1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
4 */
5
6#include <linux/clk-provider.h>
7#include <linux/clkdev.h>
8#include <linux/clk/at91_pmc.h>
9#include <linux/delay.h>
10#include <linux/mfd/syscon.h>
11#include <linux/regmap.h>
12
13#include "pmc.h"
14
15#define SLOW_CLOCK_FREQ 32768
16#define MAINF_DIV 16
17#define MAINFRDY_TIMEOUT (((MAINF_DIV + 1) * USEC_PER_SEC) / \
18 SLOW_CLOCK_FREQ)
19#define MAINF_LOOP_MIN_WAIT (USEC_PER_SEC / SLOW_CLOCK_FREQ)
20#define MAINF_LOOP_MAX_WAIT MAINFRDY_TIMEOUT
21
22#define MOR_KEY_MASK (0xff << 16)
23
24#define clk_main_parent_select(s) (((s) & \
25 (AT91_PMC_MOSCEN | \
26 AT91_PMC_OSCBYPASS)) ? 1 : 0)
27
28struct clk_main_osc {
29 struct clk_hw hw;
30 struct regmap *regmap;
31 struct at91_clk_pms pms;
32};
33
34#define to_clk_main_osc(hw) container_of(hw, struct clk_main_osc, hw)
35
36struct clk_main_rc_osc {
37 struct clk_hw hw;
38 struct regmap *regmap;
39 unsigned long frequency;
40 unsigned long accuracy;
41 struct at91_clk_pms pms;
42};
43
44#define to_clk_main_rc_osc(hw) container_of(hw, struct clk_main_rc_osc, hw)
45
46struct clk_rm9200_main {
47 struct clk_hw hw;
48 struct regmap *regmap;
49};
50
51#define to_clk_rm9200_main(hw) container_of(hw, struct clk_rm9200_main, hw)
52
53struct clk_sam9x5_main {
54 struct clk_hw hw;
55 struct regmap *regmap;
56 struct at91_clk_pms pms;
57 u8 parent;
58};
59
60#define to_clk_sam9x5_main(hw) container_of(hw, struct clk_sam9x5_main, hw)
61
62static inline bool clk_main_osc_ready(struct regmap *regmap)
63{
64 unsigned int status;
65
66 regmap_read(map: regmap, AT91_PMC_SR, val: &status);
67
68 return status & AT91_PMC_MOSCS;
69}
70
71static int clk_main_osc_prepare(struct clk_hw *hw)
72{
73 struct clk_main_osc *osc = to_clk_main_osc(hw);
74 struct regmap *regmap = osc->regmap;
75 u32 tmp;
76
77 regmap_read(map: regmap, AT91_CKGR_MOR, val: &tmp);
78 tmp &= ~MOR_KEY_MASK;
79
80 if (tmp & AT91_PMC_OSCBYPASS)
81 return 0;
82
83 if (!(tmp & AT91_PMC_MOSCEN)) {
84 tmp |= AT91_PMC_MOSCEN | AT91_PMC_KEY;
85 regmap_write(map: regmap, AT91_CKGR_MOR, val: tmp);
86 }
87
88 while (!clk_main_osc_ready(regmap))
89 cpu_relax();
90
91 return 0;
92}
93
94static void clk_main_osc_unprepare(struct clk_hw *hw)
95{
96 struct clk_main_osc *osc = to_clk_main_osc(hw);
97 struct regmap *regmap = osc->regmap;
98 u32 tmp;
99
100 regmap_read(map: regmap, AT91_CKGR_MOR, val: &tmp);
101 if (tmp & AT91_PMC_OSCBYPASS)
102 return;
103
104 if (!(tmp & AT91_PMC_MOSCEN))
105 return;
106
107 tmp &= ~(AT91_PMC_KEY | AT91_PMC_MOSCEN);
108 regmap_write(map: regmap, AT91_CKGR_MOR, val: tmp | AT91_PMC_KEY);
109}
110
111static int clk_main_osc_is_prepared(struct clk_hw *hw)
112{
113 struct clk_main_osc *osc = to_clk_main_osc(hw);
114 struct regmap *regmap = osc->regmap;
115 u32 tmp, status;
116
117 regmap_read(map: regmap, AT91_CKGR_MOR, val: &tmp);
118 if (tmp & AT91_PMC_OSCBYPASS)
119 return 1;
120
121 regmap_read(map: regmap, AT91_PMC_SR, val: &status);
122
123 return (status & AT91_PMC_MOSCS) && clk_main_parent_select(tmp);
124}
125
126static int clk_main_osc_save_context(struct clk_hw *hw)
127{
