1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * linux/arch/arm/plat-omap/dmtimer.c
4  *
5  * OMAP Dual-Mode Timers
6  *
7  * Copyright (C) 2010 Texas Instruments Incorporated - https://www.ti.com/
8  * Tarun Kanti DebBarma <tarun.kanti@ti.com>
9  * Thara Gopinath <thara@ti.com>
10  *
11  * dmtimer adaptation to platform_driver.
12  *
13  * Copyright (C) 2005 Nokia Corporation
14  * OMAP2 support by Juha Yrjola
15  * API improvements and OMAP2 clock framework support by Timo Teras
16  *
17  * Copyright (C) 2009 Texas Instruments
18  * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
19  */
20 
21 #include <linux/clk.h>
22 #include <linux/clk-provider.h>
23 #include <linux/cpu_pm.h>
24 #include <linux/module.h>
25 #include <linux/io.h>
26 #include <linux/device.h>
27 #include <linux/err.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/of.h>
30 #include <linux/platform_device.h>
31 #include <linux/platform_data/dmtimer-omap.h>
32 
33 #include <clocksource/timer-ti-dm.h>
34 
35 /*
36  * timer errata flags
37  *
38  * Errata i103/i767 impacts all OMAP3/4/5 devices including AM33xx. This
39  * errata prevents us from using posted mode on these devices, unless the
40  * timer counter register is never read. For more details please refer to
41  * the OMAP3/4/5 errata documents.
42  */
43 #define OMAP_TIMER_ERRATA_I103_I767			0x80000000
44 
45 /* posted mode types */
46 #define OMAP_TIMER_NONPOSTED			0x00
47 #define OMAP_TIMER_POSTED			0x01
48 
49 /* register offsets with the write pending bit encoded */
50 #define	WPSHIFT					16
51 
52 #define OMAP_TIMER_WAKEUP_EN_REG		(_OMAP_TIMER_WAKEUP_EN_OFFSET \
53 							| (WP_NONE << WPSHIFT))
54 
55 #define OMAP_TIMER_CTRL_REG			(_OMAP_TIMER_CTRL_OFFSET \
56 							| (WP_TCLR << WPSHIFT))
57 
58 #define OMAP_TIMER_COUNTER_REG			(_OMAP_TIMER_COUNTER_OFFSET \
59 							| (WP_TCRR << WPSHIFT))
60 
61 #define OMAP_TIMER_LOAD_REG			(_OMAP_TIMER_LOAD_OFFSET \
62 							| (WP_TLDR << WPSHIFT))
63 
64 #define OMAP_TIMER_TRIGGER_REG			(_OMAP_TIMER_TRIGGER_OFFSET \
65 							| (WP_TTGR << WPSHIFT))
66 
67 #define OMAP_TIMER_WRITE_PEND_REG		(_OMAP_TIMER_WRITE_PEND_OFFSET \
68 							| (WP_NONE << WPSHIFT))
69 
70 #define OMAP_TIMER_MATCH_REG			(_OMAP_TIMER_MATCH_OFFSET \
71 							| (WP_TMAR << WPSHIFT))
72 
73 #define OMAP_TIMER_CAPTURE_REG			(_OMAP_TIMER_CAPTURE_OFFSET \
74 							| (WP_NONE << WPSHIFT))
75 
76 #define OMAP_TIMER_IF_CTRL_REG			(_OMAP_TIMER_IF_CTRL_OFFSET \
77 							| (WP_NONE << WPSHIFT))
78 
79 #define OMAP_TIMER_CAPTURE2_REG			(_OMAP_TIMER_CAPTURE2_OFFSET \
80 							| (WP_NONE << WPSHIFT))
81 
82 #define OMAP_TIMER_TICK_POS_REG			(_OMAP_TIMER_TICK_POS_OFFSET \
83 							| (WP_TPIR << WPSHIFT))
84 
85 #define OMAP_TIMER_TICK_NEG_REG			(_OMAP_TIMER_TICK_NEG_OFFSET \
86 							| (WP_TNIR << WPSHIFT))
87 
88 #define OMAP_TIMER_TICK_COUNT_REG		(_OMAP_TIMER_TICK_COUNT_OFFSET \
89 							| (WP_TCVR << WPSHIFT))
90 
91 #define OMAP_TIMER_TICK_INT_MASK_SET_REG				\
92 		(_OMAP_TIMER_TICK_INT_MASK_SET_OFFSET | (WP_TOCR << WPSHIFT))
93 
94 #define OMAP_TIMER_TICK_INT_MASK_COUNT_REG				\
95 		(_OMAP_TIMER_TICK_INT_MASK_COUNT_OFFSET | (WP_TOWR << WPSHIFT))
96 
97 struct timer_regs {
98 	u32 ocp_cfg;
99 	u32 tidr;
100 	u32 tier;
101 	u32 twer;
102 	u32 tclr;
103 	u32 tcrr;
104 	u32 tldr;
105 	u32 ttrg;
106 	u32 twps;
107 	u32 tmar;
108 	u32 tcar1;
109 	u32 tsicr;
110 	u32 tcar2;
111 	u32 tpir;
112 	u32 tnir;
113 	u32 tcvr;
114 	u32 tocr;
115 	u32 towr;
116 };
117 
118 struct dmtimer {
119 	struct omap_dm_timer cookie;
120 	int id;
121 	int irq;
122 	struct clk *fclk;
123 
124 	void __iomem	*io_base;
125 	int		irq_stat;	/* TISR/IRQSTATUS interrupt status */
126 	int		irq_ena;	/* irq enable */
127 	int		irq_dis;	/* irq disable, only on v2 ip */
128 	void __iomem	*pend;		/* write pending */
129 	void __iomem	*func_base;	/* function register base */
130 
131 	atomic_t enabled;
132 	unsigned long rate;
133 	unsigned reserved:1;
134 	unsigned posted:1;
135 	unsigned omap1:1;
136 	struct timer_regs context;
137 	int revision;
138 	u32 capability;
139 	u32 errata;
140 	struct platform_device *pdev;
141 	struct list_head node;
142 	struct notifier_block nb;
143 };
144 
145 static u32 omap_reserved_systimers;
146 static LIST_HEAD(omap_timer_list);
147 static DEFINE_SPINLOCK(dm_timer_lock);
148 
149 enum {
150 	REQUEST_ANY = 0,
151 	REQUEST_BY_ID,
152 	REQUEST_BY_CAP,
153 	REQUEST_BY_NODE,
154 };
155 
156 /**
157  * dmtimer_read - read timer registers in posted and non-posted mode
158  * @timer:	timer pointer over which read operation to perform
159  * @reg:	lowest byte holds the register offset
160  *
161  * The posted mode bit is encoded in reg. Note that in posted mode, write
162  * pending bit must be checked. Otherwise a read of a non completed write
163  * will produce an error.
