arch/arm/mach-davinci/time.c - kernel/msm-4.19 - Gitiles

 /*
  * DaVinci timer subsystem
  *
  * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
  *
  * 2007 (c) MontaVista Software, Inc. This file is licensed under
  * the terms of the GNU General Public License version 2. This program
  * is licensed "as is" without any warranty of any kind, whether express
  * or implied.
  */
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/interrupt.h>
 #include <linux/clocksource.h>
 #include <linux/clockchips.h>
 #include <linux/io.h>
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/platform_device.h>

 #include <mach/hardware.h>
 #include <asm/mach/irq.h>
 #include <asm/mach/time.h>
 #include <mach/cputype.h>
 #include <mach/time.h>
 #include "clock.h"

 static struct clock_event_device clockevent_davinci;
 static unsigned int davinci_clock_tick_rate;

 /*
  * This driver configures the 2 64-bit count-up timers as 4 independent
  * 32-bit count-up timers used as follows:
  */

 enum {
 	TID_CLOCKEVENT,
 	TID_CLOCKSOURCE,
 };

 /* Timer register offsets */
 #define PID12			0x0
 #define TIM12			0x10
 #define TIM34			0x14
 #define PRD12			0x18
 #define PRD34			0x1c
 #define TCR			0x20
 #define TGCR			0x24
 #define WDTCR			0x28

 /* Offsets of the 8 compare registers */
 #define	CMP12_0			0x60
 #define	CMP12_1			0x64
 #define	CMP12_2			0x68
 #define	CMP12_3			0x6c
 #define	CMP12_4			0x70
 #define	CMP12_5			0x74
 #define	CMP12_6			0x78
 #define	CMP12_7			0x7c

 /* Timer register bitfields */
 #define TCR_ENAMODE_DISABLE          0x0
 #define TCR_ENAMODE_ONESHOT          0x1
 #define TCR_ENAMODE_PERIODIC         0x2
 #define TCR_ENAMODE_MASK             0x3

 #define TGCR_TIMMODE_SHIFT           2
 #define TGCR_TIMMODE_64BIT_GP        0x0
 #define TGCR_TIMMODE_32BIT_UNCHAINED 0x1
 #define TGCR_TIMMODE_64BIT_WDOG      0x2
 #define TGCR_TIMMODE_32BIT_CHAINED   0x3

 #define TGCR_TIM12RS_SHIFT           0
 #define TGCR_TIM34RS_SHIFT           1
 #define TGCR_RESET                   0x0
 #define TGCR_UNRESET                 0x1
 #define TGCR_RESET_MASK              0x3

 #define WDTCR_WDEN_SHIFT             14
 #define WDTCR_WDEN_DISABLE           0x0
 #define WDTCR_WDEN_ENABLE            0x1
 #define WDTCR_WDKEY_SHIFT            16
 #define WDTCR_WDKEY_SEQ0             0xa5c6
 #define WDTCR_WDKEY_SEQ1             0xda7e

 struct timer_s {
 	char *name;
 	unsigned int id;
 	unsigned long period;
 	unsigned long opts;
 	unsigned long flags;
 	void __iomem *base;
 	unsigned long tim_off;
 	unsigned long prd_off;
 	unsigned long enamode_shift;
 	struct irqaction irqaction;
 };
 static struct timer_s timers[];

 /* values for 'opts' field of struct timer_s */
 #define TIMER_OPTS_DISABLED		0x01
 #define TIMER_OPTS_ONESHOT		0x02
 #define TIMER_OPTS_PERIODIC		0x04
 #define TIMER_OPTS_STATE_MASK		0x07

 #define TIMER_OPTS_USE_COMPARE		0x80000000
 #define USING_COMPARE(t)		((t)->opts & TIMER_OPTS_USE_COMPARE)

 static char *id_to_name[] = {
 	[T0_BOT]	= "timer0_0",
 	[T0_TOP]	= "timer0_1",
 	[T1_BOT]	= "timer1_0",
 	[T1_TOP]	= "timer1_1",
 };

 static int timer32_config(struct timer_s *t)
 {
 	u32 tcr;
 	struct davinci_soc_info *soc_info = &davinci_soc_info;

 	if (USING_COMPARE(t)) {
 		struct davinci_timer_instance *dtip =
 				soc_info->timer_info->timers;
 		int event_timer = ID_TO_TIMER(timers[TID_CLOCKEVENT].id);

