arch/arm/mach-prima2/timer-marco.c - kernel/msm-4.19 - Gitiles

 /*
  * System timer for CSR SiRFprimaII
  *
  * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
  *
  * Licensed under GPLv2 or later.
  */

 #include <linux/kernel.h>
 #include <linux/interrupt.h>
 #include <linux/clockchips.h>
 #include <linux/clocksource.h>
 #include <linux/bitops.h>
 #include <linux/irq.h>
 #include <linux/clk.h>
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
 #include <asm/sched_clock.h>
 #include <asm/localtimer.h>
 #include <asm/mach/time.h>

 #include "common.h"

 #define SIRFSOC_TIMER_32COUNTER_0_CTRL			0x0000
 #define SIRFSOC_TIMER_32COUNTER_1_CTRL			0x0004
 #define SIRFSOC_TIMER_MATCH_0				0x0018
 #define SIRFSOC_TIMER_MATCH_1				0x001c
 #define SIRFSOC_TIMER_COUNTER_0				0x0048
 #define SIRFSOC_TIMER_COUNTER_1				0x004c
 #define SIRFSOC_TIMER_INTR_STATUS			0x0060
 #define SIRFSOC_TIMER_WATCHDOG_EN			0x0064
 #define SIRFSOC_TIMER_64COUNTER_CTRL			0x0068
 #define SIRFSOC_TIMER_64COUNTER_LO			0x006c
 #define SIRFSOC_TIMER_64COUNTER_HI			0x0070
 #define SIRFSOC_TIMER_64COUNTER_LOAD_LO			0x0074
 #define SIRFSOC_TIMER_64COUNTER_LOAD_HI			0x0078
 #define SIRFSOC_TIMER_64COUNTER_RLATCHED_LO		0x007c
 #define SIRFSOC_TIMER_64COUNTER_RLATCHED_HI		0x0080

 #define SIRFSOC_TIMER_REG_CNT 6

 static const u32 sirfsoc_timer_reg_list[SIRFSOC_TIMER_REG_CNT] = {
 	SIRFSOC_TIMER_WATCHDOG_EN,
 	SIRFSOC_TIMER_32COUNTER_0_CTRL,
 	SIRFSOC_TIMER_32COUNTER_1_CTRL,
 	SIRFSOC_TIMER_64COUNTER_CTRL,
 	SIRFSOC_TIMER_64COUNTER_RLATCHED_LO,
 	SIRFSOC_TIMER_64COUNTER_RLATCHED_HI,
 };

 static u32 sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT];

 static void __iomem *sirfsoc_timer_base;
 static void __init sirfsoc_of_timer_map(void);

 /* disable count and interrupt */
 static inline void sirfsoc_timer_count_disable(int idx)
 {
 	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) & ~0x7,
 		sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
 }

 /* enable count and interrupt */
 static inline void sirfsoc_timer_count_enable(int idx)
 {
 	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) | 0x7,
 		sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
 }

 /* timer interrupt handler */
 static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id)
 {
 	struct clock_event_device *ce = dev_id;
 	int cpu = smp_processor_id();

 	/* clear timer interrupt */
 	writel_relaxed(BIT(cpu), sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);

 	if (ce->mode == CLOCK_EVT_MODE_ONESHOT)
 		sirfsoc_timer_count_disable(cpu);

 	ce->event_handler(ce);

 	return IRQ_HANDLED;
 }

 /* read 64-bit timer counter */
 static cycle_t sirfsoc_timer_read(struct clocksource *cs)
 {
 	u64 cycles;

 	writel_relaxed((readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
 			BIT(0)) & ~BIT(1), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);

 	cycles = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_HI);
 	cycles = (cycles << 32) | readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_LO);

 	return cycles;
 }

 static int sirfsoc_timer_set_next_event(unsigned long delta,
 	struct clock_event_device *ce)
 {
 	int cpu = smp_processor_id();

 	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0 +
 		4 * cpu);
 	writel_relaxed(delta, sirfsoc_timer_base + SIRFSOC_TIMER_MATCH_0 +
 		4 * cpu);