164  */
165 static inline u32 dmtimer_read(struct dmtimer *timer, u32 reg)
166 {
167 	u16 wp, offset;
168 
169 	wp = reg >> WPSHIFT;
170 	offset = reg & 0xff;
171 
172 	/* Wait for a possible write pending bit in posted mode */
173 	if (wp && timer->posted)
174 		while (readl_relaxed(timer->pend) & wp)
175 			cpu_relax();
176 
177 	return readl_relaxed(timer->func_base + offset);
178 }
179 
180 /**
181  * dmtimer_write - write timer registers in posted and non-posted mode
182  * @timer:      timer pointer over which write operation is to perform
183  * @reg:        lowest byte holds the register offset
184  * @value:      data to write into the register
185  *
186  * The posted mode bit is encoded in reg. Note that in posted mode, the write
187  * pending bit must be checked. Otherwise a write on a register which has a
188  * pending write will be lost.
189  */
190 static inline void dmtimer_write(struct dmtimer *timer, u32 reg, u32 val)
191 {
192 	u16 wp, offset;
193 
194 	wp = reg >> WPSHIFT;
195 	offset = reg & 0xff;
196 
197 	/* Wait for a possible write pending bit in posted mode */
198 	if (wp && timer->posted)
199 		while (readl_relaxed(timer->pend) & wp)
200 			cpu_relax();
201 
202 	writel_relaxed(val, timer->func_base + offset);
203 }
204 
205 static inline void __omap_dm_timer_init_regs(struct dmtimer *timer)
206 {
207 	u32 tidr;
208 
209 	/* Assume v1 ip if bits [31:16] are zero */
210 	tidr = readl_relaxed(timer->io_base);
211 	if (!(tidr >> 16)) {
212 		timer->revision = 1;
213 		timer->irq_stat = OMAP_TIMER_V1_STAT_OFFSET;
214 		timer->irq_ena = OMAP_TIMER_V1_INT_EN_OFFSET;
215 		timer->irq_dis = OMAP_TIMER_V1_INT_EN_OFFSET;
216 		timer->pend = timer->io_base + _OMAP_TIMER_WRITE_PEND_OFFSET;
217 		timer->func_base = timer->io_base;
218 	} else {
219 		timer->revision = 2;
220 		timer->irq_stat = OMAP_TIMER_V2_IRQSTATUS - OMAP_TIMER_V2_FUNC_OFFSET;
221 		timer->irq_ena = OMAP_TIMER_V2_IRQENABLE_SET - OMAP_TIMER_V2_FUNC_OFFSET;
222 		timer->irq_dis = OMAP_TIMER_V2_IRQENABLE_CLR - OMAP_TIMER_V2_FUNC_OFFSET;
223 		timer->pend = timer->io_base +
224 			_OMAP_TIMER_WRITE_PEND_OFFSET +
225 				OMAP_TIMER_V2_FUNC_OFFSET;
226 		timer->func_base = timer->io_base + OMAP_TIMER_V2_FUNC_OFFSET;
227 	}
228 }
229 
230 /*
231  * __omap_dm_timer_enable_posted - enables write posted mode
232  * @timer:      pointer to timer instance handle
233  *
234  * Enables the write posted mode for the timer. When posted mode is enabled
235  * writes to certain timer registers are immediately acknowledged by the
236  * internal bus and hence prevents stalling the CPU waiting for the write to
237  * complete. Enabling this feature can improve performance for writing to the
238  * timer registers.
