1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com> |
4 | * Copyright (C) 2011-2012 Linaro Ltd <mturquette@linaro.org> |
5 | * |
6 | * Standard functionality for the common clock API. See Documentation/driver-api/clk.rst |
7 | */ |
8 | |
9 | #include <linux/clk.h> |
10 | #include <linux/clk-provider.h> |
11 | #include <linux/clk/clk-conf.h> |
12 | #include <linux/module.h> |
13 | #include <linux/mutex.h> |
14 | #include <linux/spinlock.h> |
15 | #include <linux/err.h> |
16 | #include <linux/list.h> |
17 | #include <linux/slab.h> |
18 | #include <linux/of.h> |
19 | #include <linux/device.h> |
20 | #include <linux/init.h> |
21 | #include <linux/pm_runtime.h> |
22 | #include <linux/sched.h> |
23 | #include <linux/clkdev.h> |
24 | |
25 | #include "clk.h" |
26 | |
27 | static DEFINE_SPINLOCK(enable_lock); |
28 | static DEFINE_MUTEX(prepare_lock); |
29 | |
30 | static struct task_struct *prepare_owner; |
31 | static struct task_struct *enable_owner; |
32 | |
33 | static int prepare_refcnt; |
34 | static int enable_refcnt; |
35 | |
36 | static HLIST_HEAD(clk_root_list); |
37 | static HLIST_HEAD(clk_orphan_list); |
38 | static LIST_HEAD(clk_notifier_list); |
39 | |
40 | static const struct hlist_head *all_lists[] = { |
41 | &clk_root_list, |
42 | &clk_orphan_list, |
43 | NULL, |
44 | }; |
45 | |
46 | /*** private data structures ***/ |
47 | |
48 | struct clk_parent_map { |
49 | const struct clk_hw *hw; |
50 | struct clk_core *core; |
51 | const char *fw_name; |
52 | const char *name; |
53 | int index; |
54 | }; |
55 | |
56 | struct clk_core { |
57 | const char *name; |
58 | const struct clk_ops *ops; |
59 | struct clk_hw *hw; |
60 | struct module *owner; |
61 | struct device *dev; |
62 | struct device_node *of_node; |
63 | struct clk_core *parent; |
64 | struct clk_parent_map *parents; |
65 | u8 num_parents; |
66 | u8 new_parent_index; |
67 | unsigned long rate; |
68 | unsigned long req_rate; |
69 | unsigned long new_rate; |
70 | struct clk_core *new_parent; |
71 | struct clk_core *new_child; |
72 | unsigned long flags; |
73 | bool orphan; |
74 | bool rpm_enabled; |
75 | unsigned int enable_count; |
76 | unsigned int prepare_count; |
77 | unsigned int protect_count; |
78 | unsigned long min_rate; |
79 | unsigned long max_rate; |
80 | unsigned long accuracy; |
81 | int phase; |
82 | struct clk_duty duty; |
83 | struct hlist_head children; |
84 | struct hlist_node child_node; |
85 | struct hlist_head clks; |
86 | unsigned int notifier_count; |
87 | #ifdef CONFIG_DEBUG_FS |
88 | struct dentry *dentry; |
89 | struct hlist_node debug_node; |
90 | #endif |
91 | struct kref ref; |
92 | }; |
93 | |
94 | #define CREATE_TRACE_POINTS |
95 | #include <trace/events/clk.h> |
96 | |
97 | struct clk { |
98 | struct clk_core *core; |
99 | struct device *dev; |
100 | const char *dev_id; |
101 | const char *con_id; |
102 | unsigned long min_rate; |
103 | unsigned long max_rate; |
104 | unsigned int exclusive_count; |
105 | struct hlist_node clks_node; |
106 | }; |
107 | |
108 | /*** runtime pm ***/ |
109 | static int clk_pm_runtime_get(struct clk_core *core) |
110 | { |
111 | if (!core->rpm_enabled) |
112 | return 0; |
113 | |
114 | return pm_runtime_resume_and_get(dev: core->dev); |
115 | } |
116 | |
117 | static void clk_pm_runtime_put(struct clk_core *core) |
118 | { |
119 | if (!core->rpm_enabled) |
120 | return; |
121 | |
122 | pm_runtime_put_sync(dev: core->dev); |
123 | } |
124 | |
125 | /*** locking ***/ |
126 | static void clk_prepare_lock(void) |
127 | { |
128 | if (!mutex_trylock(lock: &prepare_lock)) { |
129 | if (prepare_owner == current) { |
130 | prepare_refcnt++; |
131 | return; |
132 | } |
133 | mutex_lock(&prepare_lock); |
134 | } |
135 | WARN_ON_ONCE(prepare_owner != NULL); |
136 | WARN_ON_ONCE(prepare_refcnt != 0); |
137 | prepare_owner = current; |
138 | prepare_refcnt = 1; |
139 | } |
140 | |
141 | static void clk_prepare_unlock(void) |
142 | { |
143 | WARN_ON_ONCE(prepare_owner != current); |
144 | WARN_ON_ONCE(prepare_refcnt == 0); |
145 | |
146 | if (--prepare_refcnt) |
147 | return; |
148 | prepare_owner = NULL; |
149 | mutex_unlock(lock: &prepare_lock); |
150 | } |
151 | |
152 | static unsigned long clk_enable_lock(void) |
153 | __acquires(enable_lock) |
154 | { |
155 | unsigned long flags; |
156 | |
157 | /* |
158 | * On UP systems, spin_trylock_irqsave() always returns true, even if |
159 | * we already hold the lock. So, in that case, we rely only on |
160 | * reference counting. |
161 | */ |
162 | if (!IS_ENABLED(CONFIG_SMP) || |
163 | !spin_trylock_irqsave(&enable_lock, flags)) { |
164 | if (enable_owner == current) { |
165 | enable_refcnt++; |
166 | __acquire(enable_lock); |
167 | if (!IS_ENABLED(CONFIG_SMP)) |
168 | local_save_flags(flags); |
169 | return flags; |
170 | } |
171 | spin_lock_irqsave(&enable_lock, flags); |
172 | } |
173 | WARN_ON_ONCE(enable_owner != NULL); |
174 | WARN_ON_ONCE(enable_refcnt != 0); |
175 | enable_owner = current; |
176 | enable_refcnt = 1; |
177 | return flags; |
178 | } |
179 | |
180 | static void clk_enable_unlock(unsigned long flags) |
181 | __releases(enable_lock) |
182 | { |
183 | WARN_ON_ONCE(enable_owner != current); |
184 | WARN_ON_ONCE(enable_refcnt == 0); |
185 | |
186 | if (--enable_refcnt) { |
187 | __release(enable_lock); |
188 | return; |
189 | } |
190 | enable_owner = NULL; |
191 | spin_unlock_irqrestore(lock: &enable_lock, flags); |
192 | } |
193 | |
194 | static bool clk_core_rate_is_protected(struct clk_core *core) |
195 | { |
196 | return core->protect_count; |
197 | } |
198 | |
199 | static bool clk_core_is_prepared(struct clk_core *core) |
200 | { |
201 | bool ret = false; |
202 | |
203 | /* |
204 | * .is_prepared is optional for clocks that can prepare |
205 | * fall back to software usage counter if it is missing |
206 | */ |
207 | if (!core->ops->is_prepared) |
208 | return core->prepare_count; |
209 | |
210 | if (!clk_pm_runtime_get(core)) { |
211 | ret = core->ops->is_prepared(core->hw); |
212 | clk_pm_runtime_put(core); |
213 | } |
214 | |
215 | return ret; |
216 | } |
217 | |
218 | static bool clk_core_is_enabled(struct clk_core *core) |
219 | { |
220 | bool ret = false; |
221 | |
222 | /* |
223 | * .is_enabled is only mandatory for clocks that gate |
224 | * fall back to software usage counter if .is_enabled is missing |
225 | */ |
226 | if (!core->ops->is_enabled) |
227 | return core->enable_count; |
228 | |
229 | /* |
230 | * Check if clock controller's device is runtime active before |
231 | * calling .is_enabled callback. If not, assume that clock is |
232 | * disabled, because we might be called from atomic context, from |
233 | * which pm_runtime_get() is not allowed. |
234 | * This function is called mainly from clk_disable_unused_subtree, |
235 | * which ensures proper runtime pm activation of controller before |
236 | * taking enable spinlock, but the below check is needed if one tries |
237 | * to call it from other places. |
238 | */ |
239 | if (core->rpm_enabled) { |
240 | pm_runtime_get_noresume(dev: core->dev); |
241 | if (!pm_runtime_active(dev: core->dev)) { |
242 | ret = false; |
243 | goto done; |
244 | } |
245 | } |
246 | |
247 | /* |
248 | * This could be called with the enable lock held, or from atomic |
249 | * context. If the parent isn't enabled already, we can't do |
250 | * anything here. We can also assume this clock isn't enabled. |
251 | */ |
252 | if ((core->flags & CLK_OPS_PARENT_ENABLE) && core->parent) |
253 | if (!clk_core_is_enabled(core: core->parent)) { |
254 | ret = false; |
255 | goto done; |
256 | } |
257 | |
258 | ret = core->ops->is_enabled(core->hw); |
259 | done: |
260 | if (core->rpm_enabled) |
261 | pm_runtime_put(dev: core->dev); |
262 | |
263 | return ret; |
264 | } |
265 | |
266 | /*** helper functions ***/ |
267 | |
268 | const char *__clk_get_name(const struct clk *clk) |
269 | { |
270 | return !clk ? NULL : clk->core->name; |
271 | } |
272 | EXPORT_SYMBOL_GPL(__clk_get_name); |
273 | |
274 | const char *clk_hw_get_name(const struct clk_hw *hw) |
275 | { |
276 | return hw->core->name; |
277 | } |
278 | EXPORT_SYMBOL_GPL(clk_hw_get_name); |
279 | |
280 | struct clk_hw *__clk_get_hw(struct clk *clk) |
281 | { |
282 | return !clk ? NULL : clk->core->hw; |
283 | } |
284 | EXPORT_SYMBOL_GPL(__clk_get_hw); |
285 | |
286 | unsigned int clk_hw_get_num_parents(const struct clk_hw *hw) |
287 | { |
288 | return hw->core->num_parents; |
289 | } |
290 | EXPORT_SYMBOL_GPL(clk_hw_get_num_parents); |
291 | |
292 | struct clk_hw *clk_hw_get_parent(const struct clk_hw *hw) |
293 | { |
294 | return hw->core->parent ? hw->core->parent->hw : NULL; |
295 | } |
296 | EXPORT_SYMBOL_GPL(clk_hw_get_parent); |
297 | |
298 | static struct clk_core *__clk_lookup_subtree(const char *name, |
299 | struct clk_core *core) |
300 | { |
301 | struct clk_core *child; |
302 | struct clk_core *ret; |
303 | |
304 | if (!strcmp(core->name, name)) |
305 | return core; |
306 | |
307 | hlist_for_each_entry(child, &core->children, child_node) { |
308 | ret = __clk_lookup_subtree(name, core: child); |
309 | if (ret) |
310 | return ret; |
311 | } |
312 | |
313 | return NULL; |
314 | } |
315 | |
316 | static struct clk_core *clk_core_lookup(const char *name) |
317 | { |
318 | struct clk_core *root_clk; |
319 | struct clk_core *ret; |
320 | |
321 | if (!name) |
322 | return NULL; |
323 | |
324 | /* search the 'proper' clk tree first */ |
325 | hlist_for_each_entry(root_clk, &clk_root_list, child_node) { |
326 | ret = __clk_lookup_subtree(name, core: root_clk); |
327 | if (ret) |
328 | return ret; |
329 | } |
330 | |
331 | /* if not found, then search the orphan tree */ |
332 | hlist_for_each_entry(root_clk, &clk_orphan_list, child_node) { |
333 | ret = __clk_lookup_subtree(name, core: root_clk); |
334 | if (ret) |
335 | return ret; |
336 | } |
337 | |
338 | return NULL; |
339 | } |
340 | |
341 | #ifdef CONFIG_OF |
342 | static int of_parse_clkspec(const struct device_node *np, int index, |
343 | const char *name, struct of_phandle_args *out_args); |
344 | static struct clk_hw * |
345 | of_clk_get_hw_from_clkspec(struct of_phandle_args *clkspec); |
346 | #else |
347 | static inline int of_parse_clkspec(const struct device_node *np, int index, |
348 | const char *name, |
349 | struct of_phandle_args *out_args) |
350 | { |
351 | return -ENOENT; |
352 | } |
353 | static inline struct clk_hw * |
354 | of_clk_get_hw_from_clkspec(struct of_phandle_args *clkspec) |
355 | { |
356 | return ERR_PTR(-ENOENT); |
357 | } |
358 | #endif |
359 | |
360 | /** |
361 | * clk_core_get - Find the clk_core parent of a clk |
362 | * @core: clk to find parent of |
363 | * @p_index: parent index to search for |
364 | * |
365 | * This is the preferred method for clk providers to find the parent of a |
366 | * clk when that parent is external to the clk controller. The parent_names |
367 | * array is indexed and treated as a local name matching a string in the device |
368 | * node's 'clock-names' property or as the 'con_id' matching the device's |
369 | * dev_name() in a clk_lookup. This allows clk providers to use their own |
370 | * namespace instead of looking for a globally unique parent string. |
371 | * |
372 | * For example the following DT snippet would allow a clock registered by the |
373 | * clock-controller@c001 that has a clk_init_data::parent_data array |
374 | * with 'xtal' in the 'name' member to find the clock provided by the |
375 | * clock-controller@f00abcd without needing to get the globally unique name of |
376 | * the xtal clk. |
377 | * |
378 | * parent: clock-controller@f00abcd { |
379 | * reg = <0xf00abcd 0xabcd>; |
380 | * #clock-cells = <0>; |
381 | * }; |
382 | * |
383 | * clock-controller@c001 { |
384 | * reg = <0xc001 0xf00d>; |
385 | * clocks = <&parent>; |
386 | * clock-names = "xtal"; |
387 | * #clock-cells = <1>; |
388 | * }; |
389 | * |
390 | * Returns: -ENOENT when the provider can't be found or the clk doesn't |
391 | * exist in the provider or the name can't be found in the DT node or |
392 | * in a clkdev lookup. NULL when the provider knows about the clk but it |
393 | * isn't provided on this system. |
394 | * A valid clk_core pointer when the clk can be found in the provider. |
395 | */ |
396 | static struct clk_core *clk_core_get(struct clk_core *core, u8 p_index) |
397 | { |
398 | const char *name = core->parents[p_index].fw_name; |
399 | int index = core->parents[p_index].index; |
400 | struct clk_hw *hw = ERR_PTR(error: -ENOENT); |
401 | struct device *dev = core->dev; |
402 | const char *dev_id = dev ? dev_name(dev) : NULL; |
403 | struct device_node *np = core->of_node; |
404 | struct of_phandle_args clkspec; |
405 | |
406 | if (np && (name || index >= 0) && |
407 | !of_parse_clkspec(np, index, name, out_args: &clkspec)) { |
408 | hw = of_clk_get_hw_from_clkspec(clkspec: &clkspec); |
409 | of_node_put(node: clkspec.np); |
410 | } else if (name) { |
411 | /* |
412 | * If the DT search above couldn't find the provider fallback to |
413 | * looking up via clkdev based clk_lookups. |
414 | */ |
415 | hw = clk_find_hw(dev_id, con_id: name); |
416 | } |
417 | |
418 | if (IS_ERR(ptr: hw)) |
419 | return ERR_CAST(ptr: hw); |
420 | |
421 | return hw->core; |
422 | } |
423 | |
424 | static void clk_core_fill_parent_index(struct clk_core *core, u8 index) |
425 | { |
426 | struct clk_parent_map *entry = &core->parents[index]; |
427 | struct clk_core *parent; |
428 | |
429 | if (entry->hw) { |
430 | parent = entry->hw->core; |
431 | } else { |
432 | parent = clk_core_get(core, p_index: index); |
433 | if (PTR_ERR(ptr: parent) == -ENOENT && entry->name) |
434 | parent = clk_core_lookup(name: entry->name); |
435 | } |
436 | |
437 | /* |
438 | * We have a direct reference but it isn't registered yet? |
439 | * Orphan it and let clk_reparent() update the orphan status |
440 | * when the parent is registered. |
441 | */ |
442 | if (!parent) |
443 | parent = ERR_PTR(error: -EPROBE_DEFER); |
444 | |
445 | /* Only cache it if it's not an error */ |
446 | if (!IS_ERR(ptr: parent)) |
447 | entry->core = parent; |
448 | } |
449 | |
450 | static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core, |
451 | u8 index) |
452 | { |
453 | if (!core || index >= core->num_parents || !core->parents) |
454 | return NULL; |
455 | |
456 | if (!core->parents[index].core) |
457 | clk_core_fill_parent_index(core, index); |
458 | |
459 | return core->parents[index].core; |
460 | } |
461 | |
462 | struct clk_hw * |
463 | clk_hw_get_parent_by_index(const struct clk_hw *hw, unsigned int index) |
464 | { |
465 | struct clk_core *parent; |
466 | |
467 | parent = clk_core_get_parent_by_index(core: hw->core, index); |
468 | |
469 | return !parent ? NULL : parent->hw; |
470 | } |
471 | EXPORT_SYMBOL_GPL(clk_hw_get_parent_by_index); |
472 | |
473 | unsigned int __clk_get_enable_count(struct clk *clk) |
474 | { |
475 | return !clk ? 0 : clk->core->enable_count; |
476 | } |
477 | |
478 | static unsigned long clk_core_get_rate_nolock(struct clk_core *core) |
479 | { |
480 | if (!core) |
481 | return 0; |
482 | |
483 | if (!core->num_parents || core->parent) |
484 | return core->rate; |
485 | |
486 | /* |
487 | * Clk must have a parent because num_parents > 0 but the parent isn't |
488 | * known yet. Best to return 0 as the rate of this clk until we can |
489 | * properly recalc the rate based on the parent's rate. |
490 | */ |
491 | return 0; |
492 | } |
493 | |
494 | unsigned long clk_hw_get_rate(const struct clk_hw *hw) |
495 | { |
496 | return clk_core_get_rate_nolock(core: hw->core); |
497 | } |
498 | EXPORT_SYMBOL_GPL(clk_hw_get_rate); |
499 | |
500 | static unsigned long clk_core_get_accuracy_no_lock(struct clk_core *core) |
501 | { |
502 | if (!core) |
503 | return 0; |
504 | |
505 | return core->accuracy; |
506 | } |
507 | |
508 | unsigned long clk_hw_get_flags(const struct clk_hw *hw) |
509 | { |
510 | return hw->core->flags; |
511 | } |
512 | EXPORT_SYMBOL_GPL(clk_hw_get_flags); |
513 | |
514 | bool clk_hw_is_prepared(const struct clk_hw *hw) |
515 | { |
516 | return clk_core_is_prepared(core: hw->core); |
517 | } |
518 | EXPORT_SYMBOL_GPL(clk_hw_is_prepared); |
519 | |
520 | bool clk_hw_rate_is_protected(const struct clk_hw *hw) |
521 | { |
522 | return clk_core_rate_is_protected(core: hw->core); |
523 | } |
524 | EXPORT_SYMBOL_GPL(clk_hw_rate_is_protected); |
525 | |
526 | bool clk_hw_is_enabled(const struct clk_hw *hw) |
527 | { |
528 | return clk_core_is_enabled(core: hw->core); |
529 | } |
530 | EXPORT_SYMBOL_GPL(clk_hw_is_enabled); |
531 | |
532 | bool __clk_is_enabled(struct clk *clk) |
533 | { |
534 | if (!clk) |
535 | return false; |
536 | |
537 | return clk_core_is_enabled(core: clk->core); |
538 | } |
539 | EXPORT_SYMBOL_GPL(__clk_is_enabled); |
540 | |
541 | static bool mux_is_better_rate(unsigned long rate, unsigned long now, |
542 | unsigned long best, unsigned long flags) |
543 | { |
544 | if (flags & CLK_MUX_ROUND_CLOSEST) |
545 | return abs(now - rate) < abs(best - rate); |
546 | |
547 | return now <= rate && now > best; |
548 | } |
549 | |
550 | static void clk_core_init_rate_req(struct clk_core * const core, |
551 | struct clk_rate_request *req, |
552 | unsigned long rate); |
553 | |
554 | static int clk_core_round_rate_nolock(struct clk_core *core, |
555 | struct clk_rate_request *req); |
556 | |
557 | static bool clk_core_has_parent(struct clk_core *core, const struct clk_core *parent) |
558 | { |
559 | struct clk_core *tmp; |
560 | unsigned int i; |
561 | |
562 | /* Optimize for the case where the parent is already the parent. */ |
563 | if (core->parent == parent) |
564 | return true; |
565 | |
566 | for (i = 0; i < core->num_parents; i++) { |
567 | tmp = clk_core_get_parent_by_index(core, index: i); |
568 | if (!tmp) |
569 | continue; |
570 | |
571 | if (tmp == parent) |
572 | return true; |
573 | } |
574 | |
575 | return false; |
576 | } |
577 | |
578 | static void |
579 | clk_core_forward_rate_req(struct clk_core *core, |
580 | const struct clk_rate_request *old_req, |
581 | struct clk_core *parent, |
582 | struct clk_rate_request *req, |
583 | unsigned long parent_rate) |
584 | { |
585 | if (WARN_ON(!clk_core_has_parent(core, parent))) |
586 | return; |
587 | |
588 | clk_core_init_rate_req(core: parent, req, rate: parent_rate); |
589 | |
590 | if (req->min_rate < old_req->min_rate) |
591 | req->min_rate = old_req->min_rate; |
592 | |
593 | if (req->max_rate > old_req->max_rate) |
594 | req->max_rate = old_req->max_rate; |
595 | } |
596 | |
597 | static int |
598 | clk_core_determine_rate_no_reparent(struct clk_hw *hw, |
599 | struct clk_rate_request *req) |
600 | { |
601 | struct clk_core *core = hw->core; |
602 | struct clk_core *parent = core->parent; |
603 | unsigned long best; |
604 | int ret; |
605 | |
606 | if (core->flags & CLK_SET_RATE_PARENT) { |
607 | struct clk_rate_request parent_req; |
608 | |
609 | if (!parent) { |
610 | req->rate = 0; |
611 | return 0; |
612 | } |
613 | |
614 | clk_core_forward_rate_req(core, old_req: req, parent, req: &parent_req, |
615 | parent_rate: req->rate); |
616 | |
617 | trace_clk_rate_request_start(req: &parent_req); |
618 | |
619 | ret = clk_core_round_rate_nolock(core: parent, req: &parent_req); |
620 | if (ret) |
621 | return ret; |
622 | |
623 | trace_clk_rate_request_done(req: &parent_req); |
624 | |
625 | best = parent_req.rate; |
626 | } else if (parent) { |
627 | best = clk_core_get_rate_nolock(core: parent); |
628 | } else { |
629 | best = clk_core_get_rate_nolock(core); |
630 | } |
631 | |
632 | req->best_parent_rate = best; |
633 | req->rate = best; |
634 | |
635 | return 0; |
636 | } |
637 | |
638 | int clk_mux_determine_rate_flags(struct clk_hw *hw, |
639 | struct clk_rate_request *req, |
640 | unsigned long flags) |
641 | { |
642 | struct clk_core *core = hw->core, *parent, *best_parent = NULL; |
643 | int i, num_parents, ret; |
644 | unsigned long best = 0; |
645 | |
646 | /* if NO_REPARENT flag set, pass through to current parent */ |
647 | if (core->flags & CLK_SET_RATE_NO_REPARENT) |
648 | return clk_core_determine_rate_no_reparent(hw, req); |
649 | |
650 | /* find the parent that can provide the fastest rate <= rate */ |
651 | num_parents = core->num_parents; |
652 | for (i = 0; i < num_parents; i++) { |
653 | unsigned long parent_rate; |
654 | |
655 | parent = clk_core_get_parent_by_index(core, index: i); |
656 | if (!parent) |
657 | continue; |
658 | |
659 | if (core->flags & CLK_SET_RATE_PARENT) { |
660 | struct clk_rate_request parent_req; |
661 | |
662 | clk_core_forward_rate_req(core, old_req: req, parent, req: &parent_req, parent_rate: req->rate); |
663 | |
664 | trace_clk_rate_request_start(req: &parent_req); |
665 | |
666 | ret = clk_core_round_rate_nolock(core: parent, req: &parent_req); |
667 | if (ret) |
668 | continue; |
669 | |
670 | trace_clk_rate_request_done(req: &parent_req); |
671 | |
672 | parent_rate = parent_req.rate; |
673 | } else { |
674 | parent_rate = clk_core_get_rate_nolock(core: parent); |
675 | } |
676 | |
677 | if (mux_is_better_rate(rate: req->rate, now: parent_rate, |
678 | best, flags)) { |
679 | best_parent = parent; |
680 | best = parent_rate; |
681 | } |
682 | } |
683 | |
684 | if (!best_parent) |
685 | return -EINVAL; |
686 | |
687 | req->best_parent_hw = best_parent->hw; |
688 | req->best_parent_rate = best; |
689 | req->rate = best; |
690 | |
691 | return 0; |
692 | } |
693 | EXPORT_SYMBOL_GPL(clk_mux_determine_rate_flags); |
694 | |
695 | struct clk *__clk_lookup(const char *name) |
696 | { |
697 | struct clk_core *core = clk_core_lookup(name); |
698 | |
699 | return !core ? NULL : core->hw->clk; |
700 | } |
701 | |
702 | static void clk_core_get_boundaries(struct clk_core *core, |
703 | unsigned long *min_rate, |
704 | unsigned long *max_rate) |
705 | { |
706 | struct clk *clk_user; |
707 | |
708 | lockdep_assert_held(&prepare_lock); |
709 | |
710 | *min_rate = core->min_rate; |
711 | *max_rate = core->max_rate; |
712 | |
713 | hlist_for_each_entry(clk_user, &core->clks, clks_node) |
714 | *min_rate = max(*min_rate, clk_user->min_rate); |
715 | |
716 | hlist_for_each_entry(clk_user, &core->clks, clks_node) |
717 | *max_rate = min(*max_rate, clk_user->max_rate); |
718 | } |
719 | |
720 | /* |
721 | * clk_hw_get_rate_range() - returns the clock rate range for a hw clk |
722 | * @hw: the hw clk we want to get the range from |
723 | * @min_rate: pointer to the variable that will hold the minimum |
724 | * @max_rate: pointer to the variable that will hold the maximum |
725 | * |
726 | * Fills the @min_rate and @max_rate variables with the minimum and |
727 | * maximum that clock can reach. |
728 | */ |
729 | void clk_hw_get_rate_range(struct clk_hw *hw, unsigned long *min_rate, |
730 | unsigned long *max_rate) |
731 | { |
732 | clk_core_get_boundaries(core: hw->core, min_rate, max_rate); |
733 | } |
734 | EXPORT_SYMBOL_GPL(clk_hw_get_rate_range); |
735 | |
736 | static bool clk_core_check_boundaries(struct clk_core *core, |
737 | unsigned long min_rate, |
738 | unsigned long max_rate) |