 	/* enable the tick */
 	sirfsoc_timer_count_enable(cpu);

 	return 0;
 }

 static void sirfsoc_timer_set_mode(enum clock_event_mode mode,
 	struct clock_event_device *ce)
 {
 	switch (mode) {
 	case CLOCK_EVT_MODE_ONESHOT:
 		/* enable in set_next_event */
 		break;
 	default:
 		break;
 	}

 	sirfsoc_timer_count_disable(smp_processor_id());
 }

 static void sirfsoc_clocksource_suspend(struct clocksource *cs)
 {
 	int i;

 	for (i = 0; i < SIRFSOC_TIMER_REG_CNT; i++)
 		sirfsoc_timer_reg_val[i] = readl_relaxed(sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
 }

 static void sirfsoc_clocksource_resume(struct clocksource *cs)
 {
 	int i;

 	for (i = 0; i < SIRFSOC_TIMER_REG_CNT - 2; i++)
 		writel_relaxed(sirfsoc_timer_reg_val[i], sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);

 	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 2],
 		sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
 	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1],
 		sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);

 	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
 		BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
 }

 static struct clock_event_device sirfsoc_clockevent = {
 	.name = "sirfsoc_clockevent",
 	.rating = 200,
 	.features = CLOCK_EVT_FEAT_ONESHOT,
 	.set_mode = sirfsoc_timer_set_mode,
 	.set_next_event = sirfsoc_timer_set_next_event,
 };

 static struct clocksource sirfsoc_clocksource = {
 	.name = "sirfsoc_clocksource",
 	.rating = 200,
 	.mask = CLOCKSOURCE_MASK(64),
 	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
 	.read = sirfsoc_timer_read,
 	.suspend = sirfsoc_clocksource_suspend,
 	.resume = sirfsoc_clocksource_resume,
 };

 static struct irqaction sirfsoc_timer_irq = {
 	.name = "sirfsoc_timer0",
 	.flags = IRQF_TIMER | IRQF_NOBALANCING,
 	.handler = sirfsoc_timer_interrupt,
 	.dev_id = &sirfsoc_clockevent,
 };

 #ifdef CONFIG_LOCAL_TIMERS

 static struct irqaction sirfsoc_timer1_irq = {
 	.name = "sirfsoc_timer1",
 	.flags = IRQF_TIMER | IRQF_NOBALANCING,
 	.handler = sirfsoc_timer_interrupt,
 };

 static int __cpuinit sirfsoc_local_timer_setup(struct clock_event_device *ce)
 {
 	/* Use existing clock_event for cpu 0 */
 	if (!smp_processor_id())
 		return 0;

 	ce->irq = sirfsoc_timer1_irq.irq;
 	ce->name = "local_timer";
 	ce->features = sirfsoc_clockevent.features;
 	ce->rating = sirfsoc_clockevent.rating;
 	ce->set_mode = sirfsoc_timer_set_mode;
 	ce->set_next_event = sirfsoc_timer_set_next_event;
 	ce->shift = sirfsoc_clockevent.shift;
 	ce->mult = sirfsoc_clockevent.mult;
 	ce->max_delta_ns = sirfsoc_clockevent.max_delta_ns;
 	ce->min_delta_ns = sirfsoc_clockevent.min_delta_ns;

 	sirfsoc_timer1_irq.dev_id = ce;
 	BUG_ON(setup_irq(ce->irq, &sirfsoc_timer1_irq));
 	irq_set_affinity(sirfsoc_timer1_irq.irq, cpumask_of(1));

 	clockevents_register_device(ce);
 	return 0;
 }

 static void sirfsoc_local_timer_stop(struct clock_event_device *ce)
 {
 	sirfsoc_timer_count_disable(1);

 	remove_irq(sirfsoc_timer1_irq.irq, &sirfsoc_timer1_irq);
 }

 static struct local_timer_ops sirfsoc_local_timer_ops __cpuinitdata = {
 	.setup	= sirfsoc_local_timer_setup,
 	.stop	= sirfsoc_local_timer_stop,
 };
 #endif /* CONFIG_LOCAL_TIMERS */

 static void __init sirfsoc_clockevent_init(void)
 {
 	clockevents_calc_mult_shift(&sirfsoc_clockevent, CLOCK_TICK_RATE, 60);

 	sirfsoc_clockevent.max_delta_ns =
 		clockevent_delta2ns(-2, &sirfsoc_clockevent);
 	sirfsoc_clockevent.min_delta_ns =
 		clockevent_delta2ns(2, &sirfsoc_clockevent);

 	sirfsoc_clockevent.cpumask = cpumask_of(0);
 	clockevents_register_device(&sirfsoc_clockevent);
 #ifdef CONFIG_LOCAL_TIMERS
 	local_timer_register(&sirfsoc_local_timer_ops);
 #endif
 }

