arch/arm/mach-msm/timer.c - maze/linux - Git at Google

 /*
  *
  * Copyright (C) 2007 Google, Inc.
  * Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
  * may be copied, distributed, and modified under those terms.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  */

 #include <linux/clocksource.h>
 #include <linux/clockchips.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/io.h>

 #include <asm/mach/time.h>
 #include <asm/hardware/gic.h>
 #include <asm/localtimer.h>
 #include <asm/sched_clock.h>

 #include <mach/msm_iomap.h>
 #include <mach/cpu.h>
 #include <mach/board.h>

 #define TIMER_MATCH_VAL         0x0000
 #define TIMER_COUNT_VAL         0x0004
 #define TIMER_ENABLE            0x0008
 #define TIMER_ENABLE_CLR_ON_MATCH_EN    BIT(1)
 #define TIMER_ENABLE_EN                 BIT(0)
 #define TIMER_CLEAR             0x000C
 #define DGT_CLK_CTL             0x0034
 #define DGT_CLK_CTL_DIV_4	0x3

 #define GPT_HZ 32768

 #define MSM_DGT_SHIFT 5

 static void __iomem *event_base;

 static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
 {
 	struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
 	/* Stop the timer tick */
 	if (evt->mode == CLOCK_EVT_MODE_ONESHOT) {
 		u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
 		ctrl &= ~TIMER_ENABLE_EN;
 		writel_relaxed(ctrl, event_base + TIMER_ENABLE);
 	}
 	evt->event_handler(evt);
 	return IRQ_HANDLED;
 }

 static int msm_timer_set_next_event(unsigned long cycles,
 				    struct clock_event_device *evt)
 {
 	u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);

 	writel_relaxed(0, event_base + TIMER_CLEAR);
 	writel_relaxed(cycles, event_base + TIMER_MATCH_VAL);
 	writel_relaxed(ctrl | TIMER_ENABLE_EN, event_base + TIMER_ENABLE);
 	return 0;
 }

 static void msm_timer_set_mode(enum clock_event_mode mode,
 			      struct clock_event_device *evt)
 {
 	u32 ctrl;

 	ctrl = readl_relaxed(event_base + TIMER_ENABLE);
 	ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN);

 	switch (mode) {
 	case CLOCK_EVT_MODE_RESUME:
 	case CLOCK_EVT_MODE_PERIODIC:
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
 		/* Timer is enabled in set_next_event */
 		break;
 	case CLOCK_EVT_MODE_UNUSED:
 	case CLOCK_EVT_MODE_SHUTDOWN:
 		break;
 	}
 	writel_relaxed(ctrl, event_base + TIMER_ENABLE);
 }

 static struct clock_event_device msm_clockevent = {
 	.name		= "gp_timer",
 	.features	= CLOCK_EVT_FEAT_ONESHOT,
 	.rating		= 200,
 	.set_next_event	= msm_timer_set_next_event,
 	.set_mode	= msm_timer_set_mode,
 };

 static union {
 	struct clock_event_device *evt;
 	struct clock_event_device __percpu **percpu_evt;
 } msm_evt;

 static void __iomem *source_base;

 static notrace cycle_t msm_read_timer_count(struct clocksource *cs)
 {
 	return readl_relaxed(source_base + TIMER_COUNT_VAL);
 }

 static notrace cycle_t msm_read_timer_count_shift(struct clocksource *cs)
 {
 	/*
 	 * Shift timer count down by a constant due to unreliable lower bits
 	 * on some targets.
 	 */
 	return msm_read_timer_count(cs) >> MSM_DGT_SHIFT;
 }

 static struct clocksource msm_clocksource = {
 	.name	= "dg_timer",
 	.rating	= 300,
 	.read	= msm_read_timer_count,
 	.mask	= CLOCKSOURCE_MASK(32),
 	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
 };

 #ifdef CONFIG_LOCAL_TIMERS
 static int __cpuinit msm_local_timer_setup(struct clock_event_device *evt)
 {
 	/* Use existing clock_event for cpu 0 */
 	if (!smp_processor_id())
 		return 0;

 	writel_relaxed(0, event_base + TIMER_ENABLE);
 	writel_relaxed(0, event_base + TIMER_CLEAR);
 	writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
 	evt->irq = msm_clockevent.irq;
 	evt->name = "local_timer";
 	evt->features = msm_clockevent.features;
 	evt->rating = msm_clockevent.rating;
 	evt->set_mode = msm_timer_set_mode;
 	evt->set_next_event = msm_timer_set_next_event;
 	evt->shift = msm_clockevent.shift;
 	evt->mult = div_sc(GPT_HZ, NSEC_PER_SEC, evt->shift);
 	evt->max_delta_ns = clockevent_delta2ns(0xf0000000, evt);
 	evt->min_delta_ns = clockevent_delta2ns(4, evt);

