Release 4.13 arch/arm/mach-omap2/timer.c

Directory: arch/arm/mach-omap2
/*
 * linux/arch/arm/mach-omap2/timer.c
 *
 * OMAP2 GP timer support.
 *
 * Copyright (C) 2009 Nokia Corporation
 *
 * Update to use new clocksource/clockevent layers
 * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
 * Copyright (C) 2007 MontaVista Software, Inc.
 *
 * Original driver:
 * Copyright (C) 2005 Nokia Corporation
 * Author: Paul Mundt <paul.mundt@nokia.com>
 *         Juha YrjÃ¶lÃ¤ <juha.yrjola@nokia.com>
 * OMAP Dual-mode timer framework support by Timo Teras
 *
 * Some parts based off of TI's 24xx code:
 *
 * Copyright (C) 2004-2009 Texas Instruments, Inc.
 *
 * Roughly modelled after the OMAP1 MPU timer code.
 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/init.h>
#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/platform_data/dmtimer-omap.h>
#include <linux/sched_clock.h>

#include <asm/mach/time.h>
#include <asm/smp_twd.h>

#include "omap_hwmod.h"
#include "omap_device.h"
#include <plat/counter-32k.h>
#include <plat/dmtimer.h>
#include "omap-pm.h"

#include "soc.h"
#include "common.h"
#include "control.h"
#include "powerdomain.h"
#include "omap-secure.h"


#define REALTIME_COUNTER_BASE				0x48243200

#define INCREMENTER_NUMERATOR_OFFSET			0x10

#define INCREMENTER_DENUMERATOR_RELOAD_OFFSET		0x14

#define NUMERATOR_DENUMERATOR_MASK			0xfffff000

/* Clockevent code */


static struct omap_dm_timer clkev;

static struct clock_event_device clockevent_gpt;

/* Clockevent hwmod for am335x and am437x suspend */

static struct omap_hwmod *clockevent_gpt_hwmod;

#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER

static unsigned long arch_timer_freq;



void set_cntfreq(void)
{
	omap_smc1(OMAP5_DRA7_MON_SET_CNTFRQ_INDEX, arch_timer_freq);
}
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#endif



static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
{
	struct clock_event_device *evt = &clockevent_gpt;

	__omap_dm_timer_write_status(&clkev, OMAP_TIMER_INT_OVERFLOW);

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

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Tony Lindgren 5 12.82% 3 75.00%
Total 39 100.00% 4 100.00%


static struct irqaction omap2_gp_timer_irq = {
	.name		= "gp_timer",
	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
	.handler	= omap2_gp_timer_interrupt,
};



static int omap2_gp_timer_set_next_event(unsigned long cycles,
					 struct clock_event_device *evt)
{
	__omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_ST,
				   0xffffffff - cycles, OMAP_TIMER_POSTED);

	return 0;
}

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Kevin Hilman 13 40.62% 1 16.67%
Timo Teräs 2 6.25% 1 16.67%
Jon Hunter 1 3.12% 1 16.67%
Total 32 100.00% 6 100.00%



static int omap2_gp_timer_shutdown(struct clock_event_device *evt)
{
	__omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
	return 0;
}

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static int omap2_gp_timer_set_periodic(struct clock_event_device *evt)
{
	u32 period;

	__omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);

	period = clkev.rate / HZ;
	period -= 1;
	/* Looks like we need to first set the load value separately */
	__omap_dm_timer_write(&clkev, OMAP_TIMER_LOAD_REG, 0xffffffff - period,
			      OMAP_TIMER_POSTED);
	__omap_dm_timer_load_start(&clkev,
				   OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
				   0xffffffff - period, OMAP_TIMER_POSTED);
	return 0;
}

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Jon Hunter 3 4.17% 1 16.67%
Total 72 100.00% 6 100.00%



static void omap_clkevt_idle(struct clock_event_device *unused)
{
	if (!clockevent_gpt_hwmod)
		return;

	omap_hwmod_idle(clockevent_gpt_hwmod);
}

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static void omap_clkevt_unidle(struct clock_event_device *unused)
{
	if (!clockevent_gpt_hwmod)
		return;

	omap_hwmod_enable(clockevent_gpt_hwmod);
	__omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
}

