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v5.4
  1/*
  2 * linux/arch/arm/mach-omap2/timer.c
  3 *
  4 * OMAP2 GP timer support.
  5 *
  6 * Copyright (C) 2009 Nokia Corporation
  7 *
  8 * Update to use new clocksource/clockevent layers
  9 * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
 10 * Copyright (C) 2007 MontaVista Software, Inc.
 11 *
 12 * Original driver:
 13 * Copyright (C) 2005 Nokia Corporation
 14 * Author: Paul Mundt <paul.mundt@nokia.com>
 15 *         Juha Yrjölä <juha.yrjola@nokia.com>
 16 * OMAP Dual-mode timer framework support by Timo Teras
 17 *
 18 * Some parts based off of TI's 24xx code:
 19 *
 20 * Copyright (C) 2004-2009 Texas Instruments, Inc.
 21 *
 22 * Roughly modelled after the OMAP1 MPU timer code.
 23 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
 24 *
 25 * This file is subject to the terms and conditions of the GNU General Public
 26 * License. See the file "COPYING" in the main directory of this archive
 27 * for more details.
 28 */
 29#include <linux/init.h>
 30#include <linux/time.h>
 31#include <linux/interrupt.h>
 32#include <linux/err.h>
 33#include <linux/clk.h>
 34#include <linux/delay.h>
 35#include <linux/irq.h>
 36#include <linux/clocksource.h>
 37#include <linux/clockchips.h>
 38#include <linux/slab.h>
 39#include <linux/of.h>
 40#include <linux/of_address.h>
 41#include <linux/of_irq.h>
 42#include <linux/platform_device.h>
 43#include <linux/platform_data/dmtimer-omap.h>
 44#include <linux/sched_clock.h>
 45
 46#include <asm/mach/time.h>
 
 47
 48#include "omap_hwmod.h"
 49#include "omap_device.h"
 50#include <plat/counter-32k.h>
 51#include <clocksource/timer-ti-dm.h>
 
 52
 53#include "soc.h"
 54#include "common.h"
 55#include "control.h"
 56#include "powerdomain.h"
 57#include "omap-secure.h"
 58
 59#define REALTIME_COUNTER_BASE				0x48243200
 60#define INCREMENTER_NUMERATOR_OFFSET			0x10
 61#define INCREMENTER_DENUMERATOR_RELOAD_OFFSET		0x14
 62#define NUMERATOR_DENUMERATOR_MASK			0xfffff000
 63
 64/* Clockevent code */
 65
 66static struct omap_dm_timer clkev;
 67static struct clock_event_device clockevent_gpt;
 68
 69/* Clockevent hwmod for am335x and am437x suspend */
 70static struct omap_hwmod *clockevent_gpt_hwmod;
 71
 72/* Clockesource hwmod for am437x suspend */
 73static struct omap_hwmod *clocksource_gpt_hwmod;
 74
 75#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
 76static unsigned long arch_timer_freq;
 77
 78void set_cntfreq(void)
 79{
 80	omap_smc1(OMAP5_DRA7_MON_SET_CNTFRQ_INDEX, arch_timer_freq);
 81}
 82#endif
 83
 84static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
 85{
 86	struct clock_event_device *evt = &clockevent_gpt;
 87
 88	__omap_dm_timer_write_status(&clkev, OMAP_TIMER_INT_OVERFLOW);
 89
 90	evt->event_handler(evt);
 91	return IRQ_HANDLED;
 92}
 93
 94static struct irqaction omap2_gp_timer_irq = {
 95	.name		= "gp_timer",
 96	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
 97	.handler	= omap2_gp_timer_interrupt,
 98};
 99
100static int omap2_gp_timer_set_next_event(unsigned long cycles,
101					 struct clock_event_device *evt)
102{
103	__omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_ST,
104				   0xffffffff - cycles, OMAP_TIMER_POSTED);
105
106	return 0;
107}
108
109static int omap2_gp_timer_shutdown(struct clock_event_device *evt)
110{
111	__omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
112	return 0;
113}
114
115static int omap2_gp_timer_set_periodic(struct clock_event_device *evt)
116{
117	u32 period;
118
119	__omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
120
121	period = clkev.rate / HZ;
122	period -= 1;
123	/* Looks like we need to first set the load value separately */
124	__omap_dm_timer_write(&clkev, OMAP_TIMER_LOAD_REG, 0xffffffff - period,
125			      OMAP_TIMER_POSTED);
126	__omap_dm_timer_load_start(&clkev,
127				   OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
128				   0xffffffff - period, OMAP_TIMER_POSTED);
129	return 0;
130}
131
132static void omap_clkevt_idle(struct clock_event_device *unused)
133{
134	if (!clockevent_gpt_hwmod)
135		return;
136
137	omap_hwmod_idle(clockevent_gpt_hwmod);
138}
139
140static void omap_clkevt_unidle(struct clock_event_device *unused)
141{
142	if (!clockevent_gpt_hwmod)
143		return;
144
145	omap_hwmod_enable(clockevent_gpt_hwmod);
146	__omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
147}
148
149static struct clock_event_device clockevent_gpt = {
150	.features		= CLOCK_EVT_FEAT_PERIODIC |
151				  CLOCK_EVT_FEAT_ONESHOT,
152	.rating			= 300,
153	.set_next_event		= omap2_gp_timer_set_next_event,
154	.set_state_shutdown	= omap2_gp_timer_shutdown,
155	.set_state_periodic	= omap2_gp_timer_set_periodic,
156	.set_state_oneshot	= omap2_gp_timer_shutdown,
157	.tick_resume		= omap2_gp_timer_shutdown,
158};
159
 
 
 
 
 
