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36ca09be D |
1 | /* |
2 | * MPIC timer driver | |
3 | * | |
4 | * Copyright 2013 Freescale Semiconductor, Inc. | |
5 | * Author: Dongsheng Wang <Dongsheng.Wang@freescale.com> | |
6 | * Li Yang <leoli@freescale.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify it | |
9 | * under the terms of the GNU General Public License as published by the | |
10 | * Free Software Foundation; either version 2 of the License, or (at your | |
11 | * option) any later version. | |
12 | */ | |
13 | ||
14 | #include <linux/kernel.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/module.h> | |
17 | #include <linux/errno.h> | |
18 | #include <linux/mm.h> | |
19 | #include <linux/interrupt.h> | |
20 | #include <linux/slab.h> | |
21 | #include <linux/of.h> | |
26a2056e | 22 | #include <linux/of_address.h> |
36ca09be | 23 | #include <linux/of_device.h> |
26a2056e | 24 | #include <linux/of_irq.h> |
36ca09be D |
25 | #include <linux/syscore_ops.h> |
26 | #include <sysdev/fsl_soc.h> | |
27 | #include <asm/io.h> | |
28 | ||
29 | #include <asm/mpic_timer.h> | |
30 | ||
31 | #define FSL_GLOBAL_TIMER 0x1 | |
32 | ||
33 | /* Clock Ratio | |
34 | * Divide by 64 0x00000300 | |
35 | * Divide by 32 0x00000200 | |
36 | * Divide by 16 0x00000100 | |
37 | * Divide by 8 0x00000000 (Hardware default div) | |
38 | */ | |
39 | #define MPIC_TIMER_TCR_CLKDIV 0x00000300 | |
40 | ||
41 | #define MPIC_TIMER_TCR_ROVR_OFFSET 24 | |
42 | ||
43 | #define TIMER_STOP 0x80000000 | |
0fd79588 | 44 | #define GTCCR_TOG 0x80000000 |
36ca09be D |
45 | #define TIMERS_PER_GROUP 4 |
46 | #define MAX_TICKS (~0U >> 1) | |
47 | #define MAX_TICKS_CASCADE (~0U) | |
48 | #define TIMER_OFFSET(num) (1 << (TIMERS_PER_GROUP - 1 - num)) | |
49 | ||
36ca09be D |
50 | struct timer_regs { |
51 | u32 gtccr; | |
52 | u32 res0[3]; | |
53 | u32 gtbcr; | |
54 | u32 res1[3]; | |
55 | u32 gtvpr; | |
56 | u32 res2[3]; | |
57 | u32 gtdr; | |
58 | u32 res3[3]; | |
59 | }; | |
60 | ||
61 | struct cascade_priv { | |
62 | u32 tcr_value; /* TCR register: CASC & ROVR value */ | |
63 | unsigned int cascade_map; /* cascade map */ | |
64 | unsigned int timer_num; /* cascade control timer */ | |
65 | }; | |
66 | ||
67 | struct timer_group_priv { | |
68 | struct timer_regs __iomem *regs; | |
69 | struct mpic_timer timer[TIMERS_PER_GROUP]; | |
70 | struct list_head node; | |
71 | unsigned int timerfreq; | |
72 | unsigned int idle; | |
73 | unsigned int flags; | |
74 | spinlock_t lock; | |
75 | void __iomem *group_tcr; | |
76 | }; | |
77 | ||
78 | static struct cascade_priv cascade_timer[] = { | |
79 | /* cascade timer 0 and 1 */ | |
80 | {0x1, 0xc, 0x1}, | |
81 | /* cascade timer 1 and 2 */ | |
82 | {0x2, 0x6, 0x2}, | |
83 | /* cascade timer 2 and 3 */ | |
84 | {0x4, 0x3, 0x3} | |
85 | }; | |
86 | ||
87 | static LIST_HEAD(timer_group_list); | |
88 | ||
89 | static void convert_ticks_to_time(struct timer_group_priv *priv, | |
11ed8c55 | 90 | const u64 ticks, time64_t *time) |
36ca09be | 91 | { |
