xref: /linux/drivers/clocksource/timer-ti-dm.c (revision 22d55f02b8922a097cd4be1e2f131dfa7ef65901)
1 /*
2  * linux/arch/arm/plat-omap/dmtimer.c
3  *
4  * OMAP Dual-Mode Timers
5  *
6  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
7  * Tarun Kanti DebBarma <tarun.kanti@ti.com>
8  * Thara Gopinath <thara@ti.com>
9  *
10  * dmtimer adaptation to platform_driver.
11  *
12  * Copyright (C) 2005 Nokia Corporation
13  * OMAP2 support by Juha Yrjola
14  * API improvements and OMAP2 clock framework support by Timo Teras
15  *
16  * Copyright (C) 2009 Texas Instruments
17  * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
18  *
19  * This program is free software; you can redistribute it and/or modify it
20  * under the terms of the GNU General Public License as published by the
21  * Free Software Foundation; either version 2 of the License, or (at your
22  * option) any later version.
23  *
24  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
27  * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29  * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  *
33  * You should have received a copy of the  GNU General Public License along
34  * with this program; if not, write  to the Free Software Foundation, Inc.,
35  * 675 Mass Ave, Cambridge, MA 02139, USA.
36  */
37 
38 #include <linux/clk.h>
39 #include <linux/clk-provider.h>
40 #include <linux/module.h>
41 #include <linux/io.h>
42 #include <linux/device.h>
43 #include <linux/err.h>
44 #include <linux/pm_runtime.h>
45 #include <linux/of.h>
46 #include <linux/of_device.h>
47 #include <linux/platform_device.h>
48 #include <linux/platform_data/dmtimer-omap.h>
49 
50 #include <clocksource/timer-ti-dm.h>
51 
52 static u32 omap_reserved_systimers;
53 static LIST_HEAD(omap_timer_list);
54 static DEFINE_SPINLOCK(dm_timer_lock);
55 
56 enum {
57 	REQUEST_ANY = 0,
58 	REQUEST_BY_ID,
59 	REQUEST_BY_CAP,
60 	REQUEST_BY_NODE,
61 };
62 
63 /**
64  * omap_dm_timer_read_reg - read timer registers in posted and non-posted mode
65  * @timer:      timer pointer over which read operation to perform
66  * @reg:        lowest byte holds the register offset
67  *
68  * The posted mode bit is encoded in reg. Note that in posted mode write
69  * pending bit must be checked. Otherwise a read of a non completed write
70  * will produce an error.
71  */
72 static inline u32 omap_dm_timer_read_reg(struct omap_dm_timer *timer, u32 reg)
73 {
74 	WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
75 	return __omap_dm_timer_read(timer, reg, timer->posted);
76 }
77 
78 /**
79  * omap_dm_timer_write_reg - write timer registers in posted and non-posted mode
80  * @timer:      timer pointer over which write operation is to perform
81  * @reg:        lowest byte holds the register offset
82  * @value:      data to write into the register
83  *
84  * The posted mode bit is encoded in reg. Note that in posted mode the write
85  * pending bit must be checked. Otherwise a write on a register which has a
86  * pending write will be lost.
