GNU Linux-libre 6.1.24-gnu
[releases.git] / drivers / clk / stm32 / clk-stm32-core.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) STMicroelectronics 2022 - All Rights Reserved
4  * Author: Gabriel Fernandez <gabriel.fernandez@foss.st.com> for STMicroelectronics.
5  */
6
7 #include <linux/clk.h>
8 #include <linux/delay.h>
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/io.h>
12 #include <linux/of.h>
13 #include <linux/of_address.h>
14 #include <linux/slab.h>
15 #include <linux/spinlock.h>
16
17 #include "clk-stm32-core.h"
18 #include "reset-stm32.h"
19
20 static DEFINE_SPINLOCK(rlock);
21
22 static int stm32_rcc_clock_init(struct device *dev,
23                                 const struct of_device_id *match,
24                                 void __iomem *base)
25 {
26         const struct stm32_rcc_match_data *data = match->data;
27         struct clk_hw_onecell_data *clk_data = data->hw_clks;
28         struct device_node *np = dev_of_node(dev);
29         struct clk_hw **hws;
30         int n, max_binding;
31
32         max_binding =  data->maxbinding;
33
34         clk_data = devm_kzalloc(dev, struct_size(clk_data, hws, max_binding), GFP_KERNEL);
35         if (!clk_data)
36                 return -ENOMEM;
37
38         clk_data->num = max_binding;
39
40         hws = clk_data->hws;
41
42         for (n = 0; n < max_binding; n++)
43                 hws[n] = ERR_PTR(-ENOENT);
44
45         for (n = 0; n < data->num_clocks; n++) {
46                 const struct clock_config *cfg_clock = &data->tab_clocks[n];
47                 struct clk_hw *hw = ERR_PTR(-ENOENT);
48
49                 if (data->check_security &&
50                     data->check_security(base, cfg_clock))
51                         continue;
52
53                 if (cfg_clock->func)
54                         hw = (*cfg_clock->func)(dev, data, base, &rlock,
55                                                 cfg_clock);
56
57                 if (IS_ERR(hw)) {
58                         dev_err(dev, "Can't register clk %d: %ld\n", n,
59                                 PTR_ERR(hw));
60                         return PTR_ERR(hw);
61                 }
62
63                 if (cfg_clock->id != NO_ID)
64                         hws[cfg_clock->id] = hw;
65         }
66
67         return of_clk_add_hw_provider(np, of_clk_hw_onecell_get, clk_data);
68 }
69
70 int stm32_rcc_init(struct device *dev, const struct of_device_id *match_data,
71                    void __iomem *base)
72 {
73         const struct of_device_id *match;
74         int err;
75
76         match = of_match_node(match_data, dev_of_node(dev));
77         if (!match) {
78                 dev_err(dev, "match data not found\n");
79                 return -ENODEV;
80         }
81
82         /* RCC Reset Configuration */
83         err = stm32_rcc_reset_init(dev, match, base);
84         if (err) {
85                 pr_err("stm32 reset failed to initialize\n");
86                 return err;
87         }
88
89         /* RCC Clock Configuration */
90         err = stm32_rcc_clock_init(dev, match, base);
91         if (err) {
92                 pr_err("stm32 clock failed to initialize\n");
93                 return err;
94         }
95
96         return 0;
97 }
98
99 static u8 stm32_mux_get_parent(void __iomem *base,
100                                struct clk_stm32_clock_data *data,
101                                u16 mux_id)
102 {
103         const struct stm32_mux_cfg *mux = &data->muxes[mux_id];
104         u32 mask = BIT(mux->width) - 1;
105         u32 val;
106
107         val = readl(base + mux->offset) >> mux->shift;
108         val &= mask;
109
110         return val;
111 }
112
113 static int stm32_mux_set_parent(void __iomem *base,
114                                 struct clk_stm32_clock_data *data,
115                                 u16 mux_id, u8 index)
116 {
117         const struct stm32_mux_cfg *mux = &data->muxes[mux_id];
118
119         u32 mask = BIT(mux->width) - 1;
120         u32 reg = readl(base + mux->offset);
121         u32 val = index << mux->shift;
122
123         reg &= ~(mask << mux->shift);