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static struct clock_event_device clockevent_gpt = {
	.features		= CLOCK_EVT_FEAT_PERIODIC |
				  CLOCK_EVT_FEAT_ONESHOT,
	.rating			= 300,
	.set_next_event		= omap2_gp_timer_set_next_event,
	.set_state_shutdown	= omap2_gp_timer_shutdown,
	.set_state_periodic	= omap2_gp_timer_set_periodic,
	.set_state_oneshot	= omap2_gp_timer_shutdown,
	.tick_resume		= omap2_gp_timer_shutdown,
};


static struct property device_disabled = {
	.name = "status",
	.length = sizeof("disabled"),
	.value = "disabled",
};


static const struct of_device_id omap_timer_match[] __initconst = {
	{ .compatible = "ti,omap2420-timer", },
	{ .compatible = "ti,omap3430-timer", },
	{ .compatible = "ti,omap4430-timer", },
	{ .compatible = "ti,omap5430-timer", },
	{ .compatible = "ti,dm814-timer", },
	{ .compatible = "ti,dm816-timer", },
	{ .compatible = "ti,am335x-timer", },
	{ .compatible = "ti,am335x-timer-1ms", },
	{ }
};

/**
 * omap_get_timer_dt - get a timer using device-tree
 * @match       - device-tree match structure for matching a device type
 * @property    - optional timer property to match
 *
 * Helper function to get a timer during early boot using device-tree for use
 * as kernel system timer. Optionally, the property argument can be used to
 * select a timer with a specific property. Once a timer is found then mark
 * the timer node in device-tree as disabled, to prevent the kernel from
 * registering this timer as a platform device and so no one else can use it.
 */


static struct device_node * __init omap_get_timer_dt(const struct of_device_id *match,
						     const char *property)
{
	struct device_node *np;

	for_each_matching_node(np, match) {
		if (!of_device_is_available(np))
			continue;

		if (property && !of_get_property(np, property, NULL))
			continue;

		if (!property && (of_get_property(np, "ti,timer-alwon", NULL) ||
				  of_get_property(np, "ti,timer-dsp", NULL) ||
				  of_get_property(np, "ti,timer-pwm", NULL) ||
				  of_get_property(np, "ti,timer-secure", NULL)))
			continue;

		if (!of_device_is_compatible(np, "ti,omap-counter32k"))
			of_add_property(np, &device_disabled);
		return np;
	}

	return NULL;
}

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Uwe Kleine-König 1 0.80% 1 20.00%
Total 125 100.00% 5 100.00%

/**
 * omap_dmtimer_init - initialisation function when device tree is used
 *
 * For secure OMAP3/DRA7xx devices, timers with device type "timer-secure"
 * cannot be used by the kernel as they are reserved. Therefore, to prevent the
 * kernel registering these devices remove them dynamically from the device
 * tree on boot.
 */


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

	if (!cpu_is_omap34xx() && !soc_is_dra7xx())
		return;

	/* If we are a secure device, remove any secure timer nodes */
	if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
		np = omap_get_timer_dt(omap_timer_match, "ti,timer-secure");
		of_node_put(np);
	}
}

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Total 51 100.00% 4 100.00%

/**
 * omap_dm_timer_get_errata - get errata flags for a timer
 *
 * Get the timer errata flags that are specific to the OMAP device being used.
 */


static u32 __init omap_dm_timer_get_errata(void)
{
	if (cpu_is_omap24xx())
		return 0;

	return OMAP_TIMER_ERRATA_I103_I767;
}

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static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
					 const char *fck_source,
					 const char *property,
					 const char **timer_name,
					 int posted)
{
	const char *oh_name = NULL;
	struct device_node *np;
	struct omap_hwmod *oh;
	struct clk *src;
	int r = 0;

	np = omap_get_timer_dt(omap_timer_match, property);
	if (!np)
		return -ENODEV;

	of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
	if (!oh_name)
		return -ENODEV;

	timer->irq = irq_of_parse_and_map(np, 0);
	if (!timer->irq)
		return -ENXIO;

	timer->io_base = of_iomap(np, 0);

	timer->fclk = of_clk_get_by_name(np, "fck");

	of_node_put(np);

	oh = omap_hwmod_lookup(oh_name);
	if (!oh)
		return -ENODEV;

