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 /* Optimized set_load which removes costly spin wait in timer_start */
589 static int omap_dm_timer_set_load_start(struct omap_dm_timer *timer,
590 					int autoreload, unsigned int load)
591 {
592 	u32 l;
593 
594 	if (unlikely(!timer))
595 		return -EINVAL;
596 
597 	omap_dm_timer_enable(timer);
598 
599 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
600 	if (autoreload) {
601 		l |= OMAP_TIMER_CTRL_AR;
602 		omap_dm_timer_write_reg(timer, OMAP_TIMER_LOAD_REG, load);
603 	} else {
604 		l &= ~OMAP_TIMER_CTRL_AR;
605 	}
606 	l |= OMAP_TIMER_CTRL_ST;
607 
608 	__omap_dm_timer_load_start(timer, l, load, timer->posted);
609 
610 	/* Save the context */
611 	timer->context.tclr = l;
612 	timer->context.tldr = load;
613 	timer->context.tcrr = load;
614 	return 0;
615 }
616 static int omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
617 				   unsigned int match)
618 {
619 	u32 l;
620 
621 	if (unlikely(!timer))
622 		return -EINVAL;
623 
624 	omap_dm_timer_enable(timer);
625 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
626 	if (enable)
627 		l |= OMAP_TIMER_CTRL_CE;
628 	else
629 		l &= ~OMAP_TIMER_CTRL_CE;
630 	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG, match);
631 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
632 
633 	/* Save the context */
634 	timer->context.tclr = l;
635 	timer->context.tmar = match;
636 	omap_dm_timer_disable(timer);
637 	return 0;
638 }
639 
640 static int omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
641 				 int toggle, int trigger)
642 {
643 	u32 l;
644 
645 	if (unlikely(!timer))
646 		return -EINVAL;
647 
648 	omap_dm_timer_enable(timer);
649 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
650 	l &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM |
651 	       OMAP_TIMER_CTRL_PT | (0x03 << 10));
652 	if (def_on)
653 		l |= OMAP_TIMER_CTRL_SCPWM;
654 	if (toggle)
655 		l |= OMAP_TIMER_CTRL_PT;
656 	l |= trigger << 10;
657 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
658 
659 	/* Save the context */
660 	timer->context.tclr = l;
661 	omap_dm_timer_disable(timer);
662 	return 0;
663 }
664 
665 static int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer,
666 					int prescaler)
667 {
668 	u32 l;
669 
670 	if (unlikely(!timer) || prescaler < -1 || prescaler > 7)
671 		return -EINVAL;
672 
673 	omap_dm_timer_enable(timer);
674 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
675 	l &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2));
676 	if (prescaler >= 0) {
677 		l |= OMAP_TIMER_CTRL_PRE;
678 		l |= prescaler << 2;
679 	}
680 	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
681 
682 	/* Save the context */
683 	timer->context.tclr = l;
684 	omap_dm_timer_disable(timer);
685 	return 0;
686 }
687 
688 static int omap_dm_timer_set_int_enable(struct omap_dm_timer *timer,
689 					unsigned int value)
690 {
691 	if (unlikely(!timer))
692 		return -EINVAL;
693 
694 	omap_dm_timer_enable(timer);
695 	__omap_dm_timer_int_enable(timer, value);
696 
697 	/* Save the context */
698 	timer->context.tier = value;
699 	timer->context.twer = value;
700 	omap_dm_timer_disable(timer);
701 	return 0;
702 }
703 
704 /**
705  * omap_dm_timer_set_int_disable - disable timer interrupts
706  * @timer:	pointer to timer handle
707  * @mask:	bit mask of interrupts to be disabled
708  *
709  * Disables the specified timer interrupts for a timer.