739 | { |
740 | struct clk *user; |
741 | |
742 | lockdep_assert_held(&prepare_lock); |
743 | |
744 | if (min_rate > core->max_rate || max_rate < core->min_rate) |
745 | return false; |
746 | |
747 | hlist_for_each_entry(user, &core->clks, clks_node) |
748 | if (min_rate > user->max_rate || max_rate < user->min_rate) |
749 | return false; |
750 | |
751 | return true; |
752 | } |
753 | |
754 | void clk_hw_set_rate_range(struct clk_hw *hw, unsigned long min_rate, |
755 | unsigned long max_rate) |
756 | { |
757 | hw->core->min_rate = min_rate; |
758 | hw->core->max_rate = max_rate; |
759 | } |
760 | EXPORT_SYMBOL_GPL(clk_hw_set_rate_range); |
761 | |
762 | /* |
763 | * __clk_mux_determine_rate - clk_ops::determine_rate implementation for a mux type clk |
764 | * @hw: mux type clk to determine rate on |
765 | * @req: rate request, also used to return preferred parent and frequencies |
766 | * |
767 | * Helper for finding best parent to provide a given frequency. This can be used |
768 | * directly as a determine_rate callback (e.g. for a mux), or from a more |
769 | * complex clock that may combine a mux with other operations. |
770 | * |
771 | * Returns: 0 on success, -EERROR value on error |
772 | */ |
773 | int __clk_mux_determine_rate(struct clk_hw *hw, |
774 | struct clk_rate_request *req) |
775 | { |
776 | return clk_mux_determine_rate_flags(hw, req, 0); |
777 | } |
778 | EXPORT_SYMBOL_GPL(__clk_mux_determine_rate); |
779 | |
780 | int __clk_mux_determine_rate_closest(struct clk_hw *hw, |
781 | struct clk_rate_request *req) |
782 | { |
783 | return clk_mux_determine_rate_flags(hw, req, CLK_MUX_ROUND_CLOSEST); |
784 | } |
785 | EXPORT_SYMBOL_GPL(__clk_mux_determine_rate_closest); |
786 | |
787 | /* |
788 | * clk_hw_determine_rate_no_reparent - clk_ops::determine_rate implementation for a clk that doesn't reparent |
789 | * @hw: mux type clk to determine rate on |
790 | * @req: rate request, also used to return preferred frequency |
791 | * |
792 | * Helper for finding best parent rate to provide a given frequency. |
793 | * This can be used directly as a determine_rate callback (e.g. for a |
794 | * mux), or from a more complex clock that may combine a mux with other |
795 | * operations. |
796 | * |
797 | * Returns: 0 on success, -EERROR value on error |
798 | */ |
799 | int clk_hw_determine_rate_no_reparent(struct clk_hw *hw, |
800 | struct clk_rate_request *req) |
801 | { |
802 | return clk_core_determine_rate_no_reparent(hw, req); |
803 | } |
804 | EXPORT_SYMBOL_GPL(clk_hw_determine_rate_no_reparent); |
805 | |
806 | /*** clk api ***/ |
807 | |
808 | static void clk_core_rate_unprotect(struct clk_core *core) |
809 | { |
810 | lockdep_assert_held(&prepare_lock); |
811 | |
812 | if (!core) |
813 | return; |
814 | |
815 | if (WARN(core->protect_count == 0, |
816 | "%s already unprotected\n" , core->name)) |
817 | return; |
818 | |
819 | if (--core->protect_count > 0) |
820 | return; |
821 | |
822 | clk_core_rate_unprotect(core: core->parent); |
823 | } |
824 | |
825 | static int clk_core_rate_nuke_protect(struct clk_core *core) |
826 | { |
827 | int ret; |
828 | |
829 | lockdep_assert_held(&prepare_lock); |
830 | |
831 | if (!core) |
832 | return -EINVAL; |
833 | |
834 | if (core->protect_count == 0) |
835 | return 0; |
836 | |
837 | ret = core->protect_count; |
838 | core->protect_count = 1; |
839 | clk_core_rate_unprotect(core); |
840 | |
841 | return ret; |
842 | } |
843 | |
844 | /** |
845 | * clk_rate_exclusive_put - release exclusivity over clock rate control |
846 | * @clk: the clk over which the exclusivity is released |
847 | * |
848 | * clk_rate_exclusive_put() completes a critical section during which a clock |
849 | * consumer cannot tolerate any other consumer making any operation on the |
850 | * clock which could result in a rate change or rate glitch. Exclusive clocks |
851 | * cannot have their rate changed, either directly or indirectly due to changes |
852 | * further up the parent chain of clocks. As a result, clocks up parent chain |
853 | * also get under exclusive control of the calling consumer. |
854 | * |
855 | * If exlusivity is claimed more than once on clock, even by the same consumer, |
856 | * the rate effectively gets locked as exclusivity can't be preempted. |
857 | * |
858 | * Calls to clk_rate_exclusive_put() must be balanced with calls to |
859 | * clk_rate_exclusive_get(). Calls to this function may sleep, and do not return |
860 | * error status. |
861 | */ |
862 | void clk_rate_exclusive_put(struct clk *clk) |
863 | { |
864 | if (!clk) |
865 | return; |
866 | |
867 | clk_prepare_lock(); |
868 | |
869 | /* |
870 | * if there is something wrong with this consumer protect count, stop |
871 | * here before messing with the provider |
872 | */ |
873 | if (WARN_ON(clk->exclusive_count <= 0)) |
874 | goto out; |
875 | |
876 | clk_core_rate_unprotect(core: clk->core); |
877 | clk->exclusive_count--; |
878 | out: |
879 | clk_prepare_unlock(); |
880 | } |
881 | EXPORT_SYMBOL_GPL(clk_rate_exclusive_put); |
882 | |
883 | static void clk_core_rate_protect(struct clk_core *core) |
884 | { |
885 | lockdep_assert_held(&prepare_lock); |
886 | |
887 | if (!core) |
888 | return; |
889 | |
890 | if (core->protect_count == 0) |
891 | clk_core_rate_protect(core: core->parent); |
892 | |
893 | core->protect_count++; |
894 | } |
895 | |
896 | static void clk_core_rate_restore_protect(struct clk_core *core, int count) |
897 | { |
898 | lockdep_assert_held(&prepare_lock); |
899 | |
900 | if (!core) |
901 | return; |
902 | |
903 | if (count == 0) |
904 | return; |
905 | |
906 | clk_core_rate_protect(core); |
907 | core->protect_count = count; |
908 | } |
909 | |
910 | /** |
911 | * clk_rate_exclusive_get - get exclusivity over the clk rate control |
912 | * @clk: the clk over which the exclusity of rate control is requested |
913 | * |
914 | * clk_rate_exclusive_get() begins a critical section during which a clock |
915 | * consumer cannot tolerate any other consumer making any operation on the |
916 | * clock which could result in a rate change or rate glitch. Exclusive clocks |
917 | * cannot have their rate changed, either directly or indirectly due to changes |
918 | * further up the parent chain of clocks. As a result, clocks up parent chain |
919 | * also get under exclusive control of the calling consumer. |
920 | * |
921 | * If exlusivity is claimed more than once on clock, even by the same consumer, |
922 | * the rate effectively gets locked as exclusivity can't be preempted. |
923 | * |
924 | * Calls to clk_rate_exclusive_get() should be balanced with calls to |
925 | * clk_rate_exclusive_put(). Calls to this function may sleep. |
926 | * Returns 0 on success, -EERROR otherwise |
927 | */ |
928 | int clk_rate_exclusive_get(struct clk *clk) |
929 | { |
930 | if (!clk) |
931 | return 0; |
932 | |
933 | clk_prepare_lock(); |
934 | clk_core_rate_protect(core: clk->core); |
935 | clk->exclusive_count++; |
936 | clk_prepare_unlock(); |
937 | |
938 | return 0; |
939 | } |
940 | EXPORT_SYMBOL_GPL(clk_rate_exclusive_get); |
941 | |
942 | static void clk_core_unprepare(struct clk_core *core) |
943 | { |
944 | lockdep_assert_held(&prepare_lock); |
945 | |
946 | if (!core) |
947 | return; |
948 | |
949 | if (WARN(core->prepare_count == 0, |
950 | "%s already unprepared\n" , core->name)) |
951 | return; |
952 | |
953 | if (WARN(core->prepare_count == 1 && core->flags & CLK_IS_CRITICAL, |
954 | "Unpreparing critical %s\n" , core->name)) |
955 | return; |
956 | |
957 | if (core->flags & CLK_SET_RATE_GATE) |
958 | clk_core_rate_unprotect(core); |
959 | |
960 | if (--core->prepare_count > 0) |
961 | return; |
962 | |
963 | WARN(core->enable_count > 0, "Unpreparing enabled %s\n" , core->name); |
964 | |
965 | trace_clk_unprepare(core); |
966 | |
967 | if (core->ops->unprepare) |
968 | core->ops->unprepare(core->hw); |
969 | |
970 | trace_clk_unprepare_complete(core); |
971 | clk_core_unprepare(core: core->parent); |
972 | clk_pm_runtime_put(core); |
973 | } |
974 | |
975 | static void clk_core_unprepare_lock(struct clk_core *core) |
976 | { |
977 | clk_prepare_lock(); |
978 | clk_core_unprepare(core); |
979 | clk_prepare_unlock(); |
980 | } |
981 | |
982 | /** |
983 | * clk_unprepare - undo preparation of a clock source |
984 | * @clk: the clk being unprepared |
985 | * |
986 | * clk_unprepare may sleep, which differentiates it from clk_disable. In a |
987 | * simple case, clk_unprepare can be used instead of clk_disable to gate a clk |
988 | * if the operation may sleep. One example is a clk which is accessed over |
989 | * I2c. In the complex case a clk gate operation may require a fast and a slow |
990 | * part. It is this reason that clk_unprepare and clk_disable are not mutually |
991 | * exclusive. In fact clk_disable must be called before clk_unprepare. |
992 | */ |
993 | void clk_unprepare(struct clk *clk) |
994 | { |
995 | if (IS_ERR_OR_NULL(ptr: clk)) |
996 | return; |
997 | |
998 | clk_core_unprepare_lock(core: clk->core); |
999 | } |
1000 | EXPORT_SYMBOL_GPL(clk_unprepare); |
1001 | |
1002 | static int clk_core_prepare(struct clk_core *core) |
1003 | { |
1004 | int ret = 0; |
1005 | |
1006 | lockdep_assert_held(&prepare_lock); |
1007 | |
1008 | if (!core) |
1009 | return 0; |
1010 | |
1011 | if (core->prepare_count == 0) { |
1012 | ret = clk_pm_runtime_get(core); |
1013 | if (ret) |
1014 | return ret; |
1015 | |
1016 | ret = clk_core_prepare(core: core->parent); |
1017 | if (ret) |
1018 | goto runtime_put; |
1019 | |
1020 | trace_clk_prepare(core); |
1021 | |
1022 | if (core->ops->prepare) |
1023 | ret = core->ops->prepare(core->hw); |
1024 | |
1025 | trace_clk_prepare_complete(core); |
1026 | |
1027 | if (ret) |
1028 | goto unprepare; |
1029 | } |
1030 | |
1031 | core->prepare_count++; |
1032 | |
1033 | /* |
1034 | * CLK_SET_RATE_GATE is a special case of clock protection |
1035 | * Instead of a consumer claiming exclusive rate control, it is |
1036 | * actually the provider which prevents any consumer from making any |
1037 | * operation which could result in a rate change or rate glitch while |
1038 | * the clock is prepared. |
1039 | */ |
1040 | if (core->flags & CLK_SET_RATE_GATE) |
1041 | clk_core_rate_protect(core); |
1042 | |
1043 | return 0; |
1044 | unprepare: |
1045 | clk_core_unprepare(core: core->parent); |
1046 | runtime_put: |
1047 | clk_pm_runtime_put(core); |
1048 | return ret; |
1049 | } |
1050 | |
1051 | static int clk_core_prepare_lock(struct clk_core *core) |
1052 | { |
1053 | int ret; |
1054 | |
1055 | clk_prepare_lock(); |
1056 | ret = clk_core_prepare(core); |
1057 | clk_prepare_unlock(); |
1058 | |
1059 | return ret; |
1060 | } |
1061 | |
1062 | /** |
1063 | * clk_prepare - prepare a clock source |
1064 | * @clk: the clk being prepared |
1065 | * |
1066 | * clk_prepare may sleep, which differentiates it from clk_enable. In a simple |
1067 | * case, clk_prepare can be used instead of clk_enable to ungate a clk if the |
1068 | * operation may sleep. One example is a clk which is accessed over I2c. In |
1069 | * the complex case a clk ungate operation may require a fast and a slow part. |
1070 | * It is this reason that clk_prepare and clk_enable are not mutually |
1071 | * exclusive. In fact clk_prepare must be called before clk_enable. |
1072 | * Returns 0 on success, -EERROR otherwise. |
1073 | */ |
1074 | int clk_prepare(struct clk *clk) |
1075 | { |
1076 | if (!clk) |
1077 | return 0; |
1078 | |
1079 | return clk_core_prepare_lock(core: clk->core); |
1080 | } |
1081 | EXPORT_SYMBOL_GPL(clk_prepare); |
1082 | |
1083 | static void clk_core_disable(struct clk_core *core) |
1084 | { |
1085 | lockdep_assert_held(&enable_lock); |
1086 | |
1087 | if (!core) |
1088 | return; |
1089 | |
1090 | if (WARN(core->enable_count == 0, "%s already disabled\n" , core->name)) |
1091 | return; |
1092 | |
1093 | if (WARN(core->enable_count == 1 && core->flags & CLK_IS_CRITICAL, |
1094 | "Disabling critical %s\n" , core->name)) |
1095 | return; |
1096 | |
1097 | if (--core->enable_count > 0) |
1098 | return; |
1099 | |
1100 | trace_clk_disable(core); |
1101 | |
1102 | if (core->ops->disable) |
1103 | core->ops->disable(core->hw); |
1104 | |
1105 | trace_clk_disable_complete(core); |
1106 | |
1107 | clk_core_disable(core: core->parent); |
1108 | } |
1109 | |
1110 | static void clk_core_disable_lock(struct clk_core *core) |
1111 | { |
1112 | unsigned long flags; |
1113 | |
1114 | flags = clk_enable_lock(); |
1115 | clk_core_disable(core); |
1116 | clk_enable_unlock(flags); |
1117 | } |
1118 | |
1119 | /** |
1120 | * clk_disable - gate a clock |
1121 | * @clk: the clk being gated |
1122 | * |
1123 | * clk_disable must not sleep, which differentiates it from clk_unprepare. In |
1124 | * a simple case, clk_disable can be used instead of clk_unprepare to gate a |
1125 | * clk if the operation is fast and will never sleep. One example is a |
1126 | * SoC-internal clk which is controlled via simple register writes. In the |
1127 | * complex case a clk gate operation may require a fast and a slow part. It is |
1128 | * this reason that clk_unprepare and clk_disable are not mutually exclusive. |
1129 | * In fact clk_disable must be called before clk_unprepare. |
1130 | */ |
1131 | void clk_disable(struct clk *clk) |
1132 | { |
1133 | if (IS_ERR_OR_NULL(ptr: clk)) |
1134 | return; |
1135 | |
1136 | clk_core_disable_lock(core: clk->core); |
1137 | } |
1138 | EXPORT_SYMBOL_GPL(clk_disable); |
1139 | |
1140 | static int clk_core_enable(struct clk_core *core) |
1141 | { |
1142 | int ret = 0; |
1143 | |
1144 | lockdep_assert_held(&enable_lock); |
1145 | |
1146 | if (!core) |
1147 | return 0; |
1148 | |
1149 | if (WARN(core->prepare_count == 0, |
1150 | "Enabling unprepared %s\n" , core->name)) |
1151 | return -ESHUTDOWN; |
1152 | |
1153 | if (core->enable_count == 0) { |
1154 | ret = clk_core_enable(core: core->parent); |
1155 | |
1156 | if (ret) |
1157 | return ret; |
1158 | |
1159 | trace_clk_enable(core); |
1160 | |
1161 | if (core->ops->enable) |
1162 | ret = core->ops->enable(core->hw); |
1163 | |
1164 | trace_clk_enable_complete(core); |
1165 | |
1166 | if (ret) { |
1167 | clk_core_disable(core: core->parent); |
1168 | return ret; |
1169 | } |
1170 | } |
1171 | |
1172 | core->enable_count++; |
1173 | return 0; |
1174 | } |
1175 | |
1176 | static int clk_core_enable_lock(struct clk_core *core) |
1177 | { |
1178 | unsigned long flags; |
1179 | int ret; |
1180 | |
1181 | flags = clk_enable_lock(); |
1182 | ret = clk_core_enable(core); |
1183 | clk_enable_unlock(flags); |
1184 | |
1185 | return ret; |
1186 | } |
1187 | |
1188 | /** |
1189 | * clk_gate_restore_context - restore context for poweroff |
1190 | * @hw: the clk_hw pointer of clock whose state is to be restored |
1191 | * |
1192 | * The clock gate restore context function enables or disables |
1193 | * the gate clocks based on the enable_count. This is done in cases |
1194 | * where the clock context is lost and based on the enable_count |
1195 | * the clock either needs to be enabled/disabled. This |
1196 | * helps restore the state of gate clocks. |
1197 | */ |
1198 | void clk_gate_restore_context(struct clk_hw *hw) |
1199 | { |
1200 | struct clk_core *core = hw->core; |
1201 | |
1202 | if (core->enable_count) |
1203 | core->ops->enable(hw); |
1204 | else |
1205 | core->ops->disable(hw); |
1206 | } |
1207 | EXPORT_SYMBOL_GPL(clk_gate_restore_context); |
1208 | |
1209 | static int clk_core_save_context(struct clk_core *core) |
1210 | { |
1211 | struct clk_core *child; |
1212 | int ret = 0; |
1213 | |
1214 | hlist_for_each_entry(child, &core->children, child_node) { |
1215 | ret = clk_core_save_context(core: child); |
1216 | if (ret < 0) |
1217 | return ret; |
1218 | } |
1219 | |
1220 | if (core->ops && core->ops->save_context) |
1221 | ret = core->ops->save_context(core->hw); |
1222 | |
1223 | return ret; |
1224 | } |
1225 | |
1226 | static void clk_core_restore_context(struct clk_core *core) |
1227 | { |
1228 | struct clk_core *child; |
1229 | |
1230 | if (core->ops && core->ops->restore_context) |
1231 | core->ops->restore_context(core->hw); |
1232 | |
1233 | hlist_for_each_entry(child, &core->children, child_node) |
1234 | clk_core_restore_context(core: child); |
1235 | } |
1236 | |
1237 | /** |
1238 | * clk_save_context - save clock context for poweroff |
1239 | * |
1240 | * Saves the context of the clock register for powerstates in which the |
1241 | * contents of the registers will be lost. Occurs deep within the suspend |
1242 | * code. Returns 0 on success. |
1243 | */ |
1244 | int clk_save_context(void) |
1245 | { |
1246 | struct clk_core *clk; |
1247 | int ret; |
1248 | |
1249 | hlist_for_each_entry(clk, &clk_root_list, child_node) { |
1250 | ret = clk_core_save_context(core: clk); |
1251 | if (ret < 0) |
1252 | return ret; |
1253 | } |
1254 | |
1255 | hlist_for_each_entry(clk, &clk_orphan_list, child_node) { |
1256 | ret = clk_core_save_context(core: clk); |
1257 | if (ret < 0) |
1258 | return ret; |
1259 | } |
1260 | |
1261 | return 0; |
1262 | } |
1263 | EXPORT_SYMBOL_GPL(clk_save_context); |
1264 | |
1265 | /** |
1266 | * clk_restore_context - restore clock context after poweroff |
1267 | * |
1268 | * Restore the saved clock context upon resume. |
1269 | * |
1270 | */ |
1271 | void clk_restore_context(void) |
1272 | { |
1273 | struct clk_core *core; |
1274 | |
1275 | hlist_for_each_entry(core, &clk_root_list, child_node) |
1276 | clk_core_restore_context(core); |
1277 | |
1278 | hlist_for_each_entry(core, &clk_orphan_list, child_node) |
1279 | clk_core_restore_context(core); |
1280 | } |
1281 | EXPORT_SYMBOL_GPL(clk_restore_context); |
1282 | |
1283 | /** |
1284 | * clk_enable - ungate a clock |
1285 | * @clk: the clk being ungated |
1286 | * |
1287 | * clk_enable must not sleep, which differentiates it from clk_prepare. In a |
1288 | * simple case, clk_enable can be used instead of clk_prepare to ungate a clk |
1289 | * if the operation will never sleep. One example is a SoC-internal clk which |
1290 | * is controlled via simple register writes. In the complex case a clk ungate |
1291 | * operation may require a fast and a slow part. It is this reason that |
1292 | * clk_enable and clk_prepare are not mutually exclusive. In fact clk_prepare |
1293 | * must be called before clk_enable. Returns 0 on success, -EERROR |
1294 | * otherwise. |
1295 | */ |
1296 | int clk_enable(struct clk *clk) |
1297 | { |
1298 | if (!clk) |
1299 | return 0; |
1300 | |
1301 | return clk_core_enable_lock(core: clk->core); |
1302 | } |
1303 | EXPORT_SYMBOL_GPL(clk_enable); |
1304 | |
1305 | /** |
1306 | * clk_is_enabled_when_prepared - indicate if preparing a clock also enables it. |
1307 | * @clk: clock source |
1308 | * |
1309 | * Returns true if clk_prepare() implicitly enables the clock, effectively |
1310 | * making clk_enable()/clk_disable() no-ops, false otherwise. |
1311 | * |
1312 | * This is of interest mainly to power management code where actually |
1313 | * disabling the clock also requires unpreparing it to have any material |
1314 | * effect. |
1315 | * |
1316 | * Regardless of the value returned here, the caller must always invoke |
1317 | * clk_enable() or clk_prepare_enable() and counterparts for usage counts |
1318 | * to be right. |
1319 | */ |
1320 | bool clk_is_enabled_when_prepared(struct clk *clk) |
1321 | { |
1322 | return clk && !(clk->core->ops->enable && clk->core->ops->disable); |
1323 | } |
1324 | EXPORT_SYMBOL_GPL(clk_is_enabled_when_prepared); |
1325 | |
1326 | static int clk_core_prepare_enable(struct clk_core *core) |
1327 | { |
1328 | int ret; |
1329 | |
1330 | ret = clk_core_prepare_lock(core); |
1331 | if (ret) |
1332 | return ret; |
1333 | |
1334 | ret = clk_core_enable_lock(core); |
1335 | if (ret) |
1336 | clk_core_unprepare_lock(core); |
1337 | |
1338 | return ret; |
1339 | } |
1340 | |
1341 | static void clk_core_disable_unprepare(struct clk_core *core) |
1342 | { |
1343 | clk_core_disable_lock(core); |
1344 | clk_core_unprepare_lock(core); |
1345 | } |
1346 | |
1347 | static void __init clk_unprepare_unused_subtree(struct clk_core *core) |
1348 | { |
1349 | struct clk_core *child; |
1350 | |
1351 | lockdep_assert_held(&prepare_lock); |
1352 | |
1353 | hlist_for_each_entry(child, &core->children, child_node) |
1354 | clk_unprepare_unused_subtree(core: child); |
1355 | |
1356 | if (core->prepare_count) |
1357 | return; |
1358 | |
1359 | if (core->flags & CLK_IGNORE_UNUSED) |
1360 | return; |
1361 | |
1362 | if (clk_pm_runtime_get(core)) |
1363 | return; |
1364 | |
1365 | if (clk_core_is_prepared(core)) { |
1366 | trace_clk_unprepare(core); |
1367 | if (core->ops->unprepare_unused) |
1368 | core->ops->unprepare_unused(core->hw); |
1369 | else if (core->ops->unprepare) |
1370 | core->ops->unprepare(core->hw); |
1371 | trace_clk_unprepare_complete(core); |
1372 | } |
1373 | |
1374 | clk_pm_runtime_put(core); |
1375 | } |
1376 | |
1377 | static void __init clk_disable_unused_subtree(struct clk_core *core) |
1378 | { |
1379 | struct clk_core *child; |
1380 | unsigned long flags; |
1381 | |
1382 | lockdep_assert_held(&prepare_lock); |
1383 | |
1384 | hlist_for_each_entry(child, &core->children, child_node) |
1385 | clk_disable_unused_subtree(core: child); |
1386 | |
1387 | if (core->flags & CLK_OPS_PARENT_ENABLE) |
1388 | clk_core_prepare_enable(core: core->parent); |
1389 | |
1390 | if (clk_pm_runtime_get(core)) |
1391 | goto unprepare_out; |
1392 | |
1393 | flags = clk_enable_lock(); |
1394 | |
1395 | if (core->enable_count) |
1396 | goto unlock_out; |
1397 | |
1398 | if (core->flags & CLK_IGNORE_UNUSED) |
1399 | goto unlock_out; |
1400 | |
1401 | /* |
1402 | * some gate clocks have special needs during the disable-unused |
1403 | * sequence. call .disable_unused if available, otherwise fall |
1404 | * back to .disable |
1405 | */ |
1406 | if (clk_core_is_enabled(core)) { |
1407 | trace_clk_disable(core); |
1408 | if (core->ops->disable_unused) |
1409 | core->ops->disable_unused(core->hw); |
1410 | else if (core->ops->disable) |
1411 | core->ops->disable(core->hw); |
1412 | trace_clk_disable_complete(core); |
1413 | } |
1414 | |
1415 | unlock_out: |
1416 | clk_enable_unlock(flags); |
1417 | clk_pm_runtime_put(core); |
1418 | unprepare_out: |
1419 | if (core->flags & CLK_OPS_PARENT_ENABLE) |
1420 | clk_core_disable_unprepare(core: core->parent); |
1421 | } |
1422 | |
1423 | static bool clk_ignore_unused __initdata; |
1424 | static int __init clk_ignore_unused_setup(char *__unused) |
1425 | { |
1426 | clk_ignore_unused = true; |
1427 | return 1; |
1428 | } |
1429 | __setup("clk_ignore_unused" , clk_ignore_unused_setup); |
1430 | |
1431 | static int __init clk_disable_unused(void) |
1432 | { |
1433 | struct clk_core *core; |
1434 | |
1435 | if (clk_ignore_unused) { |
1436 | pr_warn("clk: Not disabling unused clocks\n" ); |
1437 | return 0; |
1438 | } |
1439 | |
1440 | pr_info("clk: Disabling unused clocks\n" ); |
1441 | |
1442 | clk_prepare_lock(); |
1443 | |