	*timer_name = oh->name;

	if (!timer->io_base)
		return -ENXIO;

	omap_hwmod_setup_one(oh_name);

	/* After the dmtimer is using hwmod these clocks won't be needed */
	if (IS_ERR_OR_NULL(timer->fclk))
		timer->fclk = clk_get(NULL, omap_hwmod_get_main_clk(oh));
	if (IS_ERR(timer->fclk))
		return PTR_ERR(timer->fclk);

	src = clk_get(NULL, fck_source);
	if (IS_ERR(src))
		return PTR_ERR(src);

	WARN(clk_set_parent(timer->fclk, src) < 0,
	     "Cannot set timer parent clock, no PLL clock driver?");

	clk_put(src);

	omap_hwmod_enable(oh);
	__omap_dm_timer_init_regs(timer);

	if (posted)
		__omap_dm_timer_enable_posted(timer);

	/* Check that the intended posted configuration matches the actual */
	if (posted != timer->posted)
		return -EINVAL;

	timer->rate = clk_get_rate(timer->fclk);
	timer->reserved = 1;

	return r;
}

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Tony Lindgren 125 38.94% 4 17.39%
Paul Walmsley 15 4.67% 3 13.04%
Tero Kristo 12 3.74% 2 8.70%
Tarun Kanti DebBarma 4 1.25% 1 4.35%
Timo Teräs 2 0.62% 1 4.35%
Russell King 2 0.62% 1 4.35%
Afzal Mohammed 2 0.62% 1 4.35%
Kevin Hilman 1 0.31% 1 4.35%
Total 321 100.00% 23 100.00%

#if !defined(CONFIG_SMP) && defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)


void tick_broadcast(const struct cpumask *mask)
{
}
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#endif



static void __init omap2_gp_clockevent_init(int gptimer_id,
						const char *fck_source,
						const char *property)
{
	int res;

	clkev.id = gptimer_id;
	clkev.errata = omap_dm_timer_get_errata();

	/*
         * For clock-event timers we never read the timer counter and
         * so we are not impacted by errata i103 and i767. Therefore,
         * we can safely ignore this errata for clock-event timers.
         */
	__omap_dm_timer_override_errata(&clkev, OMAP_TIMER_ERRATA_I103_I767);

	res = omap_dm_timer_init_one(&clkev, fck_source, property,
				     &clockevent_gpt.name, OMAP_TIMER_POSTED);
	BUG_ON(res);

	omap2_gp_timer_irq.dev_id = &clkev;
	setup_irq(clkev.irq, &omap2_gp_timer_irq);

	__omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);

	clockevent_gpt.cpumask = cpu_possible_mask;
	clockevent_gpt.irq = omap_dm_timer_get_irq(&clkev);
	clockevents_config_and_register(&clockevent_gpt, clkev.rate,
					3, /* Timer internal resynch latency */
					0xffffffff);

	if (soc_is_am33xx() || soc_is_am43xx()) {
		clockevent_gpt.suspend = omap_clkevt_idle;
		clockevent_gpt.resume = omap_clkevt_unidle;

		clockevent_gpt_hwmod =
			omap_hwmod_lookup(clockevent_gpt.name);
	}

	pr_info("OMAP clockevent source: %s at %lu Hz\n", clockevent_gpt.name,
		clkev.rate);
}