710  */
711 static int omap_dm_timer_set_int_disable(struct omap_dm_timer *timer, u32 mask)
712 {
713 	u32 l = mask;
714 
715 	if (unlikely(!timer))
716 		return -EINVAL;
717 
718 	omap_dm_timer_enable(timer);
719 
720 	if (timer->revision == 1)
721 		l = readl_relaxed(timer->irq_ena) & ~mask;
722 
723 	writel_relaxed(l, timer->irq_dis);
724 	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_WAKEUP_EN_REG) & ~mask;
725 	omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG, l);
726 
727 	/* Save the context */
728 	timer->context.tier &= ~mask;
729 	timer->context.twer &= ~mask;
730 	omap_dm_timer_disable(timer);
731 	return 0;
732 }
733 
734 static unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer)
735 {
736 	unsigned int l;
737 
738 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
739 		pr_err("%s: timer not available or enabled.\n", __func__);
740 		return 0;
741 	}
742 
743 	l = readl_relaxed(timer->irq_stat);
744 
745 	return l;
746 }
747 
748 static int omap_dm_timer_write_status(struct omap_dm_timer *timer, unsigned int value)
749 {
750 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev)))
751 		return -EINVAL;
752 
753 	__omap_dm_timer_write_status(timer, value);
754 
755 	return 0;
756 }
757 
758 static unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *timer)
759 {
760 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
761 		pr_err("%s: timer not iavailable or enabled.\n", __func__);
762 		return 0;
763 	}
764 
765 	return __omap_dm_timer_read_counter(timer, timer->posted);
766 }
767 
768 static int omap_dm_timer_write_counter(struct omap_dm_timer *timer, unsigned int value)
769 {
770 	if (unlikely(!timer || pm_runtime_suspended(&timer->pdev->dev))) {
771 		pr_err("%s: timer not available or enabled.\n", __func__);
772 		return -EINVAL;
773 	}
774 
775 	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG, value);
776 
777 	/* Save the context */
778 	timer->context.tcrr = value;
779 	return 0;
780 }
781 
782 int omap_dm_timers_active(void)
783 {
784 	struct omap_dm_timer *timer;
785 
786 	list_for_each_entry(timer, &omap_timer_list, node) {
787 		if (!timer->reserved)
788 			continue;
789 
790 		if (omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG) &
791 		    OMAP_TIMER_CTRL_ST) {
792 			return 1;
793 		}
794 	}
795 	return 0;
796 }
797 
798 static const struct of_device_id omap_timer_match[];
799 
800 /**
801  * omap_dm_timer_probe - probe function called for every registered device
802  * @pdev:	pointer to current timer platform device
803  *
804  * Called by driver framework at the end of device registration for all
805  * timer devices.
806  */
807 static int omap_dm_timer_probe(struct platform_device *pdev)
808 {
809 	unsigned long flags;
810 	struct omap_dm_timer *timer;
811 	struct resource *mem, *irq;
812 	struct device *dev = &pdev->dev;
813 	const struct dmtimer_platform_data *pdata;
814 	int ret;
815 
816 	pdata = of_device_get_match_data(dev);
817 	if (!pdata)
818 		pdata = dev_get_platdata(dev);
819 	else
820 		dev->platform_data = (void *)pdata;
821 
822 	if (!pdata) {
823 		dev_err(dev, "%s: no platform data.\n", __func__);
824 		return -ENODEV;
825 	}
826 
827 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
828 	if (unlikely(!irq)) {
829 		dev_err(dev, "%s: no IRQ resource.\n", __func__);
830 		return -ENODEV;
831 	}
832 
833 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
834 	if (unlikely(!mem)) {
835 		dev_err(dev, "%s: no memory resource.\n", __func__);
836 		return -ENODEV;
837 	}
838 
839 	timer = devm_kzalloc(dev, sizeof(*timer), GFP_KERNEL);
840 	if (!timer)
841 		return  -ENOMEM;
842 
843 	timer->fclk = ERR_PTR(-ENODEV);
844 	timer->io_base = devm_ioremap_resource(dev, mem);
845 	if (IS_ERR(timer->io_base))
846 		return PTR_ERR(timer->io_base);
847 
848 	if (dev->of_node) {
849 		if (of_find_property(dev->of_node, "ti,timer-alwon", NULL))
850 			timer->capability |= OMAP_TIMER_ALWON;
851 		if (of_find_property(dev->of_node, "ti,timer-dsp", NULL))
852 			timer->capability |= OMAP_TIMER_HAS_DSP_IRQ;
853 		if (of_find_property(dev->of_node, "ti,timer-pwm", NULL))
854 			timer->capability |= OMAP_TIMER_HAS_PWM;
855 		if (of_find_property(dev->of_node, "ti,timer-secure", NULL))
856 			timer->capability |= OMAP_TIMER_SECURE;
857 	} else {
858 		timer->id = pdev->id;
859 		timer->capability = pdata->timer_capability;
860 		timer->reserved = omap_dm_timer_reserved_systimer(timer->id);
861 		timer->get_context_loss_count = pdata->get_context_loss_count;
862 	}
863 
864 	if (pdata)
865 		timer->errata = pdata->timer_errata;
866 
867 	timer->irq = irq->start;
868 	timer->pdev = pdev;
869 
870 	pm_runtime_enable(dev);
871 
872 	if (!timer->reserved) {
873 		ret = pm_runtime_get_sync(dev);
874 		if (ret < 0) {
875 			dev_err(dev, "%s: pm_runtime_get_sync failed!\n",
876 				__func__);
877 			goto err_get_sync;
878 		}
879 		__omap_dm_timer_init_regs(timer);
880 		pm_runtime_put(dev);
881 	}
882 
883 	/* add the timer element to the list */
884 	spin_lock_irqsave(&dm_timer_lock, flags);
885 	list_add_tail(&timer->node, &omap_timer_list);
886 	spin_unlock_irqrestore(&dm_timer_lock, flags);
887 
888 	dev_dbg(dev, "Device Probed.\n");
889 
890 	return 0;
891 
892 err_get_sync:
893 	pm_runtime_put_noidle(dev);
894 	pm_runtime_disable(dev);
895 	return ret;
896 }
897 
898 /**
899  * omap_dm_timer_remove - cleanup a registered timer device
900  * @pdev:	pointer to current timer platform device
901  *
902  * Called by driver framework whenever a timer device is unregistered.