11ed8c55 | 92 | *time = (u64)div_u64(ticks, priv->timerfreq); |
36ca09be D |
93 | } |
94 | ||
95 | /* the time set by the user is converted to "ticks" */ | |
96 | static int convert_time_to_ticks(struct timer_group_priv *priv, | |
11ed8c55 | 97 | time64_t time, u64 *ticks) |
36ca09be D |
98 | { |
99 | u64 max_value; /* prevent u64 overflow */ | |
36ca09be D |
100 | |
101 | max_value = div_u64(ULLONG_MAX, priv->timerfreq); | |
102 | ||
11ed8c55 | 103 | if (time > max_value) |
36ca09be D |
104 | return -EINVAL; |
105 | ||
11ed8c55 | 106 | *ticks = (u64)time * (u64)priv->timerfreq; |
36ca09be D |
107 | |
108 | return 0; | |
109 | } | |
110 | ||
111 | /* detect whether there is a cascade timer available */ | |
112 | static struct mpic_timer *detect_idle_cascade_timer( | |
113 | struct timer_group_priv *priv) | |
114 | { | |
115 | struct cascade_priv *casc_priv; | |
116 | unsigned int map; | |
117 | unsigned int array_size = ARRAY_SIZE(cascade_timer); | |
118 | unsigned int num; | |
119 | unsigned int i; | |
120 | unsigned long flags; | |
121 | ||
122 | casc_priv = cascade_timer; | |
123 | for (i = 0; i < array_size; i++) { | |
124 | spin_lock_irqsave(&priv->lock, flags); | |
125 | map = casc_priv->cascade_map & priv->idle; | |
126 | if (map == casc_priv->cascade_map) { | |
127 | num = casc_priv->timer_num; | |
128 | priv->timer[num].cascade_handle = casc_priv; | |
129 | ||
130 | /* set timer busy */ | |
131 | priv->idle &= ~casc_priv->cascade_map; | |
132 | spin_unlock_irqrestore(&priv->lock, flags); | |
133 | return &priv->timer[num]; | |
134 | } | |
135 | spin_unlock_irqrestore(&priv->lock, flags); | |
136 | casc_priv++; | |
137 | } | |
138 | ||
139 | return NULL; | |
140 | } | |
141 | ||
142 | static int set_cascade_timer(struct timer_group_priv *priv, u64 ticks, | |
143 | unsigned int num) | |
144 | { | |
145 | struct cascade_priv *casc_priv; | |
146 | u32 tcr; | |
147 | u32 tmp_ticks; | |
148 | u32 rem_ticks; | |
149 | ||
150 | /* set group tcr reg for cascade */ | |
151 | casc_priv = priv->timer[num].cascade_handle; | |
152 | if (!casc_priv) | |
153 | return -EINVAL; | |
154 | ||
155 | tcr = casc_priv->tcr_value | | |
156 | (casc_priv->tcr_value << MPIC_TIMER_TCR_ROVR_OFFSET); | |
157 | setbits32(priv->group_tcr, tcr); | |
158 | ||
159 | tmp_ticks = div_u64_rem(ticks, MAX_TICKS_CASCADE, &rem_ticks); | |
160 | ||
161 | out_be32(&priv->regs[num].gtccr, 0); | |
162 | out_be32(&priv->regs[num].gtbcr, tmp_ticks | TIMER_STOP); | |
163 | ||
164 | out_be32(&priv->regs[num - 1].gtccr, 0); | |
165 | out_be32(&priv->regs[num - 1].gtbcr, rem_ticks); | |
166 | ||
167 | return 0; | |
168 | } | |
169 | ||
170 | static struct mpic_timer *get_cascade_timer(struct timer_group_priv *priv, | |
171 | u64 ticks) | |
172 | { | |
173 | struct mpic_timer *allocated_timer; | |
174 | ||
175 | /* Two cascade timers: Support the maximum time */ | |
176 | const u64 max_ticks = (u64)MAX_TICKS * (u64)MAX_TICKS_CASCADE; | |
177 | int ret; | |
178 | ||
179 | if (ticks > max_ticks) | |