124         reg |= val;
125
126         writel(reg, base + mux->offset);
127
128         return 0;
129 }
130
131 static void stm32_gate_endisable(void __iomem *base,
132                                  struct clk_stm32_clock_data *data,
133                                  u16 gate_id, int enable)
134 {
135         const struct stm32_gate_cfg *gate = &data->gates[gate_id];
136         void __iomem *addr = base + gate->offset;
137
138         if (enable) {
139                 if (data->gate_cpt[gate_id]++ > 0)
140                         return;
141
142                 if (gate->set_clr != 0)
143                         writel(BIT(gate->bit_idx), addr);
144                 else
145                         writel(readl(addr) | BIT(gate->bit_idx), addr);
146         } else {
147                 if (--data->gate_cpt[gate_id] > 0)
148                         return;
149
150                 if (gate->set_clr != 0)
151                         writel(BIT(gate->bit_idx), addr + gate->set_clr);
152                 else
153                         writel(readl(addr) & ~BIT(gate->bit_idx), addr);
154         }
155 }
156
157 static void stm32_gate_disable_unused(void __iomem *base,
158                                       struct clk_stm32_clock_data *data,
159                                       u16 gate_id)
160 {
161         const struct stm32_gate_cfg *gate = &data->gates[gate_id];
162         void __iomem *addr = base + gate->offset;
163
164         if (data->gate_cpt[gate_id] > 0)
165                 return;
166
167         if (gate->set_clr != 0)
168                 writel(BIT(gate->bit_idx), addr + gate->set_clr);
169         else
170                 writel(readl(addr) & ~BIT(gate->bit_idx), addr);
171 }
172
173 static int stm32_gate_is_enabled(void __iomem *base,
174                                  struct clk_stm32_clock_data *data,
175                                  u16 gate_id)
176 {
177         const struct stm32_gate_cfg *gate = &data->gates[gate_id];
178
179         return (readl(base + gate->offset) & BIT(gate->bit_idx)) != 0;
180 }
181
182 static unsigned int _get_table_div(const struct clk_div_table *table,
183                                    unsigned int val)
184 {
185         const struct clk_div_table *clkt;
186
187         for (clkt = table; clkt->div; clkt++)
188                 if (clkt->val == val)
189                         return clkt->div;
190         return 0;
191 }
192
193 static unsigned int _get_div(const struct clk_div_table *table,
194                              unsigned int val, unsigned long flags, u8 width)
195 {
196         if (flags & CLK_DIVIDER_ONE_BASED)
197                 return val;
198         if (flags & CLK_DIVIDER_POWER_OF_TWO)
199                 return 1 << val;
200         if (table)
201                 return _get_table_div(table, val);
202         return val + 1;
203 }
204
205 static unsigned long stm32_divider_get_rate(void __iomem *base,
206                                             struct clk_stm32_clock_data *data,
207                                             u16 div_id,
208                                             unsigned long parent_rate)
209 {
210         const struct stm32_div_cfg *divider = &data->dividers[div_id];
211         unsigned int val;
212         unsigned int div;
213
214         val =  readl(base + divider->offset) >> divider->shift;
215         val &= clk_div_mask(divider->width);
216         div = _get_div(divider->table, val, divider->flags, divider->width);
217
218         if (!div) {
219                 WARN(!(divider->flags & CLK_DIVIDER_ALLOW_ZERO),
220                      "%d: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n",
221                      div_id);
222                 return parent_rate;
223         }
224
225         return DIV_ROUND_UP_ULL((u64)parent_rate, div);
226 }
227
228 static int stm32_divider_set_rate(void __iomem *base,
229                                   struct clk_stm32_clock_data *data,
230                                   u16 div_id, unsigned long rate,
231                                   unsigned long parent_rate)
232 {