87  */
88 static void omap_dm_timer_write_reg(struct omap_dm_timer *timer, u32 reg,
89 						u32 value)
90 {
91 	WARN_ON((reg & 0xff) < _OMAP_TIMER_WAKEUP_EN_OFFSET);
92 	__omap_dm_timer_write(timer, reg, value, timer->posted);
93 }
94 
95 static void omap_timer_restore_context(struct omap_dm_timer *timer)
96 {
97 	omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG,
98 				timer->context.twer);
99 	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG,
100 				timer->context.tcrr);
101 	omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG,
102 				timer->context.tldr);
103 	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG,
104 				timer->context.tmar);
105 	omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG,
106 				timer->context.tsicr);
107 	writel_relaxed(timer->context.tier, timer->irq_ena);
108 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG,
109 				timer->context.tclr);
110 }
111 
112 static int omap_dm_timer_reset(struct omap_dm_timer *timer)
113 {
114 	u32 l, timeout = 100000;
115 
116 	if (timer->revision != 1)
117 		return -EINVAL;
118 
119 	omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
120 
121 	do {
122 		l = __omap_dm_timer_read(timer,
123 					 OMAP_TIMER_V1_SYS_STAT_OFFSET, 0);
124 	} while (!l && timeout--);
125 
126 	if (!timeout) {
127 		dev_err(&timer->pdev->dev, "Timer failed to reset\n");
128 		return -ETIMEDOUT;
129 	}
130 
131 	/* Configure timer for smart-idle mode */
132 	l = __omap_dm_timer_read(timer, OMAP_TIMER_OCP_CFG_OFFSET, 0);
133 	l |= 0x2 << 0x3;
134 	__omap_dm_timer_write(timer, OMAP_TIMER_OCP_CFG_OFFSET, l, 0);
135 
136 	timer->posted = 0;
137 
138 	return 0;
139 }
140 
141 static int omap_dm_timer_of_set_source(struct omap_dm_timer *timer)
142 {
143 	int ret;
144 	struct clk *parent;
145 
146 	/*
147 	 * FIXME: OMAP1 devices do not use the clock framework for dmtimers so
148 	 * do not call clk_get() for these devices.
149 	 */
150 	if (!timer->fclk)
151 		return -ENODEV;
152 
153 	parent = clk_get(&timer->pdev->dev, NULL);
154 	if (IS_ERR(parent))
155 		return -ENODEV;
156 
157 	/* Bail out if both clocks point to fck */
158 	if (clk_is_match(parent, timer->fclk))
159 		return 0;
160 
161 	ret = clk_set_parent(timer->fclk, parent);
162 	if (ret < 0)
163 		pr_err("%s: failed to set parent\n", __func__);
164 
165 	clk_put(parent);
166 
167 	return ret;
168 }
169 
170 static int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
171 {
172 	int ret;
173 	const char *parent_name;
174 	struct clk *parent;
175 	struct dmtimer_platform_data *pdata;
176 
177 	if (unlikely(!timer) || IS_ERR(timer->fclk))
178 		return -EINVAL;
179 
180 	switch (source) {
181 	case OMAP_TIMER_SRC_SYS_CLK:
182 		parent_name = "timer_sys_ck";
183 		break;
184 	case OMAP_TIMER_SRC_32_KHZ:
185 		parent_name = "timer_32k_ck";
186 		break;
187 	case OMAP_TIMER_SRC_EXT_CLK:
188 		parent_name = "timer_ext_ck";
189 		break;
190 	default:
191 		return -EINVAL;
192 	}
193 
194 	pdata = timer->pdev->dev.platform_data;
195 
196 	/*
197 	 * FIXME: Used for OMAP1 devices only because they do not currently
198 	 * use the clock framework to set the parent clock. To be removed
199 	 * once OMAP1 migrated to using clock framework for dmtimers
200 	 */
201 	if (pdata && pdata->set_timer_src)
202 		return pdata->set_timer_src(timer->pdev, source);
203 
204 #if defined(CONFIG_COMMON_CLK)
205 	/* Check if the clock has configurable parents */
206 	if (clk_hw_get_num_parents(__clk_get_hw(timer->fclk)) < 2)
207 		return 0;
208 #endif
209 
210 	parent = clk_get(&timer->pdev->dev, parent_name);
211 	if (IS_ERR(parent)) {
212 		pr_err("%s: %s not found\n", __func__, parent_name);
213 		return -EINVAL;
214 	}
215 
216 	ret = clk_set_parent(timer->fclk, parent);
217 	if (ret < 0)
218 		pr_err("%s: failed to set %s as parent\n", __func__,
219 			parent_name);
220 
221 	clk_put(parent);
222 
223 	return ret;
224 }
225 
226 static void omap_dm_timer_enable(struct omap_dm_timer *timer)
227 {
228 	int c;
229 
230 	pm_runtime_get_sync(&timer->pdev->dev);
231 
232 	if (!(timer->capability & OMAP_TIMER_ALWON)) {
233 		if (timer->get_context_loss_count) {
234 			c = timer->get_context_loss_count(&timer->pdev->dev);
235 			if (c != timer->ctx_loss_count) {
236 				omap_timer_restore_context(timer);
237 				timer->ctx_loss_count = c;
238 			}
239 		} else {
240 			omap_timer_restore_context(timer);
241 		}
242 	}
243 }
244 
245 static void omap_dm_timer_disable(struct omap_dm_timer *timer)
246 {
247 	pm_runtime_put_sync(&timer->pdev->dev);
248 }
249 
250 static int omap_dm_timer_prepare(struct omap_dm_timer *timer)
251 {
252 	int rc;
253 
254 	/*
255 	 * FIXME: OMAP1 devices do not use the clock framework for dmtimers so
256 	 * do not call clk_get() for these devices.