 
160static const struct of_device_id omap_timer_match[] __initconst = {
161	{ .compatible = "ti,omap2420-timer", },
162	{ .compatible = "ti,omap3430-timer", },
163	{ .compatible = "ti,omap4430-timer", },
164	{ .compatible = "ti,omap5430-timer", },
165	{ .compatible = "ti,dm814-timer", },
166	{ .compatible = "ti,dm816-timer", },
167	{ .compatible = "ti,am335x-timer", },
168	{ .compatible = "ti,am335x-timer-1ms", },
169	{ }
170};
171
172static int omap_timer_add_disabled_property(struct device_node *np)
173{
174	struct property *prop;
175
176	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
177	if (!prop)
178		return -ENOMEM;
179
180	prop->name = "status";
181	prop->value = "disabled";
182	prop->length = strlen(prop->value);
183
184	return of_add_property(np, prop);
185}
186
187static int omap_timer_update_dt(struct device_node *np)
188{
189	int error = 0;
190
191	if (!of_device_is_compatible(np, "ti,omap-counter32k")) {
192		error = omap_timer_add_disabled_property(np);
193		if (error)
194			return error;
195	}
196
197	/* No parent interconnect target module configured? */
198	if (of_get_property(np, "ti,hwmods", NULL))
199		return error;
200
201	/* Tag parent interconnect target module disabled */
202	error = omap_timer_add_disabled_property(np->parent);
203	if (error)
204		return error;
205
206	return 0;
207}
208
209/**
210 * omap_get_timer_dt - get a timer using device-tree
211 * @match	- device-tree match structure for matching a device type
212 * @property	- optional timer property to match
213 *
214 * Helper function to get a timer during early boot using device-tree for use
215 * as kernel system timer. Optionally, the property argument can be used to
216 * select a timer with a specific property. Once a timer is found then mark
217 * the timer node in device-tree as disabled, to prevent the kernel from
218 * registering this timer as a platform device and so no one else can use it.
219 */
220static struct device_node * __init omap_get_timer_dt(const struct of_device_id *match,
221						     const char *property)
222{
223	struct device_node *np;
224	int error;
225
226	for_each_matching_node(np, match) {
227		if (!of_device_is_available(np))
228			continue;
229
230		if (property && !of_get_property(np, property, NULL))
231			continue;
232
233		if (!property && (of_get_property(np, "ti,timer-alwon", NULL) ||
234				  of_get_property(np, "ti,timer-dsp", NULL) ||
235				  of_get_property(np, "ti,timer-pwm", NULL) ||
236				  of_get_property(np, "ti,timer-secure", NULL)))
237			continue;
238
239		error = omap_timer_update_dt(np);
240		WARN(error, "%s: Could not update dt: %i\n", __func__, error);
241
242		return np;
243	}
244
245	return NULL;
246}
247
248/**
249 * omap_dmtimer_init - initialisation function when device tree is used
250 *
251 * For secure OMAP3/DRA7xx devices, timers with device type "timer-secure"
252 * cannot be used by the kernel as they are reserved. Therefore, to prevent the
253 * kernel registering these devices remove them dynamically from the device
254 * tree on boot.
255 */
256static void __init omap_dmtimer_init(void)
257{
258	struct device_node *np;
259
260	if (!cpu_is_omap34xx() && !soc_is_dra7xx())
261		return;
262
263	/* If we are a secure device, remove any secure timer nodes */
264	if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
265		np = omap_get_timer_dt(omap_timer_match, "ti,timer-secure");
266		of_node_put(np);
267	}
268}
269
270/**
271 * omap_dm_timer_get_errata - get errata flags for a timer
272 *
273 * Get the timer errata flags that are specific to the OMAP device being used.
274 */
275static u32 __init omap_dm_timer_get_errata(void)
276{
277	if (cpu_is_omap24xx())
278		return 0;
279
280	return OMAP_TIMER_ERRATA_I103_I767;
281}
282
283static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
284					 const char *fck_source,
285					 const char *property,
286					 const char **timer_name,
287					 int posted)
288{
 
289	const char *oh_name = NULL;
290	struct device_node *np;
291	struct omap_hwmod *oh;
 
292	struct clk *src;
293	int r = 0;
294
295	np = omap_get_timer_dt(omap_timer_match, property);
296	if (!np)
297		return -ENODEV;
 
298
299	of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
300	if (!oh_name) {
301		of_property_read_string_index(np->parent, "ti,hwmods", 0,
302					      &oh_name);
303		if (!oh_name)
304			return -ENODEV;
305	}
306
307	timer->irq = irq_of_parse_and_map(np, 0);
308	if (!timer->irq)
309		return -ENXIO;
310
311	timer->io_base = of_iomap(np, 0);
312
313	timer->fclk = of_clk_get_by_name(np, "fck");
 
 
 
314
315	of_node_put(np);
 
 
316
317	oh = omap_hwmod_lookup(oh_name);
318	if (!oh)
319		return -ENODEV;
320
321	*timer_name = oh->name;
322
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
323	if (!timer->io_base)
324		return -ENXIO;
325
326	omap_hwmod_setup_one(oh_name);
327
328	/* After the dmtimer is using hwmod these clocks won't be needed */
329	if (IS_ERR_OR_NULL(timer->fclk))
330		timer->fclk = clk_get(NULL, omap_hwmod_get_main_clk(oh));
331	if (IS_ERR(timer->fclk))
332		return PTR_ERR(timer->fclk);
333
334	src = clk_get(NULL, fck_source);
335	if (IS_ERR(src))
336		return PTR_ERR(src);
337
338	WARN(clk_set_parent(timer->fclk, src) < 0,
339	     "Cannot set timer parent clock, no PLL clock driver?");
340
341	clk_put(src);
342
343	omap_hwmod_enable(oh);
344	__omap_dm_timer_init_regs(timer);
345
346	if (posted)
347		__omap_dm_timer_enable_posted(timer);
348
349	/* Check that the intended posted configuration matches the actual */
350	if (posted != timer->posted)
351		return -EINVAL;
352
353	timer->rate = clk_get_rate(timer->fclk);
354	timer->reserved = 1;
355
356	return r;
357}
358
359#if !defined(CONFIG_SMP) && defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)
360void tick_broadcast(const struct cpumask *mask)
361{
362}
363#endif
364
365static void __init omap2_gp_clockevent_init(int gptimer_id,
366						const char *fck_source,
367						const char *property)
368{
369	int res;
370
371	clkev.id = gptimer_id;
372	clkev.errata = omap_dm_timer_get_errata();
373
374	/*
375	 * For clock-event timers we never read the timer counter and
376	 * so we are not impacted by errata i103 and i767. Therefore,
377	 * we can safely ignore this errata for clock-event timers.
378	 */
379	__omap_dm_timer_override_errata(&clkev, OMAP_TIMER_ERRATA_I103_I767);
380
381	res = omap_dm_timer_init_one(&clkev, fck_source, property,
382				     &clockevent_gpt.name, OMAP_TIMER_POSTED);
383	BUG_ON(res);
384
385	omap2_gp_timer_irq.dev_id = &clkev;
386	setup_irq(clkev.irq, &omap2_gp_timer_irq);
387
388	__omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
389
390	clockevent_gpt.cpumask = cpu_possible_mask;
391	clockevent_gpt.irq = omap_dm_timer_get_irq(&clkev);
392	clockevents_config_and_register(&clockevent_gpt, clkev.rate,
393					3, /* Timer internal resynch latency */
394					0xffffffff);
395
396	if (soc_is_am33xx() || soc_is_am43xx()) {
397		clockevent_gpt.suspend = omap_clkevt_idle;
398		clockevent_gpt.resume = omap_clkevt_unidle;
399
400		clockevent_gpt_hwmod =
401			omap_hwmod_lookup(clockevent_gpt.name);
402	}
403
404	pr_info("OMAP clockevent source: %s at %lu Hz\n", clockevent_gpt.name,
405		clkev.rate);
406}
407
408/* Clocksource code */
409static struct omap_dm_timer clksrc;
410static bool use_gptimer_clksrc __initdata;
411
412/*
413 * clocksource
414 */
415static u64 clocksource_read_cycles(struct clocksource *cs)
416{
417	return (u64)__omap_dm_timer_read_counter(&clksrc,
418						     OMAP_TIMER_NONPOSTED);
419}
420
421static struct clocksource clocksource_gpt = {
422	.rating		= 300,
423	.read		= clocksource_read_cycles,
424	.mask		= CLOCKSOURCE_MASK(32),
425	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
426};
427
428static u64 notrace dmtimer_read_sched_clock(void)
429{
430	if (clksrc.reserved)
431		return __omap_dm_timer_read_counter(&clksrc,
432						    OMAP_TIMER_NONPOSTED);
433
434	return 0;
435}
436
437static const struct of_device_id omap_counter_match[] __initconst = {
438	{ .compatible = "ti,omap-counter32k", },
439	{ }
440};
441
442/* Setup free-running counter for clocksource */
443static int __init __maybe_unused omap2_sync32k_clocksource_init(void)
444{
445	int ret;
446	struct device_node *np = NULL;
447	struct omap_hwmod *oh;
448	const char *oh_name = "counter_32k";
449
450	/*
451	 * See if the 32kHz counter is supported.
 