239  */
240 static inline void __omap_dm_timer_enable_posted(struct dmtimer *timer)
241 {
242 	if (timer->posted)
243 		return;
244 
245 	if (timer->errata & OMAP_TIMER_ERRATA_I103_I767) {
246 		timer->posted = OMAP_TIMER_NONPOSTED;
247 		dmtimer_write(timer, OMAP_TIMER_IF_CTRL_REG, 0);
248 		return;
249 	}
250 
251 	dmtimer_write(timer, OMAP_TIMER_IF_CTRL_REG, OMAP_TIMER_CTRL_POSTED);
252 	timer->context.tsicr = OMAP_TIMER_CTRL_POSTED;
253 	timer->posted = OMAP_TIMER_POSTED;
254 }
255 
256 static inline void __omap_dm_timer_stop(struct dmtimer *timer,
257 					unsigned long rate)
258 {
259 	u32 l;
260 
261 	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
262 	if (l & OMAP_TIMER_CTRL_ST) {
263 		l &= ~0x1;
264 		dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
265 #ifdef CONFIG_ARCH_OMAP2PLUS
266 		/* Readback to make sure write has completed */
267 		dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
268 		/*
269 		 * Wait for functional clock period x 3.5 to make sure that
270 		 * timer is stopped
271 		 */
272 		udelay(3500000 / rate + 1);
273 #endif
274 	}
275 
276 	/* Ack possibly pending interrupt */
277 	dmtimer_write(timer, timer->irq_stat, OMAP_TIMER_INT_OVERFLOW);
278 }
279 
280 static inline void __omap_dm_timer_int_enable(struct dmtimer *timer,
281 					      unsigned int value)
282 {
283 	dmtimer_write(timer, timer->irq_ena, value);
284 	dmtimer_write(timer, OMAP_TIMER_WAKEUP_EN_REG, value);
285 }
286 
287 static inline unsigned int
288 __omap_dm_timer_read_counter(struct dmtimer *timer)
289 {
290 	return dmtimer_read(timer, OMAP_TIMER_COUNTER_REG);
291 }
292 
293 static inline void __omap_dm_timer_write_status(struct dmtimer *timer,
294 						unsigned int value)
295 {
296 	dmtimer_write(timer, timer->irq_stat, value);
297 }
298 
299 static void omap_timer_restore_context(struct dmtimer *timer)
300 {
301 	dmtimer_write(timer, OMAP_TIMER_OCP_CFG_OFFSET, timer->context.ocp_cfg);
302 
303 	dmtimer_write(timer, OMAP_TIMER_WAKEUP_EN_REG, timer->context.twer);
304 	dmtimer_write(timer, OMAP_TIMER_COUNTER_REG, timer->context.tcrr);
305 	dmtimer_write(timer, OMAP_TIMER_LOAD_REG, timer->context.tldr);
306 	dmtimer_write(timer, OMAP_TIMER_MATCH_REG, timer->context.tmar);
307 	dmtimer_write(timer, OMAP_TIMER_IF_CTRL_REG, timer->context.tsicr);
308 	dmtimer_write(timer, timer->irq_ena, timer->context.tier);
309 	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, timer->context.tclr);
310 }
311 
312 static void omap_timer_save_context(struct dmtimer *timer)
313 {
314 	timer->context.ocp_cfg = dmtimer_read(timer, OMAP_TIMER_OCP_CFG_OFFSET);
315 
316 	timer->context.tclr = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
317 	timer->context.twer = dmtimer_read(timer, OMAP_TIMER_WAKEUP_EN_REG);
318 	timer->context.tldr = dmtimer_read(timer, OMAP_TIMER_LOAD_REG);
319 	timer->context.tmar = dmtimer_read(timer, OMAP_TIMER_MATCH_REG);
320 	timer->context.tier = dmtimer_read(timer, timer->irq_ena);
321 	timer->context.tsicr = dmtimer_read(timer, OMAP_TIMER_IF_CTRL_REG);
322 }
323 
324 static int omap_timer_context_notifier(struct notifier_block *nb,
325 				       unsigned long cmd, void *v)
326 {
327 	struct dmtimer *timer;
328 
329 	timer = container_of(nb, struct dmtimer, nb);
330 
331 	switch (cmd) {
332 	case CPU_CLUSTER_PM_ENTER:
333 		if ((timer->capability & OMAP_TIMER_ALWON) ||
334 		    !atomic_read(&timer->enabled))
335 			break;
336 		omap_timer_save_context(timer);
337 		break;
338 	case CPU_CLUSTER_PM_ENTER_FAILED:	/* No need to restore context */
339 		break;
340 	case CPU_CLUSTER_PM_EXIT:
341 		if ((timer->capability & OMAP_TIMER_ALWON) ||
342 		    !atomic_read(&timer->enabled))
343 			break;
344 		omap_timer_restore_context(timer);
345 		break;
346 	}
347 
348 	return NOTIFY_OK;
349 }
350 
351 static int omap_dm_timer_reset(struct dmtimer *timer)
352 {
353 	u32 l, timeout = 100000;
354 
355 	if (timer->revision != 1)
356 		return -EINVAL;
357 
358 	dmtimer_write(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
359 
360 	do {
361 		l = dmtimer_read(timer, OMAP_TIMER_V1_SYS_STAT_OFFSET);
362 	} while (!l && timeout--);
363 
364 	if (!timeout) {
365 		dev_err(&timer->pdev->dev, "Timer failed to reset\n");
366 		return -ETIMEDOUT;
367 	}
368 
369 	/* Configure timer for smart-idle mode */
370 	l = dmtimer_read(timer, OMAP_TIMER_OCP_CFG_OFFSET);
371 	l |= 0x2 << 0x3;
372 	dmtimer_write(timer, OMAP_TIMER_OCP_CFG_OFFSET, l);
373 
374 	timer->posted = 0;
375 
376 	return 0;
377 }
378 
379 /*
380  * Functions exposed to PWM and remoteproc drivers via platform_data.
381  * Do not use these in the driver, these will get deprecated and will
382  * will be replaced by Linux generic framework functions such as
383  * chained interrupts and clock framework.