 	*__this_cpu_ptr(msm_evt.percpu_evt) = evt;
 	clockevents_register_device(evt);
 	enable_percpu_irq(evt->irq, 0);
 	return 0;
 }

 static void msm_local_timer_stop(struct clock_event_device *evt)
 {
 	evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
 	disable_percpu_irq(evt->irq);
 }

 static struct local_timer_ops msm_local_timer_ops __cpuinitdata = {
 	.setup	= msm_local_timer_setup,
 	.stop	= msm_local_timer_stop,
 };
 #endif /* CONFIG_LOCAL_TIMERS */

 static notrace u32 msm_sched_clock_read(void)
 {
 	return msm_clocksource.read(&msm_clocksource);
 }

 static void __init msm_timer_init(void)
 {
 	struct clock_event_device *ce = &msm_clockevent;
 	struct clocksource *cs = &msm_clocksource;
 	int res;
 	u32 dgt_hz;

 	if (cpu_is_msm7x01()) {
 		event_base = MSM_CSR_BASE;
 		source_base = MSM_CSR_BASE + 0x10;
 		dgt_hz = 19200000 >> MSM_DGT_SHIFT; /* 600 KHz */
 		cs->read = msm_read_timer_count_shift;
 		cs->mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT));
 	} else if (cpu_is_msm7x30()) {
 		event_base = MSM_CSR_BASE + 0x04;
 		source_base = MSM_CSR_BASE + 0x24;
 		dgt_hz = 24576000 / 4;
 	} else if (cpu_is_qsd8x50()) {
 		event_base = MSM_CSR_BASE;
 		source_base = MSM_CSR_BASE + 0x10;
 		dgt_hz = 19200000 / 4;
 	} else if (cpu_is_msm8x60() || cpu_is_msm8960()) {
 		event_base = MSM_TMR_BASE + 0x04;
 		/* Use CPU0's timer as the global clock source. */
 		source_base = MSM_TMR0_BASE + 0x24;
 		dgt_hz = 27000000 / 4;
 		writel_relaxed(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL);
 	} else
 		BUG();

 	writel_relaxed(0, event_base + TIMER_ENABLE);
 	writel_relaxed(0, event_base + TIMER_CLEAR);
 	writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
 	ce->cpumask = cpumask_of(0);

 	ce->irq = INT_GP_TIMER_EXP;
 	clockevents_config_and_register(ce, GPT_HZ, 4, 0xffffffff);
 	if (cpu_is_msm8x60() || cpu_is_msm8960()) {
 		msm_evt.percpu_evt = alloc_percpu(struct clock_event_device *);
 		if (!msm_evt.percpu_evt) {
 			pr_err("memory allocation failed for %s\n", ce->name);
 			goto err;
 		}
 		*__this_cpu_ptr(msm_evt.percpu_evt) = ce;
 		res = request_percpu_irq(ce->irq, msm_timer_interrupt,
 					 ce->name, msm_evt.percpu_evt);
 		if (!res) {
 			enable_percpu_irq(ce->irq, 0);
 #ifdef CONFIG_LOCAL_TIMERS
 			local_timer_register(&msm_local_timer_ops);
 #endif
 		}
 	} else {
 		msm_evt.evt = ce;
 		res = request_irq(ce->irq, msm_timer_interrupt,
 				  IRQF_TIMER | IRQF_NOBALANCING |
 				  IRQF_TRIGGER_RISING, ce->name, &msm_evt.evt);
 	}

 	if (res)
 		pr_err("request_irq failed for %s\n", ce->name);
 err:
 	writel_relaxed(TIMER_ENABLE_EN, source_base + TIMER_ENABLE);
 	res = clocksource_register_hz(cs, dgt_hz);
 	if (res)
 		pr_err("clocksource_register failed\n");
 	setup_sched_clock(msm_sched_clock_read,
 			cpu_is_msm7x01() ? 32 - MSM_DGT_SHIFT : 32, dgt_hz);
 }

 struct sys_timer msm_timer = {
 	.init = msm_timer_init
 };
	/*
	*
	* Copyright (C) 2007 Google, Inc.
	* Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
	*
	* This software is licensed under the terms of the GNU General Public
	* License version 2, as published by the Free Software Foundation, and
	* may be copied, distributed, and modified under those terms.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	*/