452	 */
453	np = omap_get_timer_dt(omap_counter_match, NULL);
454	if (!np)
455		return -ENODEV;
 
456
457	of_property_read_string_index(np->parent, "ti,hwmods", 0, &oh_name);
458	if (!oh_name) {
459		of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
460		if (!oh_name)
461			return -ENODEV;
462	}
463
464	/*
465	 * First check hwmod data is available for sync32k counter
466	 */
467	oh = omap_hwmod_lookup(oh_name);
468	if (!oh || oh->slaves_cnt == 0)
469		return -ENODEV;
470
471	omap_hwmod_setup_one(oh_name);
472
473	ret = omap_hwmod_enable(oh);
474	if (ret) {
475		pr_warn("%s: failed to enable counter_32k module (%d)\n",
476							__func__, ret);
477		return ret;
478	}
479
480	return ret;
481}
482
483static unsigned int omap2_gptimer_clksrc_load;
484
485static void omap2_gptimer_clksrc_suspend(struct clocksource *unused)
486{
487	omap2_gptimer_clksrc_load =
488		__omap_dm_timer_read_counter(&clksrc, OMAP_TIMER_NONPOSTED);
489
490	omap_hwmod_idle(clocksource_gpt_hwmod);
491}
492
493static void omap2_gptimer_clksrc_resume(struct clocksource *unused)
494{
495	omap_hwmod_enable(clocksource_gpt_hwmod);
496
497	__omap_dm_timer_load_start(&clksrc,
498				   OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR,
499				   omap2_gptimer_clksrc_load,
500				   OMAP_TIMER_NONPOSTED);
501}
502
503static void __init omap2_gptimer_clocksource_init(int gptimer_id,
504						  const char *fck_source,
505						  const char *property)
506{
507	int res;
508
509	clksrc.id = gptimer_id;
510	clksrc.errata = omap_dm_timer_get_errata();
511
512	res = omap_dm_timer_init_one(&clksrc, fck_source, property,
513				     &clocksource_gpt.name,
514				     OMAP_TIMER_NONPOSTED);
515
516	if (soc_is_am43xx()) {
517		clocksource_gpt.suspend = omap2_gptimer_clksrc_suspend;
518		clocksource_gpt.resume = omap2_gptimer_clksrc_resume;
519
520		clocksource_gpt_hwmod =
521			omap_hwmod_lookup(clocksource_gpt.name);
522	}
523
524	BUG_ON(res);
525
526	__omap_dm_timer_load_start(&clksrc,
527				   OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0,
528				   OMAP_TIMER_NONPOSTED);
529	sched_clock_register(dmtimer_read_sched_clock, 32, clksrc.rate);
530
531	if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
532		pr_err("Could not register clocksource %s\n",
533			clocksource_gpt.name);
534	else
535		pr_info("OMAP clocksource: %s at %lu Hz\n",
536			clocksource_gpt.name, clksrc.rate);
537}
538
539static void __init __omap_sync32k_timer_init(int clkev_nr, const char *clkev_src,
540		const char *clkev_prop, int clksrc_nr, const char *clksrc_src,
541		const char *clksrc_prop, bool gptimer)
542{
543	omap_clk_init();
544	omap_dmtimer_init();
545	omap2_gp_clockevent_init(clkev_nr, clkev_src, clkev_prop);
546
547	/* Enable the use of clocksource="gp_timer" kernel parameter */
548	if (use_gptimer_clksrc || gptimer)
549		omap2_gptimer_clocksource_init(clksrc_nr, clksrc_src,
550						clksrc_prop);
551	else
552		omap2_sync32k_clocksource_init();
553}
554
555void __init omap_init_time(void)
556{
557	__omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
558			2, "timer_sys_ck", NULL, false);
559
560	timer_probe();
561}
562
563#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM43XX)
564void __init omap3_secure_sync32k_timer_init(void)
565{
566	__omap_sync32k_timer_init(12, "secure_32k_fck", "ti,timer-secure",
567			2, "timer_sys_ck", NULL, false);
568
569	timer_probe();
570}
571#endif /* CONFIG_ARCH_OMAP3 */
572
573#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX) || \
574	defined(CONFIG_SOC_AM43XX)
575void __init omap3_gptimer_timer_init(void)
576{
577	__omap_sync32k_timer_init(2, "timer_sys_ck", NULL,
578			1, "timer_sys_ck", "ti,timer-alwon", true);
579	if (of_have_populated_dt())
580		timer_probe();
581}
582#endif
583
584#if defined(CONFIG_ARCH_OMAP4) || defined(CONFIG_SOC_OMAP5) ||		\
585	defined(CONFIG_SOC_DRA7XX)
586static void __init omap4_sync32k_timer_init(void)
587{
588	__omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
589			2, "sys_clkin_ck", NULL, false);
590}
591
592void __init omap4_local_timer_init(void)
593{
594	omap4_sync32k_timer_init();
595	timer_probe();
596}
597#endif
598
599#if defined(CONFIG_SOC_OMAP5) || defined(CONFIG_SOC_DRA7XX)
600
601/*
602 * The realtime counter also called master counter, is a free-running
603 * counter, which is related to real time. It produces the count used
604 * by the CPU local timer peripherals in the MPU cluster. The timer counts
605 * at a rate of 6.144 MHz. Because the device operates on different clocks
606 * in different power modes, the master counter shifts operation between
607 * clocks, adjusting the increment per clock in hardware accordingly to
608 * maintain a constant count rate.
609 */
610static void __init realtime_counter_init(void)
611{
612#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
613	void __iomem *base;
614	static struct clk *sys_clk;
615	unsigned long rate;
616	unsigned int reg;
617	unsigned long long num, den;
618
619	base = ioremap(REALTIME_COUNTER_BASE, SZ_32);
620	if (!base) {
621		pr_err("%s: ioremap failed\n", __func__);
622		return;
623	}
624	sys_clk = clk_get(NULL, "sys_clkin");
625	if (IS_ERR(sys_clk)) {
626		pr_err("%s: failed to get system clock handle\n", __func__);
627		iounmap(base);
628		return;
629	}
630
631	rate = clk_get_rate(sys_clk);
632
633	if (soc_is_dra7xx()) {
634		/*
