Commit e8cbce97 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'timer' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc 

timer changes for msm

A very simple series. We used to have more churn in the timer
area, so this is kept separate. Will probably put this into the
drivers series next time.

* tag 'timer' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  msm: timer: Use clockevents_config_and_register()
  msm: timer: Setup interrupt after registering clockevent
  msm: timer: Remove SoC specific #ifdefs
  msm: timer: Remove msm_clocks[] and simplify code
  msm: timer: Fix ONESHOT mode interrupts
  msm: timer: Use GPT for clockevents and DGT for clocksource
  msm: timer: Cleanup #includes and #defines
  msm: timer: Tighten #ifdef for local timer support
parents b3c37522 27fdb577

arch/arm/mach-msm/timer.c

+124 −223
Original line number Diff line number Diff line 
/* linux/arch/arm/mach-msm/timer.c

/*

 *

 * 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
@@ -13,306 +14,207 @@ 
 *

 */



#include <linux/clocksource.h>

#include <linux/clockchips.h>

#include <linux/init.h>

#include <linux/time.h>

#include <linux/interrupt.h>

#include <linux/irq.h>

#include <linux/clk.h>

#include <linux/clockchips.h>

#include <linux/delay.h>

#include <linux/io.h>



#include <asm/mach/time.h>

#include <asm/hardware/gic.h>

#include <asm/localtimer.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    2

#define TIMER_ENABLE_EN                 1

#define TIMER_ENABLE_CLR_ON_MATCH_EN    BIT(1)

#define TIMER_ENABLE_EN                 BIT(0)

#define TIMER_CLEAR             0x000C

#define DGT_CLK_CTL             0x0034

enum {

	DGT_CLK_CTL_DIV_1 = 0,

	DGT_CLK_CTL_DIV_2 = 1,

	DGT_CLK_CTL_DIV_3 = 2,

	DGT_CLK_CTL_DIV_4 = 3,

};

#define CSR_PROTECTION          0x0020

#define CSR_PROTECTION_EN               1

#define DGT_CLK_CTL_DIV_4	0x3



#define GPT_HZ 32768



enum timer_location {

	LOCAL_TIMER = 0,

	GLOBAL_TIMER = 1,

};



#define MSM_GLOBAL_TIMER MSM_CLOCK_DGT



/* TODO: Remove these ifdefs */

#if defined(CONFIG_ARCH_QSD8X50)

#define DGT_HZ (19200000 / 4) /* 19.2 MHz / 4 by default */

#define MSM_DGT_SHIFT (0)

#elif defined(CONFIG_ARCH_MSM7X30)

#define DGT_HZ (24576000 / 4) /* 24.576 MHz (LPXO) / 4 by default */

#define MSM_DGT_SHIFT (0)

#elif defined(CONFIG_ARCH_MSM8X60) || defined(CONFIG_ARCH_MSM8960)

#define DGT_HZ (27000000 / 4) /* 27 MHz (PXO) / 4 by default */

#define MSM_DGT_SHIFT (0)

#else

#define DGT_HZ 19200000 /* 19.2 MHz or 600 KHz after shift */

#define MSM_DGT_SHIFT (5)

#endif



struct msm_clock {

	struct clock_event_device   clockevent;

	struct clocksource          clocksource;

	unsigned int		    irq;

	void __iomem                *regbase;

	uint32_t                    freq;

	uint32_t                    shift;

	void __iomem                *global_counter;

	void __iomem                *local_counter;

	union {

		struct clock_event_device		*evt;

		struct clock_event_device __percpu	**percpu_evt;

	};		

};



enum {

	MSM_CLOCK_GPT,

	MSM_CLOCK_DGT,

	NR_TIMERS,

};



#define MSM_DGT_SHIFT 5



static struct msm_clock msm_clocks[];

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;

	if (evt->event_handler == NULL)

		return IRQ_HANDLED;

	/* 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 cycle_t msm_read_timer_count(struct clocksource *cs)

{

	struct msm_clock *clk = container_of(cs, struct msm_clock, clocksource);



	/*

	 * Shift timer count down by a constant due to unreliable lower bits

	 * on some targets.