 		/*
 		 * Next interrupt should be the current time reg value plus
 		 * the new period (using 32-bit unsigned addition/wrapping
 		 * to 0 on overflow).  This assumes that the clocksource
 		 * is setup to count to 2^32-1 before wrapping around to 0.
 		 */
 		__raw_writel(__raw_readl(t->base + t->tim_off) + t->period,
 			t->base + dtip[event_timer].cmp_off);
 	} else {
 		tcr = __raw_readl(t->base + TCR);

 		/* disable timer */
 		tcr &= ~(TCR_ENAMODE_MASK << t->enamode_shift);
 		__raw_writel(tcr, t->base + TCR);

 		/* reset counter to zero, set new period */
 		__raw_writel(0, t->base + t->tim_off);
 		__raw_writel(t->period, t->base + t->prd_off);

 		/* Set enable mode */
 		if (t->opts & TIMER_OPTS_ONESHOT)
 			tcr |= TCR_ENAMODE_ONESHOT << t->enamode_shift;
 		else if (t->opts & TIMER_OPTS_PERIODIC)
 			tcr |= TCR_ENAMODE_PERIODIC << t->enamode_shift;

 		__raw_writel(tcr, t->base + TCR);
 	}
 	return 0;
 }

 static inline u32 timer32_read(struct timer_s *t)
 {
 	return __raw_readl(t->base + t->tim_off);
 }

 static irqreturn_t timer_interrupt(int irq, void *dev_id)
 {
 	struct clock_event_device *evt = &clockevent_davinci;

 	evt->event_handler(evt);
 	return IRQ_HANDLED;
 }

 /* called when 32-bit counter wraps */
 static irqreturn_t freerun_interrupt(int irq, void *dev_id)
 {
 	return IRQ_HANDLED;
 }

 static struct timer_s timers[] = {
 	[TID_CLOCKEVENT] = {
 		.name      = "clockevent",
 		.opts      = TIMER_OPTS_DISABLED,
 		.irqaction = {
 			.flags   = IRQF_DISABLED | IRQF_TIMER,
 			.handler = timer_interrupt,
 		}
 	},
 	[TID_CLOCKSOURCE] = {
 		.name       = "free-run counter",
 		.period     = ~0,
 		.opts       = TIMER_OPTS_PERIODIC,
 		.irqaction = {
 			.flags   = IRQF_DISABLED | IRQF_TIMER,
 			.handler = freerun_interrupt,
 		}
 	},
 };

 static void __init timer_init(void)
 {
 	struct davinci_soc_info *soc_info = &davinci_soc_info;
 	struct davinci_timer_instance *dtip = soc_info->timer_info->timers;
 	void __iomem *base[2];
 	int i;

 	/* Global init of each 64-bit timer as a whole */
 	for(i=0; i<2; i++) {
 		u32 tgcr;

 		base[i] = ioremap(dtip[i].base, SZ_4K);
 		if (WARN_ON(!base[i]))
 			continue;

 		/* Disabled, Internal clock source */
 		__raw_writel(0, base[i] + TCR);

 		/* reset both timers, no pre-scaler for timer34 */
 		tgcr = 0;
 		__raw_writel(tgcr, base[i] + TGCR);

 		/* Set both timers to unchained 32-bit */
 		tgcr = TGCR_TIMMODE_32BIT_UNCHAINED << TGCR_TIMMODE_SHIFT;
 		__raw_writel(tgcr, base[i] + TGCR);

 		/* Unreset timers */
 		tgcr |= (TGCR_UNRESET << TGCR_TIM12RS_SHIFT) |
 			(TGCR_UNRESET << TGCR_TIM34RS_SHIFT);
 		__raw_writel(tgcr, base[i] + TGCR);

 		/* Init both counters to zero */
 		__raw_writel(0, base[i] + TIM12);
 		__raw_writel(0, base[i] + TIM34);
 	}