257 	 */
258 	if (!(timer->capability & OMAP_TIMER_NEEDS_RESET)) {
259 		timer->fclk = clk_get(&timer->pdev->dev, "fck");
260 		if (WARN_ON_ONCE(IS_ERR(timer->fclk))) {
261 			dev_err(&timer->pdev->dev, ": No fclk handle.\n");
262 			return -EINVAL;
263 		}
264 	}
265 
266 	omap_dm_timer_enable(timer);
267 
268 	if (timer->capability & OMAP_TIMER_NEEDS_RESET) {
269 		rc = omap_dm_timer_reset(timer);
270 		if (rc) {
271 			omap_dm_timer_disable(timer);
272 			return rc;
273 		}
274 	}
275 
276 	__omap_dm_timer_enable_posted(timer);
277 	omap_dm_timer_disable(timer);
278 
279 	rc = omap_dm_timer_of_set_source(timer);
280 	if (rc == -ENODEV)
281 		return omap_dm_timer_set_source(timer, OMAP_TIMER_SRC_32_KHZ);
282 
283 	return rc;
284 }
285 
286 static inline u32 omap_dm_timer_reserved_systimer(int id)
287 {
288 	return (omap_reserved_systimers & (1 << (id - 1))) ? 1 : 0;
289 }
290 
291 int omap_dm_timer_reserve_systimer(int id)
292 {
293 	if (omap_dm_timer_reserved_systimer(id))
294 		return -ENODEV;
295 
296 	omap_reserved_systimers |= (1 << (id - 1));
297 
298 	return 0;
299 }
300 
301 static struct omap_dm_timer *_omap_dm_timer_request(int req_type, void *data)
302 {
303 	struct omap_dm_timer *timer = NULL, *t;
304 	struct device_node *np = NULL;
305 	unsigned long flags;
306 	u32 cap = 0;
307 	int id = 0;
308 
309 	switch (req_type) {
310 	case REQUEST_BY_ID:
311 		id = *(int *)data;
312 		break;
313 	case REQUEST_BY_CAP:
314 		cap = *(u32 *)data;
315 		break;
316 	case REQUEST_BY_NODE:
317 		np = (struct device_node *)data;
318 		break;
319 	default:
320 		/* REQUEST_ANY */
321 		break;
322 	}
323 
324 	spin_lock_irqsave(&dm_timer_lock, flags);
325 	list_for_each_entry(t, &omap_timer_list, node) {
326 		if (t->reserved)
327 			continue;
328 
329 		switch (req_type) {
330 		case REQUEST_BY_ID:
331 			if (id == t->pdev->id) {
332 				timer = t;
333 				timer->reserved = 1;
334 				goto found;
335 			}
336 			break;
337 		case REQUEST_BY_CAP:
338 			if (cap == (t->capability & cap)) {
339 				/*
340 				 * If timer is not NULL, we have already found
341 				 * one timer. But it was not an exact match
342 				 * because it had more capabilities than what
343 				 * was required. Therefore, unreserve the last
344 				 * timer found and see if this one is a better
345 				 * match.
