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
20static DEFINE_SPINLOCK(rlock);
21
22static 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(error: -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(error: -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(ptr: hw)) {
58 dev_err(dev, "Can't register clk %d: %ld\n", n,
59 PTR_ERR(hw));
60 return PTR_ERR(ptr: 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, get: of_clk_hw_onecell_get, data: clk_data);
68}
69
70int stm32_rcc_init(struct device *dev, const struct of_device_id *match_data,
71 void __iomem *base)
72{
73 const struct stm32_rcc_match_data *rcc_match_data;
74 const struct of_device_id *match;
75 int err;
76
77 match = of_match_node(matches: match_data, node: dev_of_node(dev));
78 if (!match) {
79 dev_err(dev, "match data not found\n");
80 return -ENODEV;
81 }
82
83 rcc_match_data = match->data;
84
85 /* RCC Reset Configuration */
86 err = stm32_rcc_reset_init(dev, data: rcc_match_data->reset_data, base);
87 if (err) {
88 pr_err("stm32 reset failed to initialize\n");
89 return err;
90 }
91
92 /* RCC Clock Configuration */
93 err = stm32_rcc_clock_init(dev, match, base);
94 if (err) {
95 pr_err("stm32 clock failed to initialize\n");
96 return err;
97 }
98
99 return 0;
100}
101
102static u8 stm32_mux_get_parent(void __iomem *base,
103 struct clk_stm32_clock_data *data,
104 u16 mux_id)
105{
106 const struct stm32_mux_cfg *mux = &data->muxes[mux_id];
107 u32 mask = BIT(mux->width) - 1;
108 u32 val;
109
110 val = readl(addr: base + mux->offset) >> mux->shift;
111 val &= mask;
112
113 return val;
114}
115
116static int stm32_mux_set_parent(void __iomem *base,
117 struct clk_stm32_clock_data *data,
118 u16 mux_id, u8 index)
119{
120 const struct stm32_mux_cfg *mux = &data->muxes[mux_id];
121
122 u32 mask = BIT(mux->width) - 1;
123 u32 reg = readl(addr: base + mux->offset);
124 u32 val = index << mux->shift;
125
126 reg &= ~(mask << mux->shift);
127 reg |= val;
128
129 writel(val: reg, addr: base + mux->offset);
130
131 return 0;
132}
133
134static void stm32_gate_endisable(void __iomem *base,
135 struct clk_stm32_clock_data *data,
136 u16 gate_id, int enable)
137{
138 const struct stm32_gate_cfg *gate = &data->gates[gate_id];
139 void __iomem *addr = base + gate->offset;
140
141 if (enable) {
142 if (data->gate_cpt[gate_id]++ > 0)
143 return;
144
145 if (gate->set_clr != 0)
146 writel(BIT(gate->bit_idx), addr);
147 else
148 writel(readl(addr) | BIT(gate->bit_idx), addr);
149 } else {
150 if (--data->gate_cpt[gate_id] > 0)
151 return;
152
153 if (gate->set_clr != 0)
154 writel(BIT(gate->bit_idx), addr: addr + gate->set_clr);
155 else
156 writel(readl(addr) & ~BIT(gate->bit_idx), addr);
157 }
158}
159
160static void stm32_gate_disable_unused(void __iomem *base,
161 struct clk_stm32_clock_data *data,
162 u16 gate_id)
163{
164 const struct stm32_gate_cfg *gate = &data->gates[gate_id];
165 void __iomem *addr = base + gate->offset;
166
167 if (data->gate_cpt[gate_id] > 0)
168 return;
169
170 if (gate->set_clr != 0)
171 writel(BIT(gate->bit_idx), addr: addr + gate->set_clr);
172 else
173 writel(readl(addr) & ~BIT(gate->bit_idx), addr);
174}
175
176static int stm32_gate_is_enabled(void __iomem *base,
177 struct clk_stm32_clock_data *data,
178 u16 gate_id)
179{
180 const struct stm32_gate_cfg *gate = &data->gates[gate_id];
181
182 return (readl(addr: base + gate->offset) & BIT(gate->bit_idx)) != 0;
183}
184
185static unsigned int _get_table_div(const struct clk_div_table *table,
186 unsigned int val)
187{
188 const struct clk_div_table *clkt;
189
190 for (clkt = table; clkt->div; clkt++)
191 if (clkt->val == val)
192 return clkt->div;
193 return 0;
194}
195
196static unsigned int _get_div(const struct clk_div_table *table,