384  */
385 static struct dmtimer *to_dmtimer(struct omap_dm_timer *cookie)
386 {
387 	if (!cookie)
388 		return NULL;
389 
390 	return container_of(cookie, struct dmtimer, cookie);
391 }
392 
393 static int omap_dm_timer_set_source(struct omap_dm_timer *cookie, int source)
394 {
395 	int ret;
396 	const char *parent_name;
397 	struct clk *parent;
398 	struct dmtimer_platform_data *pdata;
399 	struct dmtimer *timer;
400 
401 	timer = to_dmtimer(cookie);
402 	if (unlikely(!timer) || IS_ERR(timer->fclk))
403 		return -EINVAL;
404 
405 	switch (source) {
406 	case OMAP_TIMER_SRC_SYS_CLK:
407 		parent_name = "timer_sys_ck";
408 		break;
409 	case OMAP_TIMER_SRC_32_KHZ:
410 		parent_name = "timer_32k_ck";
411 		break;
412 	case OMAP_TIMER_SRC_EXT_CLK:
413 		parent_name = "timer_ext_ck";
414 		break;
415 	default:
416 		return -EINVAL;
417 	}
418 
419 	pdata = timer->pdev->dev.platform_data;
420 
421 	/*
422 	 * FIXME: Used for OMAP1 devices only because they do not currently
423 	 * use the clock framework to set the parent clock. To be removed
424 	 * once OMAP1 migrated to using clock framework for dmtimers
425 	 */
426 	if (timer->omap1 && pdata && pdata->set_timer_src)
427 		return pdata->set_timer_src(timer->pdev, source);
428 
429 #if defined(CONFIG_COMMON_CLK)
430 	/* Check if the clock has configurable parents */
431 	if (clk_hw_get_num_parents(__clk_get_hw(timer->fclk)) < 2)
432 		return 0;
433 #endif
434 
435 	parent = clk_get(&timer->pdev->dev, parent_name);
436 	if (IS_ERR(parent)) {
437 		pr_err("%s: %s not found\n", __func__, parent_name);
438 		return -EINVAL;
439 	}
440 
441 	ret = clk_set_parent(timer->fclk, parent);
442 	if (ret < 0)
443 		pr_err("%s: failed to set %s as parent\n", __func__,
444 			parent_name);
445 
446 	clk_put(parent);
447 
448 	return ret;
449 }
450 
451 static void omap_dm_timer_enable(struct omap_dm_timer *cookie)
452 {
453 	struct dmtimer *timer = to_dmtimer(cookie);
454 	struct device *dev = &timer->pdev->dev;
455 	int rc;
456 
457 	rc = pm_runtime_resume_and_get(dev);
458 	if (rc)
459 		dev_err(dev, "could not enable timer\n");
460 }
461 
462 static void omap_dm_timer_disable(struct omap_dm_timer *cookie)
463 {
464 	struct dmtimer *timer = to_dmtimer(cookie);
465 	struct device *dev = &timer->pdev->dev;
466 
467 	pm_runtime_put_sync(dev);
468 }
469 
470 static int omap_dm_timer_prepare(struct dmtimer *timer)
471 {
472 	struct device *dev = &timer->pdev->dev;
473 	int rc;
474 
475 	rc = pm_runtime_resume_and_get(dev);
476 	if (rc)
477 		return rc;
478 
479 	if (timer->capability & OMAP_TIMER_NEEDS_RESET) {
480 		rc = omap_dm_timer_reset(timer);
481 		if (rc) {
482 			pm_runtime_put_sync(dev);
483 			return rc;
484 		}
485 	}
486 
487 	__omap_dm_timer_enable_posted(timer);
488 	pm_runtime_put_sync(dev);
489 
490 	return 0;
491 }
492 
493 static inline u32 omap_dm_timer_reserved_systimer(int id)
494 {
495 	return (omap_reserved_systimers & (1 << (id - 1))) ? 1 : 0;
496 }
497 
498 static struct dmtimer *_omap_dm_timer_request(int req_type, void *data)
499 {
500 	struct dmtimer *timer = NULL, *t;
501 	struct device_node *np = NULL;
502 	unsigned long flags;
503 	u32 cap = 0;
504 	int id = 0;
505 
506 	switch (req_type) {
507 	case REQUEST_BY_ID:
508 		id = *(int *)data;
509 		break;
510 	case REQUEST_BY_CAP:
511 		cap = *(u32 *)data;
512 		break;
513 	case REQUEST_BY_NODE:
514 		np = (struct device_node *)data;
515 		break;
516 	default:
517 		/* REQUEST_ANY */
518 		break;
519 	}
520 
521 	spin_lock_irqsave(&dm_timer_lock, flags);
522 	list_for_each_entry(t, &omap_timer_list, node) {
523 		if (t->reserved)
524 			continue;
525 
526 		switch (req_type) {
527 		case REQUEST_BY_ID:
528 			if (id == t->pdev->id) {
529 				timer = t;
530 				timer->reserved = 1;
531 				goto found;
532 			}
533 			break;
534 		case REQUEST_BY_CAP:
535 			if (cap == (t->capability & cap)) {
536 				/*
537 				 * If timer is not NULL, we have already found
538 				 * one timer. But it was not an exact match
539 				 * because it had more capabilities than what
540 				 * was required. Therefore, unreserve the last
541 				 * timer found and see if this one is a better
542 				 * match.
543 				 */
544 				if (timer)
545 					timer->reserved = 0;
546 				timer = t;
547 				timer->reserved = 1;
548 
549 				/* Exit loop early if we find an exact match */
550 				if (t->capability == cap)
551 					goto found;
552 			}
553 			break;
554 		case REQUEST_BY_NODE:
555 			if (np == t->pdev->dev.of_node) {
556 				timer = t;
557 				timer->reserved = 1;
558 				goto found;
559 			}
560 			break;
561 		default:
562 			/* REQUEST_ANY */
563 			timer = t;
564 			timer->reserved = 1;
565 			goto found;
566 		}
567 	}
568 found:
569 	spin_unlock_irqrestore(&dm_timer_lock, flags);
570 
571 	if (timer && omap_dm_timer_prepare(timer)) {
572 		timer->reserved = 0;
573 		timer = NULL;
574 	}
575 
576 	if (!timer)
577 		pr_debug("%s: timer request failed!\n", __func__);
578 
579 	return timer;
580 }
581 
582 static struct omap_dm_timer *omap_dm_timer_request(void)
583 {
584 	struct dmtimer *timer;
585 
586 	timer = _omap_dm_timer_request(REQUEST_ANY, NULL);
587 	if (!timer)
588 		return NULL;
589 
590 	return &timer->cookie;
591 }
592 
593 static struct omap_dm_timer *omap_dm_timer_request_specific(int id)
594 {
595 	struct dmtimer *timer;
596 
597 	/* Requesting timer by ID is not supported when device tree is used */
598 	if (of_have_populated_dt()) {
599 		pr_warn("%s: Please use omap_dm_timer_request_by_node()\n",
600 			__func__);
601 		return NULL;
602 	}
603 
604 	timer = _omap_dm_timer_request(REQUEST_BY_ID, &id);
605 	if (!timer)
606 		return NULL;
607 
608 	return &timer->cookie;
609 }
610 
611 /**
612  * omap_dm_timer_request_by_node - Request a timer by device-tree node
613  * @np:		Pointer to device-tree timer node
614  *
615  * Request a timer based upon a device node pointer. Returns pointer to
616  * timer handle on success and a NULL pointer on failure.