635		 * Errata i856 says the 32.768KHz crystal does not start at
636		 * power on, so the CPU falls back to an emulated 32KHz clock
637		 * based on sysclk / 610 instead. This causes the master counter
638		 * frequency to not be 6.144MHz but at sysclk / 610 * 375 / 2
639		 * (OR sysclk * 75 / 244)
640		 *
641		 * This affects at least the DRA7/AM572x 1.0, 1.1 revisions.
642		 * Of course any board built without a populated 32.768KHz
643		 * crystal would also need this fix even if the CPU is fixed
644		 * later.
645		 *
646		 * Either case can be detected by using the two speedselect bits
647		 * If they are not 0, then the 32.768KHz clock driving the
648		 * coarse counter that corrects the fine counter every time it
649		 * ticks is actually rate/610 rather than 32.768KHz and we
650		 * should compensate to avoid the 570ppm (at 20MHz, much worse
651		 * at other rates) too fast system time.
652		 */
653		reg = omap_ctrl_readl(DRA7_CTRL_CORE_BOOTSTRAP);
654		if (reg & DRA7_SPEEDSELECT_MASK) {
655			num = 75;
656			den = 244;
657			goto sysclk1_based;
658		}
659	}
660
661	/* Numerator/denumerator values refer TRM Realtime Counter section */
662	switch (rate) {
663	case 12000000:
664		num = 64;
665		den = 125;
666		break;
667	case 13000000:
668		num = 768;
669		den = 1625;
670		break;
671	case 19200000:
672		num = 8;
673		den = 25;
674		break;
675	case 20000000:
676		num = 192;
677		den = 625;
678		break;
679	case 26000000:
680		num = 384;
681		den = 1625;
682		break;
683	case 27000000:
684		num = 256;
685		den = 1125;
686		break;
687	case 38400000:
688	default:
689		/* Program it for 38.4 MHz */
690		num = 4;
691		den = 25;
692		break;
693	}
694
695sysclk1_based:
696	/* Program numerator and denumerator registers */
697	reg = readl_relaxed(base + INCREMENTER_NUMERATOR_OFFSET) &
698			NUMERATOR_DENUMERATOR_MASK;
699	reg |= num;
700	writel_relaxed(reg, base + INCREMENTER_NUMERATOR_OFFSET);
701
702	reg = readl_relaxed(base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET) &
703			NUMERATOR_DENUMERATOR_MASK;
704	reg |= den;
705	writel_relaxed(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET);
706
707	arch_timer_freq = DIV_ROUND_UP_ULL(rate * num, den);
708	set_cntfreq();
709
710	iounmap(base);
711#endif
712}
713
714void __init omap5_realtime_timer_init(void)
715{
716	omap4_sync32k_timer_init();
717	realtime_counter_init();
718
719	timer_probe();
720}
721#endif /* CONFIG_SOC_OMAP5 || CONFIG_SOC_DRA7XX */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
722
723/**
724 * omap2_override_clocksource - clocksource override with user configuration
725 *
726 * Allows user to override default clocksource, using kernel parameter
727 *   clocksource="gp_timer"	(For all OMAP2PLUS architectures)
728 *
729 * Note that, here we are using same standard kernel parameter "clocksource=",
730 * and not introducing any OMAP specific interface.
731 */
732static int __init omap2_override_clocksource(char *str)
733{
734	if (!str)
735		return 0;
736	/*
737	 * For OMAP architecture, we only have two options
738	 *    - sync_32k (default)
739	 *    - gp_timer (sys_clk based)
740	 */
741	if (!strcmp(str, "gp_timer"))
742		use_gptimer_clksrc = true;
743
744	return 0;
745}
746early_param("clocksource", omap2_override_clocksource);
v4.10.11
  1/*
  2 * linux/arch/arm/mach-omap2/timer.c
  3 *
  4 * OMAP2 GP timer support.
  5 *
  6 * Copyright (C) 2009 Nokia Corporation
  7 *
  8 * Update to use new clocksource/clockevent layers
  9 * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
 10 * Copyright (C) 2007 MontaVista Software, Inc.
 11 *
 12 * Original driver:
 13 * Copyright (C) 2005 Nokia Corporation
 14 * Author: Paul Mundt <paul.mundt@nokia.com>
 15 *         Juha Yrjölä <juha.yrjola@nokia.com>
 16 * OMAP Dual-mode timer framework support by Timo Teras
 17 *
 18 * Some parts based off of TI's 24xx code:
 19 *
 20 * Copyright (C) 2004-2009 Texas Instruments, Inc.
 21 *
 22 * Roughly modelled after the OMAP1 MPU timer code.
 23 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
 24 *
 25 * This file is subject to the terms and conditions of the GNU General Public
 26 * License. See the file "COPYING" in the main directory of this archive
 27 * for more details.
 28 */
 29#include <linux/init.h>
 30#include <linux/time.h>
 31#include <linux/interrupt.h>
 32#include <linux/err.h>
 33#include <linux/clk.h>
 34#include <linux/delay.h>
 35#include <linux/irq.h>
 36#include <linux/clocksource.h>
 37#include <linux/clockchips.h>
 38#include <linux/slab.h>
 39#include <linux/of.h>
 40#include <linux/of_address.h>
 41#include <linux/of_irq.h>
 42#include <linux/platform_device.h>
 43#include <linux/platform_data/dmtimer-omap.h>
 44#include <linux/sched_clock.h>
 45
 46#include <asm/mach/time.h>
 47#include <asm/smp_twd.h>
 48
 49#include "omap_hwmod.h"
 50#include "omap_device.h"
 51#include <plat/counter-32k.h>
 52#include <plat/dmtimer.h>
 53#include "omap-pm.h"
 54
 55#include "soc.h"
 56#include "common.h"
 57#include "control.h"
 58#include "powerdomain.h"
 59#include "omap-secure.h"
 60
 61#define REALTIME_COUNTER_BASE				0x48243200
 62#define INCREMENTER_NUMERATOR_OFFSET			0x10
 63#define INCREMENTER_DENUMERATOR_RELOAD_OFFSET		0x14
 64#define NUMERATOR_DENUMERATOR_MASK			0xfffff000
 65
 66/* Clockevent code */
 67
 68static struct omap_dm_timer clkev;
 69static struct clock_event_device clockevent_gpt;
 70
 