197 unsigned int val, unsigned long flags, u8 width)
198{
199 if (flags & CLK_DIVIDER_ONE_BASED)
200 return val;
201 if (flags & CLK_DIVIDER_POWER_OF_TWO)
202 return 1 << val;
203 if (table)
204 return _get_table_div(table, val);
205 return val + 1;
206}
207
208static unsigned long stm32_divider_get_rate(void __iomem *base,
209 struct clk_stm32_clock_data *data,
210 u16 div_id,
211 unsigned long parent_rate)
212{
213 const struct stm32_div_cfg *divider = &data->dividers[div_id];
214 unsigned int val;
215 unsigned int div;
216
217 val = readl(addr: base + divider->offset) >> divider->shift;
218 val &= clk_div_mask(divider->width);
219 div = _get_div(table: divider->table, val, flags: divider->flags, width: divider->width);
220
221 if (!div) {
222 WARN(!(divider->flags & CLK_DIVIDER_ALLOW_ZERO),
223 "%d: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n",
224 div_id);
225 return parent_rate;
226 }
227
228 return DIV_ROUND_UP_ULL((u64)parent_rate, div);
229}
230
231static int stm32_divider_set_rate(void __iomem *base,
232 struct clk_stm32_clock_data *data,
233 u16 div_id, unsigned long rate,
234 unsigned long parent_rate)
235{
236 const struct stm32_div_cfg *divider = &data->dividers[div_id];
237 int value;
238 u32 val;
239
240 value = divider_get_val(rate, parent_rate, table: divider->table,
241 width: divider->width, flags: divider->flags);
242 if (value < 0)
243 return value;
244
245 if (divider->flags & CLK_DIVIDER_HIWORD_MASK) {
246 val = clk_div_mask(divider->width) << (divider->shift + 16);
247 } else {
248 val = readl(addr: base + divider->offset);
249 val &= ~(clk_div_mask(divider->width) << divider->shift);
250 }
251
252 val |= (u32)value << divider->shift;
253
254 writel(val, addr: base + divider->offset);
255
256 return 0;
257}
258
259static u8 clk_stm32_mux_get_parent(struct clk_hw *hw)
260{
261 struct clk_stm32_mux *mux = to_clk_stm32_mux(hw);
262
263 return stm32_mux_get_parent(base: mux->base, data: mux->clock_data, mux_id: mux->mux_id);
264}
265
266static int clk_stm32_mux_set_parent(struct clk_hw *hw, u8 index)
267{
268 struct clk_stm32_mux *mux = to_clk_stm32_mux(hw);
269 unsigned long flags = 0;
270
271 spin_lock_irqsave(mux->lock, flags);
272
273 stm32_mux_set_parent(base: mux->base, data: mux->clock_data, mux_id: mux->mux_id, index);
274
275 spin_unlock_irqrestore(lock: mux->lock, flags);
276
277 return 0;
278}
279
280const struct clk_ops clk_stm32_mux_ops = {
281 .determine_rate = __clk_mux_determine_rate,
282 .get_parent = clk_stm32_mux_get_parent,
283 .set_parent = clk_stm32_mux_set_parent,
284};
285
286static void clk_stm32_gate_endisable(struct clk_hw *hw, int enable)
287{
288 struct clk_stm32_gate *gate = to_clk_stm32_gate(hw);
289 unsigned long flags = 0;
290
291 spin_lock_irqsave(gate->lock, flags);
292
293 stm32_gate_endisable(base: gate->base, data: gate->clock_data, gate_id: gate->gate_id, enable);
294
295 spin_unlock_irqrestore(lock: gate->lock, flags);
296}
297
298static int clk_stm32_gate_enable(struct clk_hw *hw)
299{
300 clk_stm32_gate_endisable(hw, enable: 1);
301
302 return 0;
303}
304
305static void clk_stm32_gate_disable(struct clk_hw *hw)
306{
307 clk_stm32_gate_endisable(hw, enable: 0);
308}
309
310static int clk_stm32_gate_is_enabled(struct clk_hw *hw)
311{
312 struct clk_stm32_gate *gate = to_clk_stm32_gate(hw);
313
314 return stm32_gate_is_enabled(base: gate->base, data: gate->clock_data, gate_id: gate->gate_id);
315}
316
317static void clk_stm32_gate_disable_unused(struct clk_hw *hw)
318{
319 struct clk_stm32_gate *gate = to_clk_stm32_gate(hw);
320 unsigned long flags = 0;
321
322 spin_lock_irqsave(gate->lock, flags);
323
324 stm32_gate_disable_unused(base: gate->base, data: gate->clock_data, gate_id: gate->gate_id);
325
326 spin_unlock_irqrestore(lock: gate->lock, flags);