	#include <linux/clocksource.h>
	#include <linux/clockchips.h>
	#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/irq.h>
	#include <linux/io.h>

	#include <asm/mach/time.h>
	#include <asm/hardware/gic.h>
	#include <asm/localtimer.h>
	#include <asm/sched_clock.h>

	#include <mach/msm_iomap.h>
	#include <mach/cpu.h>
	#include <mach/board.h>

	#define TIMER_MATCH_VAL 0x0000
	#define TIMER_COUNT_VAL 0x0004
	#define TIMER_ENABLE 0x0008
	#define TIMER_ENABLE_CLR_ON_MATCH_EN BIT(1)
	#define TIMER_ENABLE_EN BIT(0)
	#define TIMER_CLEAR 0x000C
	#define DGT_CLK_CTL 0x0034
	#define DGT_CLK_CTL_DIV_4 0x3

	#define GPT_HZ 32768

	#define MSM_DGT_SHIFT 5

	static void __iomem *event_base;

	static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
	{
	struct clock_event_device evt = (struct clock_event_device **)dev_id;
	/* Stop the timer tick */
	if (evt->mode == CLOCK_EVT_MODE_ONESHOT) {
	u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
	ctrl &= ~TIMER_ENABLE_EN;
	writel_relaxed(ctrl, event_base + TIMER_ENABLE);
	}
	evt->event_handler(evt);
	return IRQ_HANDLED;
	}

	static int msm_timer_set_next_event(unsigned long cycles,
	struct clock_event_device *evt)
	{
	u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);

	writel_relaxed(0, event_base + TIMER_CLEAR);
	writel_relaxed(cycles, event_base + TIMER_MATCH_VAL);
	writel_relaxed(ctrl \| TIMER_ENABLE_EN, event_base + TIMER_ENABLE);
	return 0;
	}

	static void msm_timer_set_mode(enum clock_event_mode mode,
	struct clock_event_device *evt)
	{
	u32 ctrl;

	ctrl = readl_relaxed(event_base + TIMER_ENABLE);
	ctrl &= ~(TIMER_ENABLE_EN \| TIMER_ENABLE_CLR_ON_MATCH_EN);

	switch (mode) {
	case CLOCK_EVT_MODE_RESUME:
	case CLOCK_EVT_MODE_PERIODIC:
	break;
	case CLOCK_EVT_MODE_ONESHOT:
	/* Timer is enabled in set_next_event */
	break;
	case CLOCK_EVT_MODE_UNUSED:
	case CLOCK_EVT_MODE_SHUTDOWN:
	break;
	}
	writel_relaxed(ctrl, event_base + TIMER_ENABLE);
	}

	static struct clock_event_device msm_clockevent = {
	.name = "gp_timer",
	.features = CLOCK_EVT_FEAT_ONESHOT,
	.rating = 200,
	.set_next_event = msm_timer_set_next_event,
	.set_mode = msm_timer_set_mode,
	};

	static union {
	struct clock_event_device *evt;
	struct clock_event_device __percpu **percpu_evt;
	} msm_evt;

	static void __iomem *source_base;

	static notrace cycle_t msm_read_timer_count(struct clocksource *cs)
	{
	return readl_relaxed(source_base + TIMER_COUNT_VAL);
	}

	static notrace cycle_t msm_read_timer_count_shift(struct clocksource *cs)
	{
	/*
	* Shift timer count down by a constant due to unreliable lower bits
	* on some targets.
	*/
	return msm_read_timer_count(cs) >> MSM_DGT_SHIFT;
	}

	static struct clocksource msm_clocksource = {
	.name = "dg_timer",
	.rating = 300,
	.read = msm_read_timer_count,
	.mask = CLOCKSOURCE_MASK(32),
	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
	};