 /* initialize the kernel jiffy timer source */
 void __init sirfsoc_marco_timer_init(void)
 {
 	unsigned long rate;
 	u32 timer_div;
 	struct clk *clk;

 	/* initialize clocking early, we want to set the OS timer */
 	sirfsoc_of_clk_init();

 	/* timer's input clock is io clock */
 	clk = clk_get_sys("io", NULL);

 	BUG_ON(IS_ERR(clk));
 	rate = clk_get_rate(clk);

 	BUG_ON(rate < CLOCK_TICK_RATE);
 	BUG_ON(rate % CLOCK_TICK_RATE);

 	sirfsoc_of_timer_map();

 	/* Initialize the timer dividers */
 	timer_div = rate / CLOCK_TICK_RATE - 1;
 	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
 	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL);
 	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_1_CTRL);

 	/* Initialize timer counters to 0 */
 	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
 	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);
 	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
 		BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
 	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0);
 	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_1);

 	/* Clear all interrupts */
 	writel_relaxed(0xFFFF, sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);

 	BUG_ON(clocksource_register_hz(&sirfsoc_clocksource, CLOCK_TICK_RATE));

 	BUG_ON(setup_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq));

 	sirfsoc_clockevent_init();
 }

 static struct of_device_id timer_ids[] = {
 	{ .compatible = "sirf,marco-tick" },
 	{},
 };

 static void __init sirfsoc_of_timer_map(void)
 {
 	struct device_node *np;

 	np = of_find_matching_node(NULL, timer_ids);
 	if (!np)
 		return;
 	sirfsoc_timer_base = of_iomap(np, 0);
 	if (!sirfsoc_timer_base)
 		panic("unable to map timer cpu registers\n");

 	sirfsoc_timer_irq.irq = irq_of_parse_and_map(np, 0);
 	if (!sirfsoc_timer_irq.irq)
 		panic("No irq passed for timer0 via DT\n");

 #ifdef CONFIG_LOCAL_TIMERS
 	sirfsoc_timer1_irq.irq = irq_of_parse_and_map(np, 1);
 	if (!sirfsoc_timer1_irq.irq)
 		panic("No irq passed for timer1 via DT\n");
 #endif

 	of_node_put(np);
 }
	/*
	* System timer for CSR SiRFprimaII
	*
	* Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
	*
	* Licensed under GPLv2 or later.
	*/

	#include <linux/kernel.h>
	#include <linux/interrupt.h>
	#include <linux/clockchips.h>
	#include <linux/clocksource.h>
	#include <linux/bitops.h>
	#include <linux/irq.h>
	#include <linux/clk.h>
	#include <linux/slab.h>
	#include <linux/of.h>
	#include <linux/of_irq.h>
	#include <linux/of_address.h>
	#include <asm/sched_clock.h>
	#include <asm/localtimer.h>
	#include <asm/mach/time.h>

	#include "common.h"

	#define SIRFSOC_TIMER_32COUNTER_0_CTRL 0x0000
	#define SIRFSOC_TIMER_32COUNTER_1_CTRL 0x0004
	#define SIRFSOC_TIMER_MATCH_0 0x0018
	#define SIRFSOC_TIMER_MATCH_1 0x001c
	#define SIRFSOC_TIMER_COUNTER_0 0x0048
	#define SIRFSOC_TIMER_COUNTER_1 0x004c
	#define SIRFSOC_TIMER_INTR_STATUS 0x0060
	#define SIRFSOC_TIMER_WATCHDOG_EN 0x0064
	#define SIRFSOC_TIMER_64COUNTER_CTRL 0x0068
	#define SIRFSOC_TIMER_64COUNTER_LO 0x006c
	#define SIRFSOC_TIMER_64COUNTER_HI 0x0070
	#define SIRFSOC_TIMER_64COUNTER_LOAD_LO 0x0074
	#define SIRFSOC_TIMER_64COUNTER_LOAD_HI 0x0078
	#define SIRFSOC_TIMER_64COUNTER_RLATCHED_LO 0x007c
	#define SIRFSOC_TIMER_64COUNTER_RLATCHED_HI 0x0080