 	/* Init of each timer as a 32-bit timer */
 	for (i=0; i< ARRAY_SIZE(timers); i++) {
 		struct timer_s *t = &timers[i];
 		int timer = ID_TO_TIMER(t->id);
 		u32 irq;

 		t->base = base[timer];
 		if (!t->base)
 			continue;

 		if (IS_TIMER_BOT(t->id)) {
 			t->enamode_shift = 6;
 			t->tim_off = TIM12;
 			t->prd_off = PRD12;
 			irq = dtip[timer].bottom_irq;
 		} else {
 			t->enamode_shift = 22;
 			t->tim_off = TIM34;
 			t->prd_off = PRD34;
 			irq = dtip[timer].top_irq;
 		}

 		/* Register interrupt */
 		t->irqaction.name = t->name;
 		t->irqaction.dev_id = (void *)t;

 		if (t->irqaction.handler != NULL) {
 			irq = USING_COMPARE(t) ? dtip[i].cmp_irq : irq;
 			setup_irq(irq, &t->irqaction);
 		}
 	}
 }

 /*
  * clocksource
  */
 static cycle_t read_cycles(struct clocksource *cs)
 {
 	struct timer_s *t = &timers[TID_CLOCKSOURCE];

 	return (cycles_t)timer32_read(t);
 }

 static struct clocksource clocksource_davinci = {
 	.rating		= 300,
 	.read		= read_cycles,
 	.mask		= CLOCKSOURCE_MASK(32),
 	.shift		= 24,
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };

 /*
  * clockevent
  */
 static int davinci_set_next_event(unsigned long cycles,
 				  struct clock_event_device *evt)
 {
 	struct timer_s *t = &timers[TID_CLOCKEVENT];

 	t->period = cycles;
 	timer32_config(t);
 	return 0;
 }

 static void davinci_set_mode(enum clock_event_mode mode,
 			     struct clock_event_device *evt)
 {
 	struct timer_s *t = &timers[TID_CLOCKEVENT];

 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
 		t->period = davinci_clock_tick_rate / (HZ);
 		t->opts &= ~TIMER_OPTS_STATE_MASK;
 		t->opts |= TIMER_OPTS_PERIODIC;
 		timer32_config(t);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
 		t->opts &= ~TIMER_OPTS_STATE_MASK;
 		t->opts |= TIMER_OPTS_ONESHOT;
 		break;
 	case CLOCK_EVT_MODE_UNUSED:
 	case CLOCK_EVT_MODE_SHUTDOWN:
 		t->opts &= ~TIMER_OPTS_STATE_MASK;
 		t->opts |= TIMER_OPTS_DISABLED;
 		break;
 	case CLOCK_EVT_MODE_RESUME:
 		break;
 	}
 }

 static struct clock_event_device clockevent_davinci = {
 	.features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
 	.shift		= 32,
 	.set_next_event	= davinci_set_next_event,
 	.set_mode	= davinci_set_mode,
 };


 static void __init davinci_timer_init(void)
 {
 	struct clk *timer_clk;
 	struct davinci_soc_info *soc_info = &davinci_soc_info;
 	unsigned int clockevent_id;
 	unsigned int clocksource_id;
 	static char err[] __initdata = KERN_ERR
 		"%s: can't register clocksource!\n";
 	int i;

 	clockevent_id = soc_info->timer_info->clockevent_id;
 	clocksource_id = soc_info->timer_info->clocksource_id;

 	timers[TID_CLOCKEVENT].id = clockevent_id;
 	timers[TID_CLOCKSOURCE].id = clocksource_id;

 	/*
 	 * If using same timer for both clock events & clocksource,
 	 * a compare register must be used to generate an event interrupt.
 	 * This is equivalent to a oneshot timer only (not periodic).
 	 */
 	if (clockevent_id == clocksource_id) {
 		struct davinci_timer_instance *dtip =
 				soc_info->timer_info->timers;
 		int event_timer = ID_TO_TIMER(clockevent_id);