128 struct clk_main_osc *osc = to_clk_main_osc(hw);
129
130 osc->pms.status = clk_main_osc_is_prepared(hw);
131
132 return 0;
133}
134
135static void clk_main_osc_restore_context(struct clk_hw *hw)
136{
137 struct clk_main_osc *osc = to_clk_main_osc(hw);
138
139 if (osc->pms.status)
140 clk_main_osc_prepare(hw);
141}
142
143static const struct clk_ops main_osc_ops = {
144 .prepare = clk_main_osc_prepare,
145 .unprepare = clk_main_osc_unprepare,
146 .is_prepared = clk_main_osc_is_prepared,
147 .save_context = clk_main_osc_save_context,
148 .restore_context = clk_main_osc_restore_context,
149};
150
151struct clk_hw * __init
152at91_clk_register_main_osc(struct regmap *regmap,
153 const char *name,
154 const char *parent_name,
155 struct clk_parent_data *parent_data,
156 bool bypass)
157{
158 struct clk_main_osc *osc;
159 struct clk_init_data init = {};
160 struct clk_hw *hw;
161 int ret;
162
163 if (!name || !(parent_name || parent_data))
164 return ERR_PTR(error: -EINVAL);
165
166 osc = kzalloc(size: sizeof(*osc), GFP_KERNEL);
167 if (!osc)
168 return ERR_PTR(error: -ENOMEM);
169
170 init.name = name;
171 init.ops = &main_osc_ops;
172 if (parent_data)
173 init.parent_data = (const struct clk_parent_data *)parent_data;
174 else
175 init.parent_names = &parent_name;
176 init.num_parents = 1;
177 init.flags = CLK_IGNORE_UNUSED;
178
179 osc->hw.init = &init;
180 osc->regmap = regmap;
181
182 if (bypass)
183 regmap_update_bits(map: regmap,
184 AT91_CKGR_MOR, MOR_KEY_MASK |
185 AT91_PMC_OSCBYPASS,
186 AT91_PMC_OSCBYPASS | AT91_PMC_KEY);
187
188 hw = &osc->hw;
189 ret = clk_hw_register(NULL, hw: &osc->hw);
190 if (ret) {
191 kfree(objp: osc);
192 hw = ERR_PTR(error: ret);
193 }
194
195 return hw;
196}
197
198static bool clk_main_rc_osc_ready(struct regmap *regmap)
199{
200 unsigned int status;
201
202 regmap_read(map: regmap, AT91_PMC_SR, val: &status);
203
204 return !!(status & AT91_PMC_MOSCRCS);
205}
206
207static int clk_main_rc_osc_prepare(struct clk_hw *hw)
208{
209 struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
210 struct regmap *regmap = osc->regmap;
211 unsigned int mor;
212
213 regmap_read(map: regmap, AT91_CKGR_MOR, val: &mor);
214
215 if (!(mor & AT91_PMC_MOSCRCEN))
216 regmap_update_bits(map: regmap, AT91_CKGR_MOR,
217 MOR_KEY_MASK | AT91_PMC_MOSCRCEN,
218 AT91_PMC_MOSCRCEN | AT91_PMC_KEY);
219
220 while (!clk_main_rc_osc_ready(regmap))
221 cpu_relax();
222
223 return 0;
224}
225
226static void clk_main_rc_osc_unprepare(struct clk_hw *hw)
227{
228 struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
229 struct regmap *regmap = osc->regmap;
230 unsigned int mor;
231
232 regmap_read(map: regmap, AT91_CKGR_MOR, val: &mor);
233
234 if (!(mor & AT91_PMC_MOSCRCEN))
235 return;
236
237 regmap_update_bits(map: regmap, AT91_CKGR_MOR,
238 MOR_KEY_MASK | AT91_PMC_MOSCRCEN, AT91_PMC_KEY);
239}
240
241static int clk_main_rc_osc_is_prepared(struct clk_hw *hw)
242{
243 struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
244 struct regmap *regmap = osc->regmap;
245 unsigned int mor, status;
246
247 regmap_read(map: regmap, AT91_CKGR_MOR, val: &mor);
248 regmap_read(map: regmap, AT91_PMC_SR, val: &status);