	#ifdef CONFIG_LOCAL_TIMERS
	static int __cpuinit msm_local_timer_setup(struct clock_event_device *evt)
	{
	/* Use existing clock_event for cpu 0 */
	if (!smp_processor_id())
	return 0;

	writel_relaxed(0, event_base + TIMER_ENABLE);
	writel_relaxed(0, event_base + TIMER_CLEAR);
	writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
	evt->irq = msm_clockevent.irq;
	evt->name = "local_timer";
	evt->features = msm_clockevent.features;
	evt->rating = msm_clockevent.rating;
	evt->set_mode = msm_timer_set_mode;
	evt->set_next_event = msm_timer_set_next_event;
	evt->shift = msm_clockevent.shift;
	evt->mult = div_sc(GPT_HZ, NSEC_PER_SEC, evt->shift);
	evt->max_delta_ns = clockevent_delta2ns(0xf0000000, evt);
	evt->min_delta_ns = clockevent_delta2ns(4, evt);

	*__this_cpu_ptr(msm_evt.percpu_evt) = evt;
	clockevents_register_device(evt);
	enable_percpu_irq(evt->irq, 0);
	return 0;
	}

	static void msm_local_timer_stop(struct clock_event_device *evt)
	{
	evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
	disable_percpu_irq(evt->irq);
	}

	static struct local_timer_ops msm_local_timer_ops __cpuinitdata = {
	.setup = msm_local_timer_setup,
	.stop = msm_local_timer_stop,
	};
	#endif /* CONFIG_LOCAL_TIMERS */

	static notrace u32 msm_sched_clock_read(void)
	{
	return msm_clocksource.read(&msm_clocksource);
	}

	static void __init msm_timer_init(void)
	{
	struct clock_event_device *ce = &msm_clockevent;
	struct clocksource *cs = &msm_clocksource;
	int res;
	u32 dgt_hz;

	if (cpu_is_msm7x01()) {
	event_base = MSM_CSR_BASE;
	source_base = MSM_CSR_BASE + 0x10;
	dgt_hz = 19200000 >> MSM_DGT_SHIFT; /* 600 KHz */
	cs->read = msm_read_timer_count_shift;
	cs->mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT));
	} else if (cpu_is_msm7x30()) {
	event_base = MSM_CSR_BASE + 0x04;
	source_base = MSM_CSR_BASE + 0x24;
	dgt_hz = 24576000 / 4;
	} else if (cpu_is_qsd8x50()) {
	event_base = MSM_CSR_BASE;
	source_base = MSM_CSR_BASE + 0x10;
	dgt_hz = 19200000 / 4;
	} else if (cpu_is_msm8x60() \|\| cpu_is_msm8960()) {
	event_base = MSM_TMR_BASE + 0x04;
	/* Use CPU0's timer as the global clock source. */
	source_base = MSM_TMR0_BASE + 0x24;
	dgt_hz = 27000000 / 4;
	writel_relaxed(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL);
	} else
	BUG();

	writel_relaxed(0, event_base + TIMER_ENABLE);
	writel_relaxed(0, event_base + TIMER_CLEAR);
	writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
	ce->cpumask = cpumask_of(0);

	ce->irq = INT_GP_TIMER_EXP;
	clockevents_config_and_register(ce, GPT_HZ, 4, 0xffffffff);
	if (cpu_is_msm8x60() \|\| cpu_is_msm8960()) {
	msm_evt.percpu_evt = alloc_percpu(struct clock_event_device *);
	if (!msm_evt.percpu_evt) {
	pr_err("memory allocation failed for %s\n", ce->name);
	goto err;
	}
	*__this_cpu_ptr(msm_evt.percpu_evt) = ce;
	res = request_percpu_irq(ce->irq, msm_timer_interrupt,
	ce->name, msm_evt.percpu_evt);
	if (!res) {
	enable_percpu_irq(ce->irq, 0);
	#ifdef CONFIG_LOCAL_TIMERS
	local_timer_register(&msm_local_timer_ops);
	#endif
	}
	} else {
	msm_evt.evt = ce;
	res = request_irq(ce->irq, msm_timer_interrupt,
	IRQF_TIMER \| IRQF_NOBALANCING \|
	IRQF_TRIGGER_RISING, ce->name, &msm_evt.evt);
	}

	if (res)
	pr_err("request_irq failed for %s\n", ce->name);
	err:
	writel_relaxed(TIMER_ENABLE_EN, source_base + TIMER_ENABLE);
	res = clocksource_register_hz(cs, dgt_hz);
	if (res)
	pr_err("clocksource_register failed\n");
	setup_sched_clock(msm_sched_clock_read,
	cpu_is_msm7x01() ? 32 - MSM_DGT_SHIFT : 32, dgt_hz);
	}

	struct sys_timer msm_timer = {
	.init = msm_timer_init
	};