 		/* Only bottom timers can use compare regs */
 		if (IS_TIMER_TOP(clockevent_id))
 			pr_warning("davinci_timer_init: Invalid use"
 				" of system timers.  Results unpredictable.\n");
 		else if ((dtip[event_timer].cmp_off == 0)
 				|| (dtip[event_timer].cmp_irq == 0))
 			pr_warning("davinci_timer_init:  Invalid timer instance"
 				" setup.  Results unpredictable.\n");
 		else {
 			timers[TID_CLOCKEVENT].opts |= TIMER_OPTS_USE_COMPARE;
 			clockevent_davinci.features = CLOCK_EVT_FEAT_ONESHOT;
 		}
 	}

 	timer_clk = clk_get(NULL, "timer0");
 	BUG_ON(IS_ERR(timer_clk));
 	clk_enable(timer_clk);

 	/* init timer hw */
 	timer_init();

 	davinci_clock_tick_rate = clk_get_rate(timer_clk);

 	/* setup clocksource */
 	clocksource_davinci.name = id_to_name[clocksource_id];
 	clocksource_davinci.mult =
 		clocksource_khz2mult(davinci_clock_tick_rate/1000,
 				     clocksource_davinci.shift);
 	if (clocksource_register(&clocksource_davinci))
 		printk(err, clocksource_davinci.name);

 	/* setup clockevent */
 	clockevent_davinci.name = id_to_name[timers[TID_CLOCKEVENT].id];
 	clockevent_davinci.mult = div_sc(davinci_clock_tick_rate, NSEC_PER_SEC,
 					 clockevent_davinci.shift);
 	clockevent_davinci.max_delta_ns =
 		clockevent_delta2ns(0xfffffffe, &clockevent_davinci);
 	clockevent_davinci.min_delta_ns = 50000; /* 50 usec */

 	clockevent_davinci.cpumask = cpumask_of(0);
 	clockevents_register_device(&clockevent_davinci);

 	for (i=0; i< ARRAY_SIZE(timers); i++)
 		timer32_config(&timers[i]);
 }

 struct sys_timer davinci_timer = {
 	.init   = davinci_timer_init,
 };


 /* reset board using watchdog timer */
 void davinci_watchdog_reset(struct platform_device *pdev)
 {
 	u32 tgcr, wdtcr;
 	void __iomem *base;
 	struct clk *wd_clk;

 	base = ioremap(pdev->resource[0].start, SZ_4K);
 	if (WARN_ON(!base))
 		return;

 	wd_clk = clk_get(&pdev->dev, NULL);
 	if (WARN_ON(IS_ERR(wd_clk)))
 		return;
 	clk_enable(wd_clk);

 	/* disable, internal clock source */
 	__raw_writel(0, base + TCR);

 	/* reset timer, set mode to 64-bit watchdog, and unreset */
 	tgcr = 0;
 	__raw_writel(tgcr, base + TGCR);
 	tgcr = TGCR_TIMMODE_64BIT_WDOG << TGCR_TIMMODE_SHIFT;
 	tgcr |= (TGCR_UNRESET << TGCR_TIM12RS_SHIFT) |
 		(TGCR_UNRESET << TGCR_TIM34RS_SHIFT);
 	__raw_writel(tgcr, base + TGCR);

 	/* clear counter and period regs */
 	__raw_writel(0, base + TIM12);
 	__raw_writel(0, base + TIM34);
 	__raw_writel(0, base + PRD12);
 	__raw_writel(0, base + PRD34);

 	/* put watchdog in pre-active state */
 	wdtcr = __raw_readl(base + WDTCR);
 	wdtcr = (WDTCR_WDKEY_SEQ0 << WDTCR_WDKEY_SHIFT) |
 		(WDTCR_WDEN_ENABLE << WDTCR_WDEN_SHIFT);
 	__raw_writel(wdtcr, base + WDTCR);

 	/* put watchdog in active state */
 	wdtcr = (WDTCR_WDKEY_SEQ1 << WDTCR_WDKEY_SHIFT) |
 		(WDTCR_WDEN_ENABLE << WDTCR_WDEN_SHIFT);
 	__raw_writel(wdtcr, base + WDTCR);