249
250 return (mor & AT91_PMC_MOSCRCEN) && (status & AT91_PMC_MOSCRCS);
251}
252
253static unsigned long clk_main_rc_osc_recalc_rate(struct clk_hw *hw,
254 unsigned long parent_rate)
255{
256 struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
257
258 return osc->frequency;
259}
260
261static unsigned long clk_main_rc_osc_recalc_accuracy(struct clk_hw *hw,
262 unsigned long parent_acc)
263{
264 struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
265
266 return osc->accuracy;
267}
268
269static int clk_main_rc_osc_save_context(struct clk_hw *hw)
270{
271 struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
272
273 osc->pms.status = clk_main_rc_osc_is_prepared(hw);
274
275 return 0;
276}
277
278static void clk_main_rc_osc_restore_context(struct clk_hw *hw)
279{
280 struct clk_main_rc_osc *osc = to_clk_main_rc_osc(hw);
281
282 if (osc->pms.status)
283 clk_main_rc_osc_prepare(hw);
284}
285
286static const struct clk_ops main_rc_osc_ops = {
287 .prepare = clk_main_rc_osc_prepare,
288 .unprepare = clk_main_rc_osc_unprepare,
289 .is_prepared = clk_main_rc_osc_is_prepared,
290 .recalc_rate = clk_main_rc_osc_recalc_rate,
291 .recalc_accuracy = clk_main_rc_osc_recalc_accuracy,
292 .save_context = clk_main_rc_osc_save_context,
293 .restore_context = clk_main_rc_osc_restore_context,
294};
295
296struct clk_hw * __init
297at91_clk_register_main_rc_osc(struct regmap *regmap,
298 const char *name,
299 u32 frequency, u32 accuracy)
300{
301 struct clk_main_rc_osc *osc;
302 struct clk_init_data init;
303 struct clk_hw *hw;
304 int ret;
305
306 if (!name || !frequency)
307 return ERR_PTR(error: -EINVAL);
308
309 osc = kzalloc(size: sizeof(*osc), GFP_KERNEL);
310 if (!osc)
311 return ERR_PTR(error: -ENOMEM);
312
313 init.name = name;
314 init.ops = &main_rc_osc_ops;
315 init.parent_names = NULL;
316 init.num_parents = 0;
317 init.flags = CLK_IGNORE_UNUSED;
318
319 osc->hw.init = &init;
320 osc->regmap = regmap;
321 osc->frequency = frequency;
322 osc->accuracy = accuracy;
323
324 hw = &osc->hw;
325 ret = clk_hw_register(NULL, hw);
326 if (ret) {
327 kfree(objp: osc);
328 hw = ERR_PTR(error: ret);
329 }
330
331 return hw;
332}
333
334static int clk_main_probe_frequency(struct regmap *regmap)
335{
336 unsigned long prep_time, timeout;
337 unsigned int mcfr;
338
339 timeout = jiffies + usecs_to_jiffies(MAINFRDY_TIMEOUT);
340 do {
341 prep_time = jiffies;
342 regmap_read(map: regmap, AT91_CKGR_MCFR, val: &mcfr);
343 if (mcfr & AT91_PMC_MAINRDY)
344 return 0;
345 if (system_state < SYSTEM_RUNNING)
346 udelay(MAINF_LOOP_MIN_WAIT);
347 else
348 usleep_range(MAINF_LOOP_MIN_WAIT, MAINF_LOOP_MAX_WAIT);
349 } while (time_before(prep_time, timeout));
350
351 return -ETIMEDOUT;
352}
353
354static unsigned long clk_main_recalc_rate(struct regmap *regmap,
355 unsigned long parent_rate)
356{
357 unsigned int mcfr;
358
359 if (parent_rate)
360 return parent_rate;
361
362 pr_warn("Main crystal frequency not set, using approximate value\n");
363 regmap_read(map: regmap, AT91_CKGR_MCFR, val: &mcfr);
364 if (!(mcfr & AT91_PMC_MAINRDY))
365 return 0;
366