233         const struct stm32_div_cfg *divider = &data->dividers[div_id];
234         int value;
235         u32 val;
236
237         value = divider_get_val(rate, parent_rate, divider->table,
238                                 divider->width, divider->flags);
239         if (value < 0)
240                 return value;
241
242         if (divider->flags & CLK_DIVIDER_HIWORD_MASK) {
243                 val = clk_div_mask(divider->width) << (divider->shift + 16);
244         } else {
245                 val = readl(base + divider->offset);
246                 val &= ~(clk_div_mask(divider->width) << divider->shift);
247         }
248
249         val |= (u32)value << divider->shift;
250
251         writel(val, base + divider->offset);
252
253         return 0;
254 }
255
256 static u8 clk_stm32_mux_get_parent(struct clk_hw *hw)
257 {
258         struct clk_stm32_mux *mux = to_clk_stm32_mux(hw);
259
260         return stm32_mux_get_parent(mux->base, mux->clock_data, mux->mux_id);
261 }
262
263 static int clk_stm32_mux_set_parent(struct clk_hw *hw, u8 index)
264 {
265         struct clk_stm32_mux *mux = to_clk_stm32_mux(hw);
266         unsigned long flags = 0;
267
268         spin_lock_irqsave(mux->lock, flags);
269
270         stm32_mux_set_parent(mux->base, mux->clock_data, mux->mux_id, index);
271
272         spin_unlock_irqrestore(mux->lock, flags);
273
274         return 0;
275 }
276
277 const struct clk_ops clk_stm32_mux_ops = {
278         .get_parent     = clk_stm32_mux_get_parent,
279         .set_parent     = clk_stm32_mux_set_parent,
280 };
281
282 static void clk_stm32_gate_endisable(struct clk_hw *hw, int enable)
283 {
284         struct clk_stm32_gate *gate = to_clk_stm32_gate(hw);
285         unsigned long flags = 0;
286
287         spin_lock_irqsave(gate->lock, flags);
288
289         stm32_gate_endisable(gate->base, gate->clock_data, gate->gate_id, enable);
290
291         spin_unlock_irqrestore(gate->lock, flags);
292 }
293
294 static int clk_stm32_gate_enable(struct clk_hw *hw)
295 {
296         clk_stm32_gate_endisable(hw, 1);
297
298         return 0;
299 }
300
301 static void clk_stm32_gate_disable(struct clk_hw *hw)
302 {
303         clk_stm32_gate_endisable(hw, 0);
304 }
305
306 static int clk_stm32_gate_is_enabled(struct clk_hw *hw)
307 {
308         struct clk_stm32_gate *gate = to_clk_stm32_gate(hw);
309
310         return stm32_gate_is_enabled(gate->base, gate->clock_data, gate->gate_id);
311 }
312
313 static void clk_stm32_gate_disable_unused(struct clk_hw *hw)
314 {
315         struct clk_stm32_gate *gate = to_clk_stm32_gate(hw);
316         unsigned long flags = 0;
317
318         spin_lock_irqsave(gate->lock, flags);
319
320         stm32_gate_disable_unused(gate->base, gate->clock_data, gate->gate_id);
321
322         spin_unlock_irqrestore(gate->lock, flags);
323 }
324
325 const struct clk_ops clk_stm32_gate_ops = {
326         .enable         = clk_stm32_gate_enable,
327         .disable        = clk_stm32_gate_disable,
328         .is_enabled     = clk_stm32_gate_is_enabled,
329         .disable_unused = clk_stm32_gate_disable_unused,
330 };
331
332 static int clk_stm32_divider_set_rate(struct clk_hw *hw, unsigned long rate,
333                                       unsigned long parent_rate)
334 {
335         struct clk_stm32_div *div = to_clk_stm32_divider(hw);
336         unsigned long flags = 0;
337         int ret;
338
339         if (div->div_id == NO_STM32_DIV)
340                 return rate;
341
342         spin_lock_irqsave(div->lock, flags);
343
344         ret = stm32_divider_set_rate(div->base, div->clock_data, div->div_id, rate, parent_rate);
345
346         spin_unlock_irqrestore(div->lock, flags);
347
348         return ret;
349 }
350
351 static long clk_stm32_divider_round_rate(struct clk_hw *hw, unsigned long rate,
352                                          unsigned long *prate)
353 {
354         struct clk_stm32_div *div = to_clk_stm32_divider(hw);
355         const struct stm32_div_cfg *divider;
356
357         if (div->div_id == NO_STM32_DIV)
358                 return rate;
359
360         divider = &div->clock_data->dividers[div->div_id];