346 				 */
347 				if (timer)
348 					timer->reserved = 0;
349 				timer = t;
350 				timer->reserved = 1;
351 
352 				/* Exit loop early if we find an exact match */
353 				if (t->capability == cap)
354 					goto found;
355 			}
356 			break;
357 		case REQUEST_BY_NODE:
358 			if (np == t->pdev->dev.of_node) {
359 				timer = t;
360 				timer->reserved = 1;
361 				goto found;
362 			}
363 			break;
364 		default:
365 			/* REQUEST_ANY */
366 			timer = t;
367 			timer->reserved = 1;
368 			goto found;
369 		}
370 	}
371 found:
372 	spin_unlock_irqrestore(&dm_timer_lock, flags);
373 
374 	if (timer && omap_dm_timer_prepare(timer)) {
375 		timer->reserved = 0;
376 		timer = NULL;
377 	}
378 
379 	if (!timer)
380 		pr_debug("%s: timer request failed!\n", __func__);
381 
382 	return timer;
383 }
384 
385 static struct omap_dm_timer *omap_dm_timer_request(void)
386 {
387 	return _omap_dm_timer_request(REQUEST_ANY, NULL);
388 }
389 
390 static struct omap_dm_timer *omap_dm_timer_request_specific(int id)
391 {
392 	/* Requesting timer by ID is not supported when device tree is used */
393 	if (of_have_populated_dt()) {
394 		pr_warn("%s: Please use omap_dm_timer_request_by_node()\n",
395 			__func__);
396 		return NULL;
397 	}
398 
399 	return _omap_dm_timer_request(REQUEST_BY_ID, &id);
400 }
401 
402 /**
403  * omap_dm_timer_request_by_cap - Request a timer by capability
404  * @cap:	Bit mask of capabilities to match
405  *
406  * Find a timer based upon capabilities bit mask. Callers of this function
407  * should use the definitions found in the plat/dmtimer.h file under the
408  * comment "timer capabilities used in hwmod database". Returns pointer to
409  * timer handle on success and a NULL pointer on failure.
410  */
411 struct omap_dm_timer *omap_dm_timer_request_by_cap(u32 cap)
412 {
413 	return _omap_dm_timer_request(REQUEST_BY_CAP, &cap);
414 }
415 
416 /**
417  * omap_dm_timer_request_by_node - Request a timer by device-tree node
418  * @np:		Pointer to device-tree timer node
419  *
420  * Request a timer based upon a device node pointer. Returns pointer to
421  * timer handle on success and a NULL pointer on failure.
422  */
423 static struct omap_dm_timer *omap_dm_timer_request_by_node(struct device_node *np)
424 {
425 	if (!np)
426 		return NULL;
427 
428 	return _omap_dm_timer_request(REQUEST_BY_NODE, np);
429 }
430 
431 static int omap_dm_timer_free(struct omap_dm_timer *timer)
432 {
433 	if (unlikely(!timer))
434 		return -EINVAL;
435 
436 	clk_put(timer->fclk);
437 
438 	WARN_ON(!timer->reserved);
439 	timer->reserved = 0;
440 	return 0;
441 }
442 
443 int omap_dm_timer_get_irq(struct omap_dm_timer *timer)
444 {
445 	if (timer)
446 		return timer->irq;
447 	return -EINVAL;
448 }
449 
450 #if defined(CONFIG_ARCH_OMAP1)
451 #include <mach/hardware.h>
452 
453 static struct clk *omap_dm_timer_get_fclk(struct omap_dm_timer *timer)
454 {
455 	return NULL;
456 }
457 
458 /**
459  * omap_dm_timer_modify_idlect_mask - Check if any running timers use ARMXOR
460  * @inputmask: current value of idlect mask
461  */
462 __u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
463 {
464 	int i = 0;
465 	struct omap_dm_timer *timer = NULL;
466 	unsigned long flags;
467 
468 	/* If ARMXOR cannot be idled this function call is unnecessary */
469 	if (!(inputmask & (1 << 1)))
470 		return inputmask;
471 
472 	/* If any active timer is using ARMXOR return modified mask */
473 	spin_lock_irqsave(&dm_timer_lock, flags);
474 	list_for_each_entry(timer, &omap_timer_list, node) {
475 		u32 l;
476 
477 		l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
478 		if (l & OMAP_TIMER_CTRL_ST) {
479 			if (((omap_readl(MOD_CONF_CTRL_1) >> (i * 2)) & 0x03) == 0)
480 				inputmask &= ~(1 << 1);
481 			else
482 				inputmask &= ~(1 << 2);
483 		}
484 		i++;
485 	}
486 	spin_unlock_irqrestore(&dm_timer_lock, flags);