	 */

	return readl(clk->global_counter) >> clk->shift;

}



static struct msm_clock *clockevent_to_clock(struct clock_event_device *evt)

{

#ifdef CONFIG_SMP

	int i;

	for (i = 0; i < NR_TIMERS; i++)

		if (evt == &(msm_clocks[i].clockevent))

			return &msm_clocks[i];

	return &msm_clocks[MSM_GLOBAL_TIMER];

#else

	return container_of(evt, struct msm_clock, clockevent);

#endif

}



static int msm_timer_set_next_event(unsigned long cycles,

				    struct clock_event_device *evt)

{

	struct msm_clock *clock = clockevent_to_clock(evt);

	uint32_t now = readl(clock->local_counter);

	uint32_t alarm = now + (cycles << clock->shift);

	u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);



	writel(alarm, clock->regbase + TIMER_MATCH_VAL);

	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)

{

	struct msm_clock *clock = clockevent_to_clock(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:

		writel(TIMER_ENABLE_EN, clock->regbase + TIMER_ENABLE);

		/* Timer is enabled in set_next_event */

		break;

	case CLOCK_EVT_MODE_UNUSED:

	case CLOCK_EVT_MODE_SHUTDOWN:

		writel(0, clock->regbase + TIMER_ENABLE);

		break;

	}

	writel_relaxed(ctrl, event_base + TIMER_ENABLE);

}



static struct msm_clock msm_clocks[] = {

	[MSM_CLOCK_GPT] = {

		.clockevent = {

static struct clock_event_device msm_clockevent = {

	.name		= "gp_timer",

	.features	= CLOCK_EVT_FEAT_ONESHOT,

			.shift          = 32,

	.rating		= 200,

	.set_next_event	= msm_timer_set_next_event,

	.set_mode	= msm_timer_set_mode,

		},

		.clocksource = {

			.name           = "gp_timer",

			.rating         = 200,

			.read           = msm_read_timer_count,

			.mask           = CLOCKSOURCE_MASK(32),

			.flags          = CLOCK_SOURCE_IS_CONTINUOUS,

		},

		.irq = INT_GP_TIMER_EXP,

		.freq = GPT_HZ,

	},

	[MSM_CLOCK_DGT] = {

		.clockevent = {

			.name           = "dg_timer",

			.features       = CLOCK_EVT_FEAT_ONESHOT,

			.shift          = 32 + MSM_DGT_SHIFT,

			.rating         = 300,

			.set_next_event = msm_timer_set_next_event,

			.set_mode       = msm_timer_set_mode,

		},

		.clocksource = {

};



static union {

	struct clock_event_device *evt;

	struct clock_event_device __percpu **percpu_evt;

} msm_evt;



static void __iomem *source_base;



static cycle_t msm_read_timer_count(struct clocksource *cs)

{

	return readl_relaxed(source_base + TIMER_COUNT_VAL);

}



static 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 - MSM_DGT_SHIFT)),

	.mask	= CLOCKSOURCE_MASK(32),

	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,

		},

		.irq = INT_DEBUG_TIMER_EXP,

		.freq = DGT_HZ >> MSM_DGT_SHIFT,

		.shift = MSM_DGT_SHIFT,

	}

};



static void __init msm_timer_init(void)

{

	int i;

	struct clock_event_device *ce = &msm_clockevent;

	struct clocksource *cs = &msm_clocksource;

	int res;

	int global_offset = 0;

	u32 dgt_hz;



	if (cpu_is_msm7x01()) {

		msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE;

		msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x10;

		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()) {

		msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE + 0x04;

		msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x24;

		event_base = MSM_CSR_BASE + 0x04;

		source_base = MSM_CSR_BASE + 0x24;

		dgt_hz = 24576000 / 4;

	} else if (cpu_is_qsd8x50()) {

		msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE;

		msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x10;

		event_base = MSM_CSR_BASE;

		source_base = MSM_CSR_BASE + 0x10;

		dgt_hz = 19200000 / 4;

	} else if (cpu_is_msm8x60() || cpu_is_msm8960()) {

		msm_clocks[MSM_CLOCK_GPT].regbase = MSM_TMR_BASE + 0x04;

		msm_clocks[MSM_CLOCK_DGT].regbase = MSM_TMR_BASE + 0x24;



		/* Use CPU0's timer as the global timer. */

		global_offset = MSM_TMR0_BASE - MSM_TMR_BASE;

		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();



#ifdef CONFIG_ARCH_MSM_SCORPIONMP

	writel(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL);