 
 
 
 
 
 71#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
 72static unsigned long arch_timer_freq;
 73
 74void set_cntfreq(void)
 75{
 76	omap_smc1(OMAP5_DRA7_MON_SET_CNTFRQ_INDEX, arch_timer_freq);
 77}
 78#endif
 79
 80static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
 81{
 82	struct clock_event_device *evt = &clockevent_gpt;
 83
 84	__omap_dm_timer_write_status(&clkev, OMAP_TIMER_INT_OVERFLOW);
 85
 86	evt->event_handler(evt);
 87	return IRQ_HANDLED;
 88}
 89
 90static struct irqaction omap2_gp_timer_irq = {
 91	.name		= "gp_timer",
 92	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
 93	.handler	= omap2_gp_timer_interrupt,
 94};
 95
 96static int omap2_gp_timer_set_next_event(unsigned long cycles,
 97					 struct clock_event_device *evt)
 98{
 99	__omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_ST,
100				   0xffffffff - cycles, OMAP_TIMER_POSTED);
101
102	return 0;
103}
104
105static int omap2_gp_timer_shutdown(struct clock_event_device *evt)
106{
107	__omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
108	return 0;
109}
110
111static int omap2_gp_timer_set_periodic(struct clock_event_device *evt)
112{
113	u32 period;
114
115	__omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
116
117	period = clkev.rate / HZ;
118	period -= 1;
119	/* Looks like we need to first set the load value separately */
120	__omap_dm_timer_write(&clkev, OMAP_TIMER_LOAD_REG, 0xffffffff - period,
121			      OMAP_TIMER_POSTED);
122	__omap_dm_timer_load_start(&clkev,
123				   OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
124				   0xffffffff - period, OMAP_TIMER_POSTED);
125	return 0;
126}
127
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
128static struct clock_event_device clockevent_gpt = {
129	.features		= CLOCK_EVT_FEAT_PERIODIC |
130				  CLOCK_EVT_FEAT_ONESHOT,
131	.rating			= 300,
132	.set_next_event		= omap2_gp_timer_set_next_event,
133	.set_state_shutdown	= omap2_gp_timer_shutdown,
134	.set_state_periodic	= omap2_gp_timer_set_periodic,
135	.set_state_oneshot	= omap2_gp_timer_shutdown,
136	.tick_resume		= omap2_gp_timer_shutdown,
137};
138
139static struct property device_disabled = {
140	.name = "status",
141	.length = sizeof("disabled"),
142	.value = "disabled",
143};
144
145static const struct of_device_id omap_timer_match[] __initconst = {
146	{ .compatible = "ti,omap2420-timer", },
147	{ .compatible = "ti,omap3430-timer", },
148	{ .compatible = "ti,omap4430-timer", },
149	{ .compatible = "ti,omap5430-timer", },
150	{ .compatible = "ti,dm814-timer", },
151	{ .compatible = "ti,dm816-timer", },
152	{ .compatible = "ti,am335x-timer", },
153	{ .compatible = "ti,am335x-timer-1ms", },
154	{ }
155};
156
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
157/**
158 * omap_get_timer_dt - get a timer using device-tree
159 * @match	- device-tree match structure for matching a device type
160 * @property	- optional timer property to match
161 *
162 * Helper function to get a timer during early boot using device-tree for use
163 * as kernel system timer. Optionally, the property argument can be used to
164 * select a timer with a specific property. Once a timer is found then mark
165 * the timer node in device-tree as disabled, to prevent the kernel from
166 * registering this timer as a platform device and so no one else can use it.
167 */
168static struct device_node * __init omap_get_timer_dt(const struct of_device_id *match,
169						     const char *property)
170{
171	struct device_node *np;
 
172
173	for_each_matching_node(np, match) {
174		if (!of_device_is_available(np))
175			continue;
176
177		if (property && !of_get_property(np, property, NULL))
178			continue;
179
180		if (!property && (of_get_property(np, "ti,timer-alwon", NULL) ||
181				  of_get_property(np, "ti,timer-dsp", NULL) ||
182				  of_get_property(np, "ti,timer-pwm", NULL) ||
183				  of_get_property(np, "ti,timer-secure", NULL)))
184			continue;
185
186		if (!of_device_is_compatible(np, "ti,omap-counter32k"))
187			of_add_property(np, &device_disabled);
 