617  */
618 static struct omap_dm_timer *omap_dm_timer_request_by_node(struct device_node *np)
619 {
620 	struct dmtimer *timer;
621 
622 	if (!np)
623 		return NULL;
624 
625 	timer = _omap_dm_timer_request(REQUEST_BY_NODE, np);
626 	if (!timer)
627 		return NULL;
628 
629 	return &timer->cookie;
630 }
631 
632 static int omap_dm_timer_free(struct omap_dm_timer *cookie)
633 {
634 	struct dmtimer *timer;
635 	struct device *dev;
636 	int rc;
637 
638 	timer = to_dmtimer(cookie);
639 	if (unlikely(!timer))
640 		return -EINVAL;
641 
642 	WARN_ON(!timer->reserved);
643 	timer->reserved = 0;
644 
645 	dev = &timer->pdev->dev;
646 	rc = pm_runtime_resume_and_get(dev);
647 	if (rc)
648 		return rc;
649 
650 	/* Clear timer configuration */
651 	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, 0);
652 
653 	pm_runtime_put_sync(dev);
654 
655 	return 0;
656 }
657 
658 static int omap_dm_timer_get_irq(struct omap_dm_timer *cookie)
659 {
660 	struct dmtimer *timer = to_dmtimer(cookie);
661 	if (timer)
662 		return timer->irq;
663 	return -EINVAL;
664 }
665 
666 #if defined(CONFIG_ARCH_OMAP1)
667 #include <linux/soc/ti/omap1-io.h>
668 
669 static struct clk *omap_dm_timer_get_fclk(struct omap_dm_timer *cookie)
670 {
671 	return NULL;
672 }
673 
674 /**
675  * omap_dm_timer_modify_idlect_mask - Check if any running timers use ARMXOR
676  * @inputmask: current value of idlect mask
677  */
678 __u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
679 {
680 	int i = 0;
681 	struct dmtimer *timer = NULL;
682 	unsigned long flags;
683 
684 	/* If ARMXOR cannot be idled this function call is unnecessary */
685 	if (!(inputmask & (1 << 1)))
686 		return inputmask;
687 
688 	/* If any active timer is using ARMXOR return modified mask */
689 	spin_lock_irqsave(&dm_timer_lock, flags);
690 	list_for_each_entry(timer, &omap_timer_list, node) {
691 		u32 l;
692 
693 		l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
694 		if (l & OMAP_TIMER_CTRL_ST) {
695 			if (((omap_readl(MOD_CONF_CTRL_1) >> (i * 2)) & 0x03) == 0)
696 				inputmask &= ~(1 << 1);
697 			else
698 				inputmask &= ~(1 << 2);
699 		}
700 		i++;
701 	}
702 	spin_unlock_irqrestore(&dm_timer_lock, flags);
703 
704 	return inputmask;
705 }
706 
707 #else
708 
709 static struct clk *omap_dm_timer_get_fclk(struct omap_dm_timer *cookie)
710 {
711 	struct dmtimer *timer = to_dmtimer(cookie);
712 
713 	if (timer && !IS_ERR(timer->fclk))
714 		return timer->fclk;
715 	return NULL;
716 }
717 
718 __u32 omap_dm_timer_modify_idlect_mask(__u32 inputmask)
719 {
720 	BUG();
721 
722 	return 0;
723 }
724 
725 #endif
726 
727 static int omap_dm_timer_start(struct omap_dm_timer *cookie)
728 {
729 	struct dmtimer *timer;
730 	struct device *dev;
731 	int rc;
732 	u32 l;
733 
734 	timer = to_dmtimer(cookie);
735 	if (unlikely(!timer))
736 		return -EINVAL;
737 
738 	dev = &timer->pdev->dev;
739 
740 	rc = pm_runtime_resume_and_get(dev);
741 	if (rc)
742 		return rc;
743 
744 	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
745 	if (!(l & OMAP_TIMER_CTRL_ST)) {
746 		l |= OMAP_TIMER_CTRL_ST;
747 		dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
748 	}
749 
750 	return 0;
751 }
752 
753 static int omap_dm_timer_stop(struct omap_dm_timer *cookie)
754 {
755 	struct dmtimer *timer;
756 	struct device *dev;
757 	unsigned long rate = 0;
758 
759 	timer = to_dmtimer(cookie);
760 	if (unlikely(!timer))
761 		return -EINVAL;
762 
763 	dev = &timer->pdev->dev;
764 
765 	if (!timer->omap1)
766 		rate = clk_get_rate(timer->fclk);
767 
768 	__omap_dm_timer_stop(timer, rate);
769 
770 	pm_runtime_put_sync(dev);
771 
772 	return 0;
773 }
774 
775 static int omap_dm_timer_set_load(struct omap_dm_timer *cookie,
776 				  unsigned int load)
777 {
778 	struct dmtimer *timer;
779 	struct device *dev;
780 	int rc;
781 
782 	timer = to_dmtimer(cookie);
783 	if (unlikely(!timer))
784 		return -EINVAL;
785 
786 	dev = &timer->pdev->dev;
787 	rc = pm_runtime_resume_and_get(dev);
788 	if (rc)
789 		return rc;
790 
791 	dmtimer_write(timer, OMAP_TIMER_LOAD_REG, load);
792 
793 	pm_runtime_put_sync(dev);
794 
795 	return 0;
796 }
797 
798 static int omap_dm_timer_set_match(struct omap_dm_timer *cookie, int enable,
799 				   unsigned int match)
800 {
801 	struct dmtimer *timer;
802 	struct device *dev;
803 	int rc;
804 	u32 l;
805 
806 	timer = to_dmtimer(cookie);
807 	if (unlikely(!timer))
808 		return -EINVAL;
809 
810 	dev = &timer->pdev->dev;
811 	rc = pm_runtime_resume_and_get(dev);
812 	if (rc)
813 		return rc;
814 
815 	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
816 	if (enable)
817 		l |= OMAP_TIMER_CTRL_CE;
818 	else
819 		l &= ~OMAP_TIMER_CTRL_CE;
820 	dmtimer_write(timer, OMAP_TIMER_MATCH_REG, match);
821 	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
822 