#endif



	for (i = 0; i < ARRAY_SIZE(msm_clocks); i++) {

		struct msm_clock *clock = &msm_clocks[i];

		struct clock_event_device *ce = &clock->clockevent;

		struct clocksource *cs = &clock->clocksource;



		clock->local_counter = clock->regbase + TIMER_COUNT_VAL;

		clock->global_counter = clock->local_counter + global_offset;



		writel(0, clock->regbase + TIMER_ENABLE);

		writel(0, clock->regbase + TIMER_CLEAR);

		writel(~0, clock->regbase + TIMER_MATCH_VAL);



		ce->mult = div_sc(clock->freq, NSEC_PER_SEC, ce->shift);

		/* allow at least 10 seconds to notice that the timer wrapped */

		ce->max_delta_ns =

			clockevent_delta2ns(0xf0000000 >> clock->shift, ce);

		/* 4 gets rounded down to 3 */

		ce->min_delta_ns = clockevent_delta2ns(4, ce);

	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);



		res = clocksource_register_hz(cs, clock->freq);

		if (res)

			printk(KERN_ERR "msm_timer_init: clocksource_register "

			       "failed for %s\n", cs->name);



		ce->irq = clock->irq;

	ce->irq = INT_GP_TIMER_EXP;

	clockevents_config_and_register(ce, GPT_HZ, 4, 0xffffffff);

	if (cpu_is_msm8x60() || cpu_is_msm8960()) {

			clock->percpu_evt = alloc_percpu(struct clock_event_device *);

			if (!clock->percpu_evt) {

				pr_err("msm_timer_init: memory allocation "

				       "failed for %s\n", ce->name);

				continue;

		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(clock->percpu_evt) = ce;

		*__this_cpu_ptr(msm_evt.percpu_evt) = ce;

		res = request_percpu_irq(ce->irq, msm_timer_interrupt,

						 ce->name, clock->percpu_evt);

					 ce->name, msm_evt.percpu_evt);

		if (!res)

			enable_percpu_irq(ce->irq, 0);

	} else {

			clock->evt = ce;

		msm_evt.evt = ce;

		res = request_irq(ce->irq, msm_timer_interrupt,

					  IRQF_TIMER | IRQF_NOBALANCING | IRQF_TRIGGER_RISING,

					  ce->name, &clock->evt);

				  IRQF_TIMER | IRQF_NOBALANCING |

				  IRQF_TRIGGER_RISING, ce->name, &msm_evt.evt);

	}



	if (res)

			pr_err("msm_timer_init: request_irq failed for %s\n",

			       ce->name);



		clockevents_register_device(ce);

	}

		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");

}



#ifdef CONFIG_SMP

#ifdef CONFIG_LOCAL_TIMERS

int __cpuinit local_timer_setup(struct clock_event_device *evt)

{

	static bool local_timer_inited;

	struct msm_clock *clock = &msm_clocks[MSM_GLOBAL_TIMER];



	/* Use existing clock_event for cpu 0 */

	if (!smp_processor_id())

		return 0;



	writel(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL);



	if (!local_timer_inited) {

		writel(0, clock->regbase  + TIMER_ENABLE);

		writel(0, clock->regbase + TIMER_CLEAR);

		writel(~0, clock->regbase + TIMER_MATCH_VAL);

		local_timer_inited = true;

	}

	evt->irq = clock->irq;

	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 = CLOCK_EVT_FEAT_ONESHOT;

	evt->rating = clock->clockevent.rating;

	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 = clock->clockevent.shift;

	evt->mult = div_sc(clock->freq, NSEC_PER_SEC, evt->shift);

	evt->max_delta_ns =

		clockevent_delta2ns(0xf0000000 >> clock->shift, evt);

	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(clock->percpu_evt) = evt;

	enable_percpu_irq(evt->irq, 0);



	*__this_cpu_ptr(msm_evt.percpu_evt) = evt;

	clockevents_register_device(evt);

	enable_percpu_irq(evt->irq, 0);

	return 0;

}
@@ -321,8 +223,7 @@ void local_timer_stop(struct clock_event_device *evt) 
	evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);

	disable_percpu_irq(evt->irq);

}



#endif

#endif /* CONFIG_LOCAL_TIMERS */



struct sys_timer msm_timer = {

	.init = msm_timer_init

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