1444 | hlist_for_each_entry(core, &clk_root_list, child_node) |
1445 | clk_disable_unused_subtree(core); |
1446 | |
1447 | hlist_for_each_entry(core, &clk_orphan_list, child_node) |
1448 | clk_disable_unused_subtree(core); |
1449 | |
1450 | hlist_for_each_entry(core, &clk_root_list, child_node) |
1451 | clk_unprepare_unused_subtree(core); |
1452 | |
1453 | hlist_for_each_entry(core, &clk_orphan_list, child_node) |
1454 | clk_unprepare_unused_subtree(core); |
1455 | |
1456 | clk_prepare_unlock(); |
1457 | |
1458 | return 0; |
1459 | } |
1460 | late_initcall_sync(clk_disable_unused); |
1461 | |
1462 | static int clk_core_determine_round_nolock(struct clk_core *core, |
1463 | struct clk_rate_request *req) |
1464 | { |
1465 | long rate; |
1466 | |
1467 | lockdep_assert_held(&prepare_lock); |
1468 | |
1469 | if (!core) |
1470 | return 0; |
1471 | |
1472 | /* |
1473 | * Some clock providers hand-craft their clk_rate_requests and |
1474 | * might not fill min_rate and max_rate. |
1475 | * |
1476 | * If it's the case, clamping the rate is equivalent to setting |
1477 | * the rate to 0 which is bad. Skip the clamping but complain so |
1478 | * that it gets fixed, hopefully. |
1479 | */ |
1480 | if (!req->min_rate && !req->max_rate) |
1481 | pr_warn("%s: %s: clk_rate_request has initialized min or max rate.\n" , |
1482 | __func__, core->name); |
1483 | else |
1484 | req->rate = clamp(req->rate, req->min_rate, req->max_rate); |
1485 | |
1486 | /* |
1487 | * At this point, core protection will be disabled |
1488 | * - if the provider is not protected at all |
1489 | * - if the calling consumer is the only one which has exclusivity |
1490 | * over the provider |
1491 | */ |
1492 | if (clk_core_rate_is_protected(core)) { |
1493 | req->rate = core->rate; |
1494 | } else if (core->ops->determine_rate) { |
1495 | return core->ops->determine_rate(core->hw, req); |
1496 | } else if (core->ops->round_rate) { |
1497 | rate = core->ops->round_rate(core->hw, req->rate, |
1498 | &req->best_parent_rate); |
1499 | if (rate < 0) |
1500 | return rate; |
1501 | |
1502 | req->rate = rate; |
1503 | } else { |
1504 | return -EINVAL; |
1505 | } |
1506 | |
1507 | return 0; |
1508 | } |
1509 | |
1510 | static void clk_core_init_rate_req(struct clk_core * const core, |
1511 | struct clk_rate_request *req, |
1512 | unsigned long rate) |
1513 | { |
1514 | struct clk_core *parent; |
1515 | |
1516 | if (WARN_ON(!req)) |
1517 | return; |
1518 | |
1519 | memset(req, 0, sizeof(*req)); |
1520 | req->max_rate = ULONG_MAX; |
1521 | |
1522 | if (!core) |
1523 | return; |
1524 | |
1525 | req->core = core; |
1526 | req->rate = rate; |
1527 | clk_core_get_boundaries(core, min_rate: &req->min_rate, max_rate: &req->max_rate); |
1528 | |
1529 | parent = core->parent; |
1530 | if (parent) { |
1531 | req->best_parent_hw = parent->hw; |
1532 | req->best_parent_rate = parent->rate; |
1533 | } else { |
1534 | req->best_parent_hw = NULL; |
1535 | req->best_parent_rate = 0; |
1536 | } |
1537 | } |
1538 | |
1539 | /** |
1540 | * clk_hw_init_rate_request - Initializes a clk_rate_request |
1541 | * @hw: the clk for which we want to submit a rate request |
1542 | * @req: the clk_rate_request structure we want to initialise |
1543 | * @rate: the rate which is to be requested |
1544 | * |
1545 | * Initializes a clk_rate_request structure to submit to |
1546 | * __clk_determine_rate() or similar functions. |
1547 | */ |
1548 | void clk_hw_init_rate_request(const struct clk_hw *hw, |
1549 | struct clk_rate_request *req, |
1550 | unsigned long rate) |
1551 | { |
1552 | if (WARN_ON(!hw || !req)) |
1553 | return; |
1554 | |
1555 | clk_core_init_rate_req(core: hw->core, req, rate); |
1556 | } |
1557 | EXPORT_SYMBOL_GPL(clk_hw_init_rate_request); |
1558 | |
1559 | /** |
1560 | * clk_hw_forward_rate_request - Forwards a clk_rate_request to a clock's parent |
1561 | * @hw: the original clock that got the rate request |
1562 | * @old_req: the original clk_rate_request structure we want to forward |
1563 | * @parent: the clk we want to forward @old_req to |
1564 | * @req: the clk_rate_request structure we want to initialise |
1565 | * @parent_rate: The rate which is to be requested to @parent |
1566 | * |
1567 | * Initializes a clk_rate_request structure to submit to a clock parent |
1568 | * in __clk_determine_rate() or similar functions. |
1569 | */ |
1570 | void clk_hw_forward_rate_request(const struct clk_hw *hw, |
1571 | const struct clk_rate_request *old_req, |
1572 | const struct clk_hw *parent, |
1573 | struct clk_rate_request *req, |
1574 | unsigned long parent_rate) |
1575 | { |
1576 | if (WARN_ON(!hw || !old_req || !parent || !req)) |
1577 | return; |
1578 | |
1579 | clk_core_forward_rate_req(core: hw->core, old_req, |
1580 | parent: parent->core, req, |
1581 | parent_rate); |
1582 | } |
1583 | EXPORT_SYMBOL_GPL(clk_hw_forward_rate_request); |
1584 | |
1585 | static bool clk_core_can_round(struct clk_core * const core) |
1586 | { |
1587 | return core->ops->determine_rate || core->ops->round_rate; |
1588 | } |
1589 | |
1590 | static int clk_core_round_rate_nolock(struct clk_core *core, |
1591 | struct clk_rate_request *req) |
1592 | { |
1593 | int ret; |
1594 | |
1595 | lockdep_assert_held(&prepare_lock); |
1596 | |
1597 | if (!core) { |
1598 | req->rate = 0; |
1599 | return 0; |
1600 | } |
1601 | |
1602 | if (clk_core_can_round(core)) |
1603 | return clk_core_determine_round_nolock(core, req); |
1604 | |
1605 | if (core->flags & CLK_SET_RATE_PARENT) { |
1606 | struct clk_rate_request parent_req; |
1607 | |
1608 | clk_core_forward_rate_req(core, old_req: req, parent: core->parent, req: &parent_req, parent_rate: req->rate); |
1609 | |
1610 | trace_clk_rate_request_start(req: &parent_req); |
1611 | |
1612 | ret = clk_core_round_rate_nolock(core: core->parent, req: &parent_req); |
1613 | if (ret) |
1614 | return ret; |
1615 | |
1616 | trace_clk_rate_request_done(req: &parent_req); |
1617 | |
1618 | req->best_parent_rate = parent_req.rate; |
1619 | req->rate = parent_req.rate; |
1620 | |
1621 | return 0; |
1622 | } |
1623 | |
1624 | req->rate = core->rate; |
1625 | return 0; |
1626 | } |
1627 | |
1628 | /** |
1629 | * __clk_determine_rate - get the closest rate actually supported by a clock |
1630 | * @hw: determine the rate of this clock |
1631 | * @req: target rate request |
1632 | * |
1633 | * Useful for clk_ops such as .set_rate and .determine_rate. |
1634 | */ |
1635 | int __clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) |
1636 | { |
1637 | if (!hw) { |
1638 | req->rate = 0; |
1639 | return 0; |
1640 | } |
1641 | |
1642 | return clk_core_round_rate_nolock(core: hw->core, req); |
1643 | } |
1644 | EXPORT_SYMBOL_GPL(__clk_determine_rate); |
1645 | |
1646 | /** |
1647 | * clk_hw_round_rate() - round the given rate for a hw clk |
1648 | * @hw: the hw clk for which we are rounding a rate |
1649 | * @rate: the rate which is to be rounded |
1650 | * |
1651 | * Takes in a rate as input and rounds it to a rate that the clk can actually |
1652 | * use. |
1653 | * |
1654 | * Context: prepare_lock must be held. |
1655 | * For clk providers to call from within clk_ops such as .round_rate, |
1656 | * .determine_rate. |
1657 | * |
1658 | * Return: returns rounded rate of hw clk if clk supports round_rate operation |
1659 | * else returns the parent rate. |
1660 | */ |
1661 | unsigned long clk_hw_round_rate(struct clk_hw *hw, unsigned long rate) |
1662 | { |
1663 | int ret; |
1664 | struct clk_rate_request req; |
1665 | |
1666 | clk_core_init_rate_req(core: hw->core, req: &req, rate); |
1667 | |
1668 | trace_clk_rate_request_start(req: &req); |
1669 | |
1670 | ret = clk_core_round_rate_nolock(core: hw->core, req: &req); |
1671 | if (ret) |
1672 | return 0; |
1673 | |
1674 | trace_clk_rate_request_done(req: &req); |
1675 | |
1676 | return req.rate; |
1677 | } |
1678 | EXPORT_SYMBOL_GPL(clk_hw_round_rate); |
1679 | |
1680 | /** |
1681 | * clk_round_rate - round the given rate for a clk |
1682 | * @clk: the clk for which we are rounding a rate |
1683 | * @rate: the rate which is to be rounded |
1684 | * |
1685 | * Takes in a rate as input and rounds it to a rate that the clk can actually |
1686 | * use which is then returned. If clk doesn't support round_rate operation |
1687 | * then the parent rate is returned. |
1688 | */ |
1689 | long clk_round_rate(struct clk *clk, unsigned long rate) |
1690 | { |
1691 | struct clk_rate_request req; |
1692 | int ret; |
1693 | |
1694 | if (!clk) |
1695 | return 0; |
1696 | |
1697 | clk_prepare_lock(); |
1698 | |
1699 | if (clk->exclusive_count) |
1700 | clk_core_rate_unprotect(core: clk->core); |
1701 | |
1702 | clk_core_init_rate_req(core: clk->core, req: &req, rate); |
1703 | |
1704 | trace_clk_rate_request_start(req: &req); |
1705 | |
1706 | ret = clk_core_round_rate_nolock(core: clk->core, req: &req); |
1707 | |
1708 | trace_clk_rate_request_done(req: &req); |
1709 | |
1710 | if (clk->exclusive_count) |
1711 | clk_core_rate_protect(core: clk->core); |
1712 | |
1713 | clk_prepare_unlock(); |
1714 | |
1715 | if (ret) |
1716 | return ret; |
1717 | |
1718 | return req.rate; |
1719 | } |
1720 | EXPORT_SYMBOL_GPL(clk_round_rate); |
1721 | |
1722 | /** |
1723 | * __clk_notify - call clk notifier chain |
1724 | * @core: clk that is changing rate |
1725 | * @msg: clk notifier type (see include/linux/clk.h) |
1726 | * @old_rate: old clk rate |
1727 | * @new_rate: new clk rate |
1728 | * |
1729 | * Triggers a notifier call chain on the clk rate-change notification |
1730 | * for 'clk'. Passes a pointer to the struct clk and the previous |
1731 | * and current rates to the notifier callback. Intended to be called by |
1732 | * internal clock code only. Returns NOTIFY_DONE from the last driver |
1733 | * called if all went well, or NOTIFY_STOP or NOTIFY_BAD immediately if |
1734 | * a driver returns that. |
1735 | */ |
1736 | static int __clk_notify(struct clk_core *core, unsigned long msg, |
1737 | unsigned long old_rate, unsigned long new_rate) |
1738 | { |
1739 | struct clk_notifier *cn; |
1740 | struct clk_notifier_data cnd; |
1741 | int ret = NOTIFY_DONE; |
1742 | |
1743 | cnd.old_rate = old_rate; |
1744 | cnd.new_rate = new_rate; |
1745 | |
1746 | list_for_each_entry(cn, &clk_notifier_list, node) { |
1747 | if (cn->clk->core == core) { |
1748 | cnd.clk = cn->clk; |
1749 | ret = srcu_notifier_call_chain(nh: &cn->notifier_head, val: msg, |
1750 | v: &cnd); |
1751 | if (ret & NOTIFY_STOP_MASK) |
1752 | return ret; |
1753 | } |
1754 | } |
1755 | |
1756 | return ret; |
1757 | } |
1758 | |
1759 | /** |
1760 | * __clk_recalc_accuracies |
1761 | * @core: first clk in the subtree |
1762 | * |
1763 | * Walks the subtree of clks starting with clk and recalculates accuracies as |
1764 | * it goes. Note that if a clk does not implement the .recalc_accuracy |
1765 | * callback then it is assumed that the clock will take on the accuracy of its |
1766 | * parent. |
1767 | */ |
1768 | static void __clk_recalc_accuracies(struct clk_core *core) |
1769 | { |
1770 | unsigned long parent_accuracy = 0; |
1771 | struct clk_core *child; |
1772 | |
1773 | lockdep_assert_held(&prepare_lock); |
1774 | |
1775 | if (core->parent) |
1776 | parent_accuracy = core->parent->accuracy; |
1777 | |
1778 | if (core->ops->recalc_accuracy) |
1779 | core->accuracy = core->ops->recalc_accuracy(core->hw, |
1780 | parent_accuracy); |
1781 | else |
1782 | core->accuracy = parent_accuracy; |
1783 | |
1784 | hlist_for_each_entry(child, &core->children, child_node) |
1785 | __clk_recalc_accuracies(core: child); |
1786 | } |
1787 | |
1788 | static long clk_core_get_accuracy_recalc(struct clk_core *core) |
1789 | { |
1790 | if (core && (core->flags & CLK_GET_ACCURACY_NOCACHE)) |
1791 | __clk_recalc_accuracies(core); |
1792 | |
1793 | return clk_core_get_accuracy_no_lock(core); |
1794 | } |
1795 | |
1796 | /** |
1797 | * clk_get_accuracy - return the accuracy of clk |
1798 | * @clk: the clk whose accuracy is being returned |
1799 | * |
1800 | * Simply returns the cached accuracy of the clk, unless |
1801 | * CLK_GET_ACCURACY_NOCACHE flag is set, which means a recalc_rate will be |
1802 | * issued. |
1803 | * If clk is NULL then returns 0. |
1804 | */ |
1805 | long clk_get_accuracy(struct clk *clk) |
1806 | { |
1807 | long accuracy; |
1808 | |
1809 | if (!clk) |
1810 | return 0; |
1811 | |
1812 | clk_prepare_lock(); |
1813 | accuracy = clk_core_get_accuracy_recalc(core: clk->core); |
1814 | clk_prepare_unlock(); |
1815 | |
1816 | return accuracy; |
1817 | } |
1818 | EXPORT_SYMBOL_GPL(clk_get_accuracy); |
1819 | |
1820 | static unsigned long clk_recalc(struct clk_core *core, |
1821 | unsigned long parent_rate) |
1822 | { |
1823 | unsigned long rate = parent_rate; |
1824 | |
1825 | if (core->ops->recalc_rate && !clk_pm_runtime_get(core)) { |
1826 | rate = core->ops->recalc_rate(core->hw, parent_rate); |
1827 | clk_pm_runtime_put(core); |
1828 | } |
1829 | return rate; |
1830 | } |
1831 | |
1832 | /** |
1833 | * __clk_recalc_rates |
1834 | * @core: first clk in the subtree |
1835 | * @update_req: Whether req_rate should be updated with the new rate |
1836 | * @msg: notification type (see include/linux/clk.h) |
1837 | * |
1838 | * Walks the subtree of clks starting with clk and recalculates rates as it |
1839 | * goes. Note that if a clk does not implement the .recalc_rate callback then |
1840 | * it is assumed that the clock will take on the rate of its parent. |
1841 | * |
1842 | * clk_recalc_rates also propagates the POST_RATE_CHANGE notification, |
1843 | * if necessary. |
1844 | */ |
1845 | static void __clk_recalc_rates(struct clk_core *core, bool update_req, |
1846 | unsigned long msg) |
1847 | { |
1848 | unsigned long old_rate; |
1849 | unsigned long parent_rate = 0; |
1850 | struct clk_core *child; |
1851 | |
1852 | lockdep_assert_held(&prepare_lock); |
1853 | |
1854 | old_rate = core->rate; |
1855 | |
1856 | if (core->parent) |
1857 | parent_rate = core->parent->rate; |
1858 | |
1859 | core->rate = clk_recalc(core, parent_rate); |
1860 | if (update_req) |
1861 | core->req_rate = core->rate; |
1862 | |
1863 | /* |
1864 | * ignore NOTIFY_STOP and NOTIFY_BAD return values for POST_RATE_CHANGE |
1865 | * & ABORT_RATE_CHANGE notifiers |
1866 | */ |
1867 | if (core->notifier_count && msg) |
1868 | __clk_notify(core, msg, old_rate, new_rate: core->rate); |
1869 | |
1870 | hlist_for_each_entry(child, &core->children, child_node) |
1871 | __clk_recalc_rates(core: child, update_req, msg); |
1872 | } |
1873 | |
1874 | static unsigned long clk_core_get_rate_recalc(struct clk_core *core) |
1875 | { |
1876 | if (core && (core->flags & CLK_GET_RATE_NOCACHE)) |
1877 | __clk_recalc_rates(core, update_req: false, msg: 0); |
1878 | |
1879 | return clk_core_get_rate_nolock(core); |
1880 | } |
1881 | |
1882 | /** |
1883 | * clk_get_rate - return the rate of clk |
1884 | * @clk: the clk whose rate is being returned |
1885 | * |
1886 | * Simply returns the cached rate of the clk, unless CLK_GET_RATE_NOCACHE flag |
1887 | * is set, which means a recalc_rate will be issued. Can be called regardless of |
1888 | * the clock enabledness. If clk is NULL, or if an error occurred, then returns |
1889 | * 0. |
1890 | */ |
1891 | unsigned long clk_get_rate(struct clk *clk) |
1892 | { |
1893 | unsigned long rate; |
1894 | |
1895 | if (!clk) |
1896 | return 0; |
1897 | |
1898 | clk_prepare_lock(); |
1899 | rate = clk_core_get_rate_recalc(core: clk->core); |
1900 | clk_prepare_unlock(); |
1901 | |
1902 | return rate; |
1903 | } |
1904 | EXPORT_SYMBOL_GPL(clk_get_rate); |
1905 | |
1906 | static int clk_fetch_parent_index(struct clk_core *core, |
1907 | struct clk_core *parent) |
1908 | { |
1909 | int i; |
1910 | |
1911 | if (!parent) |
1912 | return -EINVAL; |
1913 | |
1914 | for (i = 0; i < core->num_parents; i++) { |
1915 | /* Found it first try! */ |
1916 | if (core->parents[i].core == parent) |
1917 | return i; |
1918 | |
1919 | /* Something else is here, so keep looking */ |
1920 | if (core->parents[i].core) |
1921 | continue; |
1922 | |
1923 | /* Maybe core hasn't been cached but the hw is all we know? */ |
1924 | if (core->parents[i].hw) { |
1925 | if (core->parents[i].hw == parent->hw) |
1926 | break; |
1927 | |
1928 | /* Didn't match, but we're expecting a clk_hw */ |
1929 | continue; |
1930 | } |
1931 | |
1932 | /* Maybe it hasn't been cached (clk_set_parent() path) */ |
1933 | if (parent == clk_core_get(core, p_index: i)) |
1934 | break; |
1935 | |
1936 | /* Fallback to comparing globally unique names */ |
1937 | if (core->parents[i].name && |
1938 | !strcmp(parent->name, core->parents[i].name)) |
1939 | break; |
1940 | } |
1941 | |
1942 | if (i == core->num_parents) |
1943 | return -EINVAL; |
1944 | |
1945 | core->parents[i].core = parent; |
1946 | return i; |
1947 | } |
1948 | |
1949 | /** |
1950 | * clk_hw_get_parent_index - return the index of the parent clock |
1951 | * @hw: clk_hw associated with the clk being consumed |
1952 | * |
1953 | * Fetches and returns the index of parent clock. Returns -EINVAL if the given |
1954 | * clock does not have a current parent. |
1955 | */ |
1956 | int clk_hw_get_parent_index(struct clk_hw *hw) |
1957 | { |
1958 | struct clk_hw *parent = clk_hw_get_parent(hw); |
1959 | |
1960 | if (WARN_ON(parent == NULL)) |
1961 | return -EINVAL; |
1962 | |
1963 | return clk_fetch_parent_index(core: hw->core, parent: parent->core); |
1964 | } |
1965 | EXPORT_SYMBOL_GPL(clk_hw_get_parent_index); |
1966 | |
1967 | /* |
1968 | * Update the orphan status of @core and all its children. |
1969 | */ |
1970 | static void clk_core_update_orphan_status(struct clk_core *core, bool is_orphan) |
1971 | { |
1972 | struct clk_core *child; |
1973 | |
1974 | core->orphan = is_orphan; |
1975 | |
1976 | hlist_for_each_entry(child, &core->children, child_node) |
1977 | clk_core_update_orphan_status(core: child, is_orphan); |
1978 | } |
1979 | |
1980 | static void clk_reparent(struct clk_core *core, struct clk_core *new_parent) |
1981 | { |
1982 | bool was_orphan = core->orphan; |
1983 | |
1984 | hlist_del(n: &core->child_node); |
1985 | |
1986 | if (new_parent) { |
1987 | bool becomes_orphan = new_parent->orphan; |
1988 | |
1989 | /* avoid duplicate POST_RATE_CHANGE notifications */ |
1990 | if (new_parent->new_child == core) |
1991 | new_parent->new_child = NULL; |
1992 | |
1993 | hlist_add_head(n: &core->child_node, h: &new_parent->children); |
1994 | |
1995 | if (was_orphan != becomes_orphan) |
1996 | clk_core_update_orphan_status(core, is_orphan: becomes_orphan); |
1997 | } else { |
1998 | hlist_add_head(n: &core->child_node, h: &clk_orphan_list); |
1999 | if (!was_orphan) |
2000 | clk_core_update_orphan_status(core, is_orphan: true); |
2001 | } |
2002 | |
2003 | core->parent = new_parent; |
2004 | } |
2005 | |
2006 | static struct clk_core *__clk_set_parent_before(struct clk_core *core, |
2007 | struct clk_core *parent) |
2008 | { |
2009 | unsigned long flags; |
2010 | struct clk_core *old_parent = core->parent; |
2011 | |
2012 | /* |
2013 | * 1. enable parents for CLK_OPS_PARENT_ENABLE clock |
2014 | * |
2015 | * 2. Migrate prepare state between parents and prevent race with |
2016 | * clk_enable(). |
2017 | * |
2018 | * If the clock is not prepared, then a race with |
2019 | * clk_enable/disable() is impossible since we already have the |
2020 | * prepare lock (future calls to clk_enable() need to be preceded by |
2021 | * a clk_prepare()). |
2022 | * |
2023 | * If the clock is prepared, migrate the prepared state to the new |
2024 | * parent and also protect against a race with clk_enable() by |
2025 | * forcing the clock and the new parent on. This ensures that all |
2026 | * future calls to clk_enable() are practically NOPs with respect to |
2027 | * hardware and software states. |
2028 | * |
2029 | * See also: Comment for clk_set_parent() below. |
2030 | */ |
2031 | |
2032 | /* enable old_parent & parent if CLK_OPS_PARENT_ENABLE is set */ |
2033 | if (core->flags & CLK_OPS_PARENT_ENABLE) { |
2034 | clk_core_prepare_enable(core: old_parent); |
2035 | clk_core_prepare_enable(core: parent); |
2036 | } |
2037 | |
2038 | /* migrate prepare count if > 0 */ |
2039 | if (core->prepare_count) { |
2040 | clk_core_prepare_enable(core: parent); |
2041 | clk_core_enable_lock(core); |
2042 | } |
2043 | |
2044 | /* update the clk tree topology */ |
2045 | flags = clk_enable_lock(); |
2046 | clk_reparent(core, new_parent: parent); |
2047 | clk_enable_unlock(flags); |
2048 | |
2049 | return old_parent; |
2050 | } |
2051 | |
2052 | static void __clk_set_parent_after(struct clk_core *core, |
2053 | struct clk_core *parent, |
2054 | struct clk_core *old_parent) |
2055 | { |
2056 | /* |
2057 | * Finish the migration of prepare state and undo the changes done |
2058 | * for preventing a race with clk_enable(). |
2059 | */ |
2060 | if (core->prepare_count) { |
2061 | clk_core_disable_lock(core); |
2062 | clk_core_disable_unprepare(core: old_parent); |
2063 | } |
2064 | |
2065 | /* re-balance ref counting if CLK_OPS_PARENT_ENABLE is set */ |
2066 | if (core->flags & CLK_OPS_PARENT_ENABLE) { |
2067 | clk_core_disable_unprepare(core: parent); |
2068 | clk_core_disable_unprepare(core: old_parent); |
2069 | } |
2070 | } |
2071 | |
2072 | static int __clk_set_parent(struct clk_core *core, struct clk_core *parent, |
2073 | u8 p_index) |
2074 | { |
2075 | unsigned long flags; |
2076 | int ret = 0; |
2077 | struct clk_core *old_parent; |
2078 | |
2079 | old_parent = __clk_set_parent_before(core, parent); |
2080 | |
2081 | trace_clk_set_parent(core, parent); |
2082 | |
2083 | /* change clock input source */ |
2084 | if (parent && core->ops->set_parent) |
2085 | ret = core->ops->set_parent(core->hw, p_index); |
2086 | |
2087 | trace_clk_set_parent_complete(core, parent); |
2088 | |
2089 | if (ret) { |
2090 | flags = clk_enable_lock(); |
2091 | clk_reparent(core, new_parent: old_parent); |
2092 | clk_enable_unlock(flags); |
2093 | |
2094 | __clk_set_parent_after(core, parent: old_parent, old_parent: parent); |
2095 | |
2096 | return ret; |
2097 | } |
2098 | |
2099 | __clk_set_parent_after(core, parent, old_parent); |
2100 | |
2101 | return 0; |
2102 | } |
2103 | |
2104 | /** |
2105 | * __clk_speculate_rates |
2106 | * @core: first clk in the subtree |
2107 | * @parent_rate: the "future" rate of clk's parent |
2108 | * |
2109 | * Walks the subtree of clks starting with clk, speculating rates as it |
2110 | * goes and firing off PRE_RATE_CHANGE notifications as necessary. |
2111 | * |
2112 | * Unlike clk_recalc_rates, clk_speculate_rates exists only for sending |
2113 | * pre-rate change notifications and returns early if no clks in the |
2114 | * subtree have subscribed to the notifications. Note that if a clk does not |
2115 | * implement the .recalc_rate callback then it is assumed that the clock will |
2116 | * take on the rate of its parent. |
2117 | */ |
2118 | static int __clk_speculate_rates(struct clk_core *core, |
2119 | unsigned long parent_rate) |
2120 | { |
2121 | struct clk_core *child; |
2122 | unsigned long new_rate; |