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Jon Hunter 40 23.67% 4 28.57%
Dave Gerlach 31 18.34% 1 7.14%
Kevin Hilman 22 13.02% 1 7.14%
Shawn Guo 10 5.92% 1 7.14%
Santosh Shilimkar 9 5.33% 1 7.14%
Paul Walmsley 4 2.37% 1 7.14%
Timo Teräs 1 0.59% 1 7.14%
Total 169 100.00% 14 100.00%

/* Clocksource code */

static struct omap_dm_timer clksrc;

static bool use_gptimer_clksrc __initdata;

/*
 * clocksource
 */


static u64 clocksource_read_cycles(struct clocksource *cs)
{
	return (u64)__omap_dm_timer_read_counter(&clksrc,
						     OMAP_TIMER_NONPOSTED);
}

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Tony Lindgren 4 17.39% 2 33.33%
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Jon Hunter 1 4.35% 1 16.67%
Total 23 100.00% 6 100.00%


static struct clocksource clocksource_gpt = {
	.rating		= 300,
	.read		= clocksource_read_cycles,
	.mask		= CLOCKSOURCE_MASK(32),
	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
};



static u64 notrace dmtimer_read_sched_clock(void)
{
	if (clksrc.reserved)
		return __omap_dm_timer_read_counter(&clksrc,
						    OMAP_TIMER_NONPOSTED);

	return 0;
}

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Marc Zyngier 3 11.11% 1 16.67%
Paul Walmsley 1 3.70% 1 16.67%
Jon Hunter 1 3.70% 1 16.67%
Vaibhav Hiremath 1 3.70% 1 16.67%
Stephen Boyd 1 3.70% 1 16.67%
Total 27 100.00% 6 100.00%


static const struct of_device_id omap_counter_match[] __initconst = {
	{ .compatible = "ti,omap-counter32k", },
	{ }
};

/* Setup free-running counter for clocksource */


static int __init __maybe_unused omap2_sync32k_clocksource_init(void)
{
	int ret;
	struct device_node *np = NULL;
	struct omap_hwmod *oh;
	const char *oh_name = "counter_32k";

	/*
         * See if the 32kHz counter is supported.
         */
	np = omap_get_timer_dt(omap_counter_match, NULL);
	if (!np)
		return -ENODEV;

	of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
	if (!oh_name)
		return -ENODEV;

	/*
         * First check hwmod data is available for sync32k counter
         */
	oh = omap_hwmod_lookup(oh_name);
	if (!oh || oh->slaves_cnt == 0)
		return -ENODEV;

	omap_hwmod_setup_one(oh_name);

	ret = omap_hwmod_enable(oh);
	if (ret) {
		pr_warn("%s: failed to enable counter_32k module (%d)\n",
							__func__, ret);
		return ret;
	}

	return ret;
}

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Tony Lindgren 1 0.78% 1 25.00%
Total 128 100.00% 4 100.00%



static void __init omap2_gptimer_clocksource_init(int gptimer_id,
						  const char *fck_source,
						  const char *property)
{
	int res;

	clksrc.id = gptimer_id;
	clksrc.errata = omap_dm_timer_get_errata();

	res = omap_dm_timer_init_one(&clksrc, fck_source, property,
				     &clocksource_gpt.name,
				     OMAP_TIMER_NONPOSTED);
	BUG_ON(res);

	__omap_dm_timer_load_start(&clksrc,
				   OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0,
				   OMAP_TIMER_NONPOSTED);
	sched_clock_register(dmtimer_read_sched_clock, 32, clksrc.rate);

	if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
		pr_err("Could not register clocksource %s\n",
			clocksource_gpt.name);
	else
		pr_info("OMAP clocksource: %s at %lu Hz\n",
			clocksource_gpt.name, clksrc.rate);
}

