_fc >= 32)
499 mix->type = MMP_CLK_MIX_TYPE_V1;
500 else if (config->reg_info.reg_clk_sel)
501 mix->type = MMP_CLK_MIX_TYPE_V3;
502 else
503 mix->type = MMP_CLK_MIX_TYPE_V2;
504 clk = clk_register(dev, &mix->hw);
505
506 if (IS_ERR(clk)) {
507 kfree(mix->mux_table);
508 kfree(mix->table);
509 kfree(mix);
510 }
511
512 return clk;
513}
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