 	/* write an invalid value to the WDKEY field to trigger
 	 * a watchdog reset */
 	wdtcr = 0x00004000;
 	__raw_writel(wdtcr, base + WDTCR);
 }
	/*
	* DaVinci timer subsystem
	*
	* Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
	*
	* 2007 (c) MontaVista Software, Inc. This file is licensed under
	* the terms of the GNU General Public License version 2. This program
	* is licensed "as is" without any warranty of any kind, whether express
	* or implied.
	*/
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/types.h>
	#include <linux/interrupt.h>
	#include <linux/clocksource.h>
	#include <linux/clockchips.h>
	#include <linux/io.h>
	#include <linux/clk.h>
	#include <linux/err.h>
	#include <linux/platform_device.h>

	#include <mach/hardware.h>
	#include <asm/mach/irq.h>
	#include <asm/mach/time.h>
	#include <mach/cputype.h>
	#include <mach/time.h>
	#include "clock.h"

	static struct clock_event_device clockevent_davinci;
	static unsigned int davinci_clock_tick_rate;

	/*
	* This driver configures the 2 64-bit count-up timers as 4 independent
	* 32-bit count-up timers used as follows:
	*/

	enum {
	TID_CLOCKEVENT,
	TID_CLOCKSOURCE,
	};

	/* Timer register offsets */
	#define PID12 0x0
	#define TIM12 0x10
	#define TIM34 0x14
	#define PRD12 0x18
	#define PRD34 0x1c
	#define TCR 0x20
	#define TGCR 0x24
	#define WDTCR 0x28

	/* Offsets of the 8 compare registers */
	#define CMP12_0 0x60
	#define CMP12_1 0x64
	#define CMP12_2 0x68
	#define CMP12_3 0x6c
	#define CMP12_4 0x70
	#define CMP12_5 0x74
	#define CMP12_6 0x78
	#define CMP12_7 0x7c

	/* Timer register bitfields */
	#define TCR_ENAMODE_DISABLE 0x0
	#define TCR_ENAMODE_ONESHOT 0x1
	#define TCR_ENAMODE_PERIODIC 0x2
	#define TCR_ENAMODE_MASK 0x3

	#define TGCR_TIMMODE_SHIFT 2
	#define TGCR_TIMMODE_64BIT_GP 0x0
	#define TGCR_TIMMODE_32BIT_UNCHAINED 0x1
	#define TGCR_TIMMODE_64BIT_WDOG 0x2
	#define TGCR_TIMMODE_32BIT_CHAINED 0x3

	#define TGCR_TIM12RS_SHIFT 0
	#define TGCR_TIM34RS_SHIFT 1
	#define TGCR_RESET 0x0
	#define TGCR_UNRESET 0x1
	#define TGCR_RESET_MASK 0x3

	#define WDTCR_WDEN_SHIFT 14
	#define WDTCR_WDEN_DISABLE 0x0
	#define WDTCR_WDEN_ENABLE 0x1
	#define WDTCR_WDKEY_SHIFT 16
	#define WDTCR_WDKEY_SEQ0 0xa5c6
	#define WDTCR_WDKEY_SEQ1 0xda7e

	struct timer_s {
	char *name;
	unsigned int id;
	unsigned long period;
	unsigned long opts;
	unsigned long flags;
	void __iomem *base;
	unsigned long tim_off;
	unsigned long prd_off;
	unsigned long enamode_shift;
	struct irqaction irqaction;
	};
	static struct timer_s timers[];

	/* values for 'opts' field of struct timer_s */
	#define TIMER_OPTS_DISABLED 0x01
	#define TIMER_OPTS_ONESHOT 0x02
	#define TIMER_OPTS_PERIODIC 0x04
	#define TIMER_OPTS_STATE_MASK 0x07