180 | return NULL; | |
181 | ||
182 | /* detect idle timer */ | |
183 | allocated_timer = detect_idle_cascade_timer(priv); | |
184 | if (!allocated_timer) | |
185 | return NULL; | |
186 | ||
187 | /* set ticks to timer */ | |
188 | ret = set_cascade_timer(priv, ticks, allocated_timer->num); | |
189 | if (ret < 0) | |
190 | return NULL; | |
191 | ||
192 | return allocated_timer; | |
193 | } | |
194 | ||
11ed8c55 | 195 | static struct mpic_timer *get_timer(time64_t time) |
36ca09be D |
196 | { |
197 | struct timer_group_priv *priv; | |
198 | struct mpic_timer *timer; | |
199 | ||
200 | u64 ticks; | |
201 | unsigned int num; | |
202 | unsigned int i; | |
203 | unsigned long flags; | |
204 | int ret; | |
205 | ||
206 | list_for_each_entry(priv, &timer_group_list, node) { | |
207 | ret = convert_time_to_ticks(priv, time, &ticks); | |
208 | if (ret < 0) | |
209 | return NULL; | |
210 | ||
211 | if (ticks > MAX_TICKS) { | |
212 | if (!(priv->flags & FSL_GLOBAL_TIMER)) | |
213 | return NULL; | |
214 | ||
215 | timer = get_cascade_timer(priv, ticks); | |
216 | if (!timer) | |
217 | continue; | |
218 | ||
219 | return timer; | |
220 | } | |
221 | ||
222 | for (i = 0; i < TIMERS_PER_GROUP; i++) { | |
223 | /* one timer: Reverse allocation */ | |
224 | num = TIMERS_PER_GROUP - 1 - i; | |
225 | spin_lock_irqsave(&priv->lock, flags); | |
226 | if (priv->idle & (1 << i)) { | |
227 | /* set timer busy */ | |
228 | priv->idle &= ~(1 << i); | |
229 | /* set ticks & stop timer */ | |
230 | out_be32(&priv->regs[num].gtbcr, | |
231 | ticks | TIMER_STOP); | |
232 | out_be32(&priv->regs[num].gtccr, 0); | |
233 | priv->timer[num].cascade_handle = NULL; | |
234 | spin_unlock_irqrestore(&priv->lock, flags); | |
235 | return &priv->timer[num]; | |
236 | } | |
237 | spin_unlock_irqrestore(&priv->lock, flags); | |
238 | } | |
239 | } | |
240 | ||
241 | return NULL; | |
242 | } | |
243 | ||
244 | /** | |
245 | * mpic_start_timer - start hardware timer | |
246 | * @handle: the timer to be started. | |
247 | * | |
248 | * It will do ->fn(->dev) callback from the hardware interrupt at | |
11ed8c55 | 249 | * the 'time64_t' point in the future. |
36ca09be D |
250 | */ |
251 | void mpic_start_timer(struct mpic_timer *handle) | |
252 | { | |
253 | struct timer_group_priv *priv = container_of(handle, | |
254 | struct timer_group_priv, timer[handle->num]); | |
255 | ||
256 | clrbits32(&priv->regs[handle->num].gtbcr, TIMER_STOP); | |
257 | } | |
258 | EXPORT_SYMBOL(mpic_start_timer); | |
259 | ||
260 | /** | |
261 | * mpic_stop_timer - stop hardware timer | |
262 | * @handle: the timer to be stoped | |
263 | * | |
264 | * The timer periodically generates an interrupt. Unless user stops the timer. | |
265 | */ | |
266 | void mpic_stop_timer(struct mpic_timer *handle) | |
267 | { | |
268 | struct timer_group_priv *priv = container_of(handle, | |
269 | struct timer_group_priv, timer[handle->num]); | |
270 | struct cascade_priv *casc_priv; | |
271 | ||
272 | setbits32(&priv->regs[handle->num].gtbcr, TIMER_STOP); | |