2123 | int ret = NOTIFY_DONE; |
2124 | |
2125 | lockdep_assert_held(&prepare_lock); |
2126 | |
2127 | new_rate = clk_recalc(core, parent_rate); |
2128 | |
2129 | /* abort rate change if a driver returns NOTIFY_BAD or NOTIFY_STOP */ |
2130 | if (core->notifier_count) |
2131 | ret = __clk_notify(core, PRE_RATE_CHANGE, old_rate: core->rate, new_rate); |
2132 | |
2133 | if (ret & NOTIFY_STOP_MASK) { |
2134 | pr_debug("%s: clk notifier callback for clock %s aborted with error %d\n" , |
2135 | __func__, core->name, ret); |
2136 | goto out; |
2137 | } |
2138 | |
2139 | hlist_for_each_entry(child, &core->children, child_node) { |
2140 | ret = __clk_speculate_rates(core: child, parent_rate: new_rate); |
2141 | if (ret & NOTIFY_STOP_MASK) |
2142 | break; |
2143 | } |
2144 | |
2145 | out: |
2146 | return ret; |
2147 | } |
2148 | |
2149 | static void clk_calc_subtree(struct clk_core *core, unsigned long new_rate, |
2150 | struct clk_core *new_parent, u8 p_index) |
2151 | { |
2152 | struct clk_core *child; |
2153 | |
2154 | core->new_rate = new_rate; |
2155 | core->new_parent = new_parent; |
2156 | core->new_parent_index = p_index; |
2157 | /* include clk in new parent's PRE_RATE_CHANGE notifications */ |
2158 | core->new_child = NULL; |
2159 | if (new_parent && new_parent != core->parent) |
2160 | new_parent->new_child = core; |
2161 | |
2162 | hlist_for_each_entry(child, &core->children, child_node) { |
2163 | child->new_rate = clk_recalc(core: child, parent_rate: new_rate); |
2164 | clk_calc_subtree(core: child, new_rate: child->new_rate, NULL, p_index: 0); |
2165 | } |
2166 | } |
2167 | |
2168 | /* |
2169 | * calculate the new rates returning the topmost clock that has to be |
2170 | * changed. |
2171 | */ |
2172 | static struct clk_core *clk_calc_new_rates(struct clk_core *core, |
2173 | unsigned long rate) |
2174 | { |
2175 | struct clk_core *top = core; |
2176 | struct clk_core *old_parent, *parent; |
2177 | unsigned long best_parent_rate = 0; |
2178 | unsigned long new_rate; |
2179 | unsigned long min_rate; |
2180 | unsigned long max_rate; |
2181 | int p_index = 0; |
2182 | long ret; |
2183 | |
2184 | /* sanity */ |
2185 | if (IS_ERR_OR_NULL(ptr: core)) |
2186 | return NULL; |
2187 | |
2188 | /* save parent rate, if it exists */ |
2189 | parent = old_parent = core->parent; |
2190 | if (parent) |
2191 | best_parent_rate = parent->rate; |
2192 | |
2193 | clk_core_get_boundaries(core, min_rate: &min_rate, max_rate: &max_rate); |
2194 | |
2195 | /* find the closest rate and parent clk/rate */ |
2196 | if (clk_core_can_round(core)) { |
2197 | struct clk_rate_request req; |
2198 | |
2199 | clk_core_init_rate_req(core, req: &req, rate); |
2200 | |
2201 | trace_clk_rate_request_start(req: &req); |
2202 | |
2203 | ret = clk_core_determine_round_nolock(core, req: &req); |
2204 | if (ret < 0) |
2205 | return NULL; |
2206 | |
2207 | trace_clk_rate_request_done(req: &req); |
2208 | |
2209 | best_parent_rate = req.best_parent_rate; |
2210 | new_rate = req.rate; |
2211 | parent = req.best_parent_hw ? req.best_parent_hw->core : NULL; |
2212 | |
2213 | if (new_rate < min_rate || new_rate > max_rate) |
2214 | return NULL; |
2215 | } else if (!parent || !(core->flags & CLK_SET_RATE_PARENT)) { |
2216 | /* pass-through clock without adjustable parent */ |
2217 | core->new_rate = core->rate; |
2218 | return NULL; |
2219 | } else { |
2220 | /* pass-through clock with adjustable parent */ |
2221 | top = clk_calc_new_rates(core: parent, rate); |
2222 | new_rate = parent->new_rate; |
2223 | goto out; |
2224 | } |
2225 | |
2226 | /* some clocks must be gated to change parent */ |
2227 | if (parent != old_parent && |
2228 | (core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) { |
2229 | pr_debug("%s: %s not gated but wants to reparent\n" , |
2230 | __func__, core->name); |
2231 | return NULL; |
2232 | } |
2233 | |
2234 | /* try finding the new parent index */ |
2235 | if (parent && core->num_parents > 1) { |
2236 | p_index = clk_fetch_parent_index(core, parent); |
2237 | if (p_index < 0) { |
2238 | pr_debug("%s: clk %s can not be parent of clk %s\n" , |
2239 | __func__, parent->name, core->name); |
2240 | return NULL; |
2241 | } |
2242 | } |
2243 | |
2244 | if ((core->flags & CLK_SET_RATE_PARENT) && parent && |
2245 | best_parent_rate != parent->rate) |
2246 | top = clk_calc_new_rates(core: parent, rate: best_parent_rate); |
2247 | |
2248 | out: |
2249 | clk_calc_subtree(core, new_rate, new_parent: parent, p_index); |
2250 | |
2251 | return top; |
2252 | } |
2253 | |
2254 | /* |
2255 | * Notify about rate changes in a subtree. Always walk down the whole tree |
2256 | * so that in case of an error we can walk down the whole tree again and |
2257 | * abort the change. |
2258 | */ |
2259 | static struct clk_core *clk_propagate_rate_change(struct clk_core *core, |
2260 | unsigned long event) |
2261 | { |
2262 | struct clk_core *child, *tmp_clk, *fail_clk = NULL; |
2263 | int ret = NOTIFY_DONE; |
2264 | |
2265 | if (core->rate == core->new_rate) |
2266 | return NULL; |
2267 | |
2268 | if (core->notifier_count) { |
2269 | ret = __clk_notify(core, msg: event, old_rate: core->rate, new_rate: core->new_rate); |
2270 | if (ret & NOTIFY_STOP_MASK) |
2271 | fail_clk = core; |
2272 | } |
2273 | |
2274 | hlist_for_each_entry(child, &core->children, child_node) { |
2275 | /* Skip children who will be reparented to another clock */ |
2276 | if (child->new_parent && child->new_parent != core) |
2277 | continue; |
2278 | tmp_clk = clk_propagate_rate_change(core: child, event); |
2279 | if (tmp_clk) |
2280 | fail_clk = tmp_clk; |
2281 | } |
2282 | |
2283 | /* handle the new child who might not be in core->children yet */ |
2284 | if (core->new_child) { |
2285 | tmp_clk = clk_propagate_rate_change(core: core->new_child, event); |
2286 | if (tmp_clk) |
2287 | fail_clk = tmp_clk; |
2288 | } |
2289 | |
2290 | return fail_clk; |
2291 | } |
2292 | |
2293 | /* |
2294 | * walk down a subtree and set the new rates notifying the rate |
2295 | * change on the way |
2296 | */ |
2297 | static void clk_change_rate(struct clk_core *core) |
2298 | { |
2299 | struct clk_core *child; |
2300 | struct hlist_node *tmp; |
2301 | unsigned long old_rate; |
2302 | unsigned long best_parent_rate = 0; |
2303 | bool skip_set_rate = false; |
2304 | struct clk_core *old_parent; |
2305 | struct clk_core *parent = NULL; |
2306 | |
2307 | old_rate = core->rate; |
2308 | |
2309 | if (core->new_parent) { |
2310 | parent = core->new_parent; |
2311 | best_parent_rate = core->new_parent->rate; |
2312 | } else if (core->parent) { |
2313 | parent = core->parent; |
2314 | best_parent_rate = core->parent->rate; |
2315 | } |
2316 | |
2317 | if (clk_pm_runtime_get(core)) |
2318 | return; |
2319 | |
2320 | if (core->flags & CLK_SET_RATE_UNGATE) { |
2321 | clk_core_prepare(core); |
2322 | clk_core_enable_lock(core); |
2323 | } |
2324 | |
2325 | if (core->new_parent && core->new_parent != core->parent) { |
2326 | old_parent = __clk_set_parent_before(core, parent: core->new_parent); |
2327 | trace_clk_set_parent(core, parent: core->new_parent); |
2328 | |
2329 | if (core->ops->set_rate_and_parent) { |
2330 | skip_set_rate = true; |
2331 | core->ops->set_rate_and_parent(core->hw, core->new_rate, |
2332 | best_parent_rate, |
2333 | core->new_parent_index); |
2334 | } else if (core->ops->set_parent) { |
2335 | core->ops->set_parent(core->hw, core->new_parent_index); |
2336 | } |
2337 | |
2338 | trace_clk_set_parent_complete(core, parent: core->new_parent); |
2339 | __clk_set_parent_after(core, parent: core->new_parent, old_parent); |
2340 | } |
2341 | |
2342 | if (core->flags & CLK_OPS_PARENT_ENABLE) |
2343 | clk_core_prepare_enable(core: parent); |
2344 | |
2345 | trace_clk_set_rate(core, rate: core->new_rate); |
2346 | |
2347 | if (!skip_set_rate && core->ops->set_rate) |
2348 | core->ops->set_rate(core->hw, core->new_rate, best_parent_rate); |
2349 | |
2350 | trace_clk_set_rate_complete(core, rate: core->new_rate); |
2351 | |
2352 | core->rate = clk_recalc(core, parent_rate: best_parent_rate); |
2353 | |
2354 | if (core->flags & CLK_SET_RATE_UNGATE) { |
2355 | clk_core_disable_lock(core); |
2356 | clk_core_unprepare(core); |
2357 | } |
2358 | |
2359 | if (core->flags & CLK_OPS_PARENT_ENABLE) |
2360 | clk_core_disable_unprepare(core: parent); |
2361 | |
2362 | if (core->notifier_count && old_rate != core->rate) |
2363 | __clk_notify(core, POST_RATE_CHANGE, old_rate, new_rate: core->rate); |
2364 | |
2365 | if (core->flags & CLK_RECALC_NEW_RATES) |
2366 | (void)clk_calc_new_rates(core, rate: core->new_rate); |
2367 | |
2368 | /* |
2369 | * Use safe iteration, as change_rate can actually swap parents |
2370 | * for certain clock types. |
2371 | */ |
2372 | hlist_for_each_entry_safe(child, tmp, &core->children, child_node) { |
2373 | /* Skip children who will be reparented to another clock */ |
2374 | if (child->new_parent && child->new_parent != core) |
2375 | continue; |
2376 | clk_change_rate(core: child); |
2377 | } |
2378 | |
2379 | /* handle the new child who might not be in core->children yet */ |
2380 | if (core->new_child) |
2381 | clk_change_rate(core: core->new_child); |
2382 | |
2383 | clk_pm_runtime_put(core); |
2384 | } |
2385 | |
2386 | static unsigned long clk_core_req_round_rate_nolock(struct clk_core *core, |
2387 | unsigned long req_rate) |
2388 | { |
2389 | int ret, cnt; |
2390 | struct clk_rate_request req; |
2391 | |
2392 | lockdep_assert_held(&prepare_lock); |
2393 | |
2394 | if (!core) |
2395 | return 0; |
2396 | |
2397 | /* simulate what the rate would be if it could be freely set */ |
2398 | cnt = clk_core_rate_nuke_protect(core); |
2399 | if (cnt < 0) |
2400 | return cnt; |
2401 | |
2402 | clk_core_init_rate_req(core, req: &req, rate: req_rate); |
2403 | |
2404 | trace_clk_rate_request_start(req: &req); |
2405 | |
2406 | ret = clk_core_round_rate_nolock(core, req: &req); |
2407 | |
2408 | trace_clk_rate_request_done(req: &req); |
2409 | |
2410 | /* restore the protection */ |
2411 | clk_core_rate_restore_protect(core, count: cnt); |
2412 | |
2413 | return ret ? 0 : req.rate; |
2414 | } |
2415 | |
2416 | static int clk_core_set_rate_nolock(struct clk_core *core, |
2417 | unsigned long req_rate) |
2418 | { |
2419 | struct clk_core *top, *fail_clk; |
2420 | unsigned long rate; |
2421 | int ret; |
2422 | |
2423 | if (!core) |
2424 | return 0; |
2425 | |
2426 | rate = clk_core_req_round_rate_nolock(core, req_rate); |
2427 | |
2428 | /* bail early if nothing to do */ |
2429 | if (rate == clk_core_get_rate_nolock(core)) |
2430 | return 0; |
2431 | |
2432 | /* fail on a direct rate set of a protected provider */ |
2433 | if (clk_core_rate_is_protected(core)) |
2434 | return -EBUSY; |
2435 | |
2436 | /* calculate new rates and get the topmost changed clock */ |
2437 | top = clk_calc_new_rates(core, rate: req_rate); |
2438 | if (!top) |
2439 | return -EINVAL; |
2440 | |
2441 | ret = clk_pm_runtime_get(core); |
2442 | if (ret) |
2443 | return ret; |
2444 | |
2445 | /* notify that we are about to change rates */ |
2446 | fail_clk = clk_propagate_rate_change(core: top, PRE_RATE_CHANGE); |
2447 | if (fail_clk) { |
2448 | pr_debug("%s: failed to set %s rate\n" , __func__, |
2449 | fail_clk->name); |
2450 | clk_propagate_rate_change(core: top, ABORT_RATE_CHANGE); |
2451 | ret = -EBUSY; |
2452 | goto err; |
2453 | } |
2454 | |
2455 | /* change the rates */ |
2456 | clk_change_rate(core: top); |
2457 | |
2458 | core->req_rate = req_rate; |
2459 | err: |
2460 | clk_pm_runtime_put(core); |
2461 | |
2462 | return ret; |
2463 | } |
2464 | |
2465 | /** |
2466 | * clk_set_rate - specify a new rate for clk |
2467 | * @clk: the clk whose rate is being changed |
2468 | * @rate: the new rate for clk |
2469 | * |
2470 | * In the simplest case clk_set_rate will only adjust the rate of clk. |
2471 | * |
2472 | * Setting the CLK_SET_RATE_PARENT flag allows the rate change operation to |
2473 | * propagate up to clk's parent; whether or not this happens depends on the |
2474 | * outcome of clk's .round_rate implementation. If *parent_rate is unchanged |
2475 | * after calling .round_rate then upstream parent propagation is ignored. If |
2476 | * *parent_rate comes back with a new rate for clk's parent then we propagate |
2477 | * up to clk's parent and set its rate. Upward propagation will continue |
2478 | * until either a clk does not support the CLK_SET_RATE_PARENT flag or |
2479 | * .round_rate stops requesting changes to clk's parent_rate. |
2480 | * |
2481 | * Rate changes are accomplished via tree traversal that also recalculates the |
2482 | * rates for the clocks and fires off POST_RATE_CHANGE notifiers. |
2483 | * |
2484 | * Returns 0 on success, -EERROR otherwise. |
2485 | */ |
2486 | int clk_set_rate(struct clk *clk, unsigned long rate) |
2487 | { |
2488 | int ret; |
2489 | |
2490 | if (!clk) |
2491 | return 0; |
2492 | |
2493 | /* prevent racing with updates to the clock topology */ |
2494 | clk_prepare_lock(); |
2495 | |
2496 | if (clk->exclusive_count) |
2497 | clk_core_rate_unprotect(core: clk->core); |
2498 | |
2499 | ret = clk_core_set_rate_nolock(core: clk->core, req_rate: rate); |
2500 | |
2501 | if (clk->exclusive_count) |
2502 | clk_core_rate_protect(core: clk->core); |
2503 | |
2504 | clk_prepare_unlock(); |
2505 | |
2506 | return ret; |
2507 | } |
2508 | EXPORT_SYMBOL_GPL(clk_set_rate); |
2509 | |
2510 | /** |
2511 | * clk_set_rate_exclusive - specify a new rate and get exclusive control |
2512 | * @clk: the clk whose rate is being changed |
2513 | * @rate: the new rate for clk |
2514 | * |
2515 | * This is a combination of clk_set_rate() and clk_rate_exclusive_get() |
2516 | * within a critical section |
2517 | * |
2518 | * This can be used initially to ensure that at least 1 consumer is |
2519 | * satisfied when several consumers are competing for exclusivity over the |
2520 | * same clock provider. |
2521 | * |
2522 | * The exclusivity is not applied if setting the rate failed. |
2523 | * |
2524 | * Calls to clk_rate_exclusive_get() should be balanced with calls to |
2525 | * clk_rate_exclusive_put(). |
2526 | * |
2527 | * Returns 0 on success, -EERROR otherwise. |
2528 | */ |
2529 | int clk_set_rate_exclusive(struct clk *clk, unsigned long rate) |
2530 | { |
2531 | int ret; |
2532 | |
2533 | if (!clk) |
2534 | return 0; |
2535 | |
2536 | /* prevent racing with updates to the clock topology */ |
2537 | clk_prepare_lock(); |
2538 | |
2539 | /* |
2540 | * The temporary protection removal is not here, on purpose |
2541 | * This function is meant to be used instead of clk_rate_protect, |
2542 | * so before the consumer code path protect the clock provider |
2543 | */ |
2544 | |
2545 | ret = clk_core_set_rate_nolock(core: clk->core, req_rate: rate); |
2546 | if (!ret) { |
2547 | clk_core_rate_protect(core: clk->core); |
2548 | clk->exclusive_count++; |
2549 | } |
2550 | |
2551 | clk_prepare_unlock(); |
2552 | |
2553 | return ret; |
2554 | } |
2555 | EXPORT_SYMBOL_GPL(clk_set_rate_exclusive); |
2556 | |
2557 | static int clk_set_rate_range_nolock(struct clk *clk, |
2558 | unsigned long min, |
2559 | unsigned long max) |
2560 | { |
2561 | int ret = 0; |
2562 | unsigned long old_min, old_max, rate; |
2563 | |
2564 | lockdep_assert_held(&prepare_lock); |
2565 | |
2566 | if (!clk) |
2567 | return 0; |
2568 | |
2569 | trace_clk_set_rate_range(core: clk->core, min, max); |
2570 | |
2571 | if (min > max) { |
2572 | pr_err("%s: clk %s dev %s con %s: invalid range [%lu, %lu]\n" , |
2573 | __func__, clk->core->name, clk->dev_id, clk->con_id, |
2574 | min, max); |
2575 | return -EINVAL; |
2576 | } |
2577 | |
2578 | if (clk->exclusive_count) |
2579 | clk_core_rate_unprotect(core: clk->core); |
2580 | |
2581 | /* Save the current values in case we need to rollback the change */ |
2582 | old_min = clk->min_rate; |
2583 | old_max = clk->max_rate; |
2584 | clk->min_rate = min; |
2585 | clk->max_rate = max; |
2586 | |
2587 | if (!clk_core_check_boundaries(core: clk->core, min_rate: min, max_rate: max)) { |
2588 | ret = -EINVAL; |
2589 | goto out; |
2590 | } |
2591 | |
2592 | rate = clk->core->req_rate; |
2593 | if (clk->core->flags & CLK_GET_RATE_NOCACHE) |
2594 | rate = clk_core_get_rate_recalc(core: clk->core); |
2595 | |
2596 | /* |
2597 | * Since the boundaries have been changed, let's give the |
2598 | * opportunity to the provider to adjust the clock rate based on |
2599 | * the new boundaries. |
2600 | * |
2601 | * We also need to handle the case where the clock is currently |
2602 | * outside of the boundaries. Clamping the last requested rate |
2603 | * to the current minimum and maximum will also handle this. |
2604 | * |
2605 | * FIXME: |
2606 | * There is a catch. It may fail for the usual reason (clock |
2607 | * broken, clock protected, etc) but also because: |
2608 | * - round_rate() was not favorable and fell on the wrong |
2609 | * side of the boundary |
2610 | * - the determine_rate() callback does not really check for |
2611 | * this corner case when determining the rate |
2612 | */ |
2613 | rate = clamp(rate, min, max); |
2614 | ret = clk_core_set_rate_nolock(core: clk->core, req_rate: rate); |
2615 | if (ret) { |
2616 | /* rollback the changes */ |
2617 | clk->min_rate = old_min; |
2618 | clk->max_rate = old_max; |
2619 | } |
2620 | |
2621 | out: |
2622 | if (clk->exclusive_count) |
2623 | clk_core_rate_protect(core: clk->core); |
2624 | |
2625 | return ret; |
2626 | } |
2627 | |
2628 | /** |
2629 | * clk_set_rate_range - set a rate range for a clock source |
2630 | * @clk: clock source |
2631 | * @min: desired minimum clock rate in Hz, inclusive |
2632 | * @max: desired maximum clock rate in Hz, inclusive |
2633 | * |
2634 | * Return: 0 for success or negative errno on failure. |
2635 | */ |
2636 | int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max) |
2637 | { |
2638 | int ret; |
2639 | |
2640 | if (!clk) |
2641 | return 0; |
2642 | |
2643 | clk_prepare_lock(); |
2644 | |
2645 | ret = clk_set_rate_range_nolock(clk, min, max); |
2646 | |
2647 | clk_prepare_unlock(); |
2648 | |
2649 | return ret; |
2650 | } |
2651 | EXPORT_SYMBOL_GPL(clk_set_rate_range); |
2652 | |
2653 | /** |
2654 | * clk_set_min_rate - set a minimum clock rate for a clock source |
2655 | * @clk: clock source |
2656 | * @rate: desired minimum clock rate in Hz, inclusive |
2657 | * |
2658 | * Returns success (0) or negative errno. |
2659 | */ |
2660 | int clk_set_min_rate(struct clk *clk, unsigned long rate) |
2661 | { |
2662 | if (!clk) |
2663 | return 0; |
2664 | |
2665 | trace_clk_set_min_rate(core: clk->core, rate); |
2666 | |
2667 | return clk_set_rate_range(clk, rate, clk->max_rate); |
2668 | } |
2669 | EXPORT_SYMBOL_GPL(clk_set_min_rate); |
2670 | |
2671 | /** |
2672 | * clk_set_max_rate - set a maximum clock rate for a clock source |
2673 | * @clk: clock source |
2674 | * @rate: desired maximum clock rate in Hz, inclusive |
2675 | * |
2676 | * Returns success (0) or negative errno. |
2677 | */ |
2678 | int clk_set_max_rate(struct clk *clk, unsigned long rate) |
2679 | { |
2680 | if (!clk) |
2681 | return 0; |
2682 | |
2683 | trace_clk_set_max_rate(core: clk->core, rate); |
2684 | |
2685 | return clk_set_rate_range(clk, clk->min_rate, rate); |
2686 | } |
2687 | EXPORT_SYMBOL_GPL(clk_set_max_rate); |
2688 | |
2689 | /** |
2690 | * clk_get_parent - return the parent of a clk |
2691 | * @clk: the clk whose parent gets returned |
2692 | * |
2693 | * Simply returns clk->parent. Returns NULL if clk is NULL. |
2694 | */ |
2695 | struct clk *clk_get_parent(struct clk *clk) |
2696 | { |
2697 | struct clk *parent; |
2698 | |
2699 | if (!clk) |
2700 | return NULL; |
2701 | |
2702 | clk_prepare_lock(); |
2703 | /* TODO: Create a per-user clk and change callers to call clk_put */ |
2704 | parent = !clk->core->parent ? NULL : clk->core->parent->hw->clk; |
2705 | clk_prepare_unlock(); |
2706 | |
2707 | return parent; |
2708 | } |
2709 | EXPORT_SYMBOL_GPL(clk_get_parent); |
2710 | |
2711 | static struct clk_core *__clk_init_parent(struct clk_core *core) |
2712 | { |
2713 | u8 index = 0; |
2714 | |
2715 | if (core->num_parents > 1 && core->ops->get_parent) |
2716 | index = core->ops->get_parent(core->hw); |
2717 | |
2718 | return clk_core_get_parent_by_index(core, index); |
2719 | } |
2720 | |
2721 | static void clk_core_reparent(struct clk_core *core, |
2722 | struct clk_core *new_parent) |
2723 | { |
2724 | clk_reparent(core, new_parent); |
2725 | __clk_recalc_accuracies(core); |
2726 | __clk_recalc_rates(core, update_req: true, POST_RATE_CHANGE); |
2727 | } |
2728 | |
2729 | void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent) |
2730 | { |
2731 | if (!hw) |
2732 | return; |
2733 | |
2734 | clk_core_reparent(core: hw->core, new_parent: !new_parent ? NULL : new_parent->core); |
2735 | } |
2736 | |
2737 | /** |
2738 | * clk_has_parent - check if a clock is a possible parent for another |
2739 | * @clk: clock source |
2740 | * @parent: parent clock source |
2741 | * |
2742 | * This function can be used in drivers that need to check that a clock can be |
2743 | * the parent of another without actually changing the parent. |
2744 | * |
2745 | * Returns true if @parent is a possible parent for @clk, false otherwise. |
2746 | */ |
2747 | bool clk_has_parent(const struct clk *clk, const struct clk *parent) |
2748 | { |
2749 | /* NULL clocks should be nops, so return success if either is NULL. */ |
2750 | if (!clk || !parent) |
2751 | return true; |
2752 | |
2753 | return clk_core_has_parent(core: clk->core, parent: parent->core); |
2754 | } |
2755 | EXPORT_SYMBOL_GPL(clk_has_parent); |
2756 | |
2757 | static int clk_core_set_parent_nolock(struct clk_core *core, |
2758 | struct clk_core *parent) |
2759 | { |
2760 | int ret = 0; |
2761 | int p_index = 0; |
2762 | unsigned long p_rate = 0; |
2763 | |
2764 | lockdep_assert_held(&prepare_lock); |
2765 | |
2766 | if (!core) |
2767 | return 0; |
2768 | |
2769 | if (core->parent == parent) |
2770 | return 0; |
2771 | |
2772 | /* verify ops for multi-parent clks */ |
2773 | if (core->num_parents > 1 && !core->ops->set_parent) |
2774 | return -EPERM; |
2775 | |
2776 | /* check that we are allowed to re-parent if the clock is in use */ |
2777 | if ((core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) |
2778 | return -EBUSY; |
2779 | |
2780 | if (clk_core_rate_is_protected(core)) |
2781 | return -EBUSY; |
2782 | |
2783 | /* try finding the new parent index */ |
2784 | if (parent) { |
2785 | p_index = clk_fetch_parent_index(core, parent); |
2786 | if (p_index < 0) { |
2787 | pr_debug("%s: clk %s can not be parent of clk %s\n" , |
2788 | __func__, parent->name, core->name); |
2789 | return p_index; |
2790 | } |
2791 | p_rate = parent->rate; |
2792 | } |
2793 | |
2794 | ret = clk_pm_runtime_get(core); |
2795 | if (ret) |
2796 | return ret; |
2797 | |
2798 | /* propagate PRE_RATE_CHANGE notifications */ |
2799 | ret = __clk_speculate_rates(core, parent_rate: p_rate); |
2800 | |
2801 | /* abort if a driver objects */ |