188		return np;
189	}
190
191	return NULL;
192}
193
194/**
195 * omap_dmtimer_init - initialisation function when device tree is used
196 *
197 * For secure OMAP3/DRA7xx devices, timers with device type "timer-secure"
198 * cannot be used by the kernel as they are reserved. Therefore, to prevent the
199 * kernel registering these devices remove them dynamically from the device
200 * tree on boot.
201 */
202static void __init omap_dmtimer_init(void)
203{
204	struct device_node *np;
205
206	if (!cpu_is_omap34xx() && !soc_is_dra7xx())
207		return;
208
209	/* If we are a secure device, remove any secure timer nodes */
210	if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
211		np = omap_get_timer_dt(omap_timer_match, "ti,timer-secure");
212		of_node_put(np);
213	}
214}
215
216/**
217 * omap_dm_timer_get_errata - get errata flags for a timer
218 *
219 * Get the timer errata flags that are specific to the OMAP device being used.
220 */
221static u32 __init omap_dm_timer_get_errata(void)
222{
223	if (cpu_is_omap24xx())
224		return 0;
225
226	return OMAP_TIMER_ERRATA_I103_I767;
227}
228
229static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
230					 const char *fck_source,
231					 const char *property,
232					 const char **timer_name,
233					 int posted)
234{
235	char name[10]; /* 10 = sizeof("gptXX_Xck0") */
236	const char *oh_name = NULL;
237	struct device_node *np;
238	struct omap_hwmod *oh;
239	struct resource irq, mem;
240	struct clk *src;
241	int r = 0;
242
243	if (of_have_populated_dt()) {
244		np = omap_get_timer_dt(omap_timer_match, property);
245		if (!np)
246			return -ENODEV;
247
248		of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
 
 
 
249		if (!oh_name)
250			return -ENODEV;
 
251
252		timer->irq = irq_of_parse_and_map(np, 0);
253		if (!timer->irq)
254			return -ENXIO;
255
256		timer->io_base = of_iomap(np, 0);
257
258		of_node_put(np);
259	} else {
260		if (omap_dm_timer_reserve_systimer(timer->id))
261			return -ENODEV;
262
263		sprintf(name, "timer%d", timer->id);
264		oh_name = name;
265	}
266
267	oh = omap_hwmod_lookup(oh_name);
268	if (!oh)
269		return -ENODEV;
270
271	*timer_name = oh->name;
272
273	if (!of_have_populated_dt()) {
274		r = omap_hwmod_get_resource_byname(oh, IORESOURCE_IRQ, NULL,
275						   &irq);
276		if (r)
277			return -ENXIO;
278		timer->irq = irq.start;
279
280		r = omap_hwmod_get_resource_byname(oh, IORESOURCE_MEM, NULL,
281						   &mem);
282		if (r)
283			return -ENXIO;
284
285		/* Static mapping, never released */
286		timer->io_base = ioremap(mem.start, mem.end - mem.start);
287	}
288
289	if (!timer->io_base)
290		return -ENXIO;
291
292	omap_hwmod_setup_one(oh_name);
293
294	/* After the dmtimer is using hwmod these clocks won't be needed */
295	timer->fclk = clk_get(NULL, omap_hwmod_get_main_clk(oh));
 
296	if (IS_ERR(timer->fclk))
297		return PTR_ERR(timer->fclk);
298
299	src = clk_get(NULL, fck_source);
300	if (IS_ERR(src))
301		return PTR_ERR(src);
302
303	WARN(clk_set_parent(timer->fclk, src) < 0,
304	     "Cannot set timer parent clock, no PLL clock driver?");
305
306	clk_put(src);
307
308	omap_hwmod_enable(oh);
309	__omap_dm_timer_init_regs(timer);
310
311	if (posted)
312		__omap_dm_timer_enable_posted(timer);
313
314	/* Check that the intended posted configuration matches the actual */
315	if (posted != timer->posted)
316		return -EINVAL;
317
318	timer->rate = clk_get_rate(timer->fclk);
319	timer->reserved = 1;
320
321	return r;
322}
323
324#if !defined(CONFIG_SMP) && defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)
325void tick_broadcast(const struct cpumask *mask)
326{
327}
328#endif
329
330static void __init omap2_gp_clockevent_init(int gptimer_id,
331						const char *fck_source,
332						const char *property)
333{
334	int res;
335
336	clkev.id = gptimer_id;
337	clkev.errata = omap_dm_timer_get_errata();
338
339	/*
340	 * For clock-event timers we never read the timer counter and
341	 * so we are not impacted by errata i103 and i767. Therefore,
342	 * we can safely ignore this errata for clock-event timers.
343	 */
344	__omap_dm_timer_override_errata(&clkev, OMAP_TIMER_ERRATA_I103_I767);
345
346	res = omap_dm_timer_init_one(&clkev, fck_source, property,
347				     &clockevent_gpt.name, OMAP_TIMER_POSTED);
348	BUG_ON(res);
349
350	omap2_gp_timer_irq.dev_id = &clkev;
351	setup_irq(clkev.irq, &omap2_gp_timer_irq);
352
353	__omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
354
355	clockevent_gpt.cpumask = cpu_possible_mask;
356	clockevent_gpt.irq = omap_dm_timer_get_irq(&clkev);
357	clockevents_config_and_register(&clockevent_gpt, clkev.rate,
358					3, /* Timer internal resynch latency */
359					0xffffffff);
360
 
 
 
 
 
 
 
 
361	pr_info("OMAP clockevent source: %s at %lu Hz\n", clockevent_gpt.name,
362		clkev.rate);
363}
364
365/* Clocksource code */
366static struct omap_dm_timer clksrc;
367static bool use_gptimer_clksrc __initdata;
368
369/*
370 * clocksource
371 */
372static u64 clocksource_read_cycles(struct clocksource *cs)
373{
374	return (u64)__omap_dm_timer_read_counter(&clksrc,
375						     OMAP_TIMER_NONPOSTED);
376}
377
378static struct clocksource clocksource_gpt = {
379	.rating		= 300,
380	.read		= clocksource_read_cycles,
381	.mask		= CLOCKSOURCE_MASK(32),
382	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
383};
384
385static u64 notrace dmtimer_read_sched_clock(void)
386{
387	if (clksrc.reserved)
388		return __omap_dm_timer_read_counter(&clksrc,
389						    OMAP_TIMER_NONPOSTED);
390
391	return 0;
392}
393
394static const struct of_device_id omap_counter_match[] __initconst = {
395	{ .compatible = "ti,omap-counter32k", },
396	{ }
397};
398
399/* Setup free-running counter for clocksource */
400static int __init __maybe_unused omap2_sync32k_clocksource_init(void)
401{
402	int ret;
403	struct device_node *np = NULL;
404	struct omap_hwmod *oh;
405	const char *oh_name = "counter_32k";
406
407	/*
408	 * If device-tree is present, then search the DT blob
409	 * to see if the 32kHz counter is supported.
410	 */
411	if (of_have_populated_dt()) {
412		np = omap_get_timer_dt(omap_counter_match, NULL);
413		if (!np)
414			return -ENODEV;
415
 