	#define TIMER_OPTS_USE_COMPARE 0x80000000
	#define USING_COMPARE(t) ((t)->opts & TIMER_OPTS_USE_COMPARE)

	static char *id_to_name[] = {
	[T0_BOT] = "timer0_0",
	[T0_TOP] = "timer0_1",
	[T1_BOT] = "timer1_0",
	[T1_TOP] = "timer1_1",
	};

	static int timer32_config(struct timer_s *t)
	{
	u32 tcr;
	struct davinci_soc_info *soc_info = &davinci_soc_info;

	if (USING_COMPARE(t)) {
	struct davinci_timer_instance *dtip =
	soc_info->timer_info->timers;
	int event_timer = ID_TO_TIMER(timers[TID_CLOCKEVENT].id);

	/*
	* Next interrupt should be the current time reg value plus
	* the new period (using 32-bit unsigned addition/wrapping
	* to 0 on overflow). This assumes that the clocksource
	* is setup to count to 2^32-1 before wrapping around to 0.
	*/
	__raw_writel(__raw_readl(t->base + t->tim_off) + t->period,
	t->base + dtip[event_timer].cmp_off);
	} else {
	tcr = __raw_readl(t->base + TCR);

	/* disable timer */
	tcr &= ~(TCR_ENAMODE_MASK << t->enamode_shift);
	__raw_writel(tcr, t->base + TCR);

	/* reset counter to zero, set new period */
	__raw_writel(0, t->base + t->tim_off);
	__raw_writel(t->period, t->base + t->prd_off);

	/* Set enable mode */
	if (t->opts & TIMER_OPTS_ONESHOT)
	tcr \|= TCR_ENAMODE_ONESHOT << t->enamode_shift;
	else if (t->opts & TIMER_OPTS_PERIODIC)
	tcr \|= TCR_ENAMODE_PERIODIC << t->enamode_shift;

	__raw_writel(tcr, t->base + TCR);
	}
	return 0;
	}

	static inline u32 timer32_read(struct timer_s *t)
	{
	return __raw_readl(t->base + t->tim_off);
	}

	static irqreturn_t timer_interrupt(int irq, void *dev_id)
	{
	struct clock_event_device *evt = &clockevent_davinci;

	evt->event_handler(evt);
	return IRQ_HANDLED;
	}

	/* called when 32-bit counter wraps */
	static irqreturn_t freerun_interrupt(int irq, void *dev_id)
	{
	return IRQ_HANDLED;
	}

	static struct timer_s timers[] = {
	[TID_CLOCKEVENT] = {
	.name = "clockevent",
	.opts = TIMER_OPTS_DISABLED,
	.irqaction = {
	.flags = IRQF_DISABLED \| IRQF_TIMER,
	.handler = timer_interrupt,
	}
	},
	[TID_CLOCKSOURCE] = {
	.name = "free-run counter",
	.period = ~0,
	.opts = TIMER_OPTS_PERIODIC,
	.irqaction = {
	.flags = IRQF_DISABLED \| IRQF_TIMER,
	.handler = freerun_interrupt,
	}
	},
	};

	static void __init timer_init(void)
	{
	struct davinci_soc_info *soc_info = &davinci_soc_info;
	struct davinci_timer_instance *dtip = soc_info->timer_info->timers;
	void __iomem *base[2];
	int i;

	/* Global init of each 64-bit timer as a whole */
	for(i=0; i<2; i++) {
	u32 tgcr;

	base[i] = ioremap(dtip[i].base, SZ_4K);
	if (WARN_ON(!base[i]))
	continue;

	/* Disabled, Internal clock source */
	__raw_writel(0, base[i] + TCR);

	/* reset both timers, no pre-scaler for timer34 */
	tgcr = 0;
	__raw_writel(tgcr, base[i] + TGCR);

	/* Set both timers to unchained 32-bit */
	tgcr = TGCR_TIMMODE_32BIT_UNCHAINED << TGCR_TIMMODE_SHIFT;
	__raw_writel(tgcr, base[i] + TGCR);

	/* Unreset timers */
	tgcr \|= (TGCR_UNRESET << TGCR_TIM12RS_SHIFT) \|
	(TGCR_UNRESET << TGCR_TIM34RS_SHIFT);
	__raw_writel(tgcr, base[i] + TGCR);

	/* Init both counters to zero */
	__raw_writel(0, base[i] + TIM12);
	__raw_writel(0, base[i] + TIM34);
	}