327}
328
329const struct clk_ops clk_stm32_gate_ops = {
330 .enable = clk_stm32_gate_enable,
331 .disable = clk_stm32_gate_disable,
332 .is_enabled = clk_stm32_gate_is_enabled,
333 .disable_unused = clk_stm32_gate_disable_unused,
334};
335
336static int clk_stm32_divider_set_rate(struct clk_hw *hw, unsigned long rate,
337 unsigned long parent_rate)
338{
339 struct clk_stm32_div *div = to_clk_stm32_divider(hw);
340 unsigned long flags = 0;
341 int ret;
342
343 if (div->div_id == NO_STM32_DIV)
344 return rate;
345
346 spin_lock_irqsave(div->lock, flags);
347
348 ret = stm32_divider_set_rate(base: div->base, data: div->clock_data, div_id: div->div_id, rate, parent_rate);
349
350 spin_unlock_irqrestore(lock: div->lock, flags);
351
352 return ret;
353}
354
355static long clk_stm32_divider_round_rate(struct clk_hw *hw, unsigned long rate,
356 unsigned long *prate)
357{
358 struct clk_stm32_div *div = to_clk_stm32_divider(hw);
359 const struct stm32_div_cfg *divider;
360
361 if (div->div_id == NO_STM32_DIV)
362 return rate;
363
364 divider = &div->clock_data->dividers[div->div_id];
365
366 /* if read only, just return current value */
367 if (divider->flags & CLK_DIVIDER_READ_ONLY) {
368 u32 val;
369
370 val = readl(addr: div->base + divider->offset) >> divider->shift;
371 val &= clk_div_mask(divider->width);
372
373 return divider_ro_round_rate(hw, rate, prate, table: divider->table,
374 width: divider->width, flags: divider->flags,
375 val);
376 }
377
378 return divider_round_rate_parent(hw, parent: clk_hw_get_parent(hw),
379 rate, prate, table: divider->table,
380 width: divider->width, flags: divider->flags);
381}
382
383static unsigned long clk_stm32_divider_recalc_rate(struct clk_hw *hw,
384 unsigned long parent_rate)
385{
386 struct clk_stm32_div *div = to_clk_stm32_divider(hw);
387
388 if (div->div_id == NO_STM32_DIV)
389 return parent_rate;
390
391 return stm32_divider_get_rate(base: div->base, data: div->clock_data, div_id: div->div_id, parent_rate);
392}
393
394const struct clk_ops clk_stm32_divider_ops = {
395 .recalc_rate = clk_stm32_divider_recalc_rate,
396 .round_rate = clk_stm32_divider_round_rate,
397 .set_rate = clk_stm32_divider_set_rate,
398};
399
400static int clk_stm32_composite_set_rate(struct clk_hw *hw, unsigned long rate,
401 unsigned long parent_rate)
402{
403 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
404 unsigned long flags = 0;
405 int ret;
406
407 if (composite->div_id == NO_STM32_DIV)
408 return rate;
409
410 spin_lock_irqsave(composite->lock, flags);
411
412 ret = stm32_divider_set_rate(base: composite->base, data: composite->clock_data,
413 div_id: composite->div_id, rate, parent_rate);
414
415 spin_unlock_irqrestore(lock: composite->lock, flags);
416
417 return ret;
418}
419
420static unsigned long clk_stm32_composite_recalc_rate(struct clk_hw *hw,
421 unsigned long parent_rate)
422{
423 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
424
425 if (composite->div_id == NO_STM32_DIV)
426 return parent_rate;
427
428 return stm32_divider_get_rate(base: composite->base, data: composite->clock_data,
429 div_id: composite->div_id, parent_rate);
430}
431
432static int clk_stm32_composite_determine_rate(struct clk_hw *hw,
433 struct clk_rate_request *req)
434{
435 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
436 const struct stm32_div_cfg *divider;
437 long rate;
438
439 if (composite->div_id == NO_STM32_DIV)
440 return 0;
441
442 divider = &composite->clock_data->dividers[composite->div_id];
443
444 /* if read only, just return current value */
445 if (divider->flags & CLK_DIVIDER_READ_ONLY) {
446 u32 val;
447
448 val = readl(addr: composite->base + divider->offset) >> divider->shift;
449 val &= clk_div_mask(divider->width);
450