487 
488 	return inputmask;
489 }
490 
491 #else
492 
493 static struct clk *omap_dm_timer_get_fclk(struct omap_dm_timer *timer)
494 {
495 	if (timer && !IS_ERR(timer->fclk))
496 		return timer->fclk;
497 	return NULL;
498 }
499 
500 __u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
501 {
502 	BUG();
503 
504 	return 0;
505 }
506 
507 #endif
508 
509 int omap_dm_timer_trigger(struct omap_dm_timer *timer)
510 {
511 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
512 		pr_err("%s: timer not available or enabled.\n", __func__);
513 		return -EINVAL;
514 	}
515 
516 	omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
517 	return 0;
518 }
519 
520 static int omap_dm_timer_start(struct omap_dm_timer *timer)
521 {
522 	u32 l;
523 
524 	if (unlikely(!timer))
525 		return -EINVAL;
526 
527 	omap_dm_timer_enable(timer);
528 
529 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
530 	if (!(l & OMAP_TIMER_CTRL_ST)) {
531 		l |= OMAP_TIMER_CTRL_ST;
532 		omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
533 	}
534 
535 	/* Save the context */
536 	timer->context.tclr = l;
537 	return 0;
538 }
539 
540 static int omap_dm_timer_stop(struct omap_dm_timer *timer)
541 {
542 	unsigned long rate = 0;
543 
544 	if (unlikely(!timer))
545 		return -EINVAL;
546 
547 	if (!(timer->capability & OMAP_TIMER_NEEDS_RESET))
548 		rate = clk_get_rate(timer->fclk);
549 
550 	__omap_dm_timer_stop(timer, timer->posted, rate);
551 
552 	/*
553 	 * Since the register values are computed and written within
554 	 * __omap_dm_timer_stop, we need to use read to retrieve the
555 	 * context.
556 	 */
557 	timer->context.tclr =
558 			omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
559 	omap_dm_timer_disable(timer);
560 	return 0;
561 }
562 
563 static int omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
564 				  unsigned int load)
565 {
566 	u32 l;
567 
568 	if (unlikely(!timer))
569 		return -EINVAL;
570 
571 	omap_dm_timer_enable(timer);
572 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
573 	if (autoreload)
574 		l |= OMAP_TIMER_CTRL_AR;
575 	else
576 		l &= ~OMAP_TIMER_CTRL_AR;
577 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
578 	omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG, load);
579 
580 	omap_dm_timer_write_reg(timer, OMAP_TIMER_TRIGGER_REG, 0);
581 	/* Save the context */
582 	timer->context.tclr = l;
583 	timer->context.tldr = load;
584 	omap_dm_timer_disable(timer);
585 	return 0;
586 }
587 
588 static int omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
589 				   unsigned int match)
590 {
591 	u32 l;
592 
593 	if (unlikely(!timer))
594 		return -EINVAL;
595 
596 	omap_dm_timer_enable(timer);
597 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
598 	if (enable)
599 		l |= OMAP_TIMER_CTRL_CE;
600 	else
601 		l &= ~OMAP_TIMER_CTRL_CE;
602 	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG, match);
603 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
604 
605 	/* Save the context */
606 	timer->context.tclr = l;
607 	timer->context.tmar = match;
608 	omap_dm_timer_disable(timer);
609 	return 0;
610 }
611 
612 static int omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
613 				 int toggle, int trigger)
614 {
615 	u32 l;
616 
617 	if (unlikely(!timer))
618 		return -EINVAL;
619 
620 	omap_dm_timer_enable(timer);
621 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
622 	l &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM |
623 	       OMAP_TIMER_CTRL_PT | (0x03 << 10));
624 	if (def_on)
625 		l |= OMAP_TIMER_CTRL_SCPWM;
626 	if (toggle)
627 		l |= OMAP_TIMER_CTRL_PT;
628 	l |= trigger << 10;
629 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
630 
631 	/* Save the context */
632 	timer->context.tclr = l;
633 	omap_dm_timer_disable(timer);
634 	return 0;
635 }
636 
637 static int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer,