2802 | if (ret & NOTIFY_STOP_MASK) |
2803 | goto runtime_put; |
2804 | |
2805 | /* do the re-parent */ |
2806 | ret = __clk_set_parent(core, parent, p_index); |
2807 | |
2808 | /* propagate rate an accuracy recalculation accordingly */ |
2809 | if (ret) { |
2810 | __clk_recalc_rates(core, update_req: true, ABORT_RATE_CHANGE); |
2811 | } else { |
2812 | __clk_recalc_rates(core, update_req: true, POST_RATE_CHANGE); |
2813 | __clk_recalc_accuracies(core); |
2814 | } |
2815 | |
2816 | runtime_put: |
2817 | clk_pm_runtime_put(core); |
2818 | |
2819 | return ret; |
2820 | } |
2821 | |
2822 | int clk_hw_set_parent(struct clk_hw *hw, struct clk_hw *parent) |
2823 | { |
2824 | return clk_core_set_parent_nolock(core: hw->core, parent: parent->core); |
2825 | } |
2826 | EXPORT_SYMBOL_GPL(clk_hw_set_parent); |
2827 | |
2828 | /** |
2829 | * clk_set_parent - switch the parent of a mux clk |
2830 | * @clk: the mux clk whose input we are switching |
2831 | * @parent: the new input to clk |
2832 | * |
2833 | * Re-parent clk to use parent as its new input source. If clk is in |
2834 | * prepared state, the clk will get enabled for the duration of this call. If |
2835 | * that's not acceptable for a specific clk (Eg: the consumer can't handle |
2836 | * that, the reparenting is glitchy in hardware, etc), use the |
2837 | * CLK_SET_PARENT_GATE flag to allow reparenting only when clk is unprepared. |
2838 | * |
2839 | * After successfully changing clk's parent clk_set_parent will update the |
2840 | * clk topology, sysfs topology and propagate rate recalculation via |
2841 | * __clk_recalc_rates. |
2842 | * |
2843 | * Returns 0 on success, -EERROR otherwise. |
2844 | */ |
2845 | int clk_set_parent(struct clk *clk, struct clk *parent) |
2846 | { |
2847 | int ret; |
2848 | |
2849 | if (!clk) |
2850 | return 0; |
2851 | |
2852 | clk_prepare_lock(); |
2853 | |
2854 | if (clk->exclusive_count) |
2855 | clk_core_rate_unprotect(core: clk->core); |
2856 | |
2857 | ret = clk_core_set_parent_nolock(core: clk->core, |
2858 | parent: parent ? parent->core : NULL); |
2859 | |
2860 | if (clk->exclusive_count) |
2861 | clk_core_rate_protect(core: clk->core); |
2862 | |
2863 | clk_prepare_unlock(); |
2864 | |
2865 | return ret; |
2866 | } |
2867 | EXPORT_SYMBOL_GPL(clk_set_parent); |
2868 | |
2869 | static int clk_core_set_phase_nolock(struct clk_core *core, int degrees) |
2870 | { |
2871 | int ret = -EINVAL; |
2872 | |
2873 | lockdep_assert_held(&prepare_lock); |
2874 | |
2875 | if (!core) |
2876 | return 0; |
2877 | |
2878 | if (clk_core_rate_is_protected(core)) |
2879 | return -EBUSY; |
2880 | |
2881 | trace_clk_set_phase(core, phase: degrees); |
2882 | |
2883 | if (core->ops->set_phase) { |
2884 | ret = core->ops->set_phase(core->hw, degrees); |
2885 | if (!ret) |
2886 | core->phase = degrees; |
2887 | } |
2888 | |
2889 | trace_clk_set_phase_complete(core, phase: degrees); |
2890 | |
2891 | return ret; |
2892 | } |
2893 | |
2894 | /** |
2895 | * clk_set_phase - adjust the phase shift of a clock signal |
2896 | * @clk: clock signal source |
2897 | * @degrees: number of degrees the signal is shifted |
2898 | * |
2899 | * Shifts the phase of a clock signal by the specified |
2900 | * degrees. Returns 0 on success, -EERROR otherwise. |
2901 | * |
2902 | * This function makes no distinction about the input or reference |
2903 | * signal that we adjust the clock signal phase against. For example |
2904 | * phase locked-loop clock signal generators we may shift phase with |
2905 | * respect to feedback clock signal input, but for other cases the |
2906 | * clock phase may be shifted with respect to some other, unspecified |
2907 | * signal. |
2908 | * |
2909 | * Additionally the concept of phase shift does not propagate through |
2910 | * the clock tree hierarchy, which sets it apart from clock rates and |
2911 | * clock accuracy. A parent clock phase attribute does not have an |
2912 | * impact on the phase attribute of a child clock. |
2913 | */ |
2914 | int clk_set_phase(struct clk *clk, int degrees) |
2915 | { |
2916 | int ret; |
2917 | |
2918 | if (!clk) |
2919 | return 0; |
2920 | |
2921 | /* sanity check degrees */ |
2922 | degrees %= 360; |
2923 | if (degrees < 0) |
2924 | degrees += 360; |
2925 | |
2926 | clk_prepare_lock(); |
2927 | |
2928 | if (clk->exclusive_count) |
2929 | clk_core_rate_unprotect(core: clk->core); |
2930 | |
2931 | ret = clk_core_set_phase_nolock(core: clk->core, degrees); |
2932 | |
2933 | if (clk->exclusive_count) |
2934 | clk_core_rate_protect(core: clk->core); |
2935 | |
2936 | clk_prepare_unlock(); |
2937 | |
2938 | return ret; |
2939 | } |
2940 | EXPORT_SYMBOL_GPL(clk_set_phase); |
2941 | |
2942 | static int clk_core_get_phase(struct clk_core *core) |
2943 | { |
2944 | int ret; |
2945 | |
2946 | lockdep_assert_held(&prepare_lock); |
2947 | if (!core->ops->get_phase) |
2948 | return 0; |
2949 | |
2950 | /* Always try to update cached phase if possible */ |
2951 | ret = core->ops->get_phase(core->hw); |
2952 | if (ret >= 0) |
2953 | core->phase = ret; |
2954 | |
2955 | return ret; |
2956 | } |
2957 | |
2958 | /** |
2959 | * clk_get_phase - return the phase shift of a clock signal |
2960 | * @clk: clock signal source |
2961 | * |
2962 | * Returns the phase shift of a clock node in degrees, otherwise returns |
2963 | * -EERROR. |
2964 | */ |
2965 | int clk_get_phase(struct clk *clk) |
2966 | { |
2967 | int ret; |
2968 | |
2969 | if (!clk) |
2970 | return 0; |
2971 | |
2972 | clk_prepare_lock(); |
2973 | ret = clk_core_get_phase(core: clk->core); |
2974 | clk_prepare_unlock(); |
2975 | |
2976 | return ret; |
2977 | } |
2978 | EXPORT_SYMBOL_GPL(clk_get_phase); |
2979 | |
2980 | static void clk_core_reset_duty_cycle_nolock(struct clk_core *core) |
2981 | { |
2982 | /* Assume a default value of 50% */ |
2983 | core->duty.num = 1; |
2984 | core->duty.den = 2; |
2985 | } |
2986 | |
2987 | static int clk_core_update_duty_cycle_parent_nolock(struct clk_core *core); |
2988 | |
2989 | static int clk_core_update_duty_cycle_nolock(struct clk_core *core) |
2990 | { |
2991 | struct clk_duty *duty = &core->duty; |
2992 | int ret = 0; |
2993 | |
2994 | if (!core->ops->get_duty_cycle) |
2995 | return clk_core_update_duty_cycle_parent_nolock(core); |
2996 | |
2997 | ret = core->ops->get_duty_cycle(core->hw, duty); |
2998 | if (ret) |
2999 | goto reset; |
3000 | |
3001 | /* Don't trust the clock provider too much */ |
3002 | if (duty->den == 0 || duty->num > duty->den) { |
3003 | ret = -EINVAL; |
3004 | goto reset; |
3005 | } |
3006 | |
3007 | return 0; |
3008 | |
3009 | reset: |
3010 | clk_core_reset_duty_cycle_nolock(core); |
3011 | return ret; |
3012 | } |
3013 | |
3014 | static int clk_core_update_duty_cycle_parent_nolock(struct clk_core *core) |
3015 | { |
3016 | int ret = 0; |
3017 | |
3018 | if (core->parent && |
3019 | core->flags & CLK_DUTY_CYCLE_PARENT) { |
3020 | ret = clk_core_update_duty_cycle_nolock(core: core->parent); |
3021 | memcpy(&core->duty, &core->parent->duty, sizeof(core->duty)); |
3022 | } else { |
3023 | clk_core_reset_duty_cycle_nolock(core); |
3024 | } |
3025 | |
3026 | return ret; |
3027 | } |
3028 | |
3029 | static int clk_core_set_duty_cycle_parent_nolock(struct clk_core *core, |
3030 | struct clk_duty *duty); |
3031 | |
3032 | static int clk_core_set_duty_cycle_nolock(struct clk_core *core, |
3033 | struct clk_duty *duty) |
3034 | { |
3035 | int ret; |
3036 | |
3037 | lockdep_assert_held(&prepare_lock); |
3038 | |
3039 | if (clk_core_rate_is_protected(core)) |
3040 | return -EBUSY; |
3041 | |
3042 | trace_clk_set_duty_cycle(core, duty); |
3043 | |
3044 | if (!core->ops->set_duty_cycle) |
3045 | return clk_core_set_duty_cycle_parent_nolock(core, duty); |
3046 | |
3047 | ret = core->ops->set_duty_cycle(core->hw, duty); |
3048 | if (!ret) |
3049 | memcpy(&core->duty, duty, sizeof(*duty)); |
3050 | |
3051 | trace_clk_set_duty_cycle_complete(core, duty); |
3052 | |
3053 | return ret; |
3054 | } |
3055 | |
3056 | static int clk_core_set_duty_cycle_parent_nolock(struct clk_core *core, |
3057 | struct clk_duty *duty) |
3058 | { |
3059 | int ret = 0; |
3060 | |
3061 | if (core->parent && |
3062 | core->flags & (CLK_DUTY_CYCLE_PARENT | CLK_SET_RATE_PARENT)) { |
3063 | ret = clk_core_set_duty_cycle_nolock(core: core->parent, duty); |
3064 | memcpy(&core->duty, &core->parent->duty, sizeof(core->duty)); |
3065 | } |
3066 | |
3067 | return ret; |
3068 | } |
3069 | |
3070 | /** |
3071 | * clk_set_duty_cycle - adjust the duty cycle ratio of a clock signal |
3072 | * @clk: clock signal source |
3073 | * @num: numerator of the duty cycle ratio to be applied |
3074 | * @den: denominator of the duty cycle ratio to be applied |
3075 | * |
3076 | * Apply the duty cycle ratio if the ratio is valid and the clock can |
3077 | * perform this operation |
3078 | * |
3079 | * Returns (0) on success, a negative errno otherwise. |
3080 | */ |
3081 | int clk_set_duty_cycle(struct clk *clk, unsigned int num, unsigned int den) |
3082 | { |
3083 | int ret; |
3084 | struct clk_duty duty; |
3085 | |
3086 | if (!clk) |
3087 | return 0; |
3088 | |
3089 | /* sanity check the ratio */ |
3090 | if (den == 0 || num > den) |
3091 | return -EINVAL; |
3092 | |
3093 | duty.num = num; |
3094 | duty.den = den; |
3095 | |
3096 | clk_prepare_lock(); |
3097 | |
3098 | if (clk->exclusive_count) |
3099 | clk_core_rate_unprotect(core: clk->core); |
3100 | |
3101 | ret = clk_core_set_duty_cycle_nolock(core: clk->core, duty: &duty); |
3102 | |
3103 | if (clk->exclusive_count) |
3104 | clk_core_rate_protect(core: clk->core); |
3105 | |
3106 | clk_prepare_unlock(); |
3107 | |
3108 | return ret; |
3109 | } |
3110 | EXPORT_SYMBOL_GPL(clk_set_duty_cycle); |
3111 | |
3112 | static int clk_core_get_scaled_duty_cycle(struct clk_core *core, |
3113 | unsigned int scale) |
3114 | { |
3115 | struct clk_duty *duty = &core->duty; |
3116 | int ret; |
3117 | |
3118 | clk_prepare_lock(); |
3119 | |
3120 | ret = clk_core_update_duty_cycle_nolock(core); |
3121 | if (!ret) |
3122 | ret = mult_frac(scale, duty->num, duty->den); |
3123 | |
3124 | clk_prepare_unlock(); |
3125 | |
3126 | return ret; |
3127 | } |
3128 | |
3129 | /** |
3130 | * clk_get_scaled_duty_cycle - return the duty cycle ratio of a clock signal |
3131 | * @clk: clock signal source |
3132 | * @scale: scaling factor to be applied to represent the ratio as an integer |
3133 | * |
3134 | * Returns the duty cycle ratio of a clock node multiplied by the provided |
3135 | * scaling factor, or negative errno on error. |
3136 | */ |
3137 | int clk_get_scaled_duty_cycle(struct clk *clk, unsigned int scale) |
3138 | { |
3139 | if (!clk) |
3140 | return 0; |
3141 | |
3142 | return clk_core_get_scaled_duty_cycle(core: clk->core, scale); |
3143 | } |
3144 | EXPORT_SYMBOL_GPL(clk_get_scaled_duty_cycle); |
3145 | |
3146 | /** |
3147 | * clk_is_match - check if two clk's point to the same hardware clock |
3148 | * @p: clk compared against q |
3149 | * @q: clk compared against p |
3150 | * |
3151 | * Returns true if the two struct clk pointers both point to the same hardware |
3152 | * clock node. Put differently, returns true if struct clk *p and struct clk *q |
3153 | * share the same struct clk_core object. |
3154 | * |
3155 | * Returns false otherwise. Note that two NULL clks are treated as matching. |
3156 | */ |
3157 | bool clk_is_match(const struct clk *p, const struct clk *q) |
3158 | { |
3159 | /* trivial case: identical struct clk's or both NULL */ |
3160 | if (p == q) |
3161 | return true; |
3162 | |
3163 | /* true if clk->core pointers match. Avoid dereferencing garbage */ |
3164 | if (!IS_ERR_OR_NULL(ptr: p) && !IS_ERR_OR_NULL(ptr: q)) |
3165 | if (p->core == q->core) |
3166 | return true; |
3167 | |
3168 | return false; |
3169 | } |
3170 | EXPORT_SYMBOL_GPL(clk_is_match); |
3171 | |
3172 | /*** debugfs support ***/ |
3173 | |
3174 | #ifdef CONFIG_DEBUG_FS |
3175 | #include <linux/debugfs.h> |
3176 | |
3177 | static struct dentry *rootdir; |
3178 | static int inited = 0; |
3179 | static DEFINE_MUTEX(clk_debug_lock); |
3180 | static HLIST_HEAD(clk_debug_list); |
3181 | |
3182 | static struct hlist_head *orphan_list[] = { |
3183 | &clk_orphan_list, |
3184 | NULL, |
3185 | }; |
3186 | |
3187 | static void clk_summary_show_one(struct seq_file *s, struct clk_core *c, |
3188 | int level) |
3189 | { |
3190 | int phase; |
3191 | struct clk *clk_user; |
3192 | int multi_node = 0; |
3193 | |
3194 | seq_printf(m: s, fmt: "%*s%-*s %-7d %-8d %-8d %-11lu %-10lu " , |
3195 | level * 3 + 1, "" , |
3196 | 35 - level * 3, c->name, |
3197 | c->enable_count, c->prepare_count, c->protect_count, |
3198 | clk_core_get_rate_recalc(core: c), |
3199 | clk_core_get_accuracy_recalc(core: c)); |
3200 | |
3201 | phase = clk_core_get_phase(core: c); |
3202 | if (phase >= 0) |
3203 | seq_printf(m: s, fmt: "%-5d" , phase); |
3204 | else |
3205 | seq_puts(m: s, s: "-----" ); |
3206 | |
3207 | seq_printf(m: s, fmt: " %-6d" , clk_core_get_scaled_duty_cycle(core: c, scale: 100000)); |
3208 | |
3209 | if (c->ops->is_enabled) |
3210 | seq_printf(m: s, fmt: " %5c " , clk_core_is_enabled(core: c) ? 'Y' : 'N'); |
3211 | else if (!c->ops->enable) |
3212 | seq_printf(m: s, fmt: " %5c " , 'Y'); |
3213 | else |
3214 | seq_printf(m: s, fmt: " %5c " , '?'); |
3215 | |
3216 | hlist_for_each_entry(clk_user, &c->clks, clks_node) { |
3217 | seq_printf(m: s, fmt: "%*s%-*s %-25s\n" , |
3218 | level * 3 + 2 + 105 * multi_node, "" , |
3219 | 30, |
3220 | clk_user->dev_id ? clk_user->dev_id : "deviceless" , |
3221 | clk_user->con_id ? clk_user->con_id : "no_connection_id" ); |
3222 | |
3223 | multi_node = 1; |
3224 | } |
3225 | |
3226 | } |
3227 | |
3228 | static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c, |
3229 | int level) |
3230 | { |
3231 | struct clk_core *child; |
3232 | |
3233 | clk_pm_runtime_get(core: c); |
3234 | clk_summary_show_one(s, c, level); |
3235 | clk_pm_runtime_put(core: c); |
3236 | |
3237 | hlist_for_each_entry(child, &c->children, child_node) |
3238 | clk_summary_show_subtree(s, c: child, level: level + 1); |
3239 | } |
3240 | |
3241 | static int clk_summary_show(struct seq_file *s, void *data) |
3242 | { |
3243 | struct clk_core *c; |
3244 | struct hlist_head **lists = s->private; |
3245 | |
3246 | seq_puts(m: s, s: " enable prepare protect duty hardware connection\n" ); |
3247 | seq_puts(m: s, s: " clock count count count rate accuracy phase cycle enable consumer id\n" ); |
3248 | seq_puts(m: s, s: "---------------------------------------------------------------------------------------------------------------------------------------------\n" ); |
3249 | |
3250 | |
3251 | clk_prepare_lock(); |
3252 | |
3253 | for (; *lists; lists++) |
3254 | hlist_for_each_entry(c, *lists, child_node) |
3255 | clk_summary_show_subtree(s, c, level: 0); |
3256 | |
3257 | clk_prepare_unlock(); |
3258 | |
3259 | return 0; |
3260 | } |
3261 | DEFINE_SHOW_ATTRIBUTE(clk_summary); |
3262 | |
3263 | static void clk_dump_one(struct seq_file *s, struct clk_core *c, int level) |
3264 | { |
3265 | int phase; |
3266 | unsigned long min_rate, max_rate; |
3267 | |
3268 | clk_core_get_boundaries(core: c, min_rate: &min_rate, max_rate: &max_rate); |
3269 | |
3270 | /* This should be JSON format, i.e. elements separated with a comma */ |
3271 | seq_printf(m: s, fmt: "\"%s\": { " , c->name); |
3272 | seq_printf(m: s, fmt: "\"enable_count\": %d," , c->enable_count); |
3273 | seq_printf(m: s, fmt: "\"prepare_count\": %d," , c->prepare_count); |
3274 | seq_printf(m: s, fmt: "\"protect_count\": %d," , c->protect_count); |
3275 | seq_printf(m: s, fmt: "\"rate\": %lu," , clk_core_get_rate_recalc(core: c)); |
3276 | seq_printf(m: s, fmt: "\"min_rate\": %lu," , min_rate); |
3277 | seq_printf(m: s, fmt: "\"max_rate\": %lu," , max_rate); |
3278 | seq_printf(m: s, fmt: "\"accuracy\": %lu," , clk_core_get_accuracy_recalc(core: c)); |
3279 | phase = clk_core_get_phase(core: c); |
3280 | if (phase >= 0) |
3281 | seq_printf(m: s, fmt: "\"phase\": %d," , phase); |
3282 | seq_printf(m: s, fmt: "\"duty_cycle\": %u" , |
3283 | clk_core_get_scaled_duty_cycle(core: c, scale: 100000)); |
3284 | } |
3285 | |
3286 | static void clk_dump_subtree(struct seq_file *s, struct clk_core *c, int level) |
3287 | { |
3288 | struct clk_core *child; |
3289 | |
3290 | clk_dump_one(s, c, level); |
3291 | |
3292 | hlist_for_each_entry(child, &c->children, child_node) { |
3293 | seq_putc(m: s, c: ','); |
3294 | clk_dump_subtree(s, c: child, level: level + 1); |
3295 | } |
3296 | |
3297 | seq_putc(m: s, c: '}'); |
3298 | } |
3299 | |
3300 | static int clk_dump_show(struct seq_file *s, void *data) |
3301 | { |
3302 | struct clk_core *c; |
3303 | bool first_node = true; |
3304 | struct hlist_head **lists = s->private; |
3305 | |
3306 | seq_putc(m: s, c: '{'); |
3307 | clk_prepare_lock(); |
3308 | |
3309 | for (; *lists; lists++) { |
3310 | hlist_for_each_entry(c, *lists, child_node) { |
3311 | if (!first_node) |
3312 | seq_putc(m: s, c: ','); |
3313 | first_node = false; |
3314 | clk_dump_subtree(s, c, level: 0); |
3315 | } |
3316 | } |
3317 | |
3318 | clk_prepare_unlock(); |
3319 | |
3320 | seq_puts(m: s, s: "}\n" ); |
3321 | return 0; |
3322 | } |
3323 | DEFINE_SHOW_ATTRIBUTE(clk_dump); |
3324 | |
3325 | #undef CLOCK_ALLOW_WRITE_DEBUGFS |
3326 | #ifdef CLOCK_ALLOW_WRITE_DEBUGFS |
3327 | /* |
3328 | * This can be dangerous, therefore don't provide any real compile time |
3329 | * configuration option for this feature. |
3330 | * People who want to use this will need to modify the source code directly. |
3331 | */ |
3332 | static int clk_rate_set(void *data, u64 val) |
3333 | { |
3334 | struct clk_core *core = data; |
3335 | int ret; |
3336 | |
3337 | clk_prepare_lock(); |
3338 | ret = clk_core_set_rate_nolock(core, val); |
3339 | clk_prepare_unlock(); |
3340 | |
3341 | return ret; |
3342 | } |
3343 | |
3344 | #define clk_rate_mode 0644 |
3345 | |
3346 | static int clk_phase_set(void *data, u64 val) |
3347 | { |
3348 | struct clk_core *core = data; |
3349 | int degrees = do_div(val, 360); |
3350 | int ret; |
3351 | |
3352 | clk_prepare_lock(); |
3353 | ret = clk_core_set_phase_nolock(core, degrees); |
3354 | clk_prepare_unlock(); |
3355 | |
3356 | return ret; |
3357 | } |
3358 | |
3359 | #define clk_phase_mode 0644 |
3360 | |
3361 | static int clk_prepare_enable_set(void *data, u64 val) |
3362 | { |
3363 | struct clk_core *core = data; |
3364 | int ret = 0; |
3365 | |
3366 | if (val) |
3367 | ret = clk_prepare_enable(core->hw->clk); |
3368 | else |
3369 | clk_disable_unprepare(core->hw->clk); |
3370 | |
3371 | return ret; |
3372 | } |
3373 | |
3374 | static int clk_prepare_enable_get(void *data, u64 *val) |
3375 | { |
3376 | struct clk_core *core = data; |
3377 | |
3378 | *val = core->enable_count && core->prepare_count; |
3379 | return 0; |
3380 | } |
3381 | |
3382 | DEFINE_DEBUGFS_ATTRIBUTE(clk_prepare_enable_fops, clk_prepare_enable_get, |
3383 | clk_prepare_enable_set, "%llu\n" ); |
3384 | |
3385 | #else |
3386 | #define clk_rate_set NULL |
3387 | #define clk_rate_mode 0444 |
3388 | |
3389 | #define clk_phase_set NULL |
3390 | #define clk_phase_mode 0644 |
3391 | #endif |
3392 | |
3393 | static int clk_rate_get(void *data, u64 *val) |
3394 | { |
3395 | struct clk_core *core = data; |
3396 | |
3397 | clk_prepare_lock(); |
3398 | *val = clk_core_get_rate_recalc(core); |
3399 | clk_prepare_unlock(); |
3400 | |
3401 | return 0; |
3402 | } |
3403 | |
3404 | DEFINE_DEBUGFS_ATTRIBUTE(clk_rate_fops, clk_rate_get, clk_rate_set, "%llu\n" ); |
3405 | |
3406 | static int clk_phase_get(void *data, u64 *val) |
3407 | { |
3408 | struct clk_core *core = data; |
3409 | |
3410 | *val = core->phase; |
3411 | return 0; |
3412 | } |
3413 | |
3414 | DEFINE_DEBUGFS_ATTRIBUTE(clk_phase_fops, clk_phase_get, clk_phase_set, "%llu\n" ); |
3415 | |
3416 | static const struct { |
3417 | unsigned long flag; |
3418 | const char *name; |
3419 | } clk_flags[] = { |
3420 | #define ENTRY(f) { f, #f } |
3421 | ENTRY(CLK_SET_RATE_GATE), |
3422 | ENTRY(CLK_SET_PARENT_GATE), |
3423 | ENTRY(CLK_SET_RATE_PARENT), |
3424 | ENTRY(CLK_IGNORE_UNUSED), |
3425 | ENTRY(CLK_GET_RATE_NOCACHE), |
3426 | ENTRY(CLK_SET_RATE_NO_REPARENT), |
3427 | ENTRY(CLK_GET_ACCURACY_NOCACHE), |
3428 | ENTRY(CLK_RECALC_NEW_RATES), |
3429 | ENTRY(CLK_SET_RATE_UNGATE), |
3430 | ENTRY(CLK_IS_CRITICAL), |
3431 | ENTRY(CLK_OPS_PARENT_ENABLE), |
3432 | ENTRY(CLK_DUTY_CYCLE_PARENT), |
3433 | #undef ENTRY |
3434 | }; |
3435 | |
3436 | static int clk_flags_show(struct seq_file *s, void *data) |
3437 | { |
3438 | struct clk_core *core = s->private; |
3439 | unsigned long flags = core->flags; |
3440 | unsigned int i; |
3441 | |
3442 | for (i = 0; flags && i < ARRAY_SIZE(clk_flags); i++) { |
3443 | if (flags & clk_flags[i].flag) { |
3444 | seq_printf(m: s, fmt: "%s\n" , clk_flags[i].name); |
3445 | flags &= ~clk_flags[i].flag; |
3446 | } |
3447 | } |
3448 | if (flags) { |
3449 | /* Unknown flags */ |
3450 | seq_printf(m: s, fmt: "0x%lx\n" , flags); |
3451 | } |
3452 | |
3453 | return 0; |
3454 | } |
3455 | DEFINE_SHOW_ATTRIBUTE(clk_flags); |
3456 | |
3457 | static void possible_parent_show(struct seq_file *s, struct clk_core *core, |
3458 | unsigned int i, char terminator) |
3459 | { |
3460 | struct clk_core *parent; |
3461 | const char *name = NULL; |
3462 | |
3463 | /* |
3464 | * Go through the following options to fetch a parent's name. |
3465 | * |
3466 | * 1. Fetch the registered parent clock and use its name |
3467 | * 2. Use the global (fallback) name if specified |
3468 | * 3. Use the local fw_name if provided |
3469 | * 4. Fetch parent clock's clock-output-name if DT index was set |
3470 | * |
3471 | * This may still fail in some cases, such as when the parent is |
3472 | * specified directly via a struct clk_hw pointer, but it isn't |
3473 | * registered (yet). |
3474 | */ |
3475 | parent = clk_core_get_parent_by_index(core, index: i); |
3476 | if (parent) { |
3477 | seq_puts(m: s, s: parent->name); |
3478 | } else if (core->parents[i].name) { |
3479 | seq_puts(m: s, s: core->parents[i].name); |
3480 | } else if (core->parents[i].fw_name) { |
3481 | seq_printf(m: s, fmt: "<%s>(fw)" , core->parents[i].fw_name); |
3482 | } else { |
3483 | if (core->parents[i].index >= 0) |
3484 | name = of_clk_get_parent_name(np: core->of_node, index: core->parents[i].index); |
3485 | if (!name) |
3486 | name = "(missing)" ; |
3487 | |
3488 | seq_puts(m: s, s: name); |
3489 | } |
3490 | |
3491 | seq_putc(m: s, c: terminator); |
3492 | } |
3493 | |
3494 | static int possible_parents_show(struct seq_file *s, void *data) |
3495 | { |
3496 | struct clk_core *core = s->private; |
3497 | int i; |
3498 | |
3499 | for (i = 0; i < core->num_parents - 1; i++) |
3500 | possible_parent_show(s, core, i, terminator: ' '); |
3501 | |
3502 | possible_parent_show(s, core, i, terminator: '\n'); |
3503 | |
3504 | return 0; |
3505 | } |
3506 | DEFINE_SHOW_ATTRIBUTE(possible_parents); |
3507 | |
3508 | static int current_parent_show(struct seq_file *s, void *data) |
3509 | { |