	#define SIRFSOC_TIMER_REG_CNT 6

	static const u32 sirfsoc_timer_reg_list[SIRFSOC_TIMER_REG_CNT] = {
	SIRFSOC_TIMER_WATCHDOG_EN,
	SIRFSOC_TIMER_32COUNTER_0_CTRL,
	SIRFSOC_TIMER_32COUNTER_1_CTRL,
	SIRFSOC_TIMER_64COUNTER_CTRL,
	SIRFSOC_TIMER_64COUNTER_RLATCHED_LO,
	SIRFSOC_TIMER_64COUNTER_RLATCHED_HI,
	};

	static u32 sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT];

	static void __iomem *sirfsoc_timer_base;
	static void __init sirfsoc_of_timer_map(void);

	/* disable count and interrupt */
	static inline void sirfsoc_timer_count_disable(int idx)
	{
	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) & ~0x7,
	sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
	}

	/* enable count and interrupt */
	static inline void sirfsoc_timer_count_enable(int idx)
	{
	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) \| 0x7,
	sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
	}

	/* timer interrupt handler */
	static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id)
	{
	struct clock_event_device *ce = dev_id;
	int cpu = smp_processor_id();

	/* clear timer interrupt */
	writel_relaxed(BIT(cpu), sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);

	if (ce->mode == CLOCK_EVT_MODE_ONESHOT)
	sirfsoc_timer_count_disable(cpu);

	ce->event_handler(ce);

	return IRQ_HANDLED;
	}

	/* read 64-bit timer counter */
	static cycle_t sirfsoc_timer_read(struct clocksource *cs)
	{
	u64 cycles;

	writel_relaxed((readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) \|
	BIT(0)) & ~BIT(1), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);

	cycles = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_HI);
	cycles = (cycles << 32) \| readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_LO);

	return cycles;
	}

	static int sirfsoc_timer_set_next_event(unsigned long delta,
	struct clock_event_device *ce)
	{
	int cpu = smp_processor_id();

	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0 +
	4 * cpu);
	writel_relaxed(delta, sirfsoc_timer_base + SIRFSOC_TIMER_MATCH_0 +
	4 * cpu);

	/* enable the tick */
	sirfsoc_timer_count_enable(cpu);

	return 0;
	}

	static void sirfsoc_timer_set_mode(enum clock_event_mode mode,
	struct clock_event_device *ce)
	{
	switch (mode) {
	case CLOCK_EVT_MODE_ONESHOT:
	/* enable in set_next_event */
	break;
	default:
	break;
	}

	sirfsoc_timer_count_disable(smp_processor_id());
	}

	static void sirfsoc_clocksource_suspend(struct clocksource *cs)
	{
	int i;

	for (i = 0; i < SIRFSOC_TIMER_REG_CNT; i++)
	sirfsoc_timer_reg_val[i] = readl_relaxed(sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
	}

	static void sirfsoc_clocksource_resume(struct clocksource *cs)
	{
	int i;

	for (i = 0; i < SIRFSOC_TIMER_REG_CNT - 2; i++)
	writel_relaxed(sirfsoc_timer_reg_val[i], sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);

	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 2],
	sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1],
	sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);

	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) \|
	BIT(1) \| BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
	}

	static struct clock_event_device sirfsoc_clockevent = {
	.name = "sirfsoc_clockevent",
	.rating = 200,
	.features = CLOCK_EVT_FEAT_ONESHOT,
	.set_mode = sirfsoc_timer_set_mode,
	.set_next_event = sirfsoc_timer_set_next_event,
	};

	static struct clocksource sirfsoc_clocksource = {
	.name = "sirfsoc_clocksource",
	.rating = 200,
	.mask = CLOCKSOURCE_MASK(64),
	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
	.read = sirfsoc_timer_read,
	.suspend = sirfsoc_clocksource_suspend,
	.resume = sirfsoc_clocksource_resume,
	};

	static struct irqaction sirfsoc_timer_irq = {
	.name = "sirfsoc_timer0",
	.flags = IRQF_TIMER \| IRQF_NOBALANCING,
	.handler = sirfsoc_timer_interrupt,
	.dev_id = &sirfsoc_clockevent,
	};