367 return ((mcfr & AT91_PMC_MAINF) * SLOW_CLOCK_FREQ) / MAINF_DIV;
368}
369
370static int clk_rm9200_main_prepare(struct clk_hw *hw)
371{
372 struct clk_rm9200_main *clkmain = to_clk_rm9200_main(hw);
373
374 return clk_main_probe_frequency(regmap: clkmain->regmap);
375}
376
377static int clk_rm9200_main_is_prepared(struct clk_hw *hw)
378{
379 struct clk_rm9200_main *clkmain = to_clk_rm9200_main(hw);
380 unsigned int status;
381
382 regmap_read(map: clkmain->regmap, AT91_CKGR_MCFR, val: &status);
383
384 return !!(status & AT91_PMC_MAINRDY);
385}
386
387static unsigned long clk_rm9200_main_recalc_rate(struct clk_hw *hw,
388 unsigned long parent_rate)
389{
390 struct clk_rm9200_main *clkmain = to_clk_rm9200_main(hw);
391
392 return clk_main_recalc_rate(regmap: clkmain->regmap, parent_rate);
393}
394
395static const struct clk_ops rm9200_main_ops = {
396 .prepare = clk_rm9200_main_prepare,
397 .is_prepared = clk_rm9200_main_is_prepared,
398 .recalc_rate = clk_rm9200_main_recalc_rate,
399};
400
401struct clk_hw * __init
402at91_clk_register_rm9200_main(struct regmap *regmap,
403 const char *name,
404 const char *parent_name,
405 struct clk_hw *parent_hw)
406{
407 struct clk_rm9200_main *clkmain;
408 struct clk_init_data init = {};
409 struct clk_hw *hw;
410 int ret;
411
412 if (!name)
413 return ERR_PTR(error: -EINVAL);
414
415 if (!(parent_name || parent_hw))
416 return ERR_PTR(error: -EINVAL);
417
418 clkmain = kzalloc(size: sizeof(*clkmain), GFP_KERNEL);
419 if (!clkmain)
420 return ERR_PTR(error: -ENOMEM);
421
422 init.name = name;
423 init.ops = &rm9200_main_ops;
424 if (parent_hw)
425 init.parent_hws = (const struct clk_hw **)&parent_hw;
426 else
427 init.parent_names = &parent_name;
428 init.num_parents = 1;
429 init.flags = 0;
430
431 clkmain->hw.init = &init;
432 clkmain->regmap = regmap;
433
434 hw = &clkmain->hw;
435 ret = clk_hw_register(NULL, hw: &clkmain->hw);
436 if (ret) {
437 kfree(objp: clkmain);
438 hw = ERR_PTR(error: ret);
439 }
440
441 return hw;
442}
443
444static inline bool clk_sam9x5_main_ready(struct regmap *regmap)
445{
446 unsigned int status;
447
448 regmap_read(map: regmap, AT91_PMC_SR, val: &status);
449
450 return !!(status & AT91_PMC_MOSCSELS);
451}
452
453static int clk_sam9x5_main_prepare(struct clk_hw *hw)
454{
455 struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
456 struct regmap *regmap = clkmain->regmap;
457
458 while (!clk_sam9x5_main_ready(regmap))
459 cpu_relax();
460
461 return clk_main_probe_frequency(regmap);
462}
463
464static int clk_sam9x5_main_is_prepared(struct clk_hw *hw)
465{
466 struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
467
468 return clk_sam9x5_main_ready(regmap: clkmain->regmap);
469}
470
471static unsigned long clk_sam9x5_main_recalc_rate(struct clk_hw *hw,
472 unsigned long parent_rate)
473{
474 struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
475
476 return clk_main_recalc_rate(regmap: clkmain->regmap, parent_rate);
477}
478
479static int clk_sam9x5_main_set_parent(struct clk_hw *hw, u8 index)
480{
481 struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
482 struct regmap *regmap = clkmain->regmap;