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Jon Hunter 32 26.67% 5 33.33%
Kevin Hilman 32 26.67% 1 6.67%
Vaibhav Hiremath 11 9.17% 1 6.67%
Paul Walmsley 6 5.00% 1 6.67%
Russell King 2 1.67% 1 6.67%
Hemant Pedanekar 2 1.67% 1 6.67%
Stephen Boyd 1 0.83% 1 6.67%
Marc Zyngier 1 0.83% 1 6.67%
Total 120 100.00% 15 100.00%



static void __init __omap_sync32k_timer_init(int clkev_nr, const char *clkev_src,
		const char *clkev_prop, int clksrc_nr, const char *clksrc_src,
		const char *clksrc_prop, bool gptimer)
{
	omap_clk_init();
	omap_dmtimer_init();
	omap2_gp_clockevent_init(clkev_nr, clkev_src, clkev_prop);

	/* Enable the use of clocksource="gp_timer" kernel parameter */
	if (use_gptimer_clksrc || gptimer)
		omap2_gptimer_clocksource_init(clksrc_nr, clksrc_src,
						clksrc_prop);
	else
		omap2_sync32k_clocksource_init();
}

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Felipe Balbi 52 73.24% 1 50.00%
Santosh Shilimkar 19 26.76% 1 50.00%
Total 71 100.00% 2 100.00%



void __init omap_init_time(void)
{
	__omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
			2, "timer_sys_ck", NULL, false);

	timer_probe();
}

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Felipe Balbi 21 75.00% 3 60.00%
Santosh Shilimkar 6 21.43% 1 20.00%
Daniel Lezcano 1 3.57% 1 20.00%
Total 28 100.00% 5 100.00%

#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM43XX)


void __init omap3_secure_sync32k_timer_init(void)
{
	__omap_sync32k_timer_init(12, "secure_32k_fck", "ti,timer-secure",
			2, "timer_sys_ck", NULL, false);

	timer_probe();
}
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Felipe Balbi 19 67.86% 1 20.00%
Lennart Sorensen 4 14.29% 1 20.00%
Tero Kristo 2 7.14% 1 20.00%
Santosh Shilimkar 2 7.14% 1 20.00%
Daniel Lezcano 1 3.57% 1 20.00%
Total 28 100.00% 5 100.00%

#endif /* CONFIG_ARCH_OMAP3 */

#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX) || \
	defined(CONFIG_SOC_AM43XX)


void __init omap3_gptimer_timer_init(void)
{
	__omap_sync32k_timer_init(2, "timer_sys_ck", NULL,
			1, "timer_sys_ck", "ti,timer-alwon", true);
	if (of_have_populated_dt())
		timer_probe();
}
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Grygorii Strashko 5 15.15% 1 16.67%
Santosh Shilimkar 3 9.09% 1 16.67%
Lennart Sorensen 2 6.06% 1 16.67%
Tero Kristo 2 6.06% 1 16.67%
Daniel Lezcano 1 3.03% 1 16.67%
Total 33 100.00% 6 100.00%

#endif

#if defined(CONFIG_ARCH_OMAP4) || defined(CONFIG_SOC_OMAP5) ||		\
	defined(CONFIG_SOC_DRA7XX)


static void __init omap4_sync32k_timer_init(void)
{
	__omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
			2, "sys_clkin_ck", NULL, false);
}

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Tony Lindgren 7 26.92% 3 33.33%
Felipe Balbi 7 26.92% 1 11.11%
Santosh Shilimkar 6 23.08% 1 11.11%
Jon Hunter 5 19.23% 3 33.33%
Igor Grinberg 1 3.85% 1 11.11%
Total 26 100.00% 9 100.00%



void __init omap4_local_timer_init(void)
{
	omap4_sync32k_timer_init();
	timer_probe();
}
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Daniel Lezcano 1 7.14% 1 50.00%
Total 14 100.00% 2 100.00%

#endif

#if defined(CONFIG_SOC_OMAP5) || defined(CONFIG_SOC_DRA7XX)