823 	pm_runtime_put_sync(dev);
824 
825 	return 0;
826 }
827 
828 static int omap_dm_timer_set_pwm(struct omap_dm_timer *cookie, int def_on,
829 				 int toggle, int trigger, int autoreload)
830 {
831 	struct dmtimer *timer;
832 	struct device *dev;
833 	int rc;
834 	u32 l;
835 
836 	timer = to_dmtimer(cookie);
837 	if (unlikely(!timer))
838 		return -EINVAL;
839 
840 	dev = &timer->pdev->dev;
841 	rc = pm_runtime_resume_and_get(dev);
842 	if (rc)
843 		return rc;
844 
845 	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
846 	l &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM |
847 	       OMAP_TIMER_CTRL_PT | (0x03 << 10) | OMAP_TIMER_CTRL_AR);
848 	if (def_on)
849 		l |= OMAP_TIMER_CTRL_SCPWM;
850 	if (toggle)
851 		l |= OMAP_TIMER_CTRL_PT;
852 	l |= trigger << 10;
853 	if (autoreload)
854 		l |= OMAP_TIMER_CTRL_AR;
855 	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
856 
857 	pm_runtime_put_sync(dev);
858 
859 	return 0;
860 }
861 
862 static int omap_dm_timer_get_pwm_status(struct omap_dm_timer *cookie)
863 {
864 	struct dmtimer *timer;
865 	struct device *dev;
866 	int rc;
867 	u32 l;
868 
869 	timer = to_dmtimer(cookie);
870 	if (unlikely(!timer))
871 		return -EINVAL;
872 
873 	dev = &timer->pdev->dev;
874 	rc = pm_runtime_resume_and_get(dev);
875 	if (rc)
876 		return rc;
877 
878 	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
879 
880 	pm_runtime_put_sync(dev);
881 
882 	return l;
883 }
884 
885 static int omap_dm_timer_set_prescaler(struct omap_dm_timer *cookie,
886 				       int prescaler)
887 {
888 	struct dmtimer *timer;
889 	struct device *dev;
890 	int rc;
891 	u32 l;
892 
893 	timer = to_dmtimer(cookie);
894 	if (unlikely(!timer) || prescaler < -1 || prescaler > 7)
895 		return -EINVAL;
896 
897 	dev = &timer->pdev->dev;
898 	rc = pm_runtime_resume_and_get(dev);
899 	if (rc)
900 		return rc;
901 
902 	l = dmtimer_read(timer, OMAP_TIMER_CTRL_REG);
903 	l &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2));
904 	if (prescaler >= 0) {
905 		l |= OMAP_TIMER_CTRL_PRE;
906 		l |= prescaler << 2;
907 	}
908 	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, l);
909 
910 	pm_runtime_put_sync(dev);
911 
912 	return 0;
913 }
914 
915 static int omap_dm_timer_set_int_enable(struct omap_dm_timer *cookie,
916 					unsigned int value)
917 {
918 	struct dmtimer *timer;
919 	struct device *dev;
920 	int rc;
921 
922 	timer = to_dmtimer(cookie);
923 	if (unlikely(!timer))
924 		return -EINVAL;
925 
926 	dev = &timer->pdev->dev;
927 	rc = pm_runtime_resume_and_get(dev);
928 	if (rc)
929 		return rc;
930 
931 	__omap_dm_timer_int_enable(timer, value);
932 
933 	pm_runtime_put_sync(dev);
934 
935 	return 0;
936 }
937 
938 /**
939  * omap_dm_timer_set_int_disable - disable timer interrupts
940  * @timer:	pointer to timer handle
941  * @mask:	bit mask of interrupts to be disabled
942  *
943  * Disables the specified timer interrupts for a timer.
944  */
945 static int omap_dm_timer_set_int_disable(struct omap_dm_timer *cookie, u32 mask)
946 {
947 	struct dmtimer *timer;
948 	struct device *dev;
949 	u32 l = mask;
950 	int rc;
951 
952 	timer = to_dmtimer(cookie);
953 	if (unlikely(!timer))
954 		return -EINVAL;
955 
956 	dev = &timer->pdev->dev;
957 	rc = pm_runtime_resume_and_get(dev);
958 	if (rc)
959 		return rc;
960 
961 	if (timer->revision == 1)
962 		l = dmtimer_read(timer, timer->irq_ena) & ~mask;
963 
964 	dmtimer_write(timer, timer->irq_dis, l);
965 	l = dmtimer_read(timer, OMAP_TIMER_WAKEUP_EN_REG) & ~mask;
966 	dmtimer_write(timer, OMAP_TIMER_WAKEUP_EN_REG, l);
967 
968 	pm_runtime_put_sync(dev);
969 
970 	return 0;
971 }
972 
973 static unsigned int omap_dm_timer_read_status(struct omap_dm_timer *cookie)
974 {
975 	struct dmtimer *timer;
976 	unsigned int l;
977 
978 	timer = to_dmtimer(cookie);
979 	if (unlikely(!timer || !atomic_read(&timer->enabled))) {
980 		pr_err("%s: timer not available or enabled.\n", __func__);
981 		return 0;
982 	}
983 
984 	l = dmtimer_read(timer, timer->irq_stat);
985 
986 	return l;
987 }
988 
989 static int omap_dm_timer_write_status(struct omap_dm_timer *cookie, unsigned int value)
990 {
991 	struct dmtimer *timer;
992 
993 	timer = to_dmtimer(cookie);
994 	if (unlikely(!timer || !atomic_read(&timer->enabled)))
995 		return -EINVAL;
996 
997 	__omap_dm_timer_write_status(timer, value);
998 
999 	return 0;
1000 }
1001 
1002 static unsigned int omap_dm_timer_read_counter(struct omap_dm_timer *cookie)
1003 {
1004 	struct dmtimer *timer;
1005 
1006 	timer = to_dmtimer(cookie);
1007 	if (unlikely(!timer || !atomic_read(&timer->enabled))) {
1008 		pr_err("%s: timer not iavailable or enabled.\n", __func__);
1009 		return 0;
1010 	}
1011 
1012 	return __omap_dm_timer_read_counter(timer);
1013 }
1014 
1015 static int omap_dm_timer_write_counter(struct omap_dm_timer *cookie, unsigned int value)