361
362         /* if read only, just return current value */
363         if (divider->flags & CLK_DIVIDER_READ_ONLY) {
364                 u32 val;
365
366                 val =  readl(div->base + divider->offset) >> divider->shift;
367                 val &= clk_div_mask(divider->width);
368
369                 return divider_ro_round_rate(hw, rate, prate, divider->table,
370                                 divider->width, divider->flags,
371                                 val);
372         }
373
374         return divider_round_rate_parent(hw, clk_hw_get_parent(hw),
375                                          rate, prate, divider->table,
376                                          divider->width, divider->flags);
377 }
378
379 static unsigned long clk_stm32_divider_recalc_rate(struct clk_hw *hw,
380                                                    unsigned long parent_rate)
381 {
382         struct clk_stm32_div *div = to_clk_stm32_divider(hw);
383
384         if (div->div_id == NO_STM32_DIV)
385                 return parent_rate;
386
387         return stm32_divider_get_rate(div->base, div->clock_data, div->div_id, parent_rate);
388 }
389
390 const struct clk_ops clk_stm32_divider_ops = {
391         .recalc_rate    = clk_stm32_divider_recalc_rate,
392         .round_rate     = clk_stm32_divider_round_rate,
393         .set_rate       = clk_stm32_divider_set_rate,
394 };
395
396 static int clk_stm32_composite_set_rate(struct clk_hw *hw, unsigned long rate,
397                                         unsigned long parent_rate)
398 {
399         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
400         unsigned long flags = 0;
401         int ret;
402
403         if (composite->div_id == NO_STM32_DIV)
404                 return rate;
405
406         spin_lock_irqsave(composite->lock, flags);
407
408         ret = stm32_divider_set_rate(composite->base, composite->clock_data,
409                                      composite->div_id, rate, parent_rate);
410
411         spin_unlock_irqrestore(composite->lock, flags);
412
413         return ret;
414 }
415
416 static unsigned long clk_stm32_composite_recalc_rate(struct clk_hw *hw,
417                                                      unsigned long parent_rate)
418 {
419         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
420
421         if (composite->div_id == NO_STM32_DIV)
422                 return parent_rate;
423
424         return stm32_divider_get_rate(composite->base, composite->clock_data,
425                                       composite->div_id, parent_rate);
426 }
427
428 static long clk_stm32_composite_round_rate(struct clk_hw *hw, unsigned long rate,
429                                            unsigned long *prate)
430 {
431         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
432
433         const struct stm32_div_cfg *divider;
434
435         if (composite->div_id == NO_STM32_DIV)
436                 return rate;
437
438         divider = &composite->clock_data->dividers[composite->div_id];
439
440         /* if read only, just return current value */
441         if (divider->flags & CLK_DIVIDER_READ_ONLY) {
442                 u32 val;
443
444                 val =  readl(composite->base + divider->offset) >> divider->shift;
445                 val &= clk_div_mask(divider->width);
446
447                 return divider_ro_round_rate(hw, rate, prate, divider->table,
448                                 divider->width, divider->flags,
449                                 val);
450         }
451
452         return divider_round_rate_parent(hw, clk_hw_get_parent(hw),
453                                          rate, prate, divider->table,
454                                          divider->width, divider->flags);
455 }
456
457 static u8 clk_stm32_composite_get_parent(struct clk_hw *hw)
458 {
459         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
460
461         return stm32_mux_get_parent(composite->base, composite->clock_data, composite->mux_id);
462 }
463
464 static int clk_stm32_composite_set_parent(struct clk_hw *hw, u8 index)
465 {