451 rate = divider_ro_round_rate(hw, rate: req->rate, prate: &req->best_parent_rate,
452 table: divider->table, width: divider->width, flags: divider->flags,
453 val);
454 if (rate < 0)
455 return rate;
456
457 req->rate = rate;
458 return 0;
459 }
460
461 rate = divider_round_rate_parent(hw, parent: clk_hw_get_parent(hw),
462 rate: req->rate, prate: &req->best_parent_rate,
463 table: divider->table, width: divider->width, flags: divider->flags);
464 if (rate < 0)
465 return rate;
466
467 req->rate = rate;
468 return 0;
469}
470
471static u8 clk_stm32_composite_get_parent(struct clk_hw *hw)
472{
473 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
474
475 return stm32_mux_get_parent(base: composite->base, data: composite->clock_data, mux_id: composite->mux_id);
476}
477
478static int clk_stm32_composite_set_parent(struct clk_hw *hw, u8 index)
479{
480 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
481 unsigned long flags = 0;
482
483 spin_lock_irqsave(composite->lock, flags);
484
485 stm32_mux_set_parent(base: composite->base, data: composite->clock_data, mux_id: composite->mux_id, index);
486
487 spin_unlock_irqrestore(lock: composite->lock, flags);
488
489 if (composite->clock_data->is_multi_mux) {
490 struct clk_hw *other_mux_hw = composite->clock_data->is_multi_mux(hw);
491
492 if (other_mux_hw) {
493 struct clk_hw *hwp = clk_hw_get_parent_by_index(hw, index);
494
495 clk_hw_reparent(hw: other_mux_hw, new_parent: hwp);
496 }
497 }
498
499 return 0;
500}
501
502static int clk_stm32_composite_is_enabled(struct clk_hw *hw)
503{
504 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
505
506 if (composite->gate_id == NO_STM32_GATE)
507 return (__clk_get_enable_count(clk: hw->clk) > 0);
508
509 return stm32_gate_is_enabled(base: composite->base, data: composite->clock_data, gate_id: composite->gate_id);
510}
511
512#define MUX_SAFE_POSITION 0
513
514static int clk_stm32_has_safe_mux(struct clk_hw *hw)
515{
516 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
517 const struct stm32_mux_cfg *mux = &composite->clock_data->muxes[composite->mux_id];
518
519 return !!(mux->flags & MUX_SAFE);
520}
521
522static void clk_stm32_set_safe_position_mux(struct clk_hw *hw)
523{
524 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
525
526 if (!clk_stm32_composite_is_enabled(hw)) {
527 unsigned long flags = 0;
528
529 if (composite->clock_data->is_multi_mux) {
530 struct clk_hw *other_mux_hw = NULL;
531
532 other_mux_hw = composite->clock_data->is_multi_mux(hw);
533
534 if (!other_mux_hw || clk_stm32_composite_is_enabled(hw: other_mux_hw))
535 return;
536 }
537
538 spin_lock_irqsave(composite->lock, flags);
539
540 stm32_mux_set_parent(base: composite->base, data: composite->clock_data,
541 mux_id: composite->mux_id, MUX_SAFE_POSITION);
542
543 spin_unlock_irqrestore(lock: composite->lock, flags);
544 }
545}
546
547static void clk_stm32_safe_restore_position_mux(struct clk_hw *hw)
548{
549 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
550 int sel = clk_hw_get_parent_index(hw);
551 unsigned long flags = 0;
552
553 spin_lock_irqsave(composite->lock, flags);
554
555 stm32_mux_set_parent(base: composite->base, data: composite->clock_data, mux_id: composite->mux_id, index: sel);
556
557 spin_unlock_irqrestore(lock: composite->lock, flags);
558}
559
560static void clk_stm32_composite_gate_endisable(struct clk_hw *hw, int enable)
561{
562 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
563 unsigned long flags = 0;
564
565 spin_lock_irqsave(composite->lock, flags);
566
567 stm32_gate_endisable(base: composite->base, data: composite->clock_data, gate_id: composite->gate_id, enable);
568
569 spin_unlock_irqrestore(lock: composite->lock, flags);
570}
571
572static int clk_stm32_composite_gate_enable(struct clk_hw *hw)