/*
 * The realtime counter also called master counter, is a free-running
 * counter, which is related to real time. It produces the count used
 * by the CPU local timer peripherals in the MPU cluster. The timer counts
 * at a rate of 6.144 MHz. Because the device operates on different clocks
 * in different power modes, the master counter shifts operation between
 * clocks, adjusting the increment per clock in hardware accordingly to
 * maintain a constant count rate.
 */


static void __init realtime_counter_init(void)
{
#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
	void __iomem *base;
	static struct clk *sys_clk;
	unsigned long rate;
	unsigned int reg;
	unsigned long long num, den;

	base = ioremap(REALTIME_COUNTER_BASE, SZ_32);
	if (!base) {
		pr_err("%s: ioremap failed\n", __func__);
		return;
	}
	sys_clk = clk_get(NULL, "sys_clkin");
	if (IS_ERR(sys_clk)) {
		pr_err("%s: failed to get system clock handle\n", __func__);
		iounmap(base);
		return;
	}

	rate = clk_get_rate(sys_clk);

	if (soc_is_dra7xx()) {
		/*
                 * Errata i856 says the 32.768KHz crystal does not start at
                 * power on, so the CPU falls back to an emulated 32KHz clock
                 * based on sysclk / 610 instead. This causes the master counter
                 * frequency to not be 6.144MHz but at sysclk / 610 * 375 / 2
                 * (OR sysclk * 75 / 244)
                 *
                 * This affects at least the DRA7/AM572x 1.0, 1.1 revisions.
                 * Of course any board built without a populated 32.768KHz
                 * crystal would also need this fix even if the CPU is fixed
                 * later.
                 *
                 * Either case can be detected by using the two speedselect bits
                 * If they are not 0, then the 32.768KHz clock driving the
                 * coarse counter that corrects the fine counter every time it
                 * ticks is actually rate/610 rather than 32.768KHz and we
                 * should compensate to avoid the 570ppm (at 20MHz, much worse
                 * at other rates) too fast system time.
                 */
		reg = omap_ctrl_readl(DRA7_CTRL_CORE_BOOTSTRAP);
		if (reg & DRA7_SPEEDSELECT_MASK) {
			num = 75;
			den = 244;
			goto sysclk1_based;
		}
	}

	/* Numerator/denumerator values refer TRM Realtime Counter section */
	switch (rate) {
	case 12000000:
		num = 64;
		den = 125;
		break;
	case 13000000:
		num = 768;
		den = 1625;
		break;
	case 19200000:
		num = 8;
		den = 25;
		break;
	case 20000000:
		num = 192;
		den = 625;
		break;
	case 26000000:
		num = 384;
		den = 1625;
		break;
	case 27000000:
		num = 256;
		den = 1125;
		break;
	case 38400000:
	default:
		/* Program it for 38.4 MHz */
		num = 4;
		den = 25;
		break;
	}

sysclk1_based:
	/* Program numerator and denumerator registers */
	reg = readl_relaxed(base + INCREMENTER_NUMERATOR_OFFSET) &
			NUMERATOR_DENUMERATOR_MASK;
	reg |= num;
	writel_relaxed(reg, base + INCREMENTER_NUMERATOR_OFFSET);

	reg = readl_relaxed(base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET) &
			NUMERATOR_DENUMERATOR_MASK;
	reg |= den;
	writel_relaxed(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET);

	arch_timer_freq = DIV_ROUND_UP_ULL(rate * num, den);
	set_cntfreq();

	iounmap(base);
#endif
}

Contributors
Person Tokens Prop Commits CommitProp
Santosh Shilimkar 122 40.80% 2 9.52%
Felipe Balbi 106 35.45% 2 9.52%
R Sricharan 22 7.36% 3 14.29%
Lennart Sorensen 12 4.01% 2 9.52%
Igor Grinberg 10 3.34% 2 9.52%
Jon Hunter 7 2.34% 2 9.52%
Simon Barth 4 1.34% 1 4.76%
Victor Kamensky 4 1.34% 1 4.76%
Afzal Mohammed 3 1.00% 1 4.76%
Tony Lindgren 3 1.00% 1 4.76%
Rajendra Nayak 2 0.67% 1 4.76%
Kevin Hilman 2 0.67% 1 4.76%
Marc Zyngier 1 0.33% 1 4.76%
Chen Baozi 1 0.33% 1 4.76%
Total 299 100.00% 21 100.00%



void __init omap5_realtime_timer_init(void)
{
	omap4_sync32k_timer_init();
	realtime_counter_init();

	timer_probe();
}
Contributors
Person Tokens Prop Commits CommitProp
Santosh Shilimkar 13 76.47% 2 40.00%
Igor Grinberg 2 11.76% 1 20.00%
Jon Hunter 1 5.88% 1 20.00%
Daniel Lezcano 1 5.88% 1 20.00%
Total 17 100.00% 5 100.00%