466         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
467         unsigned long flags = 0;
468
469         spin_lock_irqsave(composite->lock, flags);
470
471         stm32_mux_set_parent(composite->base, composite->clock_data, composite->mux_id, index);
472
473         spin_unlock_irqrestore(composite->lock, flags);
474
475         if (composite->clock_data->is_multi_mux) {
476                 struct clk_hw *other_mux_hw = composite->clock_data->is_multi_mux(hw);
477
478                 if (other_mux_hw) {
479                         struct clk_hw *hwp = clk_hw_get_parent_by_index(hw, index);
480
481                         clk_hw_reparent(other_mux_hw, hwp);
482                 }
483         }
484
485         return 0;
486 }
487
488 static int clk_stm32_composite_is_enabled(struct clk_hw *hw)
489 {
490         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
491
492         if (composite->gate_id == NO_STM32_GATE)
493                 return (__clk_get_enable_count(hw->clk) > 0);
494
495         return stm32_gate_is_enabled(composite->base, composite->clock_data, composite->gate_id);
496 }
497
498 #define MUX_SAFE_POSITION 0
499
500 static int clk_stm32_has_safe_mux(struct clk_hw *hw)
501 {
502         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
503         const struct stm32_mux_cfg *mux = &composite->clock_data->muxes[composite->mux_id];
504
505         return !!(mux->flags & MUX_SAFE);
506 }
507
508 static void clk_stm32_set_safe_position_mux(struct clk_hw *hw)
509 {
510         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
511
512         if (!clk_stm32_composite_is_enabled(hw)) {
513                 unsigned long flags = 0;
514
515                 if (composite->clock_data->is_multi_mux) {
516                         struct clk_hw *other_mux_hw = NULL;
517
518                         other_mux_hw = composite->clock_data->is_multi_mux(hw);
519
520                         if (!other_mux_hw || clk_stm32_composite_is_enabled(other_mux_hw))
521                                 return;
522                 }
523
524                 spin_lock_irqsave(composite->lock, flags);
525
526                 stm32_mux_set_parent(composite->base, composite->clock_data,
527                                      composite->mux_id, MUX_SAFE_POSITION);
528
529                 spin_unlock_irqrestore(composite->lock, flags);
530         }
531 }
532
533 static void clk_stm32_safe_restore_position_mux(struct clk_hw *hw)
534 {
535         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
536         int sel = clk_hw_get_parent_index(hw);
537         unsigned long flags = 0;
538
539         spin_lock_irqsave(composite->lock, flags);
540
541         stm32_mux_set_parent(composite->base, composite->clock_data, composite->mux_id, sel);
542
543         spin_unlock_irqrestore(composite->lock, flags);
544 }
545
546 static void clk_stm32_composite_gate_endisable(struct clk_hw *hw, int enable)
547 {
548         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
549         unsigned long flags = 0;
550
551         spin_lock_irqsave(composite->lock, flags);
552
553         stm32_gate_endisable(composite->base, composite->clock_data, composite->gate_id, enable);
554
555         spin_unlock_irqrestore(composite->lock, flags);
556 }
557
558 static int clk_stm32_composite_gate_enable(struct clk_hw *hw)
559 {
560         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
561
562         if (composite->gate_id == NO_STM32_GATE)
563                 return 0;
564
565         clk_stm32_composite_gate_endisable(hw, 1);
566
567         if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw))
568                 clk_stm32_safe_restore_position_mux(hw);
569
570         return 0;
571 }
572
573 static void clk_stm32_composite_gate_disable(struct clk_hw *hw)
574 {
575         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
576
577         if (composite->gate_id == NO_STM32_GATE)
578                 return;
579
580         clk_stm32_composite_gate_endisable(hw, 0);
581
582         if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw))