3510 | struct clk_core *core = s->private; |
3511 | |
3512 | if (core->parent) |
3513 | seq_printf(m: s, fmt: "%s\n" , core->parent->name); |
3514 | |
3515 | return 0; |
3516 | } |
3517 | DEFINE_SHOW_ATTRIBUTE(current_parent); |
3518 | |
3519 | #ifdef CLOCK_ALLOW_WRITE_DEBUGFS |
3520 | static ssize_t current_parent_write(struct file *file, const char __user *ubuf, |
3521 | size_t count, loff_t *ppos) |
3522 | { |
3523 | struct seq_file *s = file->private_data; |
3524 | struct clk_core *core = s->private; |
3525 | struct clk_core *parent; |
3526 | u8 idx; |
3527 | int err; |
3528 | |
3529 | err = kstrtou8_from_user(ubuf, count, 0, &idx); |
3530 | if (err < 0) |
3531 | return err; |
3532 | |
3533 | parent = clk_core_get_parent_by_index(core, idx); |
3534 | if (!parent) |
3535 | return -ENOENT; |
3536 | |
3537 | clk_prepare_lock(); |
3538 | err = clk_core_set_parent_nolock(core, parent); |
3539 | clk_prepare_unlock(); |
3540 | if (err) |
3541 | return err; |
3542 | |
3543 | return count; |
3544 | } |
3545 | |
3546 | static const struct file_operations current_parent_rw_fops = { |
3547 | .open = current_parent_open, |
3548 | .write = current_parent_write, |
3549 | .read = seq_read, |
3550 | .llseek = seq_lseek, |
3551 | .release = single_release, |
3552 | }; |
3553 | #endif |
3554 | |
3555 | static int clk_duty_cycle_show(struct seq_file *s, void *data) |
3556 | { |
3557 | struct clk_core *core = s->private; |
3558 | struct clk_duty *duty = &core->duty; |
3559 | |
3560 | seq_printf(m: s, fmt: "%u/%u\n" , duty->num, duty->den); |
3561 | |
3562 | return 0; |
3563 | } |
3564 | DEFINE_SHOW_ATTRIBUTE(clk_duty_cycle); |
3565 | |
3566 | static int clk_min_rate_show(struct seq_file *s, void *data) |
3567 | { |
3568 | struct clk_core *core = s->private; |
3569 | unsigned long min_rate, max_rate; |
3570 | |
3571 | clk_prepare_lock(); |
3572 | clk_core_get_boundaries(core, min_rate: &min_rate, max_rate: &max_rate); |
3573 | clk_prepare_unlock(); |
3574 | seq_printf(m: s, fmt: "%lu\n" , min_rate); |
3575 | |
3576 | return 0; |
3577 | } |
3578 | DEFINE_SHOW_ATTRIBUTE(clk_min_rate); |
3579 | |
3580 | static int clk_max_rate_show(struct seq_file *s, void *data) |
3581 | { |
3582 | struct clk_core *core = s->private; |
3583 | unsigned long min_rate, max_rate; |
3584 | |
3585 | clk_prepare_lock(); |
3586 | clk_core_get_boundaries(core, min_rate: &min_rate, max_rate: &max_rate); |
3587 | clk_prepare_unlock(); |
3588 | seq_printf(m: s, fmt: "%lu\n" , max_rate); |
3589 | |
3590 | return 0; |
3591 | } |
3592 | DEFINE_SHOW_ATTRIBUTE(clk_max_rate); |
3593 | |
3594 | static void clk_debug_create_one(struct clk_core *core, struct dentry *pdentry) |
3595 | { |
3596 | struct dentry *root; |
3597 | |
3598 | if (!core || !pdentry) |
3599 | return; |
3600 | |
3601 | root = debugfs_create_dir(name: core->name, parent: pdentry); |
3602 | core->dentry = root; |
3603 | |
3604 | debugfs_create_file(name: "clk_rate" , clk_rate_mode, parent: root, data: core, |
3605 | fops: &clk_rate_fops); |
3606 | debugfs_create_file(name: "clk_min_rate" , mode: 0444, parent: root, data: core, fops: &clk_min_rate_fops); |
3607 | debugfs_create_file(name: "clk_max_rate" , mode: 0444, parent: root, data: core, fops: &clk_max_rate_fops); |
3608 | debugfs_create_ulong(name: "clk_accuracy" , mode: 0444, parent: root, value: &core->accuracy); |
3609 | debugfs_create_file(name: "clk_phase" , clk_phase_mode, parent: root, data: core, |
3610 | fops: &clk_phase_fops); |
3611 | debugfs_create_file(name: "clk_flags" , mode: 0444, parent: root, data: core, fops: &clk_flags_fops); |
3612 | debugfs_create_u32(name: "clk_prepare_count" , mode: 0444, parent: root, value: &core->prepare_count); |
3613 | debugfs_create_u32(name: "clk_enable_count" , mode: 0444, parent: root, value: &core->enable_count); |
3614 | debugfs_create_u32(name: "clk_protect_count" , mode: 0444, parent: root, value: &core->protect_count); |
3615 | debugfs_create_u32(name: "clk_notifier_count" , mode: 0444, parent: root, value: &core->notifier_count); |
3616 | debugfs_create_file(name: "clk_duty_cycle" , mode: 0444, parent: root, data: core, |
3617 | fops: &clk_duty_cycle_fops); |
3618 | #ifdef CLOCK_ALLOW_WRITE_DEBUGFS |
3619 | debugfs_create_file("clk_prepare_enable" , 0644, root, core, |
3620 | &clk_prepare_enable_fops); |
3621 | |
3622 | if (core->num_parents > 1) |
3623 | debugfs_create_file("clk_parent" , 0644, root, core, |
3624 | ¤t_parent_rw_fops); |
3625 | else |
3626 | #endif |
3627 | if (core->num_parents > 0) |
3628 | debugfs_create_file(name: "clk_parent" , mode: 0444, parent: root, data: core, |
3629 | fops: ¤t_parent_fops); |
3630 | |
3631 | if (core->num_parents > 1) |
3632 | debugfs_create_file(name: "clk_possible_parents" , mode: 0444, parent: root, data: core, |
3633 | fops: &possible_parents_fops); |
3634 | |
3635 | if (core->ops->debug_init) |
3636 | core->ops->debug_init(core->hw, core->dentry); |
3637 | } |
3638 | |
3639 | /** |
3640 | * clk_debug_register - add a clk node to the debugfs clk directory |
3641 | * @core: the clk being added to the debugfs clk directory |
3642 | * |
3643 | * Dynamically adds a clk to the debugfs clk directory if debugfs has been |
3644 | * initialized. Otherwise it bails out early since the debugfs clk directory |
3645 | * will be created lazily by clk_debug_init as part of a late_initcall. |
3646 | */ |
3647 | static void clk_debug_register(struct clk_core *core) |
3648 | { |
3649 | mutex_lock(&clk_debug_lock); |
3650 | hlist_add_head(n: &core->debug_node, h: &clk_debug_list); |
3651 | if (inited) |
3652 | clk_debug_create_one(core, pdentry: rootdir); |
3653 | mutex_unlock(lock: &clk_debug_lock); |
3654 | } |
3655 | |
3656 | /** |
3657 | * clk_debug_unregister - remove a clk node from the debugfs clk directory |
3658 | * @core: the clk being removed from the debugfs clk directory |
3659 | * |
3660 | * Dynamically removes a clk and all its child nodes from the |
3661 | * debugfs clk directory if clk->dentry points to debugfs created by |
3662 | * clk_debug_register in __clk_core_init. |
3663 | */ |
3664 | static void clk_debug_unregister(struct clk_core *core) |
3665 | { |
3666 | mutex_lock(&clk_debug_lock); |
3667 | hlist_del_init(n: &core->debug_node); |
3668 | debugfs_remove_recursive(dentry: core->dentry); |
3669 | core->dentry = NULL; |
3670 | mutex_unlock(lock: &clk_debug_lock); |
3671 | } |
3672 | |
3673 | /** |
3674 | * clk_debug_init - lazily populate the debugfs clk directory |
3675 | * |
3676 | * clks are often initialized very early during boot before memory can be |
3677 | * dynamically allocated and well before debugfs is setup. This function |
3678 | * populates the debugfs clk directory once at boot-time when we know that |
3679 | * debugfs is setup. It should only be called once at boot-time, all other clks |
3680 | * added dynamically will be done so with clk_debug_register. |
3681 | */ |
3682 | static int __init clk_debug_init(void) |
3683 | { |
3684 | struct clk_core *core; |
3685 | |
3686 | #ifdef CLOCK_ALLOW_WRITE_DEBUGFS |
3687 | pr_warn("\n" ); |
3688 | pr_warn("********************************************************************\n" ); |
3689 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n" ); |
3690 | pr_warn("** **\n" ); |
3691 | pr_warn("** WRITEABLE clk DebugFS SUPPORT HAS BEEN ENABLED IN THIS KERNEL **\n" ); |
3692 | pr_warn("** **\n" ); |
3693 | pr_warn("** This means that this kernel is built to expose clk operations **\n" ); |
3694 | pr_warn("** such as parent or rate setting, enabling, disabling, etc. **\n" ); |
3695 | pr_warn("** to userspace, which may compromise security on your system. **\n" ); |
3696 | pr_warn("** **\n" ); |
3697 | pr_warn("** If you see this message and you are not debugging the **\n" ); |
3698 | pr_warn("** kernel, report this immediately to your vendor! **\n" ); |
3699 | pr_warn("** **\n" ); |
3700 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n" ); |
3701 | pr_warn("********************************************************************\n" ); |
3702 | #endif |
3703 | |
3704 | rootdir = debugfs_create_dir(name: "clk" , NULL); |
3705 | |
3706 | debugfs_create_file(name: "clk_summary" , mode: 0444, parent: rootdir, data: &all_lists, |
3707 | fops: &clk_summary_fops); |
3708 | debugfs_create_file(name: "clk_dump" , mode: 0444, parent: rootdir, data: &all_lists, |
3709 | fops: &clk_dump_fops); |
3710 | debugfs_create_file(name: "clk_orphan_summary" , mode: 0444, parent: rootdir, data: &orphan_list, |
3711 | fops: &clk_summary_fops); |
3712 | debugfs_create_file(name: "clk_orphan_dump" , mode: 0444, parent: rootdir, data: &orphan_list, |
3713 | fops: &clk_dump_fops); |
3714 | |
3715 | mutex_lock(&clk_debug_lock); |
3716 | hlist_for_each_entry(core, &clk_debug_list, debug_node) |
3717 | clk_debug_create_one(core, pdentry: rootdir); |
3718 | |
3719 | inited = 1; |
3720 | mutex_unlock(lock: &clk_debug_lock); |
3721 | |
3722 | return 0; |
3723 | } |
3724 | late_initcall(clk_debug_init); |
3725 | #else |
3726 | static inline void clk_debug_register(struct clk_core *core) { } |
3727 | static inline void clk_debug_unregister(struct clk_core *core) |
3728 | { |
3729 | } |
3730 | #endif |
3731 | |
3732 | static void clk_core_reparent_orphans_nolock(void) |
3733 | { |
3734 | struct clk_core *orphan; |
3735 | struct hlist_node *tmp2; |
3736 | |
3737 | /* |
3738 | * walk the list of orphan clocks and reparent any that newly finds a |
3739 | * parent. |
3740 | */ |
3741 | hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { |
3742 | struct clk_core *parent = __clk_init_parent(core: orphan); |
3743 | |
3744 | /* |
3745 | * We need to use __clk_set_parent_before() and _after() to |
3746 | * properly migrate any prepare/enable count of the orphan |
3747 | * clock. This is important for CLK_IS_CRITICAL clocks, which |
3748 | * are enabled during init but might not have a parent yet. |
3749 | */ |
3750 | if (parent) { |
3751 | /* update the clk tree topology */ |
3752 | __clk_set_parent_before(core: orphan, parent); |
3753 | __clk_set_parent_after(core: orphan, parent, NULL); |
3754 | __clk_recalc_accuracies(core: orphan); |
3755 | __clk_recalc_rates(core: orphan, update_req: true, msg: 0); |
3756 | |
3757 | /* |
3758 | * __clk_init_parent() will set the initial req_rate to |
3759 | * 0 if the clock doesn't have clk_ops::recalc_rate and |
3760 | * is an orphan when it's registered. |
3761 | * |
3762 | * 'req_rate' is used by clk_set_rate_range() and |
3763 | * clk_put() to trigger a clk_set_rate() call whenever |
3764 | * the boundaries are modified. Let's make sure |
3765 | * 'req_rate' is set to something non-zero so that |
3766 | * clk_set_rate_range() doesn't drop the frequency. |
3767 | */ |
3768 | orphan->req_rate = orphan->rate; |
3769 | } |
3770 | } |
3771 | } |
3772 | |
3773 | /** |
3774 | * __clk_core_init - initialize the data structures in a struct clk_core |
3775 | * @core: clk_core being initialized |
3776 | * |
3777 | * Initializes the lists in struct clk_core, queries the hardware for the |
3778 | * parent and rate and sets them both. |
3779 | */ |
3780 | static int __clk_core_init(struct clk_core *core) |
3781 | { |
3782 | int ret; |
3783 | struct clk_core *parent; |
3784 | unsigned long rate; |
3785 | int phase; |
3786 | |
3787 | clk_prepare_lock(); |
3788 | |
3789 | /* |
3790 | * Set hw->core after grabbing the prepare_lock to synchronize with |
3791 | * callers of clk_core_fill_parent_index() where we treat hw->core |
3792 | * being NULL as the clk not being registered yet. This is crucial so |
3793 | * that clks aren't parented until their parent is fully registered. |
3794 | */ |
3795 | core->hw->core = core; |
3796 | |
3797 | ret = clk_pm_runtime_get(core); |
3798 | if (ret) |
3799 | goto unlock; |
3800 | |
3801 | /* check to see if a clock with this name is already registered */ |
3802 | if (clk_core_lookup(name: core->name)) { |
3803 | pr_debug("%s: clk %s already initialized\n" , |
3804 | __func__, core->name); |
3805 | ret = -EEXIST; |
3806 | goto out; |
3807 | } |
3808 | |
3809 | /* check that clk_ops are sane. See Documentation/driver-api/clk.rst */ |
3810 | if (core->ops->set_rate && |
3811 | !((core->ops->round_rate || core->ops->determine_rate) && |
3812 | core->ops->recalc_rate)) { |
3813 | pr_err("%s: %s must implement .round_rate or .determine_rate in addition to .recalc_rate\n" , |
3814 | __func__, core->name); |
3815 | ret = -EINVAL; |
3816 | goto out; |
3817 | } |
3818 | |
3819 | if (core->ops->set_parent && !core->ops->get_parent) { |
3820 | pr_err("%s: %s must implement .get_parent & .set_parent\n" , |
3821 | __func__, core->name); |
3822 | ret = -EINVAL; |
3823 | goto out; |
3824 | } |
3825 | |
3826 | if (core->ops->set_parent && !core->ops->determine_rate) { |
3827 | pr_err("%s: %s must implement .set_parent & .determine_rate\n" , |
3828 | __func__, core->name); |
3829 | ret = -EINVAL; |
3830 | goto out; |
3831 | } |
3832 | |
3833 | if (core->num_parents > 1 && !core->ops->get_parent) { |
3834 | pr_err("%s: %s must implement .get_parent as it has multi parents\n" , |
3835 | __func__, core->name); |
3836 | ret = -EINVAL; |
3837 | goto out; |
3838 | } |
3839 | |
3840 | if (core->ops->set_rate_and_parent && |
3841 | !(core->ops->set_parent && core->ops->set_rate)) { |
3842 | pr_err("%s: %s must implement .set_parent & .set_rate\n" , |
3843 | __func__, core->name); |
3844 | ret = -EINVAL; |
3845 | goto out; |
3846 | } |
3847 | |
3848 | /* |
3849 | * optional platform-specific magic |
3850 | * |
3851 | * The .init callback is not used by any of the basic clock types, but |
3852 | * exists for weird hardware that must perform initialization magic for |
3853 | * CCF to get an accurate view of clock for any other callbacks. It may |
3854 | * also be used needs to perform dynamic allocations. Such allocation |
3855 | * must be freed in the terminate() callback. |
3856 | * This callback shall not be used to initialize the parameters state, |
3857 | * such as rate, parent, etc ... |
3858 | * |
3859 | * If it exist, this callback should called before any other callback of |
3860 | * the clock |
3861 | */ |
3862 | if (core->ops->init) { |
3863 | ret = core->ops->init(core->hw); |
3864 | if (ret) |
3865 | goto out; |
3866 | } |
3867 | |
3868 | parent = core->parent = __clk_init_parent(core); |
3869 | |
3870 | /* |
3871 | * Populate core->parent if parent has already been clk_core_init'd. If |
3872 | * parent has not yet been clk_core_init'd then place clk in the orphan |
3873 | * list. If clk doesn't have any parents then place it in the root |
3874 | * clk list. |
3875 | * |
3876 | * Every time a new clk is clk_init'd then we walk the list of orphan |
3877 | * clocks and re-parent any that are children of the clock currently |
3878 | * being clk_init'd. |
3879 | */ |
3880 | if (parent) { |
3881 | hlist_add_head(n: &core->child_node, h: &parent->children); |
3882 | core->orphan = parent->orphan; |
3883 | } else if (!core->num_parents) { |
3884 | hlist_add_head(n: &core->child_node, h: &clk_root_list); |
3885 | core->orphan = false; |
3886 | } else { |
3887 | hlist_add_head(n: &core->child_node, h: &clk_orphan_list); |
3888 | core->orphan = true; |
3889 | } |
3890 | |
3891 | /* |
3892 | * Set clk's accuracy. The preferred method is to use |
3893 | * .recalc_accuracy. For simple clocks and lazy developers the default |
3894 | * fallback is to use the parent's accuracy. If a clock doesn't have a |
3895 | * parent (or is orphaned) then accuracy is set to zero (perfect |
3896 | * clock). |
3897 | */ |
3898 | if (core->ops->recalc_accuracy) |
3899 | core->accuracy = core->ops->recalc_accuracy(core->hw, |
3900 | clk_core_get_accuracy_no_lock(core: parent)); |
3901 | else if (parent) |
3902 | core->accuracy = parent->accuracy; |
3903 | else |
3904 | core->accuracy = 0; |
3905 | |
3906 | /* |
3907 | * Set clk's phase by clk_core_get_phase() caching the phase. |
3908 | * Since a phase is by definition relative to its parent, just |
3909 | * query the current clock phase, or just assume it's in phase. |
3910 | */ |
3911 | phase = clk_core_get_phase(core); |
3912 | if (phase < 0) { |
3913 | ret = phase; |
3914 | pr_warn("%s: Failed to get phase for clk '%s'\n" , __func__, |
3915 | core->name); |
3916 | goto out; |
3917 | } |
3918 | |
3919 | /* |
3920 | * Set clk's duty cycle. |
3921 | */ |
3922 | clk_core_update_duty_cycle_nolock(core); |
3923 | |
3924 | /* |
3925 | * Set clk's rate. The preferred method is to use .recalc_rate. For |
3926 | * simple clocks and lazy developers the default fallback is to use the |
3927 | * parent's rate. If a clock doesn't have a parent (or is orphaned) |
3928 | * then rate is set to zero. |
3929 | */ |
3930 | if (core->ops->recalc_rate) |
3931 | rate = core->ops->recalc_rate(core->hw, |
3932 | clk_core_get_rate_nolock(core: parent)); |
3933 | else if (parent) |
3934 | rate = parent->rate; |
3935 | else |
3936 | rate = 0; |
3937 | core->rate = core->req_rate = rate; |
3938 | |
3939 | /* |
3940 | * Enable CLK_IS_CRITICAL clocks so newly added critical clocks |
3941 | * don't get accidentally disabled when walking the orphan tree and |
3942 | * reparenting clocks |
3943 | */ |
3944 | if (core->flags & CLK_IS_CRITICAL) { |
3945 | ret = clk_core_prepare(core); |
3946 | if (ret) { |
3947 | pr_warn("%s: critical clk '%s' failed to prepare\n" , |
3948 | __func__, core->name); |
3949 | goto out; |
3950 | } |
3951 | |
3952 | ret = clk_core_enable_lock(core); |
3953 | if (ret) { |
3954 | pr_warn("%s: critical clk '%s' failed to enable\n" , |
3955 | __func__, core->name); |
3956 | clk_core_unprepare(core); |
3957 | goto out; |
3958 | } |
3959 | } |
3960 | |
3961 | clk_core_reparent_orphans_nolock(); |
3962 | |
3963 | kref_init(kref: &core->ref); |
3964 | out: |
3965 | clk_pm_runtime_put(core); |
3966 | unlock: |
3967 | if (ret) { |
3968 | hlist_del_init(n: &core->child_node); |
3969 | core->hw->core = NULL; |
3970 | } |
3971 | |
3972 | clk_prepare_unlock(); |
3973 | |
3974 | if (!ret) |
3975 | clk_debug_register(core); |
3976 | |
3977 | return ret; |
3978 | } |
3979 | |
3980 | /** |
3981 | * clk_core_link_consumer - Add a clk consumer to the list of consumers in a clk_core |
3982 | * @core: clk to add consumer to |
3983 | * @clk: consumer to link to a clk |
3984 | */ |
3985 | static void clk_core_link_consumer(struct clk_core *core, struct clk *clk) |
3986 | { |
3987 | clk_prepare_lock(); |
3988 | hlist_add_head(n: &clk->clks_node, h: &core->clks); |
3989 | clk_prepare_unlock(); |
3990 | } |
3991 | |
3992 | /** |
3993 | * clk_core_unlink_consumer - Remove a clk consumer from the list of consumers in a clk_core |
3994 | * @clk: consumer to unlink |
3995 | */ |
3996 | static void clk_core_unlink_consumer(struct clk *clk) |
3997 | { |
3998 | lockdep_assert_held(&prepare_lock); |
3999 | hlist_del(n: &clk->clks_node); |
4000 | } |
4001 | |
4002 | /** |
4003 | * alloc_clk - Allocate a clk consumer, but leave it unlinked to the clk_core |
4004 | * @core: clk to allocate a consumer for |
4005 | * @dev_id: string describing device name |
4006 | * @con_id: connection ID string on device |
4007 | * |
4008 | * Returns: clk consumer left unlinked from the consumer list |
4009 | */ |
4010 | static struct clk *alloc_clk(struct clk_core *core, const char *dev_id, |
4011 | const char *con_id) |
4012 | { |
4013 | struct clk *clk; |
4014 | |
4015 | clk = kzalloc(size: sizeof(*clk), GFP_KERNEL); |
4016 | if (!clk) |
4017 | return ERR_PTR(error: -ENOMEM); |
4018 | |
4019 | clk->core = core; |
4020 | clk->dev_id = dev_id; |
4021 | clk->con_id = kstrdup_const(s: con_id, GFP_KERNEL); |
4022 | clk->max_rate = ULONG_MAX; |
4023 | |
4024 | return clk; |
4025 | } |
4026 | |
4027 | /** |
4028 | * free_clk - Free a clk consumer |
4029 | * @clk: clk consumer to free |
4030 | * |
4031 | * Note, this assumes the clk has been unlinked from the clk_core consumer |
4032 | * list. |
4033 | */ |
4034 | static void free_clk(struct clk *clk) |
4035 | { |
4036 | kfree_const(x: clk->con_id); |
4037 | kfree(objp: clk); |
4038 | } |
4039 | |
4040 | /** |
4041 | * clk_hw_create_clk: Allocate and link a clk consumer to a clk_core given |
4042 | * a clk_hw |
4043 | * @dev: clk consumer device |
4044 | * @hw: clk_hw associated with the clk being consumed |
4045 | * @dev_id: string describing device name |
4046 | * @con_id: connection ID string on device |
4047 | * |
4048 | * This is the main function used to create a clk pointer for use by clk |
4049 | * consumers. It connects a consumer to the clk_core and clk_hw structures |
4050 | * used by the framework and clk provider respectively. |
4051 | */ |
4052 | struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw, |
4053 | const char *dev_id, const char *con_id) |
4054 | { |
4055 | struct clk *clk; |
4056 | struct clk_core *core; |
4057 | |
4058 | /* This is to allow this function to be chained to others */ |
4059 | if (IS_ERR_OR_NULL(ptr: hw)) |
4060 | return ERR_CAST(ptr: hw); |
4061 | |
4062 | core = hw->core; |
4063 | clk = alloc_clk(core, dev_id, con_id); |
4064 | if (IS_ERR(ptr: clk)) |
4065 | return clk; |
4066 | clk->dev = dev; |
4067 | |
4068 | if (!try_module_get(module: core->owner)) { |
4069 | free_clk(clk); |
4070 | return ERR_PTR(error: -ENOENT); |
4071 | } |
4072 | |
4073 | kref_get(kref: &core->ref); |
4074 | clk_core_link_consumer(core, clk); |
4075 | |
4076 | return clk; |
4077 | } |
4078 | |
4079 | /** |
4080 | * clk_hw_get_clk - get clk consumer given an clk_hw |
4081 | * @hw: clk_hw associated with the clk being consumed |
4082 | * @con_id: connection ID string on device |
4083 | * |
4084 | * Returns: new clk consumer |
4085 | * This is the function to be used by providers which need |
4086 | * to get a consumer clk and act on the clock element |
4087 | * Calls to this function must be balanced with calls clk_put() |
4088 | */ |
4089 | struct clk *clk_hw_get_clk(struct clk_hw *hw, const char *con_id) |
4090 | { |
4091 | struct device *dev = hw->core->dev; |
4092 | const char *name = dev ? dev_name(dev) : NULL; |
4093 | |
4094 | return clk_hw_create_clk(dev, hw, dev_id: name, con_id); |
4095 | } |
4096 | EXPORT_SYMBOL(clk_hw_get_clk); |
4097 | |
4098 | static int clk_cpy_name(const char **dst_p, const char *src, bool must_exist) |
4099 | { |
4100 | const char *dst; |
4101 | |
4102 | if (!src) { |
4103 | if (must_exist) |
4104 | return -EINVAL; |
4105 | return 0; |
4106 | } |
4107 | |
4108 | *dst_p = dst = kstrdup_const(s: src, GFP_KERNEL); |
4109 | if (!dst) |
4110 | return -ENOMEM; |
4111 | |
4112 | return 0; |
4113 | } |
4114 | |
4115 | static int clk_core_populate_parent_map(struct clk_core *core, |
4116 | const struct clk_init_data *init) |
4117 | { |
4118 | u8 num_parents = init->num_parents; |
4119 | const char * const *parent_names = init->parent_names; |
4120 | const struct clk_hw **parent_hws = init->parent_hws; |
4121 | const struct clk_parent_data *parent_data = init->parent_data; |
4122 | int i, ret = 0; |
4123 | struct clk_parent_map *parents, *parent; |
4124 | |
4125 | if (!num_parents) |
4126 | return 0; |