573{
574 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
575
576 if (composite->gate_id == NO_STM32_GATE)
577 return 0;
578
579 clk_stm32_composite_gate_endisable(hw, enable: 1);
580
581 if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw))
582 clk_stm32_safe_restore_position_mux(hw);
583
584 return 0;
585}
586
587static void clk_stm32_composite_gate_disable(struct clk_hw *hw)
588{
589 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
590
591 if (composite->gate_id == NO_STM32_GATE)
592 return;
593
594 clk_stm32_composite_gate_endisable(hw, enable: 0);
595
596 if (composite->mux_id != NO_STM32_MUX && clk_stm32_has_safe_mux(hw))
597 clk_stm32_set_safe_position_mux(hw);
598}
599
600static void clk_stm32_composite_disable_unused(struct clk_hw *hw)
601{
602 struct clk_stm32_composite *composite = to_clk_stm32_composite(hw);
603 unsigned long flags = 0;
604
605 if (composite->gate_id == NO_STM32_GATE)
606 return;
607
608 spin_lock_irqsave(composite->lock, flags);
609
610 stm32_gate_disable_unused(base: composite->base, data: composite->clock_data, gate_id: composite->gate_id);
611
612 spin_unlock_irqrestore(lock: composite->lock, flags);
613}
614
615const struct clk_ops clk_stm32_composite_ops = {
616 .set_rate = clk_stm32_composite_set_rate,
617 .recalc_rate = clk_stm32_composite_recalc_rate,
618 .determine_rate = clk_stm32_composite_determine_rate,
619 .get_parent = clk_stm32_composite_get_parent,
620 .set_parent = clk_stm32_composite_set_parent,
621 .enable = clk_stm32_composite_gate_enable,
622 .disable = clk_stm32_composite_gate_disable,
623 .is_enabled = clk_stm32_composite_is_enabled,
624 .disable_unused = clk_stm32_composite_disable_unused,
625};
626
627struct clk_hw *clk_stm32_mux_register(struct device *dev,
628 const struct stm32_rcc_match_data *data,
629 void __iomem *base,
630 spinlock_t *lock,
631 const struct clock_config *cfg)
632{
633 struct clk_stm32_mux *mux = cfg->clock_cfg;
634 struct clk_hw *hw = &mux->hw;
635 int err;
636
637 mux->base = base;
638 mux->lock = lock;
639 mux->clock_data = data->clock_data;
640
641 err = clk_hw_register(dev, hw);
642 if (err)
643 return ERR_PTR(error: err);
644
645 return hw;
646}
647
648struct clk_hw *clk_stm32_gate_register(struct device *dev,
649 const struct stm32_rcc_match_data *data,
650 void __iomem *base,
651 spinlock_t *lock,
652 const struct clock_config *cfg)
653{
654 struct clk_stm32_gate *gate = cfg->clock_cfg;
655 struct clk_hw *hw = &gate->hw;
656 int err;
657
658 gate->base = base;
659 gate->lock = lock;
660 gate->clock_data = data->clock_data;
661
662 err = clk_hw_register(dev, hw);
663 if (err)
664 return ERR_PTR(error: err);
665
666 return hw;
667}
668
669struct clk_hw *clk_stm32_div_register(struct device *dev,
670 const struct stm32_rcc_match_data *data,
671 void __iomem *base,
672 spinlock_t *lock,
673 const struct clock_config *cfg)
674{
675 struct clk_stm32_div *div = cfg->clock_cfg;
676 struct clk_hw *hw = &div->hw;
677 int err;
678
679 div->base = base;
680 div->lock = lock;
681 div->clock_data = data->clock_data;
682
683 err = clk_hw_register(dev, hw);
684 if (err)
685 return ERR_PTR(error: err);
686
687 return hw;
688}
689
690struct clk_hw *clk_stm32_composite_register(struct device *dev,
691 const struct stm32_rcc_match_data *data,
692 void __iomem *base,
693 spinlock_t *lock,
694 const struct clock_config *cfg)
695{
696 struct clk_stm32_composite *composite = cfg->clock_cfg;
697 struct clk_hw *hw = &composite->hw;
698 int err;
699
700 composite->base = base;
701 composite->lock = lock;
702 composite->clock_data = data->clock_data;
703
704 err = clk_hw_register(dev, hw);
705 if (err)
706 return ERR_PTR(error: err);
707
708 return hw;
709}
710

source code of linux/drivers/clk/stm32/clk-stm32-core.c