903  * In addition to freeing platform resources it also deletes the timer
904  * entry from the local list.
905  */
906 static int omap_dm_timer_remove(struct platform_device *pdev)
907 {
908 	struct omap_dm_timer *timer;
909 	unsigned long flags;
910 	int ret = -EINVAL;
911 
912 	spin_lock_irqsave(&dm_timer_lock, flags);
913 	list_for_each_entry(timer, &omap_timer_list, node)
914 		if (!strcmp(dev_name(&timer->pdev->dev),
915 			    dev_name(&pdev->dev))) {
916 			list_del(&timer->node);
917 			ret = 0;
918 			break;
919 		}
920 	spin_unlock_irqrestore(&dm_timer_lock, flags);
921 
922 	pm_runtime_disable(&pdev->dev);
923 
924 	return ret;
925 }
926 
927 const static struct omap_dm_timer_ops dmtimer_ops = {
928 	.request_by_node = omap_dm_timer_request_by_node,
929 	.request_specific = omap_dm_timer_request_specific,
930 	.request = omap_dm_timer_request,
931 	.set_source = omap_dm_timer_set_source,
932 	.get_irq = omap_dm_timer_get_irq,
933 	.set_int_enable = omap_dm_timer_set_int_enable,
934 	.set_int_disable = omap_dm_timer_set_int_disable,
935 	.free = omap_dm_timer_free,
936 	.enable = omap_dm_timer_enable,
937 	.disable = omap_dm_timer_disable,
938 	.get_fclk = omap_dm_timer_get_fclk,
939 	.start = omap_dm_timer_start,
940 	.stop = omap_dm_timer_stop,
941 	.set_load = omap_dm_timer_set_load,
942 	.set_match = omap_dm_timer_set_match,
943 	.set_pwm = omap_dm_timer_set_pwm,
944 	.set_prescaler = omap_dm_timer_set_prescaler,
945 	.read_counter = omap_dm_timer_read_counter,
946 	.write_counter = omap_dm_timer_write_counter,
947 	.read_status = omap_dm_timer_read_status,
948 	.write_status = omap_dm_timer_write_status,
949 };
950 
951 static const struct dmtimer_platform_data omap3plus_pdata = {
952 	.timer_errata = OMAP_TIMER_ERRATA_I103_I767,
953 	.timer_ops = &dmtimer_ops,
954 };
955 
956 static const struct of_device_id omap_timer_match[] = {
957 	{
958 		.compatible = "ti,omap2420-timer",
959 	},
960 	{
961 		.compatible = "ti,omap3430-timer",
962 		.data = &omap3plus_pdata,
963 	},
964 	{
965 		.compatible = "ti,omap4430-timer",
966 		.data = &omap3plus_pdata,
967 	},
968 	{
969 		.compatible = "ti,omap5430-timer",
970 		.data = &omap3plus_pdata,
971 	},
972 	{
973 		.compatible = "ti,am335x-timer",
974 		.data = &omap3plus_pdata,
975 	},
976 	{
977 		.compatible = "ti,am335x-timer-1ms",
978 		.data = &omap3plus_pdata,
979 	},
980 	{
981 		.compatible = "ti,dm816-timer",
982 		.data = &omap3plus_pdata,
983 	},
984 	{},
985 };
986 MODULE_DEVICE_TABLE(of, omap_timer_match);
987 
988 static struct platform_driver omap_dm_timer_driver = {
989 	.probe  = omap_dm_timer_probe,
990 	.remove = omap_dm_timer_remove,
991 	.driver = {
992 		.name   = "omap_timer",
993 		.of_match_table = of_match_ptr(omap_timer_match),
994 	},
995 };
996 
997 module_platform_driver(omap_dm_timer_driver);
998 
999 MODULE_DESCRIPTION("OMAP Dual-Mode Timer Driver");
1000 MODULE_LICENSE("GPL");
1001 MODULE_ALIAS("platform:" DRIVER_NAME);
1002 MODULE_AUTHOR("Texas Instruments Inc");
1003