273 | ||
274 | casc_priv = priv->timer[handle->num].cascade_handle; | |
275 | if (casc_priv) { | |
276 | out_be32(&priv->regs[handle->num].gtccr, 0); | |
277 | out_be32(&priv->regs[handle->num - 1].gtccr, 0); | |
278 | } else { | |
279 | out_be32(&priv->regs[handle->num].gtccr, 0); | |
280 | } | |
281 | } | |
282 | EXPORT_SYMBOL(mpic_stop_timer); | |
283 | ||
284 | /** | |
285 | * mpic_get_remain_time - get timer time | |
286 | * @handle: the timer to be selected. | |
287 | * @time: time for timer | |
288 | * | |
289 | * Query timer remaining time. | |
290 | */ | |
11ed8c55 | 291 | void mpic_get_remain_time(struct mpic_timer *handle, time64_t *time) |
36ca09be D |
292 | { |
293 | struct timer_group_priv *priv = container_of(handle, | |
294 | struct timer_group_priv, timer[handle->num]); | |
295 | struct cascade_priv *casc_priv; | |
296 | ||
297 | u64 ticks; | |
298 | u32 tmp_ticks; | |
299 | ||
300 | casc_priv = priv->timer[handle->num].cascade_handle; | |
301 | if (casc_priv) { | |
302 | tmp_ticks = in_be32(&priv->regs[handle->num].gtccr); | |
0fd79588 | 303 | tmp_ticks &= ~GTCCR_TOG; |
36ca09be D |
304 | ticks = ((u64)tmp_ticks & UINT_MAX) * (u64)MAX_TICKS_CASCADE; |
305 | tmp_ticks = in_be32(&priv->regs[handle->num - 1].gtccr); | |
306 | ticks += tmp_ticks; | |
307 | } else { | |
308 | ticks = in_be32(&priv->regs[handle->num].gtccr); | |
0fd79588 | 309 | ticks &= ~GTCCR_TOG; |
36ca09be D |
310 | } |
311 | ||
312 | convert_ticks_to_time(priv, ticks, time); | |
313 | } | |
314 | EXPORT_SYMBOL(mpic_get_remain_time); | |
315 | ||
316 | /** | |
317 | * mpic_free_timer - free hardware timer | |
318 | * @handle: the timer to be removed. | |
319 | * | |
320 | * Free the timer. | |
321 | * | |
322 | * Note: can not be used in interrupt context. | |
323 | */ | |
324 | void mpic_free_timer(struct mpic_timer *handle) | |
325 | { | |
326 | struct timer_group_priv *priv = container_of(handle, | |
327 | struct timer_group_priv, timer[handle->num]); | |
328 | ||
329 | struct cascade_priv *casc_priv; | |
330 | unsigned long flags; | |
331 | ||
332 | mpic_stop_timer(handle); | |
333 | ||
334 | casc_priv = priv->timer[handle->num].cascade_handle; | |
335 | ||
336 | free_irq(priv->timer[handle->num].irq, priv->timer[handle->num].dev); | |
337 | ||
338 | spin_lock_irqsave(&priv->lock, flags); | |
339 | if (casc_priv) { | |
340 | u32 tcr; | |
341 | tcr = casc_priv->tcr_value | (casc_priv->tcr_value << | |
342 | MPIC_TIMER_TCR_ROVR_OFFSET); | |
343 | clrbits32(priv->group_tcr, tcr); | |
344 | priv->idle |= casc_priv->cascade_map; | |
345 | priv->timer[handle->num].cascade_handle = NULL; | |
346 | } else { | |
347 | priv->idle |= TIMER_OFFSET(handle->num); | |
348 | } | |
349 | spin_unlock_irqrestore(&priv->lock, flags); | |
350 | } | |
351 | EXPORT_SYMBOL(mpic_free_timer); | |
352 | ||
353 | /** | |
354 | * mpic_request_timer - get a hardware timer | |
355 | * @fn: interrupt handler function | |
356 | * @dev: callback function of the data | |
357 | * @time: time for timer | |