	/* Init of each timer as a 32-bit timer */
	for (i=0; i< ARRAY_SIZE(timers); i++) {
	struct timer_s *t = &timers[i];
	int timer = ID_TO_TIMER(t->id);
	u32 irq;

	t->base = base[timer];
	if (!t->base)
	continue;

	if (IS_TIMER_BOT(t->id)) {
	t->enamode_shift = 6;
	t->tim_off = TIM12;
	t->prd_off = PRD12;
	irq = dtip[timer].bottom_irq;
	} else {
	t->enamode_shift = 22;
	t->tim_off = TIM34;
	t->prd_off = PRD34;
	irq = dtip[timer].top_irq;
	}

	/* Register interrupt */
	t->irqaction.name = t->name;
	t->irqaction.dev_id = (void *)t;

	if (t->irqaction.handler != NULL) {
	irq = USING_COMPARE(t) ? dtip[i].cmp_irq : irq;
	setup_irq(irq, &t->irqaction);
	}
	}
	}

	/*
	* clocksource
	*/
	static cycle_t read_cycles(struct clocksource *cs)
	{
	struct timer_s *t = &timers[TID_CLOCKSOURCE];

	return (cycles_t)timer32_read(t);
	}

	static struct clocksource clocksource_davinci = {
	.rating = 300,
	.read = read_cycles,
	.mask = CLOCKSOURCE_MASK(32),
	.shift = 24,
	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
	};

	/*
	* clockevent
	*/
	static int davinci_set_next_event(unsigned long cycles,
	struct clock_event_device *evt)
	{
	struct timer_s *t = &timers[TID_CLOCKEVENT];

	t->period = cycles;
	timer32_config(t);
	return 0;
	}

	static void davinci_set_mode(enum clock_event_mode mode,
	struct clock_event_device *evt)
	{
	struct timer_s *t = &timers[TID_CLOCKEVENT];

	switch (mode) {
	case CLOCK_EVT_MODE_PERIODIC:
	t->period = davinci_clock_tick_rate / (HZ);
	t->opts &= ~TIMER_OPTS_STATE_MASK;
	t->opts \|= TIMER_OPTS_PERIODIC;
	timer32_config(t);
	break;
	case CLOCK_EVT_MODE_ONESHOT:
	t->opts &= ~TIMER_OPTS_STATE_MASK;
	t->opts \|= TIMER_OPTS_ONESHOT;
	break;
	case CLOCK_EVT_MODE_UNUSED:
	case CLOCK_EVT_MODE_SHUTDOWN:
	t->opts &= ~TIMER_OPTS_STATE_MASK;
	t->opts \|= TIMER_OPTS_DISABLED;
	break;
	case CLOCK_EVT_MODE_RESUME:
	break;
	}
	}

	static struct clock_event_device clockevent_davinci = {
	.features = CLOCK_EVT_FEAT_PERIODIC \| CLOCK_EVT_FEAT_ONESHOT,
	.shift = 32,
	.set_next_event = davinci_set_next_event,
	.set_mode = davinci_set_mode,
	};


	static void __init davinci_timer_init(void)
	{
	struct clk *timer_clk;
	struct davinci_soc_info *soc_info = &davinci_soc_info;
	unsigned int clockevent_id;
	unsigned int clocksource_id;
	static char err[] __initdata = KERN_ERR
	"%s: can't register clocksource!\n";
	int i;

	clockevent_id = soc_info->timer_info->clockevent_id;
	clocksource_id = soc_info->timer_info->clocksource_id;

	timers[TID_CLOCKEVENT].id = clockevent_id;
	timers[TID_CLOCKSOURCE].id = clocksource_id;

	/*
	* If using same timer for both clock events & clocksource,
	* a compare register must be used to generate an event interrupt.
	* This is equivalent to a oneshot timer only (not periodic).
	*/
	if (clockevent_id == clocksource_id) {
	struct davinci_timer_instance *dtip =
	soc_info->timer_info->timers;
	int event_timer = ID_TO_TIMER(clockevent_id);