1016 {
1017 	struct dmtimer *timer;
1018 
1019 	timer = to_dmtimer(cookie);
1020 	if (unlikely(!timer || !atomic_read(&timer->enabled))) {
1021 		pr_err("%s: timer not available or enabled.\n", __func__);
1022 		return -EINVAL;
1023 	}
1024 
1025 	dmtimer_write(timer, OMAP_TIMER_COUNTER_REG, value);
1026 
1027 	/* Save the context */
1028 	timer->context.tcrr = value;
1029 	return 0;
1030 }
1031 
1032 static int __maybe_unused omap_dm_timer_runtime_suspend(struct device *dev)
1033 {
1034 	struct dmtimer *timer = dev_get_drvdata(dev);
1035 
1036 	atomic_set(&timer->enabled, 0);
1037 
1038 	if (timer->capability & OMAP_TIMER_ALWON || !timer->func_base)
1039 		return 0;
1040 
1041 	omap_timer_save_context(timer);
1042 
1043 	return 0;
1044 }
1045 
1046 static int __maybe_unused omap_dm_timer_runtime_resume(struct device *dev)
1047 {
1048 	struct dmtimer *timer = dev_get_drvdata(dev);
1049 
1050 	if (!(timer->capability & OMAP_TIMER_ALWON) && timer->func_base)
1051 		omap_timer_restore_context(timer);
1052 
1053 	atomic_set(&timer->enabled, 1);
1054 
1055 	return 0;
1056 }
1057 
1058 static const struct dev_pm_ops omap_dm_timer_pm_ops = {
1059 	SET_RUNTIME_PM_OPS(omap_dm_timer_runtime_suspend,
1060 			   omap_dm_timer_runtime_resume, NULL)
1061 };
1062 
1063 static const struct of_device_id omap_timer_match[];
1064 
1065 /**
1066  * omap_dm_timer_probe - probe function called for every registered device
1067  * @pdev:	pointer to current timer platform device
1068  *
1069  * Called by driver framework at the end of device registration for all
1070  * timer devices.
1071  */
1072 static int omap_dm_timer_probe(struct platform_device *pdev)
1073 {
1074 	unsigned long flags;
1075 	struct dmtimer *timer;
1076 	struct device *dev = &pdev->dev;
1077 	const struct dmtimer_platform_data *pdata;
1078 	int ret;
1079 
1080 	pdata = of_device_get_match_data(dev);
1081 	if (!pdata)
1082 		pdata = dev_get_platdata(dev);
1083 	else
1084 		dev->platform_data = (void *)pdata;
1085 
1086 	if (!pdata) {
1087 		dev_err(dev, "%s: no platform data.\n", __func__);
1088 		return -ENODEV;
1089 	}
1090 
1091 	timer = devm_kzalloc(dev, sizeof(*timer), GFP_KERNEL);
1092 	if (!timer)
1093 		return  -ENOMEM;
1094 
1095 	timer->irq = platform_get_irq(pdev, 0);
1096 	if (timer->irq < 0)
1097 		return timer->irq;
1098 
1099 	timer->io_base = devm_platform_ioremap_resource(pdev, 0);
1100 	if (IS_ERR(timer->io_base))
1101 		return PTR_ERR(timer->io_base);
1102 
1103 	platform_set_drvdata(pdev, timer);
1104 
1105 	if (dev->of_node) {
1106 		if (of_property_read_bool(dev->of_node, "ti,timer-alwon"))
1107 			timer->capability |= OMAP_TIMER_ALWON;
1108 		if (of_property_read_bool(dev->of_node, "ti,timer-dsp"))
1109 			timer->capability |= OMAP_TIMER_HAS_DSP_IRQ;
1110 		if (of_property_read_bool(dev->of_node, "ti,timer-pwm"))
1111 			timer->capability |= OMAP_TIMER_HAS_PWM;
1112 		if (of_property_read_bool(dev->of_node, "ti,timer-secure"))
1113 			timer->capability |= OMAP_TIMER_SECURE;
1114 	} else {
1115 		timer->id = pdev->id;
1116 		timer->capability = pdata->timer_capability;
1117 		timer->reserved = omap_dm_timer_reserved_systimer(timer->id);
1118 	}
1119 
1120 	timer->omap1 = timer->capability & OMAP_TIMER_NEEDS_RESET;
1121 
1122 	/* OMAP1 devices do not yet use the clock framework for dmtimers */
1123 	if (!timer->omap1) {
1124 		timer->fclk = devm_clk_get(dev, "fck");
1125 		if (IS_ERR(timer->fclk))
1126 			return PTR_ERR(timer->fclk);
1127 	} else {
1128 		timer->fclk = ERR_PTR(-ENODEV);
1129 	}
1130 
1131 	if (!(timer->capability & OMAP_TIMER_ALWON)) {
1132 		timer->nb.notifier_call = omap_timer_context_notifier;
1133 		cpu_pm_register_notifier(&timer->nb);
1134 	}
1135 
1136 	timer->errata = pdata->timer_errata;
1137 
1138 	timer->pdev = pdev;
1139 
1140 	pm_runtime_enable(dev);
1141 
1142 	if (!timer->reserved) {
1143 		ret = pm_runtime_resume_and_get(dev);
1144 		if (ret) {
1145 			dev_err(dev, "%s: pm_runtime_get_sync failed!\n",
1146 				__func__);
1147 			goto err_disable;
1148 		}
1149 		__omap_dm_timer_init_regs(timer);
1150 
1151 		/* Clear timer configuration */
1152 		dmtimer_write(timer, OMAP_TIMER_CTRL_REG, 0);
1153 
1154 		pm_runtime_put(dev);
1155 	}
1156 
1157 	/* add the timer element to the list */
1158 	spin_lock_irqsave(&dm_timer_lock, flags);
1159 	list_add_tail(&timer->node, &omap_timer_list);
1160 	spin_unlock_irqrestore(&dm_timer_lock, flags);
1161 
1162 	dev_dbg(dev, "Device Probed.\n");
1163 
1164 	return 0;
1165 
1166 err_disable:
1167 	pm_runtime_disable(dev);
1168 	return ret;
1169 }
1170 
1171 /**
1172  * omap_dm_timer_remove - cleanup a registered timer device
1173  * @pdev:	pointer to current timer platform device
1174  *
1175  * Called by driver framework whenever a timer device is unregistered.