638 					int prescaler)
639 {
640 	u32 l;
641 
642 	if (unlikely(!timer) || prescaler < -1 || prescaler > 7)
643 		return -EINVAL;
644 
645 	omap_dm_timer_enable(timer);
646 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
647 	l &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2));
648 	if (prescaler >= 0) {
649 		l |= OMAP_TIMER_CTRL_PRE;
650 		l |= prescaler << 2;
651 	}
652 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
653 
654 	/* Save the context */
655 	timer->context.tclr = l;
656 	omap_dm_timer_disable(timer);
657 	return 0;
658 }
659 
660 static int omap_dm_timer_set_int_enable(struct omap_dm_timer *timer,
661 					unsigned int value)
662 {
663 	if (unlikely(!timer))
664 		return -EINVAL;
665 
666 	omap_dm_timer_enable(timer);
667 	__omap_dm_timer_int_enable(timer, value);
668 
669 	/* Save the context */
670 	timer->context.tier = value;
671 	timer->context.twer = value;
672 	omap_dm_timer_disable(timer);
673 	return 0;
674 }
675 
676 /**
677  * omap_dm_timer_set_int_disable - disable timer interrupts
678  * @timer:	pointer to timer handle
679  * @mask:	bit mask of interrupts to be disabled
680  *
681  * Disables the specified timer interrupts for a timer.
682  */
683 static int omap_dm_timer_set_int_disable(struct omap_dm_timer *timer, u32 mask)
684 {
685 	u32 l = mask;
686 
687 	if (unlikely(!timer))
688 		return -EINVAL;
689 
690 	omap_dm_timer_enable(timer);
691 
692 	if (timer->revision == 1)
693 		l = readl_relaxed(timer->irq_ena) & ~mask;
694 
695 	writel_relaxed(l, timer->irq_dis);
696 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_WAKEUP_EN_REG) & ~mask;
697 	omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG, l);
698 
699 	/* Save the context */
700 	timer->context.tier &= ~mask;
701 	timer->context.twer &= ~mask;
702 	omap_dm_timer_disable(timer);
703 	return 0;
704 }
705 
706 static unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer)
707 {
708 	unsigned int l;
709 
710 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
711 		pr_err("%s: timer not available or enabled.\n", __func__);
712 		return 0;
713 	}
714 
715 	l = readl_relaxed(timer->irq_stat);
716 
717 	return l;
718 }
719 
720 static int omap_dm_timer_write_status(struct omap_dm_timer *timer, unsigned int value)
721 {
722 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev)))
723 		return -EINVAL;
724 
725 	__omap_dm_timer_write_status(timer, value);
726 
727 	return 0;
728 }
729 
730 static unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *timer)
731 {
732 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
733 		pr_err("%s: timer not iavailable or enabled.\n", __func__);
734 		return 0;
735 	}
736 
737 	return __omap_dm_timer_read_counter(timer, timer->posted);
738 }
739 
740 static int omap_dm_timer_write_counter(struct omap_dm_timer *timer, unsigned int value)
741 {
742 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
743 		pr_err("%s: timer not available or enabled.\n", __func__);
744 		return -EINVAL;
745 	}
746 
747 	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG, value);
748 
749 	/* Save the context */
750 	timer->context.tcrr = value;
751 	return 0;
752 }
753 
754 int omap_dm_timers_active(void)
755 {
756 	struct omap_dm_timer *timer;
757 
758 	list_for_each_entry(timer, &omap_timer_list, node) {
759 		if (!timer->reserved)
760 			continue;
761 
762 		if (omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG) &
763 		    OMAP_TIMER_CTRL_ST) {
764 			return 1;
765 		}
766 	}
767 	return 0;
768 }
769 
770 static const struct of_device_id omap_timer_match[];
771 
772 /**
773  * omap_dm_timer_probe - probe function called for every registered device
774  * @pdev:	pointer to current timer platform device
775  *
776  * Called by driver framework at the end of device registration for all
777  * timer devices.