 
416		of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
417		if (!oh_name)
418			return -ENODEV;
419	}
420
421	/*
422	 * First check hwmod data is available for sync32k counter
423	 */
424	oh = omap_hwmod_lookup(oh_name);
425	if (!oh || oh->slaves_cnt == 0)
426		return -ENODEV;
427
428	omap_hwmod_setup_one(oh_name);
429
430	ret = omap_hwmod_enable(oh);
431	if (ret) {
432		pr_warn("%s: failed to enable counter_32k module (%d)\n",
433							__func__, ret);
434		return ret;
435	}
436
437	if (!of_have_populated_dt()) {
438		void __iomem *vbase;
439
440		vbase = omap_hwmod_get_mpu_rt_va(oh);
441
442		ret = omap_init_clocksource_32k(vbase);
443		if (ret) {
444			pr_warn("%s: failed to initialize counter_32k as a clocksource (%d)\n",
445					__func__, ret);
446			omap_hwmod_idle(oh);
447		}
448	}
449	return ret;
 
 
 
 
 
 
 
 
450}
451
452static void __init omap2_gptimer_clocksource_init(int gptimer_id,
453						  const char *fck_source,
454						  const char *property)
455{
456	int res;
457
458	clksrc.id = gptimer_id;
459	clksrc.errata = omap_dm_timer_get_errata();
460
461	res = omap_dm_timer_init_one(&clksrc, fck_source, property,
462				     &clocksource_gpt.name,
463				     OMAP_TIMER_NONPOSTED);
 
 
 
 
 
 
 
 
 