#endif /* CONFIG_SOC_OMAP5 || CONFIG_SOC_DRA7XX */

/**
 * omap2_override_clocksource - clocksource override with user configuration
 *
 * Allows user to override default clocksource, using kernel parameter
 *   clocksource="gp_timer"     (For all OMAP2PLUS architectures)
 *
 * Note that, here we are using same standard kernel parameter "clocksource=",
 * and not introducing any OMAP specific interface.
 */


static int __init omap2_override_clocksource(char *str)
{
	if (!str)
		return 0;
	/*
         * For OMAP architecture, we only have two options
         *    - sync_32k (default)
         *    - gp_timer (sys_clk based)
         */
	if (!strcmp(str, "gp_timer"))
		use_gptimer_clksrc = true;

	return 0;
}
Contributors
Person Tokens Prop Commits CommitProp
Vaibhav Hiremath 37 100.00% 1 100.00%
Total 37 100.00% 1 100.00%

early_param("clocksource", omap2_override_clocksource);
Overall Contributors
Person Tokens Prop Commits CommitProp
Jon Hunter 582 26.15% 19 19.00%
Tony Lindgren 380 17.07% 17 17.00%
Felipe Balbi 281 12.62% 5 5.00%
Santosh Shilimkar 218 9.79% 5 5.00%
Kevin Hilman 215 9.66% 1 1.00%
Vaibhav Hiremath 144 6.47% 4 4.00%
Dave Gerlach 90 4.04% 1 1.00%
Viresh Kumar 48 2.16% 1 1.00%
R Sricharan 46 2.07% 4 4.00%
Grygorii Strashko 35 1.57% 2 2.00%
Paul Walmsley 33 1.48% 5 5.00%
Lennart Sorensen 23 1.03% 2 2.00%
Tero Kristo 16 0.72% 3 3.00%
Tarun Kanti DebBarma 14 0.63% 3 3.00%
Afzal Mohammed 14 0.63% 3 3.00%
Igor Grinberg 13 0.58% 2 2.00%
Shawn Guo 10 0.45% 1 1.00%
Timo Teräs 7 0.31% 1 1.00%
Daniel Lezcano 5 0.22% 1 1.00%
Suman Anna 5 0.22% 1 1.00%
Simon Barth 5 0.22% 1 1.00%
Stephen Boyd 5 0.22% 2 2.00%
Uwe Kleine-König 5 0.22% 1 1.00%
Marc Zyngier 5 0.22% 2 2.00%
Russell King 5 0.22% 3 3.00%
Magnus Damm 4 0.18% 1 1.00%
Victor Kamensky 4 0.18% 1 1.00%
Dirk Behme 3 0.13% 1 1.00%
Thomas Gleixner 2 0.09% 1 1.00%
Manjunath Kondaiah G 2 0.09% 1 1.00%
Hemant Pedanekar 2 0.09% 1 1.00%
Rajendra Nayak 2 0.09% 1 1.00%
Oussama Ghorbel 1 0.04% 1 1.00%
Chen Baozi 1 0.04% 1 1.00%
Peter Ujfalusi 1 0.04% 1 1.00%
Total 2226 100.00% 100 100.00%
Directory: arch/arm/mach-omap2

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.
Person	Tokens	Prop	Commits	CommitProp
R Sricharan	14	100.00%	1	100.00%
Total	14	100.00%	1	100.00%
cregit-Linux how code gets into the kernel

Release 4.13 arch/arm/mach-omap2/timer.c

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