778  */
779 static int omap_dm_timer_probe(struct platform_device *pdev)
780 {
781 	unsigned long flags;
782 	struct omap_dm_timer *timer;
783 	struct resource *mem, *irq;
784 	struct device *dev = &pdev->dev;
785 	const struct dmtimer_platform_data *pdata;
786 	int ret;
787 
788 	pdata = of_device_get_match_data(dev);
789 	if (!pdata)
790 		pdata = dev_get_platdata(dev);
791 	else
792 		dev->platform_data = (void *)pdata;
793 
794 	if (!pdata) {
795 		dev_err(dev, "%s: no platform data.\n", __func__);
796 		return -ENODEV;
797 	}
798 
799 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
800 	if (unlikely(!irq)) {
801 		dev_err(dev, "%s: no IRQ resource.\n", __func__);
802 		return -ENODEV;
803 	}
804 
805 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
806 	if (unlikely(!mem)) {
807 		dev_err(dev, "%s: no memory resource.\n", __func__);
808 		return -ENODEV;
809 	}
810 
811 	timer = devm_kzalloc(dev, sizeof(*timer), GFP_KERNEL);
812 	if (!timer)
813 		return  -ENOMEM;
814 
815 	timer->fclk = ERR_PTR(-ENODEV);
816 	timer->io_base = devm_ioremap_resource(dev, mem);
817 	if (IS_ERR(timer->io_base))
818 		return PTR_ERR(timer->io_base);
819 
820 	if (dev->of_node) {
821 		if (of_find_property(dev->of_node, "ti,timer-alwon", NULL))
822 			timer->capability |= OMAP_TIMER_ALWON;
823 		if (of_find_property(dev->of_node, "ti,timer-dsp", NULL))
824 			timer->capability |= OMAP_TIMER_HAS_DSP_IRQ;
825 		if (of_find_property(dev->of_node, "ti,timer-pwm", NULL))
826 			timer->capability |= OMAP_TIMER_HAS_PWM;
827 		if (of_find_property(dev->of_node, "ti,timer-secure", NULL))
828 			timer->capability |= OMAP_TIMER_SECURE;
829 	} else {
830 		timer->id = pdev->id;
831 		timer->capability = pdata->timer_capability;
832 		timer->reserved = omap_dm_timer_reserved_systimer(timer->id);
833 		timer->get_context_loss_count = pdata->get_context_loss_count;
834 	}
835 
836 	if (pdata)
837 		timer->errata = pdata->timer_errata;
838 
839 	timer->irq = irq->start;
840 	timer->pdev = pdev;
841 
842 	pm_runtime_enable(dev);
843 
844 	if (!timer->reserved) {
845 		ret = pm_runtime_get_sync(dev);
846 		if (ret < 0) {
847 			dev_err(dev, "%s: pm_runtime_get_sync failed!\n",
848 				__func__);
849 			goto err_get_sync;
850 		}
851 		__omap_dm_timer_init_regs(timer);
852 		pm_runtime_put(dev);
853 	}
854 
855 	/* add the timer element to the list */
856 	spin_lock_irqsave(&dm_timer_lock, flags);
857 	list_add_tail(&timer->node, &omap_timer_list);
858 	spin_unlock_irqrestore(&dm_timer_lock, flags);
859 
860 	dev_dbg(dev, "Device Probed.\n");
861 
862 	return 0;
863 
864 err_get_sync:
865 	pm_runtime_put_noidle(dev);
866 	pm_runtime_disable(dev);
867 	return ret;
868 }
869 
870 /**
871  * omap_dm_timer_remove - cleanup a registered timer device
872  * @pdev:	pointer to current timer platform device
873  *
874  * Called by driver framework whenever a timer device is unregistered.