1176  * In addition to freeing platform resources it also deletes the timer
1177  * entry from the local list.
1178  */
1179 static void omap_dm_timer_remove(struct platform_device *pdev)
1180 {
1181 	struct dmtimer *timer;
1182 	unsigned long flags;
1183 	int ret = -EINVAL;
1184 
1185 	spin_lock_irqsave(&dm_timer_lock, flags);
1186 	list_for_each_entry(timer, &omap_timer_list, node)
1187 		if (!strcmp(dev_name(&timer->pdev->dev),
1188 			    dev_name(&pdev->dev))) {
1189 			if (!(timer->capability & OMAP_TIMER_ALWON))
1190 				cpu_pm_unregister_notifier(&timer->nb);
1191 			list_del(&timer->node);
1192 			ret = 0;
1193 			break;
1194 		}
1195 	spin_unlock_irqrestore(&dm_timer_lock, flags);
1196 
1197 	pm_runtime_disable(&pdev->dev);
1198 
1199 	if (ret)
1200 		dev_err(&pdev->dev, "Unable to determine timer entry in list of drivers on remove\n");
1201 }
1202 
1203 static const struct omap_dm_timer_ops dmtimer_ops = {
1204 	.request_by_node = omap_dm_timer_request_by_node,
1205 	.request_specific = omap_dm_timer_request_specific,
1206 	.request = omap_dm_timer_request,
1207 	.set_source = omap_dm_timer_set_source,
1208 	.get_irq = omap_dm_timer_get_irq,
1209 	.set_int_enable = omap_dm_timer_set_int_enable,
1210 	.set_int_disable = omap_dm_timer_set_int_disable,
1211 	.free = omap_dm_timer_free,
1212 	.enable = omap_dm_timer_enable,
1213 	.disable = omap_dm_timer_disable,
1214 	.get_fclk = omap_dm_timer_get_fclk,
1215 	.start = omap_dm_timer_start,
1216 	.stop = omap_dm_timer_stop,
1217 	.set_load = omap_dm_timer_set_load,
1218 	.set_match = omap_dm_timer_set_match,
1219 	.set_pwm = omap_dm_timer_set_pwm,
1220 	.get_pwm_status = omap_dm_timer_get_pwm_status,
1221 	.set_prescaler = omap_dm_timer_set_prescaler,
1222 	.read_counter = omap_dm_timer_read_counter,
1223 	.write_counter = omap_dm_timer_write_counter,
1224 	.read_status = omap_dm_timer_read_status,
1225 	.write_status = omap_dm_timer_write_status,
1226 };
1227 
1228 static const struct dmtimer_platform_data omap3plus_pdata = {
1229 	.timer_errata = OMAP_TIMER_ERRATA_I103_I767,
1230 	.timer_ops = &dmtimer_ops,
1231 };
1232 
1233 static const struct dmtimer_platform_data am6_pdata = {
1234 	.timer_ops = &dmtimer_ops,
1235 };
1236 
1237 static const struct of_device_id omap_timer_match[] = {
1238 	{
1239 		.compatible = "ti,omap2420-timer",
1240 	},
1241 	{
1242 		.compatible = "ti,omap3430-timer",
1243 		.data = &omap3plus_pdata,
1244 	},
1245 	{
1246 		.compatible = "ti,omap4430-timer",
1247 		.data = &omap3plus_pdata,
1248 	},
1249 	{
1250 		.compatible = "ti,omap5430-timer",
1251 		.data = &omap3plus_pdata,
1252 	},
1253 	{
1254 		.compatible = "ti,am335x-timer",
1255 		.data = &omap3plus_pdata,
1256 	},
1257 	{
1258 		.compatible = "ti,am335x-timer-1ms",
1259 		.data = &omap3plus_pdata,
1260 	},
1261 	{
1262 		.compatible = "ti,dm816-timer",
1263 		.data = &omap3plus_pdata,
1264 	},
1265 	{
1266 		.compatible = "ti,am654-timer",
1267 		.data = &am6_pdata,
1268 	},
1269 	{},
1270 };
1271 MODULE_DEVICE_TABLE(of, omap_timer_match);
1272 
1273 static struct platform_driver omap_dm_timer_driver = {
1274 	.probe  = omap_dm_timer_probe,
1275 	.remove_new = omap_dm_timer_remove,
1276 	.driver = {
1277 		.name   = "omap_timer",
1278 		.of_match_table = omap_timer_match,
1279 		.pm = &omap_dm_timer_pm_ops,
1280 	},
1281 };
1282 
1283 module_platform_driver(omap_dm_timer_driver);
1284 
1285 MODULE_DESCRIPTION("OMAP Dual-Mode Timer Driver");
1286 MODULE_AUTHOR("Texas Instruments Inc");
1287