483 unsigned int tmp;
484
485 if (index > 1)
486 return -EINVAL;
487
488 regmap_read(map: regmap, AT91_CKGR_MOR, val: &tmp);
489
490 if (index && !(tmp & AT91_PMC_MOSCSEL))
491 tmp = AT91_PMC_MOSCSEL;
492 else if (!index && (tmp & AT91_PMC_MOSCSEL))
493 tmp = 0;
494 else
495 return 0;
496
497 regmap_update_bits(map: regmap, AT91_CKGR_MOR,
498 AT91_PMC_MOSCSEL | MOR_KEY_MASK,
499 val: tmp | AT91_PMC_KEY);
500
501 while (!clk_sam9x5_main_ready(regmap))
502 cpu_relax();
503
504 return 0;
505}
506
507static u8 clk_sam9x5_main_get_parent(struct clk_hw *hw)
508{
509 struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
510 unsigned int status;
511
512 regmap_read(map: clkmain->regmap, AT91_CKGR_MOR, val: &status);
513
514 return clk_main_parent_select(status);
515}
516
517static int clk_sam9x5_main_save_context(struct clk_hw *hw)
518{
519 struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
520
521 clkmain->pms.status = clk_main_rc_osc_is_prepared(hw: &clkmain->hw);
522 clkmain->pms.parent = clk_sam9x5_main_get_parent(hw: &clkmain->hw);
523
524 return 0;
525}
526
527static void clk_sam9x5_main_restore_context(struct clk_hw *hw)
528{
529 struct clk_sam9x5_main *clkmain = to_clk_sam9x5_main(hw);
530 int ret;
531
532 ret = clk_sam9x5_main_set_parent(hw, index: clkmain->pms.parent);
533 if (ret)
534 return;
535
536 if (clkmain->pms.status)
537 clk_sam9x5_main_prepare(hw);
538}
539
540static const struct clk_ops sam9x5_main_ops = {
541 .prepare = clk_sam9x5_main_prepare,
542 .is_prepared = clk_sam9x5_main_is_prepared,
543 .recalc_rate = clk_sam9x5_main_recalc_rate,
544 .determine_rate = clk_hw_determine_rate_no_reparent,
545 .set_parent = clk_sam9x5_main_set_parent,
546 .get_parent = clk_sam9x5_main_get_parent,
547 .save_context = clk_sam9x5_main_save_context,
548 .restore_context = clk_sam9x5_main_restore_context,
549};
550
551struct clk_hw * __init
552at91_clk_register_sam9x5_main(struct regmap *regmap,
553 const char *name,
554 const char **parent_names,
555 struct clk_hw **parent_hws,
556 int num_parents)
557{
558 struct clk_sam9x5_main *clkmain;
559 struct clk_init_data init = {};
560 unsigned int status;
561 struct clk_hw *hw;
562 int ret;
563
564 if (!name)
565 return ERR_PTR(error: -EINVAL);
566
567 if (!(parent_hws || parent_names) || !num_parents)
568 return ERR_PTR(error: -EINVAL);
569
570 clkmain = kzalloc(size: sizeof(*clkmain), GFP_KERNEL);
571 if (!clkmain)
572 return ERR_PTR(error: -ENOMEM);
573
574 init.name = name;
575 init.ops = &sam9x5_main_ops;
576 if (parent_hws)
577 init.parent_hws = (const struct clk_hw **)parent_hws;
578 else
579 init.parent_names = parent_names;
580 init.num_parents = num_parents;
581 init.flags = CLK_SET_PARENT_GATE;
582
583 clkmain->hw.init = &init;
584 clkmain->regmap = regmap;
585 regmap_read(map: clkmain->regmap, AT91_CKGR_MOR, val: &status);
586 clkmain->parent = clk_main_parent_select(status);
587
588 hw = &clkmain->hw;
589 ret = clk_hw_register(NULL, hw: &clkmain->hw);
590 if (ret) {
591 kfree(objp: clkmain);
592 hw = ERR_PTR(error: ret);
593 }
594
595 return hw;
596}
597

source code of linux/drivers/clk/at91/clk-main.c