358 | * | |
359 | * This executes the "request_irq", returning NULL | |
360 | * else "handle" on success. | |
361 | */ | |
362 | struct mpic_timer *mpic_request_timer(irq_handler_t fn, void *dev, | |
11ed8c55 | 363 | time64_t time) |
36ca09be D |
364 | { |
365 | struct mpic_timer *allocated_timer; | |
366 | int ret; | |
367 | ||
368 | if (list_empty(&timer_group_list)) | |
369 | return NULL; | |
370 | ||
11ed8c55 | 371 | if (time < 0) |
36ca09be D |
372 | return NULL; |
373 | ||
374 | allocated_timer = get_timer(time); | |
375 | if (!allocated_timer) | |
376 | return NULL; | |
377 | ||
378 | ret = request_irq(allocated_timer->irq, fn, | |
379 | IRQF_TRIGGER_LOW, "global-timer", dev); | |
380 | if (ret) { | |
381 | mpic_free_timer(allocated_timer); | |
382 | return NULL; | |
383 | } | |
384 | ||
385 | allocated_timer->dev = dev; | |
386 | ||
387 | return allocated_timer; | |
388 | } | |
389 | EXPORT_SYMBOL(mpic_request_timer); | |
390 | ||
391 | static int timer_group_get_freq(struct device_node *np, | |
392 | struct timer_group_priv *priv) | |
393 | { | |
394 | u32 div; | |
395 | ||
396 | if (priv->flags & FSL_GLOBAL_TIMER) { | |
397 | struct device_node *dn; | |
398 | ||
399 | dn = of_find_compatible_node(NULL, NULL, "fsl,mpic"); | |
400 | if (dn) { | |
401 | of_property_read_u32(dn, "clock-frequency", | |
402 | &priv->timerfreq); | |
403 | of_node_put(dn); | |
404 | } | |
405 | } | |
406 | ||
407 | if (priv->timerfreq <= 0) | |
408 | return -EINVAL; | |
409 | ||
410 | if (priv->flags & FSL_GLOBAL_TIMER) { | |
411 | div = (1 << (MPIC_TIMER_TCR_CLKDIV >> 8)) * 8; | |
412 | priv->timerfreq /= div; | |
413 | } | |
414 | ||
415 | return 0; | |
416 | } | |
417 | ||
418 | static int timer_group_get_irq(struct device_node *np, | |
419 | struct timer_group_priv *priv) | |
420 | { | |
421 | const u32 all_timer[] = { 0, TIMERS_PER_GROUP }; | |
422 | const u32 *p; | |
423 | u32 offset; | |
424 | u32 count; | |
425 | ||
426 | unsigned int i; | |
427 | unsigned int j; | |
428 | unsigned int irq_index = 0; | |
429 | unsigned int irq; | |
430 | int len; | |
431 | ||
432 | p = of_get_property(np, "fsl,available-ranges", &len); | |
433 | if (p && len % (2 * sizeof(u32)) != 0) { | |
b7c670d6 | 434 | pr_err("%pOF: malformed available-ranges property.\n", np); |
36ca09be D |
435 | return -EINVAL; |
436 | } | |
437 | ||
438 | if (!p) { | |
439 | p = all_timer; | |
440 | len = sizeof(all_timer); | |
441 | } | |
442 | ||
443 | len /= 2 * sizeof(u32); | |
444 | ||
445 | for (i = 0; i < len; i++) { | |
446 | offset = p[i * 2]; | |
447 | count = p[i * 2 + 1]; | |
448 | for (j = 0; j < count; j++) { | |
449 | irq = irq_of_parse_and_map(np, irq_index); | |
450 | if (!irq) { | |
b7c670d6 | 451 | pr_err("%pOF: irq parse and map failed.\n", np); |
36ca09be D |
452 | return -EINVAL; |
453 | } | |
454 | ||
455 | /* Set timer idle */ | |
456 | priv->idle |= TIMER_OFFSET((offset + j)); | |
457 | priv->timer[offset + j].irq = irq; | |
458 | priv->timer[offset + j].num = offset + j; | |