	#ifdef CONFIG_LOCAL_TIMERS

	static struct irqaction sirfsoc_timer1_irq = {
	.name = "sirfsoc_timer1",
	.flags = IRQF_TIMER \| IRQF_NOBALANCING,
	.handler = sirfsoc_timer_interrupt,
	};

	static int __cpuinit sirfsoc_local_timer_setup(struct clock_event_device *ce)
	{
	/* Use existing clock_event for cpu 0 */
	if (!smp_processor_id())
	return 0;

	ce->irq = sirfsoc_timer1_irq.irq;
	ce->name = "local_timer";
	ce->features = sirfsoc_clockevent.features;
	ce->rating = sirfsoc_clockevent.rating;
	ce->set_mode = sirfsoc_timer_set_mode;
	ce->set_next_event = sirfsoc_timer_set_next_event;
	ce->shift = sirfsoc_clockevent.shift;
	ce->mult = sirfsoc_clockevent.mult;
	ce->max_delta_ns = sirfsoc_clockevent.max_delta_ns;
	ce->min_delta_ns = sirfsoc_clockevent.min_delta_ns;

	sirfsoc_timer1_irq.dev_id = ce;
	BUG_ON(setup_irq(ce->irq, &sirfsoc_timer1_irq));
	irq_set_affinity(sirfsoc_timer1_irq.irq, cpumask_of(1));

	clockevents_register_device(ce);
	return 0;
	}

	static void sirfsoc_local_timer_stop(struct clock_event_device *ce)
	{
	sirfsoc_timer_count_disable(1);

	remove_irq(sirfsoc_timer1_irq.irq, &sirfsoc_timer1_irq);
	}

	static struct local_timer_ops sirfsoc_local_timer_ops __cpuinitdata = {
	.setup = sirfsoc_local_timer_setup,
	.stop = sirfsoc_local_timer_stop,
	};
	#endif /* CONFIG_LOCAL_TIMERS */

	static void __init sirfsoc_clockevent_init(void)
	{
	clockevents_calc_mult_shift(&sirfsoc_clockevent, CLOCK_TICK_RATE, 60);

	sirfsoc_clockevent.max_delta_ns =
	clockevent_delta2ns(-2, &sirfsoc_clockevent);
	sirfsoc_clockevent.min_delta_ns =
	clockevent_delta2ns(2, &sirfsoc_clockevent);

	sirfsoc_clockevent.cpumask = cpumask_of(0);
	clockevents_register_device(&sirfsoc_clockevent);
	#ifdef CONFIG_LOCAL_TIMERS
	local_timer_register(&sirfsoc_local_timer_ops);
	#endif
	}

	/* initialize the kernel jiffy timer source */
	void __init sirfsoc_marco_timer_init(void)
	{
	unsigned long rate;
	u32 timer_div;
	struct clk *clk;

	/* initialize clocking early, we want to set the OS timer */
	sirfsoc_of_clk_init();

	/* timer's input clock is io clock */
	clk = clk_get_sys("io", NULL);

	BUG_ON(IS_ERR(clk));
	rate = clk_get_rate(clk);

	BUG_ON(rate < CLOCK_TICK_RATE);
	BUG_ON(rate % CLOCK_TICK_RATE);

	sirfsoc_of_timer_map();

	/* Initialize the timer dividers */
	timer_div = rate / CLOCK_TICK_RATE - 1;
	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL);
	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_1_CTRL);

	/* Initialize timer counters to 0 */
	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);
	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) \|
	BIT(1) \| BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0);
	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_1);

	/* Clear all interrupts */
	writel_relaxed(0xFFFF, sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);

	BUG_ON(clocksource_register_hz(&sirfsoc_clocksource, CLOCK_TICK_RATE));

	BUG_ON(setup_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq));

	sirfsoc_clockevent_init();
	}

	static struct of_device_id timer_ids[] = {
	{ .compatible = "sirf,marco-tick" },
	{},
	};

	static void __init sirfsoc_of_timer_map(void)
	{
	struct device_node *np;

	np = of_find_matching_node(NULL, timer_ids);
	if (!np)
	return;
	sirfsoc_timer_base = of_iomap(np, 0);
	if (!sirfsoc_timer_base)
	panic("unable to map timer cpu registers\n");

	sirfsoc_timer_irq.irq = irq_of_parse_and_map(np, 0);
	if (!sirfsoc_timer_irq.irq)
	panic("No irq passed for timer0 via DT\n");

	#ifdef CONFIG_LOCAL_TIMERS
	sirfsoc_timer1_irq.irq = irq_of_parse_and_map(np, 1);
	if (!sirfsoc_timer1_irq.irq)
	panic("No irq passed for timer1 via DT\n");
	#endif

	of_node_put(np);
	}