4127 | |
4128 | /* |
4129 | * Avoid unnecessary string look-ups of clk_core's possible parents by |
4130 | * having a cache of names/clk_hw pointers to clk_core pointers. |
4131 | */ |
4132 | parents = kcalloc(n: num_parents, size: sizeof(*parents), GFP_KERNEL); |
4133 | core->parents = parents; |
4134 | if (!parents) |
4135 | return -ENOMEM; |
4136 | |
4137 | /* Copy everything over because it might be __initdata */ |
4138 | for (i = 0, parent = parents; i < num_parents; i++, parent++) { |
4139 | parent->index = -1; |
4140 | if (parent_names) { |
4141 | /* throw a WARN if any entries are NULL */ |
4142 | WARN(!parent_names[i], |
4143 | "%s: invalid NULL in %s's .parent_names\n" , |
4144 | __func__, core->name); |
4145 | ret = clk_cpy_name(dst_p: &parent->name, src: parent_names[i], |
4146 | must_exist: true); |
4147 | } else if (parent_data) { |
4148 | parent->hw = parent_data[i].hw; |
4149 | parent->index = parent_data[i].index; |
4150 | ret = clk_cpy_name(dst_p: &parent->fw_name, |
4151 | src: parent_data[i].fw_name, must_exist: false); |
4152 | if (!ret) |
4153 | ret = clk_cpy_name(dst_p: &parent->name, |
4154 | src: parent_data[i].name, |
4155 | must_exist: false); |
4156 | } else if (parent_hws) { |
4157 | parent->hw = parent_hws[i]; |
4158 | } else { |
4159 | ret = -EINVAL; |
4160 | WARN(1, "Must specify parents if num_parents > 0\n" ); |
4161 | } |
4162 | |
4163 | if (ret) { |
4164 | do { |
4165 | kfree_const(x: parents[i].name); |
4166 | kfree_const(x: parents[i].fw_name); |
4167 | } while (--i >= 0); |
4168 | kfree(objp: parents); |
4169 | |
4170 | return ret; |
4171 | } |
4172 | } |
4173 | |
4174 | return 0; |
4175 | } |
4176 | |
4177 | static void clk_core_free_parent_map(struct clk_core *core) |
4178 | { |
4179 | int i = core->num_parents; |
4180 | |
4181 | if (!core->num_parents) |
4182 | return; |
4183 | |
4184 | while (--i >= 0) { |
4185 | kfree_const(x: core->parents[i].name); |
4186 | kfree_const(x: core->parents[i].fw_name); |
4187 | } |
4188 | |
4189 | kfree(objp: core->parents); |
4190 | } |
4191 | |
4192 | static struct clk * |
4193 | __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw) |
4194 | { |
4195 | int ret; |
4196 | struct clk_core *core; |
4197 | const struct clk_init_data *init = hw->init; |
4198 | |
4199 | /* |
4200 | * The init data is not supposed to be used outside of registration path. |
4201 | * Set it to NULL so that provider drivers can't use it either and so that |
4202 | * we catch use of hw->init early on in the core. |
4203 | */ |
4204 | hw->init = NULL; |
4205 | |
4206 | core = kzalloc(size: sizeof(*core), GFP_KERNEL); |
4207 | if (!core) { |
4208 | ret = -ENOMEM; |
4209 | goto fail_out; |
4210 | } |
4211 | |
4212 | core->name = kstrdup_const(s: init->name, GFP_KERNEL); |
4213 | if (!core->name) { |
4214 | ret = -ENOMEM; |
4215 | goto fail_name; |
4216 | } |
4217 | |
4218 | if (WARN_ON(!init->ops)) { |
4219 | ret = -EINVAL; |
4220 | goto fail_ops; |
4221 | } |
4222 | core->ops = init->ops; |
4223 | |
4224 | if (dev && pm_runtime_enabled(dev)) |
4225 | core->rpm_enabled = true; |
4226 | core->dev = dev; |
4227 | core->of_node = np; |
4228 | if (dev && dev->driver) |
4229 | core->owner = dev->driver->owner; |
4230 | core->hw = hw; |
4231 | core->flags = init->flags; |
4232 | core->num_parents = init->num_parents; |
4233 | core->min_rate = 0; |
4234 | core->max_rate = ULONG_MAX; |
4235 | |
4236 | ret = clk_core_populate_parent_map(core, init); |
4237 | if (ret) |
4238 | goto fail_parents; |
4239 | |
4240 | INIT_HLIST_HEAD(&core->clks); |
4241 | |
4242 | /* |
4243 | * Don't call clk_hw_create_clk() here because that would pin the |
4244 | * provider module to itself and prevent it from ever being removed. |
4245 | */ |
4246 | hw->clk = alloc_clk(core, NULL, NULL); |
4247 | if (IS_ERR(ptr: hw->clk)) { |
4248 | ret = PTR_ERR(ptr: hw->clk); |
4249 | goto fail_create_clk; |
4250 | } |
4251 | |
4252 | clk_core_link_consumer(core, clk: hw->clk); |
4253 | |
4254 | ret = __clk_core_init(core); |
4255 | if (!ret) |
4256 | return hw->clk; |
4257 | |
4258 | clk_prepare_lock(); |
4259 | clk_core_unlink_consumer(clk: hw->clk); |
4260 | clk_prepare_unlock(); |
4261 | |
4262 | free_clk(clk: hw->clk); |
4263 | hw->clk = NULL; |
4264 | |
4265 | fail_create_clk: |
4266 | clk_core_free_parent_map(core); |
4267 | fail_parents: |
4268 | fail_ops: |
4269 | kfree_const(x: core->name); |
4270 | fail_name: |
4271 | kfree(objp: core); |
4272 | fail_out: |
4273 | return ERR_PTR(error: ret); |
4274 | } |
4275 | |
4276 | /** |
4277 | * dev_or_parent_of_node() - Get device node of @dev or @dev's parent |
4278 | * @dev: Device to get device node of |
4279 | * |
4280 | * Return: device node pointer of @dev, or the device node pointer of |
4281 | * @dev->parent if dev doesn't have a device node, or NULL if neither |
4282 | * @dev or @dev->parent have a device node. |
4283 | */ |
4284 | static struct device_node *dev_or_parent_of_node(struct device *dev) |
4285 | { |
4286 | struct device_node *np; |
4287 | |
4288 | if (!dev) |
4289 | return NULL; |
4290 | |
4291 | np = dev_of_node(dev); |
4292 | if (!np) |
4293 | np = dev_of_node(dev: dev->parent); |
4294 | |
4295 | return np; |
4296 | } |
4297 | |
4298 | /** |
4299 | * clk_register - allocate a new clock, register it and return an opaque cookie |
4300 | * @dev: device that is registering this clock |
4301 | * @hw: link to hardware-specific clock data |
4302 | * |
4303 | * clk_register is the *deprecated* interface for populating the clock tree with |
4304 | * new clock nodes. Use clk_hw_register() instead. |
4305 | * |
4306 | * Returns: a pointer to the newly allocated struct clk which |
4307 | * cannot be dereferenced by driver code but may be used in conjunction with the |
4308 | * rest of the clock API. In the event of an error clk_register will return an |
4309 | * error code; drivers must test for an error code after calling clk_register. |
4310 | */ |
4311 | struct clk *clk_register(struct device *dev, struct clk_hw *hw) |
4312 | { |
4313 | return __clk_register(dev, np: dev_or_parent_of_node(dev), hw); |
4314 | } |
4315 | EXPORT_SYMBOL_GPL(clk_register); |
4316 | |
4317 | /** |
4318 | * clk_hw_register - register a clk_hw and return an error code |
4319 | * @dev: device that is registering this clock |
4320 | * @hw: link to hardware-specific clock data |
4321 | * |
4322 | * clk_hw_register is the primary interface for populating the clock tree with |
4323 | * new clock nodes. It returns an integer equal to zero indicating success or |
4324 | * less than zero indicating failure. Drivers must test for an error code after |
4325 | * calling clk_hw_register(). |
4326 | */ |
4327 | int clk_hw_register(struct device *dev, struct clk_hw *hw) |
4328 | { |
4329 | return PTR_ERR_OR_ZERO(ptr: __clk_register(dev, np: dev_or_parent_of_node(dev), |
4330 | hw)); |
4331 | } |
4332 | EXPORT_SYMBOL_GPL(clk_hw_register); |
4333 | |
4334 | /* |
4335 | * of_clk_hw_register - register a clk_hw and return an error code |
4336 | * @node: device_node of device that is registering this clock |
4337 | * @hw: link to hardware-specific clock data |
4338 | * |
4339 | * of_clk_hw_register() is the primary interface for populating the clock tree |
4340 | * with new clock nodes when a struct device is not available, but a struct |
4341 | * device_node is. It returns an integer equal to zero indicating success or |
4342 | * less than zero indicating failure. Drivers must test for an error code after |
4343 | * calling of_clk_hw_register(). |
4344 | */ |
4345 | int of_clk_hw_register(struct device_node *node, struct clk_hw *hw) |
4346 | { |
4347 | return PTR_ERR_OR_ZERO(ptr: __clk_register(NULL, np: node, hw)); |
4348 | } |
4349 | EXPORT_SYMBOL_GPL(of_clk_hw_register); |
4350 | |
4351 | /* Free memory allocated for a clock. */ |
4352 | static void __clk_release(struct kref *ref) |
4353 | { |
4354 | struct clk_core *core = container_of(ref, struct clk_core, ref); |
4355 | |
4356 | lockdep_assert_held(&prepare_lock); |
4357 | |
4358 | clk_core_free_parent_map(core); |
4359 | kfree_const(x: core->name); |
4360 | kfree(objp: core); |
4361 | } |
4362 | |
4363 | /* |
4364 | * Empty clk_ops for unregistered clocks. These are used temporarily |
4365 | * after clk_unregister() was called on a clock and until last clock |
4366 | * consumer calls clk_put() and the struct clk object is freed. |
4367 | */ |
4368 | static int clk_nodrv_prepare_enable(struct clk_hw *hw) |
4369 | { |
4370 | return -ENXIO; |
4371 | } |
4372 | |
4373 | static void clk_nodrv_disable_unprepare(struct clk_hw *hw) |
4374 | { |
4375 | WARN_ON_ONCE(1); |
4376 | } |
4377 | |
4378 | static int clk_nodrv_set_rate(struct clk_hw *hw, unsigned long rate, |
4379 | unsigned long parent_rate) |
4380 | { |
4381 | return -ENXIO; |
4382 | } |
4383 | |
4384 | static int clk_nodrv_set_parent(struct clk_hw *hw, u8 index) |
4385 | { |
4386 | return -ENXIO; |
4387 | } |
4388 | |
4389 | static int clk_nodrv_determine_rate(struct clk_hw *hw, |
4390 | struct clk_rate_request *req) |
4391 | { |
4392 | return -ENXIO; |
4393 | } |
4394 | |
4395 | static const struct clk_ops clk_nodrv_ops = { |
4396 | .enable = clk_nodrv_prepare_enable, |
4397 | .disable = clk_nodrv_disable_unprepare, |
4398 | .prepare = clk_nodrv_prepare_enable, |
4399 | .unprepare = clk_nodrv_disable_unprepare, |
4400 | .determine_rate = clk_nodrv_determine_rate, |
4401 | .set_rate = clk_nodrv_set_rate, |
4402 | .set_parent = clk_nodrv_set_parent, |
4403 | }; |
4404 | |
4405 | static void clk_core_evict_parent_cache_subtree(struct clk_core *root, |
4406 | const struct clk_core *target) |
4407 | { |
4408 | int i; |
4409 | struct clk_core *child; |
4410 | |
4411 | for (i = 0; i < root->num_parents; i++) |
4412 | if (root->parents[i].core == target) |
4413 | root->parents[i].core = NULL; |
4414 | |
4415 | hlist_for_each_entry(child, &root->children, child_node) |
4416 | clk_core_evict_parent_cache_subtree(root: child, target); |
4417 | } |
4418 | |
4419 | /* Remove this clk from all parent caches */ |
4420 | static void clk_core_evict_parent_cache(struct clk_core *core) |
4421 | { |
4422 | const struct hlist_head **lists; |
4423 | struct clk_core *root; |
4424 | |
4425 | lockdep_assert_held(&prepare_lock); |
4426 | |
4427 | for (lists = all_lists; *lists; lists++) |
4428 | hlist_for_each_entry(root, *lists, child_node) |
4429 | clk_core_evict_parent_cache_subtree(root, target: core); |
4430 | |
4431 | } |
4432 | |
4433 | /** |
4434 | * clk_unregister - unregister a currently registered clock |
4435 | * @clk: clock to unregister |
4436 | */ |
4437 | void clk_unregister(struct clk *clk) |
4438 | { |
4439 | unsigned long flags; |
4440 | const struct clk_ops *ops; |
4441 | |
4442 | if (!clk || WARN_ON_ONCE(IS_ERR(clk))) |
4443 | return; |
4444 | |
4445 | clk_debug_unregister(core: clk->core); |
4446 | |
4447 | clk_prepare_lock(); |
4448 | |
4449 | ops = clk->core->ops; |
4450 | if (ops == &clk_nodrv_ops) { |
4451 | pr_err("%s: unregistered clock: %s\n" , __func__, |
4452 | clk->core->name); |
4453 | goto unlock; |
4454 | } |
4455 | /* |
4456 | * Assign empty clock ops for consumers that might still hold |
4457 | * a reference to this clock. |
4458 | */ |
4459 | flags = clk_enable_lock(); |
4460 | clk->core->ops = &clk_nodrv_ops; |
4461 | clk_enable_unlock(flags); |
4462 | |
4463 | if (ops->terminate) |
4464 | ops->terminate(clk->core->hw); |
4465 | |
4466 | if (!hlist_empty(h: &clk->core->children)) { |
4467 | struct clk_core *child; |
4468 | struct hlist_node *t; |
4469 | |
4470 | /* Reparent all children to the orphan list. */ |
4471 | hlist_for_each_entry_safe(child, t, &clk->core->children, |
4472 | child_node) |
4473 | clk_core_set_parent_nolock(core: child, NULL); |
4474 | } |
4475 | |
4476 | clk_core_evict_parent_cache(core: clk->core); |
4477 | |
4478 | hlist_del_init(n: &clk->core->child_node); |
4479 | |
4480 | if (clk->core->prepare_count) |
4481 | pr_warn("%s: unregistering prepared clock: %s\n" , |
4482 | __func__, clk->core->name); |
4483 | |
4484 | if (clk->core->protect_count) |
4485 | pr_warn("%s: unregistering protected clock: %s\n" , |
4486 | __func__, clk->core->name); |
4487 | |
4488 | kref_put(kref: &clk->core->ref, release: __clk_release); |
4489 | free_clk(clk); |
4490 | unlock: |
4491 | clk_prepare_unlock(); |
4492 | } |
4493 | EXPORT_SYMBOL_GPL(clk_unregister); |
4494 | |
4495 | /** |
4496 | * clk_hw_unregister - unregister a currently registered clk_hw |
4497 | * @hw: hardware-specific clock data to unregister |
4498 | */ |
4499 | void clk_hw_unregister(struct clk_hw *hw) |
4500 | { |
4501 | clk_unregister(hw->clk); |
4502 | } |
4503 | EXPORT_SYMBOL_GPL(clk_hw_unregister); |
4504 | |
4505 | static void devm_clk_unregister_cb(struct device *dev, void *res) |
4506 | { |
4507 | clk_unregister(*(struct clk **)res); |
4508 | } |
4509 | |
4510 | static void devm_clk_hw_unregister_cb(struct device *dev, void *res) |
4511 | { |
4512 | clk_hw_unregister(*(struct clk_hw **)res); |
4513 | } |
4514 | |
4515 | /** |
4516 | * devm_clk_register - resource managed clk_register() |
4517 | * @dev: device that is registering this clock |
4518 | * @hw: link to hardware-specific clock data |
4519 | * |
4520 | * Managed clk_register(). This function is *deprecated*, use devm_clk_hw_register() instead. |
4521 | * |
4522 | * Clocks returned from this function are automatically clk_unregister()ed on |
4523 | * driver detach. See clk_register() for more information. |
4524 | */ |
4525 | struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw) |
4526 | { |
4527 | struct clk *clk; |
4528 | struct clk **clkp; |
4529 | |
4530 | clkp = devres_alloc(devm_clk_unregister_cb, sizeof(*clkp), GFP_KERNEL); |
4531 | if (!clkp) |
4532 | return ERR_PTR(error: -ENOMEM); |
4533 | |
4534 | clk = clk_register(dev, hw); |
4535 | if (!IS_ERR(ptr: clk)) { |
4536 | *clkp = clk; |
4537 | devres_add(dev, res: clkp); |
4538 | } else { |
4539 | devres_free(res: clkp); |
4540 | } |
4541 | |
4542 | return clk; |
4543 | } |
4544 | EXPORT_SYMBOL_GPL(devm_clk_register); |
4545 | |
4546 | /** |
4547 | * devm_clk_hw_register - resource managed clk_hw_register() |
4548 | * @dev: device that is registering this clock |
4549 | * @hw: link to hardware-specific clock data |
4550 | * |
4551 | * Managed clk_hw_register(). Clocks registered by this function are |
4552 | * automatically clk_hw_unregister()ed on driver detach. See clk_hw_register() |
4553 | * for more information. |
4554 | */ |
4555 | int devm_clk_hw_register(struct device *dev, struct clk_hw *hw) |
4556 | { |
4557 | struct clk_hw **hwp; |
4558 | int ret; |
4559 | |
4560 | hwp = devres_alloc(devm_clk_hw_unregister_cb, sizeof(*hwp), GFP_KERNEL); |
4561 | if (!hwp) |
4562 | return -ENOMEM; |
4563 | |
4564 | ret = clk_hw_register(dev, hw); |
4565 | if (!ret) { |
4566 | *hwp = hw; |
4567 | devres_add(dev, res: hwp); |
4568 | } else { |
4569 | devres_free(res: hwp); |
4570 | } |
4571 | |
4572 | return ret; |
4573 | } |
4574 | EXPORT_SYMBOL_GPL(devm_clk_hw_register); |
4575 | |
4576 | static void devm_clk_release(struct device *dev, void *res) |
4577 | { |
4578 | clk_put(clk: *(struct clk **)res); |
4579 | } |
4580 | |
4581 | /** |
4582 | * devm_clk_hw_get_clk - resource managed clk_hw_get_clk() |
4583 | * @dev: device that is registering this clock |
4584 | * @hw: clk_hw associated with the clk being consumed |
4585 | * @con_id: connection ID string on device |
4586 | * |
4587 | * Managed clk_hw_get_clk(). Clocks got with this function are |
4588 | * automatically clk_put() on driver detach. See clk_put() |
4589 | * for more information. |
4590 | */ |
4591 | struct clk *devm_clk_hw_get_clk(struct device *dev, struct clk_hw *hw, |
4592 | const char *con_id) |
4593 | { |
4594 | struct clk *clk; |
4595 | struct clk **clkp; |
4596 | |
4597 | /* This should not happen because it would mean we have drivers |
4598 | * passing around clk_hw pointers instead of having the caller use |
4599 | * proper clk_get() style APIs |
4600 | */ |
4601 | WARN_ON_ONCE(dev != hw->core->dev); |
4602 | |
4603 | clkp = devres_alloc(devm_clk_release, sizeof(*clkp), GFP_KERNEL); |
4604 | if (!clkp) |
4605 | return ERR_PTR(error: -ENOMEM); |
4606 | |
4607 | clk = clk_hw_get_clk(hw, con_id); |
4608 | if (!IS_ERR(ptr: clk)) { |
4609 | *clkp = clk; |
4610 | devres_add(dev, res: clkp); |
4611 | } else { |
4612 | devres_free(res: clkp); |
4613 | } |
4614 | |
4615 | return clk; |
4616 | } |
4617 | EXPORT_SYMBOL_GPL(devm_clk_hw_get_clk); |
4618 | |
4619 | /* |
4620 | * clkdev helpers |
4621 | */ |
4622 | |
4623 | void __clk_put(struct clk *clk) |
4624 | { |
4625 | struct module *owner; |
4626 | |
4627 | if (!clk || WARN_ON_ONCE(IS_ERR(clk))) |
4628 | return; |
4629 | |
4630 | clk_prepare_lock(); |
4631 | |
4632 | /* |
4633 | * Before calling clk_put, all calls to clk_rate_exclusive_get() from a |
4634 | * given user should be balanced with calls to clk_rate_exclusive_put() |
4635 | * and by that same consumer |
4636 | */ |
4637 | if (WARN_ON(clk->exclusive_count)) { |
4638 | /* We voiced our concern, let's sanitize the situation */ |
4639 | clk->core->protect_count -= (clk->exclusive_count - 1); |
4640 | clk_core_rate_unprotect(core: clk->core); |
4641 | clk->exclusive_count = 0; |
4642 | } |
4643 | |
4644 | hlist_del(n: &clk->clks_node); |
4645 | |
4646 | /* If we had any boundaries on that clock, let's drop them. */ |
4647 | if (clk->min_rate > 0 || clk->max_rate < ULONG_MAX) |
4648 | clk_set_rate_range_nolock(clk, min: 0, ULONG_MAX); |
4649 | |
4650 | owner = clk->core->owner; |
4651 | kref_put(kref: &clk->core->ref, release: __clk_release); |
4652 | |
4653 | clk_prepare_unlock(); |
4654 | |
4655 | module_put(module: owner); |
4656 | |
4657 | free_clk(clk); |
4658 | } |
4659 | |
4660 | /*** clk rate change notifiers ***/ |
4661 | |
4662 | /** |
4663 | * clk_notifier_register - add a clk rate change notifier |
4664 | * @clk: struct clk * to watch |
4665 | * @nb: struct notifier_block * with callback info |
4666 | * |
4667 | * Request notification when clk's rate changes. This uses an SRCU |
4668 | * notifier because we want it to block and notifier unregistrations are |
4669 | * uncommon. The callbacks associated with the notifier must not |
4670 | * re-enter into the clk framework by calling any top-level clk APIs; |
4671 | * this will cause a nested prepare_lock mutex. |
4672 | * |
4673 | * In all notification cases (pre, post and abort rate change) the original |
4674 | * clock rate is passed to the callback via struct clk_notifier_data.old_rate |
4675 | * and the new frequency is passed via struct clk_notifier_data.new_rate. |
4676 | * |
4677 | * clk_notifier_register() must be called from non-atomic context. |
4678 | * Returns -EINVAL if called with null arguments, -ENOMEM upon |
4679 | * allocation failure; otherwise, passes along the return value of |
4680 | * srcu_notifier_chain_register(). |
4681 | */ |
4682 | int clk_notifier_register(struct clk *clk, struct notifier_block *nb) |
4683 | { |
4684 | struct clk_notifier *cn; |
4685 | int ret = -ENOMEM; |
4686 | |
4687 | if (!clk || !nb) |
4688 | return -EINVAL; |
4689 | |
4690 | clk_prepare_lock(); |
4691 | |
4692 | /* search the list of notifiers for this clk */ |
4693 | list_for_each_entry(cn, &clk_notifier_list, node) |
4694 | if (cn->clk == clk) |
4695 | goto found; |
4696 | |
4697 | /* if clk wasn't in the notifier list, allocate new clk_notifier */ |
4698 | cn = kzalloc(size: sizeof(*cn), GFP_KERNEL); |
4699 | if (!cn) |
4700 | goto out; |
4701 | |
4702 | cn->clk = clk; |
4703 | srcu_init_notifier_head(nh: &cn->notifier_head); |
4704 | |
4705 | list_add(new: &cn->node, head: &clk_notifier_list); |
4706 | |
4707 | found: |
4708 | ret = srcu_notifier_chain_register(nh: &cn->notifier_head, nb); |
4709 | |
4710 | clk->core->notifier_count++; |
4711 | |
4712 | out: |
4713 | clk_prepare_unlock(); |
4714 | |
4715 | return ret; |
4716 | } |
4717 | EXPORT_SYMBOL_GPL(clk_notifier_register); |
4718 | |
4719 | /** |
4720 | * clk_notifier_unregister - remove a clk rate change notifier |
4721 | * @clk: struct clk * |
4722 | * @nb: struct notifier_block * with callback info |
4723 | * |
4724 | * Request no further notification for changes to 'clk' and frees memory |
4725 | * allocated in clk_notifier_register. |
4726 | * |
4727 | * Returns -EINVAL if called with null arguments; otherwise, passes |
4728 | * along the return value of srcu_notifier_chain_unregister(). |
4729 | */ |
4730 | int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb) |
4731 | { |
4732 | struct clk_notifier *cn; |
4733 | int ret = -ENOENT; |
4734 | |
4735 | if (!clk || !nb) |
4736 | return -EINVAL; |
4737 | |
4738 | clk_prepare_lock(); |
4739 | |
4740 | list_for_each_entry(cn, &clk_notifier_list, node) { |
4741 | if (cn->clk == clk) { |
4742 | ret = srcu_notifier_chain_unregister(nh: &cn->notifier_head, nb); |
4743 | |
4744 | clk->core->notifier_count--; |
4745 | |
4746 | /* XXX the notifier code should handle this better */ |
4747 | if (!cn->notifier_head.head) { |
4748 | srcu_cleanup_notifier_head(&cn->notifier_head); |
4749 | list_del(entry: &cn->node); |
4750 | kfree(objp: cn); |
4751 | } |
4752 | break; |
4753 | } |
4754 | } |
4755 | |
4756 | clk_prepare_unlock(); |
4757 | |
4758 | return ret; |
4759 | } |
4760 | EXPORT_SYMBOL_GPL(clk_notifier_unregister); |
4761 | |
4762 | struct clk_notifier_devres { |
4763 | struct clk *clk; |
4764 | struct notifier_block *nb; |
4765 | }; |
4766 | |
4767 | static void devm_clk_notifier_release(struct device *dev, void *res) |
4768 | { |
4769 | struct clk_notifier_devres *devres = res; |
4770 | |
4771 | clk_notifier_unregister(devres->clk, devres->nb); |
4772 | } |
4773 | |
4774 | int devm_clk_notifier_register(struct device *dev, struct clk *clk, |
4775 | struct notifier_block *nb) |
4776 | { |
4777 | struct clk_notifier_devres *devres; |
4778 | int ret; |
4779 | |
4780 | devres = devres_alloc(devm_clk_notifier_release, |
4781 | sizeof(*devres), GFP_KERNEL); |
4782 | |
4783 | if (!devres) |
4784 | return -ENOMEM; |
4785 | |
4786 | ret = clk_notifier_register(clk, nb); |
4787 | if (!ret) { |
4788 | devres->clk = clk; |
4789 | devres->nb = nb; |
4790 | devres_add(dev, res: devres); |
4791 | } else { |
4792 | devres_free(res: devres); |
4793 | } |
4794 | |
4795 | return ret; |
4796 | } |
4797 | EXPORT_SYMBOL_GPL(devm_clk_notifier_register); |
4798 | |
4799 | #ifdef CONFIG_OF |
4800 | static void clk_core_reparent_orphans(void) |
4801 | { |
4802 | clk_prepare_lock(); |
4803 | clk_core_reparent_orphans_nolock(); |
4804 | clk_prepare_unlock(); |
4805 | } |
4806 | |
4807 | /** |
4808 | * struct of_clk_provider - Clock provider registration structure |
4809 | * @link: Entry in global list of clock providers |
4810 | * @node: Pointer to device tree node of clock provider |
4811 | * @get: Get clock callback. Returns NULL or a struct clk for the |
4812 | * given clock specifier |
4813 | * @get_hw: Get clk_hw callback. Returns NULL, ERR_PTR or a |
4814 | * struct clk_hw for the given clock specifier |