459 | irq_index++; | |
460 | } | |
461 | } | |
462 | ||
463 | return 0; | |
464 | } | |
465 | ||
466 | static void timer_group_init(struct device_node *np) | |
467 | { | |
468 | struct timer_group_priv *priv; | |
469 | unsigned int i = 0; | |
470 | int ret; | |
471 | ||
472 | priv = kzalloc(sizeof(struct timer_group_priv), GFP_KERNEL); | |
473 | if (!priv) { | |
b7c670d6 | 474 | pr_err("%pOF: cannot allocate memory for group.\n", np); |
36ca09be D |
475 | return; |
476 | } | |
477 | ||
478 | if (of_device_is_compatible(np, "fsl,mpic-global-timer")) | |
479 | priv->flags |= FSL_GLOBAL_TIMER; | |
480 | ||
481 | priv->regs = of_iomap(np, i++); | |
482 | if (!priv->regs) { | |
b7c670d6 | 483 | pr_err("%pOF: cannot ioremap timer register address.\n", np); |
36ca09be D |
484 | goto out; |
485 | } | |
486 | ||
487 | if (priv->flags & FSL_GLOBAL_TIMER) { | |
488 | priv->group_tcr = of_iomap(np, i++); | |
489 | if (!priv->group_tcr) { | |
b7c670d6 | 490 | pr_err("%pOF: cannot ioremap tcr address.\n", np); |
36ca09be D |
491 | goto out; |
492 | } | |
493 | } | |
494 | ||
495 | ret = timer_group_get_freq(np, priv); | |
496 | if (ret < 0) { | |
b7c670d6 | 497 | pr_err("%pOF: cannot get timer frequency.\n", np); |
36ca09be D |
498 | goto out; |
499 | } | |
500 | ||
501 | ret = timer_group_get_irq(np, priv); | |
502 | if (ret < 0) { | |
b7c670d6 | 503 | pr_err("%pOF: cannot get timer irqs.\n", np); |
36ca09be D |
504 | goto out; |
505 | } | |
506 | ||
507 | spin_lock_init(&priv->lock); | |
508 | ||
509 | /* Init FSL timer hardware */ | |
510 | if (priv->flags & FSL_GLOBAL_TIMER) | |
511 | setbits32(priv->group_tcr, MPIC_TIMER_TCR_CLKDIV); | |
512 | ||
513 | list_add_tail(&priv->node, &timer_group_list); | |
514 | ||
515 | return; | |
516 | ||
517 | out: | |
518 | if (priv->regs) | |
519 | iounmap(priv->regs); | |
520 | ||
521 | if (priv->group_tcr) | |
522 | iounmap(priv->group_tcr); | |
523 | ||
524 | kfree(priv); | |
525 | } | |
526 | ||
527 | static void mpic_timer_resume(void) | |
528 | { | |
529 | struct timer_group_priv *priv; | |
530 | ||
531 | list_for_each_entry(priv, &timer_group_list, node) { | |
532 | /* Init FSL timer hardware */ | |
533 | if (priv->flags & FSL_GLOBAL_TIMER) | |
534 | setbits32(priv->group_tcr, MPIC_TIMER_TCR_CLKDIV); | |
535 | } | |
536 | } | |
537 | ||
538 | static const struct of_device_id mpic_timer_ids[] = { | |
539 | { .compatible = "fsl,mpic-global-timer", }, | |
540 | {}, | |
541 | }; | |
542 | ||
543 | static struct syscore_ops mpic_timer_syscore_ops = { | |
544 | .resume = mpic_timer_resume, | |
545 | }; | |
546 | ||
547 | static int __init mpic_timer_init(void) | |
548 | { | |
549 | struct device_node *np = NULL; | |
550 | ||
551 | for_each_matching_node(np, mpic_timer_ids) | |
552 | timer_group_init(np); | |
553 | ||
554 | register_syscore_ops(&mpic_timer_syscore_ops); | |
555 | ||
556 | if (list_empty(&timer_group_list)) | |
557 | return -ENODEV; | |
558 | ||
559 | return 0; | |
560 | } | |
561 | subsys_initcall(mpic_timer_init); |