	/* Only bottom timers can use compare regs */
	if (IS_TIMER_TOP(clockevent_id))
	pr_warning("davinci_timer_init: Invalid use"
	" of system timers. Results unpredictable.\n");
	else if ((dtip[event_timer].cmp_off == 0)
	\|\| (dtip[event_timer].cmp_irq == 0))
	pr_warning("davinci_timer_init: Invalid timer instance"
	" setup. Results unpredictable.\n");
	else {
	timers[TID_CLOCKEVENT].opts \|= TIMER_OPTS_USE_COMPARE;
	clockevent_davinci.features = CLOCK_EVT_FEAT_ONESHOT;
	}
	}

	timer_clk = clk_get(NULL, "timer0");
	BUG_ON(IS_ERR(timer_clk));
	clk_enable(timer_clk);

	/* init timer hw */
	timer_init();

	davinci_clock_tick_rate = clk_get_rate(timer_clk);

	/* setup clocksource */
	clocksource_davinci.name = id_to_name[clocksource_id];
	clocksource_davinci.mult =
	clocksource_khz2mult(davinci_clock_tick_rate/1000,
	clocksource_davinci.shift);
	if (clocksource_register(&clocksource_davinci))
	printk(err, clocksource_davinci.name);

	/* setup clockevent */
	clockevent_davinci.name = id_to_name[timers[TID_CLOCKEVENT].id];
	clockevent_davinci.mult = div_sc(davinci_clock_tick_rate, NSEC_PER_SEC,
	clockevent_davinci.shift);
	clockevent_davinci.max_delta_ns =
	clockevent_delta2ns(0xfffffffe, &clockevent_davinci);
	clockevent_davinci.min_delta_ns = 50000; /* 50 usec */

	clockevent_davinci.cpumask = cpumask_of(0);
	clockevents_register_device(&clockevent_davinci);

	for (i=0; i< ARRAY_SIZE(timers); i++)
	timer32_config(&timers[i]);
	}

	struct sys_timer davinci_timer = {
	.init = davinci_timer_init,
	};


	/* reset board using watchdog timer */
	void davinci_watchdog_reset(struct platform_device *pdev)
	{
	u32 tgcr, wdtcr;
	void __iomem *base;
	struct clk *wd_clk;

	base = ioremap(pdev->resource[0].start, SZ_4K);
	if (WARN_ON(!base))
	return;

	wd_clk = clk_get(&pdev->dev, NULL);
	if (WARN_ON(IS_ERR(wd_clk)))
	return;
	clk_enable(wd_clk);

	/* disable, internal clock source */
	__raw_writel(0, base + TCR);

	/* reset timer, set mode to 64-bit watchdog, and unreset */
	tgcr = 0;
	__raw_writel(tgcr, base + TGCR);
	tgcr = TGCR_TIMMODE_64BIT_WDOG << TGCR_TIMMODE_SHIFT;
	tgcr \|= (TGCR_UNRESET << TGCR_TIM12RS_SHIFT) \|
	(TGCR_UNRESET << TGCR_TIM34RS_SHIFT);
	__raw_writel(tgcr, base + TGCR);

	/* clear counter and period regs */
	__raw_writel(0, base + TIM12);
	__raw_writel(0, base + TIM34);
	__raw_writel(0, base + PRD12);
	__raw_writel(0, base + PRD34);

	/* put watchdog in pre-active state */
	wdtcr = __raw_readl(base + WDTCR);
	wdtcr = (WDTCR_WDKEY_SEQ0 << WDTCR_WDKEY_SHIFT) \|
	(WDTCR_WDEN_ENABLE << WDTCR_WDEN_SHIFT);
	__raw_writel(wdtcr, base + WDTCR);

	/* put watchdog in active state */
	wdtcr = (WDTCR_WDKEY_SEQ1 << WDTCR_WDKEY_SHIFT) \|
	(WDTCR_WDEN_ENABLE << WDTCR_WDEN_SHIFT);
	__raw_writel(wdtcr, base + WDTCR);

	/* write an invalid value to the WDKEY field to trigger
	* a watchdog reset */
	wdtcr = 0x00004000;
	__raw_writel(wdtcr, base + WDTCR);
	}