4815 | * @data: context pointer to be passed into @get callback |
4816 | */ |
4817 | struct of_clk_provider { |
4818 | struct list_head link; |
4819 | |
4820 | struct device_node *node; |
4821 | struct clk *(*get)(struct of_phandle_args *clkspec, void *data); |
4822 | struct clk_hw *(*get_hw)(struct of_phandle_args *clkspec, void *data); |
4823 | void *data; |
4824 | }; |
4825 | |
4826 | extern struct of_device_id __clk_of_table; |
4827 | static const struct of_device_id __clk_of_table_sentinel |
4828 | __used __section("__clk_of_table_end" ); |
4829 | |
4830 | static LIST_HEAD(of_clk_providers); |
4831 | static DEFINE_MUTEX(of_clk_mutex); |
4832 | |
4833 | struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec, |
4834 | void *data) |
4835 | { |
4836 | return data; |
4837 | } |
4838 | EXPORT_SYMBOL_GPL(of_clk_src_simple_get); |
4839 | |
4840 | struct clk_hw *of_clk_hw_simple_get(struct of_phandle_args *clkspec, void *data) |
4841 | { |
4842 | return data; |
4843 | } |
4844 | EXPORT_SYMBOL_GPL(of_clk_hw_simple_get); |
4845 | |
4846 | struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data) |
4847 | { |
4848 | struct clk_onecell_data *clk_data = data; |
4849 | unsigned int idx = clkspec->args[0]; |
4850 | |
4851 | if (idx >= clk_data->clk_num) { |
4852 | pr_err("%s: invalid clock index %u\n" , __func__, idx); |
4853 | return ERR_PTR(error: -EINVAL); |
4854 | } |
4855 | |
4856 | return clk_data->clks[idx]; |
4857 | } |
4858 | EXPORT_SYMBOL_GPL(of_clk_src_onecell_get); |
4859 | |
4860 | struct clk_hw * |
4861 | of_clk_hw_onecell_get(struct of_phandle_args *clkspec, void *data) |
4862 | { |
4863 | struct clk_hw_onecell_data *hw_data = data; |
4864 | unsigned int idx = clkspec->args[0]; |
4865 | |
4866 | if (idx >= hw_data->num) { |
4867 | pr_err("%s: invalid index %u\n" , __func__, idx); |
4868 | return ERR_PTR(error: -EINVAL); |
4869 | } |
4870 | |
4871 | return hw_data->hws[idx]; |
4872 | } |
4873 | EXPORT_SYMBOL_GPL(of_clk_hw_onecell_get); |
4874 | |
4875 | /** |
4876 | * of_clk_add_provider() - Register a clock provider for a node |
4877 | * @np: Device node pointer associated with clock provider |
4878 | * @clk_src_get: callback for decoding clock |
4879 | * @data: context pointer for @clk_src_get callback. |
4880 | * |
4881 | * This function is *deprecated*. Use of_clk_add_hw_provider() instead. |
4882 | */ |
4883 | int of_clk_add_provider(struct device_node *np, |
4884 | struct clk *(*clk_src_get)(struct of_phandle_args *clkspec, |
4885 | void *data), |
4886 | void *data) |
4887 | { |
4888 | struct of_clk_provider *cp; |
4889 | int ret; |
4890 | |
4891 | if (!np) |
4892 | return 0; |
4893 | |
4894 | cp = kzalloc(size: sizeof(*cp), GFP_KERNEL); |
4895 | if (!cp) |
4896 | return -ENOMEM; |
4897 | |
4898 | cp->node = of_node_get(node: np); |
4899 | cp->data = data; |
4900 | cp->get = clk_src_get; |
4901 | |
4902 | mutex_lock(&of_clk_mutex); |
4903 | list_add(new: &cp->link, head: &of_clk_providers); |
4904 | mutex_unlock(lock: &of_clk_mutex); |
4905 | pr_debug("Added clock from %pOF\n" , np); |
4906 | |
4907 | clk_core_reparent_orphans(); |
4908 | |
4909 | ret = of_clk_set_defaults(node: np, clk_supplier: true); |
4910 | if (ret < 0) |
4911 | of_clk_del_provider(np); |
4912 | |
4913 | fwnode_dev_initialized(fwnode: &np->fwnode, initialized: true); |
4914 | |
4915 | return ret; |
4916 | } |
4917 | EXPORT_SYMBOL_GPL(of_clk_add_provider); |
4918 | |
4919 | /** |
4920 | * of_clk_add_hw_provider() - Register a clock provider for a node |
4921 | * @np: Device node pointer associated with clock provider |
4922 | * @get: callback for decoding clk_hw |
4923 | * @data: context pointer for @get callback. |
4924 | */ |
4925 | int of_clk_add_hw_provider(struct device_node *np, |
4926 | struct clk_hw *(*get)(struct of_phandle_args *clkspec, |
4927 | void *data), |
4928 | void *data) |
4929 | { |
4930 | struct of_clk_provider *cp; |
4931 | int ret; |
4932 | |
4933 | if (!np) |
4934 | return 0; |
4935 | |
4936 | cp = kzalloc(size: sizeof(*cp), GFP_KERNEL); |
4937 | if (!cp) |
4938 | return -ENOMEM; |
4939 | |
4940 | cp->node = of_node_get(node: np); |
4941 | cp->data = data; |
4942 | cp->get_hw = get; |
4943 | |
4944 | mutex_lock(&of_clk_mutex); |
4945 | list_add(new: &cp->link, head: &of_clk_providers); |
4946 | mutex_unlock(lock: &of_clk_mutex); |
4947 | pr_debug("Added clk_hw provider from %pOF\n" , np); |
4948 | |
4949 | clk_core_reparent_orphans(); |
4950 | |
4951 | ret = of_clk_set_defaults(node: np, clk_supplier: true); |
4952 | if (ret < 0) |
4953 | of_clk_del_provider(np); |
4954 | |
4955 | fwnode_dev_initialized(fwnode: &np->fwnode, initialized: true); |
4956 | |
4957 | return ret; |
4958 | } |
4959 | EXPORT_SYMBOL_GPL(of_clk_add_hw_provider); |
4960 | |
4961 | static void devm_of_clk_release_provider(struct device *dev, void *res) |
4962 | { |
4963 | of_clk_del_provider(np: *(struct device_node **)res); |
4964 | } |
4965 | |
4966 | /* |
4967 | * We allow a child device to use its parent device as the clock provider node |
4968 | * for cases like MFD sub-devices where the child device driver wants to use |
4969 | * devm_*() APIs but not list the device in DT as a sub-node. |
4970 | */ |
4971 | static struct device_node *get_clk_provider_node(struct device *dev) |
4972 | { |
4973 | struct device_node *np, *parent_np; |
4974 | |
4975 | np = dev->of_node; |
4976 | parent_np = dev->parent ? dev->parent->of_node : NULL; |
4977 | |
4978 | if (!of_property_present(np, propname: "#clock-cells" )) |
4979 | if (of_property_present(np: parent_np, propname: "#clock-cells" )) |
4980 | np = parent_np; |
4981 | |
4982 | return np; |
4983 | } |
4984 | |
4985 | /** |
4986 | * devm_of_clk_add_hw_provider() - Managed clk provider node registration |
4987 | * @dev: Device acting as the clock provider (used for DT node and lifetime) |
4988 | * @get: callback for decoding clk_hw |
4989 | * @data: context pointer for @get callback |
4990 | * |
4991 | * Registers clock provider for given device's node. If the device has no DT |
4992 | * node or if the device node lacks of clock provider information (#clock-cells) |
4993 | * then the parent device's node is scanned for this information. If parent node |
4994 | * has the #clock-cells then it is used in registration. Provider is |
4995 | * automatically released at device exit. |
4996 | * |
4997 | * Return: 0 on success or an errno on failure. |
4998 | */ |
4999 | int devm_of_clk_add_hw_provider(struct device *dev, |
5000 | struct clk_hw *(*get)(struct of_phandle_args *clkspec, |
5001 | void *data), |
5002 | void *data) |
5003 | { |
5004 | struct device_node **ptr, *np; |
5005 | int ret; |
5006 | |
5007 | ptr = devres_alloc(devm_of_clk_release_provider, sizeof(*ptr), |
5008 | GFP_KERNEL); |
5009 | if (!ptr) |
5010 | return -ENOMEM; |
5011 | |
5012 | np = get_clk_provider_node(dev); |
5013 | ret = of_clk_add_hw_provider(np, get, data); |
5014 | if (!ret) { |
5015 | *ptr = np; |
5016 | devres_add(dev, res: ptr); |
5017 | } else { |
5018 | devres_free(res: ptr); |
5019 | } |
5020 | |
5021 | return ret; |
5022 | } |
5023 | EXPORT_SYMBOL_GPL(devm_of_clk_add_hw_provider); |
5024 | |
5025 | /** |
5026 | * of_clk_del_provider() - Remove a previously registered clock provider |
5027 | * @np: Device node pointer associated with clock provider |
5028 | */ |
5029 | void of_clk_del_provider(struct device_node *np) |
5030 | { |
5031 | struct of_clk_provider *cp; |
5032 | |
5033 | if (!np) |
5034 | return; |
5035 | |
5036 | mutex_lock(&of_clk_mutex); |
5037 | list_for_each_entry(cp, &of_clk_providers, link) { |
5038 | if (cp->node == np) { |
5039 | list_del(entry: &cp->link); |
5040 | fwnode_dev_initialized(fwnode: &np->fwnode, initialized: false); |
5041 | of_node_put(node: cp->node); |
5042 | kfree(objp: cp); |
5043 | break; |
5044 | } |
5045 | } |
5046 | mutex_unlock(lock: &of_clk_mutex); |
5047 | } |
5048 | EXPORT_SYMBOL_GPL(of_clk_del_provider); |
5049 | |
5050 | /** |
5051 | * of_parse_clkspec() - Parse a DT clock specifier for a given device node |
5052 | * @np: device node to parse clock specifier from |
5053 | * @index: index of phandle to parse clock out of. If index < 0, @name is used |
5054 | * @name: clock name to find and parse. If name is NULL, the index is used |
5055 | * @out_args: Result of parsing the clock specifier |
5056 | * |
5057 | * Parses a device node's "clocks" and "clock-names" properties to find the |
5058 | * phandle and cells for the index or name that is desired. The resulting clock |
5059 | * specifier is placed into @out_args, or an errno is returned when there's a |
5060 | * parsing error. The @index argument is ignored if @name is non-NULL. |
5061 | * |
5062 | * Example: |
5063 | * |
5064 | * phandle1: clock-controller@1 { |
5065 | * #clock-cells = <2>; |
5066 | * } |
5067 | * |
5068 | * phandle2: clock-controller@2 { |
5069 | * #clock-cells = <1>; |
5070 | * } |
5071 | * |
5072 | * clock-consumer@3 { |
5073 | * clocks = <&phandle1 1 2 &phandle2 3>; |
5074 | * clock-names = "name1", "name2"; |
5075 | * } |
5076 | * |
5077 | * To get a device_node for `clock-controller@2' node you may call this |
5078 | * function a few different ways: |
5079 | * |
5080 | * of_parse_clkspec(clock-consumer@3, -1, "name2", &args); |
5081 | * of_parse_clkspec(clock-consumer@3, 1, NULL, &args); |
5082 | * of_parse_clkspec(clock-consumer@3, 1, "name2", &args); |
5083 | * |
5084 | * Return: 0 upon successfully parsing the clock specifier. Otherwise, -ENOENT |
5085 | * if @name is NULL or -EINVAL if @name is non-NULL and it can't be found in |
5086 | * the "clock-names" property of @np. |
5087 | */ |
5088 | static int of_parse_clkspec(const struct device_node *np, int index, |
5089 | const char *name, struct of_phandle_args *out_args) |
5090 | { |
5091 | int ret = -ENOENT; |
5092 | |
5093 | /* Walk up the tree of devices looking for a clock property that matches */ |
5094 | while (np) { |
5095 | /* |
5096 | * For named clocks, first look up the name in the |
5097 | * "clock-names" property. If it cannot be found, then index |
5098 | * will be an error code and of_parse_phandle_with_args() will |
5099 | * return -EINVAL. |
5100 | */ |
5101 | if (name) |
5102 | index = of_property_match_string(np, propname: "clock-names" , string: name); |
5103 | ret = of_parse_phandle_with_args(np, list_name: "clocks" , cells_name: "#clock-cells" , |
5104 | index, out_args); |
5105 | if (!ret) |
5106 | break; |
5107 | if (name && index >= 0) |
5108 | break; |
5109 | |
5110 | /* |
5111 | * No matching clock found on this node. If the parent node |
5112 | * has a "clock-ranges" property, then we can try one of its |
5113 | * clocks. |
5114 | */ |
5115 | np = np->parent; |
5116 | if (np && !of_get_property(node: np, name: "clock-ranges" , NULL)) |
5117 | break; |
5118 | index = 0; |
5119 | } |
5120 | |
5121 | return ret; |
5122 | } |
5123 | |
5124 | static struct clk_hw * |
5125 | __of_clk_get_hw_from_provider(struct of_clk_provider *provider, |
5126 | struct of_phandle_args *clkspec) |
5127 | { |
5128 | struct clk *clk; |
5129 | |
5130 | if (provider->get_hw) |
5131 | return provider->get_hw(clkspec, provider->data); |
5132 | |
5133 | clk = provider->get(clkspec, provider->data); |
5134 | if (IS_ERR(ptr: clk)) |
5135 | return ERR_CAST(ptr: clk); |
5136 | return __clk_get_hw(clk); |
5137 | } |
5138 | |
5139 | static struct clk_hw * |
5140 | of_clk_get_hw_from_clkspec(struct of_phandle_args *clkspec) |
5141 | { |
5142 | struct of_clk_provider *provider; |
5143 | struct clk_hw *hw = ERR_PTR(error: -EPROBE_DEFER); |
5144 | |
5145 | if (!clkspec) |
5146 | return ERR_PTR(error: -EINVAL); |
5147 | |
5148 | mutex_lock(&of_clk_mutex); |
5149 | list_for_each_entry(provider, &of_clk_providers, link) { |
5150 | if (provider->node == clkspec->np) { |
5151 | hw = __of_clk_get_hw_from_provider(provider, clkspec); |
5152 | if (!IS_ERR(ptr: hw)) |
5153 | break; |
5154 | } |
5155 | } |
5156 | mutex_unlock(lock: &of_clk_mutex); |
5157 | |
5158 | return hw; |
5159 | } |
5160 | |
5161 | /** |
5162 | * of_clk_get_from_provider() - Lookup a clock from a clock provider |
5163 | * @clkspec: pointer to a clock specifier data structure |
5164 | * |
5165 | * This function looks up a struct clk from the registered list of clock |
5166 | * providers, an input is a clock specifier data structure as returned |
5167 | * from the of_parse_phandle_with_args() function call. |
5168 | */ |
5169 | struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec) |
5170 | { |
5171 | struct clk_hw *hw = of_clk_get_hw_from_clkspec(clkspec); |
5172 | |
5173 | return clk_hw_create_clk(NULL, hw, NULL, con_id: __func__); |
5174 | } |
5175 | EXPORT_SYMBOL_GPL(of_clk_get_from_provider); |
5176 | |
5177 | struct clk_hw *of_clk_get_hw(struct device_node *np, int index, |
5178 | const char *con_id) |
5179 | { |
5180 | int ret; |
5181 | struct clk_hw *hw; |
5182 | struct of_phandle_args clkspec; |
5183 | |
5184 | ret = of_parse_clkspec(np, index, name: con_id, out_args: &clkspec); |
5185 | if (ret) |
5186 | return ERR_PTR(error: ret); |
5187 | |
5188 | hw = of_clk_get_hw_from_clkspec(clkspec: &clkspec); |
5189 | of_node_put(node: clkspec.np); |
5190 | |
5191 | return hw; |
5192 | } |
5193 | |
5194 | static struct clk *__of_clk_get(struct device_node *np, |
5195 | int index, const char *dev_id, |
5196 | const char *con_id) |
5197 | { |
5198 | struct clk_hw *hw = of_clk_get_hw(np, index, con_id); |
5199 | |
5200 | return clk_hw_create_clk(NULL, hw, dev_id, con_id); |
5201 | } |
5202 | |
5203 | struct clk *of_clk_get(struct device_node *np, int index) |
5204 | { |
5205 | return __of_clk_get(np, index, dev_id: np->full_name, NULL); |
5206 | } |
5207 | EXPORT_SYMBOL(of_clk_get); |
5208 | |
5209 | /** |
5210 | * of_clk_get_by_name() - Parse and lookup a clock referenced by a device node |
5211 | * @np: pointer to clock consumer node |
5212 | * @name: name of consumer's clock input, or NULL for the first clock reference |
5213 | * |
5214 | * This function parses the clocks and clock-names properties, |
5215 | * and uses them to look up the struct clk from the registered list of clock |
5216 | * providers. |
5217 | */ |
5218 | struct clk *of_clk_get_by_name(struct device_node *np, const char *name) |
5219 | { |
5220 | if (!np) |
5221 | return ERR_PTR(error: -ENOENT); |
5222 | |
5223 | return __of_clk_get(np, index: 0, dev_id: np->full_name, con_id: name); |
5224 | } |
5225 | EXPORT_SYMBOL(of_clk_get_by_name); |
5226 | |
5227 | /** |
5228 | * of_clk_get_parent_count() - Count the number of clocks a device node has |
5229 | * @np: device node to count |
5230 | * |
5231 | * Returns: The number of clocks that are possible parents of this node |
5232 | */ |
5233 | unsigned int of_clk_get_parent_count(const struct device_node *np) |
5234 | { |
5235 | int count; |
5236 | |
5237 | count = of_count_phandle_with_args(np, list_name: "clocks" , cells_name: "#clock-cells" ); |
5238 | if (count < 0) |
5239 | return 0; |
5240 | |
5241 | return count; |
5242 | } |
5243 | EXPORT_SYMBOL_GPL(of_clk_get_parent_count); |
5244 | |
5245 | const char *of_clk_get_parent_name(const struct device_node *np, int index) |
5246 | { |
5247 | struct of_phandle_args clkspec; |
5248 | struct property *prop; |
5249 | const char *clk_name; |
5250 | const __be32 *vp; |
5251 | u32 pv; |
5252 | int rc; |
5253 | int count; |
5254 | struct clk *clk; |
5255 | |
5256 | rc = of_parse_phandle_with_args(np, list_name: "clocks" , cells_name: "#clock-cells" , index, |
5257 | out_args: &clkspec); |
5258 | if (rc) |
5259 | return NULL; |
5260 | |
5261 | index = clkspec.args_count ? clkspec.args[0] : 0; |
5262 | count = 0; |
5263 | |
5264 | /* if there is an indices property, use it to transfer the index |
5265 | * specified into an array offset for the clock-output-names property. |
5266 | */ |
5267 | of_property_for_each_u32(clkspec.np, "clock-indices" , prop, vp, pv) { |
5268 | if (index == pv) { |
5269 | index = count; |
5270 | break; |
5271 | } |
5272 | count++; |
5273 | } |
5274 | /* We went off the end of 'clock-indices' without finding it */ |
5275 | if (prop && !vp) |
5276 | return NULL; |
5277 | |
5278 | if (of_property_read_string_index(np: clkspec.np, propname: "clock-output-names" , |
5279 | index, |
5280 | output: &clk_name) < 0) { |
5281 | /* |
5282 | * Best effort to get the name if the clock has been |
5283 | * registered with the framework. If the clock isn't |
5284 | * registered, we return the node name as the name of |
5285 | * the clock as long as #clock-cells = 0. |
5286 | */ |
5287 | clk = of_clk_get_from_provider(&clkspec); |
5288 | if (IS_ERR(ptr: clk)) { |
5289 | if (clkspec.args_count == 0) |
5290 | clk_name = clkspec.np->name; |
5291 | else |
5292 | clk_name = NULL; |
5293 | } else { |
5294 | clk_name = __clk_get_name(clk); |
5295 | clk_put(clk); |
5296 | } |
5297 | } |
5298 | |
5299 | |
5300 | of_node_put(node: clkspec.np); |
5301 | return clk_name; |
5302 | } |
5303 | EXPORT_SYMBOL_GPL(of_clk_get_parent_name); |
5304 | |
5305 | /** |
5306 | * of_clk_parent_fill() - Fill @parents with names of @np's parents and return |
5307 | * number of parents |
5308 | * @np: Device node pointer associated with clock provider |
5309 | * @parents: pointer to char array that hold the parents' names |
5310 | * @size: size of the @parents array |
5311 | * |
5312 | * Return: number of parents for the clock node. |
5313 | */ |
5314 | int of_clk_parent_fill(struct device_node *np, const char **parents, |
5315 | unsigned int size) |
5316 | { |
5317 | unsigned int i = 0; |
5318 | |
5319 | while (i < size && (parents[i] = of_clk_get_parent_name(np, i)) != NULL) |
5320 | i++; |
5321 | |
5322 | return i; |
5323 | } |
5324 | EXPORT_SYMBOL_GPL(of_clk_parent_fill); |
5325 | |
5326 | struct clock_provider { |
5327 | void (*clk_init_cb)(struct device_node *); |
5328 | struct device_node *np; |
5329 | struct list_head node; |
5330 | }; |
5331 | |
5332 | /* |
5333 | * This function looks for a parent clock. If there is one, then it |
5334 | * checks that the provider for this parent clock was initialized, in |
5335 | * this case the parent clock will be ready. |
5336 | */ |
5337 | static int parent_ready(struct device_node *np) |
5338 | { |
5339 | int i = 0; |
5340 | |
5341 | while (true) { |
5342 | struct clk *clk = of_clk_get(np, i); |
5343 | |
5344 | /* this parent is ready we can check the next one */ |
5345 | if (!IS_ERR(ptr: clk)) { |
5346 | clk_put(clk); |
5347 | i++; |
5348 | continue; |
5349 | } |
5350 | |
5351 | /* at least one parent is not ready, we exit now */ |
5352 | if (PTR_ERR(ptr: clk) == -EPROBE_DEFER) |
5353 | return 0; |
5354 | |
5355 | /* |
5356 | * Here we make assumption that the device tree is |
5357 | * written correctly. So an error means that there is |
5358 | * no more parent. As we didn't exit yet, then the |
5359 | * previous parent are ready. If there is no clock |
5360 | * parent, no need to wait for them, then we can |
5361 | * consider their absence as being ready |
5362 | */ |
5363 | return 1; |
5364 | } |
5365 | } |
5366 | |
5367 | /** |
5368 | * of_clk_detect_critical() - set CLK_IS_CRITICAL flag from Device Tree |
5369 | * @np: Device node pointer associated with clock provider |
5370 | * @index: clock index |
5371 | * @flags: pointer to top-level framework flags |
5372 | * |
5373 | * Detects if the clock-critical property exists and, if so, sets the |
5374 | * corresponding CLK_IS_CRITICAL flag. |
5375 | * |
5376 | * Do not use this function. It exists only for legacy Device Tree |
5377 | * bindings, such as the one-clock-per-node style that are outdated. |
5378 | * Those bindings typically put all clock data into .dts and the Linux |
5379 | * driver has no clock data, thus making it impossible to set this flag |
5380 | * correctly from the driver. Only those drivers may call |
5381 | * of_clk_detect_critical from their setup functions. |
5382 | * |
5383 | * Return: error code or zero on success |
5384 | */ |
5385 | int of_clk_detect_critical(struct device_node *np, int index, |
5386 | unsigned long *flags) |
5387 | { |
5388 | struct property *prop; |
5389 | const __be32 *cur; |
5390 | uint32_t idx; |
5391 | |
5392 | if (!np || !flags) |
5393 | return -EINVAL; |
5394 | |
5395 | of_property_for_each_u32(np, "clock-critical" , prop, cur, idx) |
5396 | if (index == idx) |
5397 | *flags |= CLK_IS_CRITICAL; |
5398 | |
5399 | return 0; |
5400 | } |
5401 | |
5402 | /** |
5403 | * of_clk_init() - Scan and init clock providers from the DT |
5404 | * @matches: array of compatible values and init functions for providers. |
5405 | * |
5406 | * This function scans the device tree for matching clock providers |
5407 | * and calls their initialization functions. It also does it by trying |
5408 | * to follow the dependencies. |
5409 | */ |
5410 | void __init of_clk_init(const struct of_device_id *matches) |
5411 | { |
5412 | const struct of_device_id *match; |
5413 | struct device_node *np; |
5414 | struct clock_provider *clk_provider, *next; |
5415 | bool is_init_done; |
5416 | bool force = false; |
5417 | LIST_HEAD(clk_provider_list); |
5418 | |
5419 | if (!matches) |
5420 | matches = &__clk_of_table; |
5421 | |
5422 | /* First prepare the list of the clocks providers */ |
5423 | for_each_matching_node_and_match(np, matches, &match) { |
5424 | struct clock_provider *parent; |
5425 | |
5426 | if (!of_device_is_available(device: np)) |
5427 | continue; |
5428 | |
5429 | parent = kzalloc(size: sizeof(*parent), GFP_KERNEL); |
5430 | if (!parent) { |
5431 | list_for_each_entry_safe(clk_provider, next, |
5432 | &clk_provider_list, node) { |
5433 | list_del(entry: &clk_provider->node); |
5434 | of_node_put(node: clk_provider->np); |
5435 | kfree(objp: clk_provider); |
5436 | } |
5437 | of_node_put(node: np); |
5438 | return; |
5439 | } |
5440 | |
5441 | parent->clk_init_cb = match->data; |
5442 | parent->np = of_node_get(node: np); |
5443 | list_add_tail(new: &parent->node, head: &clk_provider_list); |
5444 | } |
5445 | |
5446 | while (!list_empty(head: &clk_provider_list)) { |
5447 | is_init_done = false; |
5448 | list_for_each_entry_safe(clk_provider, next, |
5449 | &clk_provider_list, node) { |
5450 | if (force || parent_ready(np: clk_provider->np)) { |
5451 | |
5452 | /* Don't populate platform devices */ |
5453 | of_node_set_flag(n: clk_provider->np, |
5454 | OF_POPULATED); |
5455 | |
5456 | clk_provider->clk_init_cb(clk_provider->np); |
5457 | of_clk_set_defaults(node: clk_provider->np, clk_supplier: true); |
5458 | |
5459 | list_del(entry: &clk_provider->node); |
5460 | of_node_put(node: clk_provider->np); |
5461 | kfree(objp: clk_provider); |
5462 | is_init_done = true; |
5463 | } |
5464 | } |
5465 | |
5466 | /* |
5467 | * We didn't manage to initialize any of the |
5468 | * remaining providers during the last loop, so now we |
5469 | * initialize all the remaining ones unconditionally |
5470 | * in case the clock parent was not mandatory |
5471 | */ |
5472 | if (!is_init_done) |
5473 | force = true; |
5474 | } |
5475 | } |
5476 | #endif |
5477 | |