875  * In addition to freeing platform resources it also deletes the timer
876  * entry from the local list.
877  */
878 static int omap_dm_timer_remove(struct platform_device *pdev)
879 {
880 	struct omap_dm_timer *timer;
881 	unsigned long flags;
882 	int ret = -EINVAL;
883 
884 	spin_lock_irqsave(&dm_timer_lock, flags);
885 	list_for_each_entry(timer, &omap_timer_list, node)
886 		if (!strcmp(dev_name(&timer->pdev->dev),
887 			    dev_name(&pdev->dev))) {
888 			list_del(&timer->node);
889 			ret = 0;
890 			break;
891 		}
892 	spin_unlock_irqrestore(&dm_timer_lock, flags);
893 
894 	pm_runtime_disable(&pdev->dev);
895 
896 	return ret;
897 }
898 
899 static const struct omap_dm_timer_ops dmtimer_ops = {
900 	.request_by_node = omap_dm_timer_request_by_node,
901 	.request_specific = omap_dm_timer_request_specific,
902 	.request = omap_dm_timer_request,
903 	.set_source = omap_dm_timer_set_source,
904 	.get_irq = omap_dm_timer_get_irq,
905 	.set_int_enable = omap_dm_timer_set_int_enable,
906 	.set_int_disable = omap_dm_timer_set_int_disable,
907 	.free = omap_dm_timer_free,
908 	.enable = omap_dm_timer_enable,
909 	.disable = omap_dm_timer_disable,
910 	.get_fclk = omap_dm_timer_get_fclk,
911 	.start = omap_dm_timer_start,
912 	.stop = omap_dm_timer_stop,
913 	.set_load = omap_dm_timer_set_load,
914 	.set_match = omap_dm_timer_set_match,
915 	.set_pwm = omap_dm_timer_set_pwm,
916 	.set_prescaler = omap_dm_timer_set_prescaler,
917 	.read_counter = omap_dm_timer_read_counter,
918 	.write_counter = omap_dm_timer_write_counter,
919 	.read_status = omap_dm_timer_read_status,
920 	.write_status = omap_dm_timer_write_status,
921 };
922 
923 static const struct dmtimer_platform_data omap3plus_pdata = {
924 	.timer_errata = OMAP_TIMER_ERRATA_I103_I767,
925 	.timer_ops = &dmtimer_ops,
926 };
927 
928 static const struct of_device_id omap_timer_match[] = {
929 	{
930 		.compatible = "ti,omap2420-timer",
931 	},
932 	{
933 		.compatible = "ti,omap3430-timer",
934 		.data = &omap3plus_pdata,
935 	},
936 	{
937 		.compatible = "ti,omap4430-timer",
938 		.data = &omap3plus_pdata,
939 	},
940 	{
941 		.compatible = "ti,omap5430-timer",
942 		.data = &omap3plus_pdata,
943 	},
944 	{
945 		.compatible = "ti,am335x-timer",
946 		.data = &omap3plus_pdata,
947 	},
948 	{
949 		.compatible = "ti,am335x-timer-1ms",
950 		.data = &omap3plus_pdata,
951 	},
952 	{
953 		.compatible = "ti,dm816-timer",
954 		.data = &omap3plus_pdata,
955 	},
956 	{},
957 };
958 MODULE_DEVICE_TABLE(of, omap_timer_match);
959 
960 static struct platform_driver omap_dm_timer_driver = {
961 	.probe  = omap_dm_timer_probe,
962 	.remove = omap_dm_timer_remove,
963 	.driver = {
964 		.name   = "omap_timer",
965 		.of_match_table = of_match_ptr(omap_timer_match),
966 	},
967 };
968 
969 module_platform_driver(omap_dm_timer_driver);
970 
971 MODULE_DESCRIPTION("OMAP Dual-Mode Timer Driver");
972 MODULE_LICENSE("GPL");
973 MODULE_AUTHOR("Texas Instruments Inc");
974