464	BUG_ON(res);
465
466	__omap_dm_timer_load_start(&clksrc,
467				   OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0,
468				   OMAP_TIMER_NONPOSTED);
469	sched_clock_register(dmtimer_read_sched_clock, 32, clksrc.rate);
470
471	if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
472		pr_err("Could not register clocksource %s\n",
473			clocksource_gpt.name);
474	else
475		pr_info("OMAP clocksource: %s at %lu Hz\n",
476			clocksource_gpt.name, clksrc.rate);
477}
478
479static void __init __omap_sync32k_timer_init(int clkev_nr, const char *clkev_src,
480		const char *clkev_prop, int clksrc_nr, const char *clksrc_src,
481		const char *clksrc_prop, bool gptimer)
482{
483	omap_clk_init();
484	omap_dmtimer_init();
485	omap2_gp_clockevent_init(clkev_nr, clkev_src, clkev_prop);
486
487	/* Enable the use of clocksource="gp_timer" kernel parameter */
488	if (use_gptimer_clksrc || gptimer)
489		omap2_gptimer_clocksource_init(clksrc_nr, clksrc_src,
490						clksrc_prop);
491	else
492		omap2_sync32k_clocksource_init();
493}
494
495void __init omap_init_time(void)
496{
497	__omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
498			2, "timer_sys_ck", NULL, false);
499
500	clocksource_probe();
501}
502
503#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM43XX)
504void __init omap3_secure_sync32k_timer_init(void)
505{
506	__omap_sync32k_timer_init(12, "secure_32k_fck", "ti,timer-secure",
507			2, "timer_sys_ck", NULL, false);
508
509	clocksource_probe();
510}
511#endif /* CONFIG_ARCH_OMAP3 */
512
513#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX) || \
514	defined(CONFIG_SOC_AM43XX)
515void __init omap3_gptimer_timer_init(void)
516{
517	__omap_sync32k_timer_init(2, "timer_sys_ck", NULL,
518			1, "timer_sys_ck", "ti,timer-alwon", true);
519	if (of_have_populated_dt())
520		clocksource_probe();
521}
522#endif
523
524#if defined(CONFIG_ARCH_OMAP4) || defined(CONFIG_SOC_OMAP5) ||		\
525	defined(CONFIG_SOC_DRA7XX)
526static void __init omap4_sync32k_timer_init(void)
527{
528	__omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
529			2, "sys_clkin_ck", NULL, false);
530}
531
532void __init omap4_local_timer_init(void)
533{
534	omap4_sync32k_timer_init();
535	clocksource_probe();
536}
537#endif
538
539#if defined(CONFIG_SOC_OMAP5) || defined(CONFIG_SOC_DRA7XX)
540
541/*
542 * The realtime counter also called master counter, is a free-running
543 * counter, which is related to real time. It produces the count used
544 * by the CPU local timer peripherals in the MPU cluster. The timer counts
545 * at a rate of 6.144 MHz. Because the device operates on different clocks
546 * in different power modes, the master counter shifts operation between
547 * clocks, adjusting the increment per clock in hardware accordingly to
548 * maintain a constant count rate.
549 */
550static void __init realtime_counter_init(void)
551{
552#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
553	void __iomem *base;
554	static struct clk *sys_clk;
555	unsigned long rate;
556	unsigned int reg;
557	unsigned long long num, den;
558
559	base = ioremap(REALTIME_COUNTER_BASE, SZ_32);
560	if (!base) {
561		pr_err("%s: ioremap failed\n", __func__);
562		return;
563	}
564	sys_clk = clk_get(NULL, "sys_clkin");
565	if (IS_ERR(sys_clk)) {
566		pr_err("%s: failed to get system clock handle\n", __func__);
567		iounmap(base);
568		return;
569	}
570
571	rate = clk_get_rate(sys_clk);
572
573	if (soc_is_dra7xx()) {
574		/*
575		 * Errata i856 says the 32.768KHz crystal does not start at
576		 * power on, so the CPU falls back to an emulated 32KHz clock
577		 * based on sysclk / 610 instead. This causes the master counter
578		 * frequency to not be 6.144MHz but at sysclk / 610 * 375 / 2
579		 * (OR sysclk * 75 / 244)
580		 *
581		 * This affects at least the DRA7/AM572x 1.0, 1.1 revisions.
582		 * Of course any board built without a populated 32.768KHz
583		 * crystal would also need this fix even if the CPU is fixed
584		 * later.
585		 *
586		 * Either case can be detected by using the two speedselect bits
587		 * If they are not 0, then the 32.768KHz clock driving the
588		 * coarse counter that corrects the fine counter every time it
589		 * ticks is actually rate/610 rather than 32.768KHz and we
590		 * should compensate to avoid the 570ppm (at 20MHz, much worse
591		 * at other rates) too fast system time.
592		 */
593		reg = omap_ctrl_readl(DRA7_CTRL_CORE_BOOTSTRAP);
594		if (reg & DRA7_SPEEDSELECT_MASK) {
595			num = 75;
596			den = 244;
597			goto sysclk1_based;
598		}
599	}
600
601	/* Numerator/denumerator values refer TRM Realtime Counter section */
602	switch (rate) {
603	case 12000000:
604		num = 64;
605		den = 125;
606		break;
607	case 13000000:
608		num = 768;
609		den = 1625;
610		break;
611	case 19200000:
612		num = 8;
613		den = 25;
614		break;
615	case 20000000:
616		num = 192;
617		den = 625;
618		break;
619	case 26000000:
620		num = 384;
621		den = 1625;
622		break;
623	case 27000000:
624		num = 256;
625		den = 1125;
626		break;
627	case 38400000:
628	default:
629		/* Program it for 38.4 MHz */
630		num = 4;
631		den = 25;
632		break;
633	}
634
635sysclk1_based:
636	/* Program numerator and denumerator registers */
637	reg = readl_relaxed(base + INCREMENTER_NUMERATOR_OFFSET) &
638			NUMERATOR_DENUMERATOR_MASK;
639	reg |= num;
640	writel_relaxed(reg, base + INCREMENTER_NUMERATOR_OFFSET);
641
642	reg = readl_relaxed(base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET) &
643			NUMERATOR_DENUMERATOR_MASK;
644	reg |= den;
645	writel_relaxed(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET);
646
647	arch_timer_freq = DIV_ROUND_UP_ULL(rate * num, den);
648	set_cntfreq();
649
650	iounmap(base);
651#endif
652}
653
654void __init omap5_realtime_timer_init(void)
655{
656	omap4_sync32k_timer_init();
657	realtime_counter_init();
658
659	clocksource_probe();
660}
661#endif /* CONFIG_SOC_OMAP5 || CONFIG_SOC_DRA7XX */
662
663/**
664 * omap_timer_init - build and register timer device with an
665 * associated timer hwmod
666 * @oh:	timer hwmod pointer to be used to build timer device
667 * @user:	parameter that can be passed from calling hwmod API
668 *
669 * Called by omap_hwmod_for_each_by_class to register each of the timer
670 * devices present in the system. The number of timer devices is known
671 * by parsing through the hwmod database for a given class name. At the
672 * end of function call memory is allocated for timer device and it is
673 * registered to the framework ready to be proved by the driver.
674 */
675static int __init omap_timer_init(struct omap_hwmod *oh, void *unused)
676{
677	int id;
678	int ret = 0;
679	char *name = "omap_timer";
680	struct dmtimer_platform_data *pdata;
681	struct platform_device *pdev;
682	struct omap_timer_capability_dev_attr *timer_dev_attr;
683
684	pr_debug("%s: %s\n", __func__, oh->name);
685
686	/* on secure device, do not register secure timer */
687	timer_dev_attr = oh->dev_attr;
688	if (omap_type() != OMAP2_DEVICE_TYPE_GP && timer_dev_attr)
689		if (timer_dev_attr->timer_capability == OMAP_TIMER_SECURE)
690			return ret;
691
692	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
693	if (!pdata) {
694		pr_err("%s: No memory for [%s]\n", __func__, oh->name);
695		return -ENOMEM;
696	}
697
698	/*
699	 * Extract the IDs from name field in hwmod database
700	 * and use the same for constructing ids' for the
701	 * timer devices. In a way, we are avoiding usage of
702	 * static variable witin the function to do the same.
703	 * CAUTION: We have to be careful and make sure the
704	 * name in hwmod database does not change in which case
705	 * we might either make corresponding change here or
706	 * switch back static variable mechanism.
707	 */
708	sscanf(oh->name, "timer%2d", &id);
709
710	if (timer_dev_attr)
711		pdata->timer_capability = timer_dev_attr->timer_capability;
712
713	pdata->timer_errata = omap_dm_timer_get_errata();
714	pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
715
716	pdev = omap_device_build(name, id, oh, pdata, sizeof(*pdata));
717
718	if (IS_ERR(pdev)) {
719		pr_err("%s: Can't build omap_device for %s: %s.\n",
720			__func__, name, oh->name);
721		ret = -EINVAL;
722	}
723
724	kfree(pdata);
725
726	return ret;
727}
728
729/**
730 * omap2_dm_timer_init - top level regular device initialization
731 *
732 * Uses dedicated hwmod api to parse through hwmod database for
733 * given class name and then build and register the timer device.
734 */
735static int __init omap2_dm_timer_init(void)
736{
737	int ret;
738
739	/* If dtb is there, the devices will be created dynamically */
740	if (of_have_populated_dt())
741		return -ENODEV;
742
743	ret = omap_hwmod_for_each_by_class("timer", omap_timer_init, NULL);
744	if (unlikely(ret)) {
745		pr_err("%s: device registration failed.\n", __func__);
746		return -EINVAL;
747	}
748
749	return 0;
750}
751omap_arch_initcall(omap2_dm_timer_init);
752
753/**
754 * omap2_override_clocksource - clocksource override with user configuration
755 *
756 * Allows user to override default clocksource, using kernel parameter
757 *   clocksource="gp_timer"	(For all OMAP2PLUS architectures)
758 *
759 * Note that, here we are using same standard kernel parameter "clocksource=",
760 * and not introducing any OMAP specific interface.
761 */
762static int __init omap2_override_clocksource(char *str)
763{
764	if (!str)
765		return 0;
766	/*
767	 * For OMAP architecture, we only have two options
768	 *    - sync_32k (default)
769	 *    - gp_timer (sys_clk based)
770	 */
771	if (!strcmp(str, "gp_timer"))
772		use_gptimer_clksrc = true;
773
774	return 0;
775}
776early_param("clocksource", omap2_override_clocksource);