583                 clk_stm32_set_safe_position_mux(hw);
584 }
585
586 static void clk_stm32_composite_disable_unused(struct clk_hw *hw)
587 {
588         struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
589         unsigned long flags = 0;
590
591         if (composite->gate_id == NO_STM32_GATE)
592                 return;
593
594         spin_lock_irqsave(composite->lock, flags);
595
596         stm32_gate_disable_unused(composite->base, composite->clock_data, composite->gate_id);
597
598         spin_unlock_irqrestore(composite->lock, flags);
599 }
600
601 const struct clk_ops clk_stm32_composite_ops = {
602         .set_rate       = clk_stm32_composite_set_rate,
603         .recalc_rate    = clk_stm32_composite_recalc_rate,
604         .round_rate     = clk_stm32_composite_round_rate,
605         .get_parent     = clk_stm32_composite_get_parent,
606         .set_parent     = clk_stm32_composite_set_parent,
607         .enable         = clk_stm32_composite_gate_enable,
608         .disable        = clk_stm32_composite_gate_disable,
609         .is_enabled     = clk_stm32_composite_is_enabled,
610         .disable_unused = clk_stm32_composite_disable_unused,
611 };
612
613 struct clk_hw *clk_stm32_mux_register(struct device *dev,
614                                       const struct stm32_rcc_match_data *data,
615                                       void __iomem *base,
616                                       spinlock_t *lock,
617                                       const struct clock_config *cfg)
618 {
619         struct clk_stm32_mux *mux = cfg->clock_cfg;
620         struct clk_hw *hw = &mux->hw;
621         int err;
622
623         mux->base = base;
624         mux->lock = lock;
625         mux->clock_data = data->clock_data;
626
627         err = clk_hw_register(dev, hw);
628         if (err)
629                 return ERR_PTR(err);
630
631         return hw;
632 }
633
634 struct clk_hw *clk_stm32_gate_register(struct device *dev,
635                                        const struct stm32_rcc_match_data *data,
636                                        void __iomem *base,
637                                        spinlock_t *lock,
638                                        const struct clock_config *cfg)
639 {
640         struct clk_stm32_gate *gate = cfg->clock_cfg;
641         struct clk_hw *hw = &gate->hw;
642         int err;
643
644         gate->base = base;
645         gate->lock = lock;
646         gate->clock_data = data->clock_data;
647
648         err = clk_hw_register(dev, hw);
649         if (err)
650                 return ERR_PTR(err);
651
652         return hw;
653 }
654
655 struct clk_hw *clk_stm32_div_register(struct device *dev,
656                                       const struct stm32_rcc_match_data *data,
657                                       void __iomem *base,
658                                       spinlock_t *lock,
659                                       const struct clock_config *cfg)
660 {
661         struct clk_stm32_div *div = cfg->clock_cfg;
662         struct clk_hw *hw = &div->hw;
663         int err;
664
665         div->base = base;
666         div->lock = lock;
667         div->clock_data = data->clock_data;
668
669         err = clk_hw_register(dev, hw);
670         if (err)
671                 return ERR_PTR(err);
672
673         return hw;
674 }
675
676 struct clk_hw *clk_stm32_composite_register(struct device *dev,
677                                             const struct stm32_rcc_match_data *data,
678                                             void __iomem *base,
679                                             spinlock_t *lock,
680                                             const struct clock_config *cfg)
681 {
682         struct clk_stm32_composite *composite = cfg->clock_cfg;
683         struct clk_hw *hw = &composite->hw;
684         int err;
685
686         composite->base = base;
687         composite->lock = lock;
688         composite->clock_data = data->clock_data;
689
690         err = clk_hw_register(dev, hw);
691         if (err)
692                 return ERR_PTR(err);
693
694         return hw;
695 }