Release 4.14 arch/nios2/kernel/time.c

Directory: arch/nios2/kernel
/*
 * Copyright (C) 2013-2014 Altera Corporation
 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
 * Copyright (C) 2004 Microtronix Datacom Ltd.
 *
 * 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/export.h>
#include <linux/interrupt.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/io.h>
#include <linux/slab.h>


#define ALTR_TIMER_COMPATIBLE		"altr,timer-1.0"


#define ALTERA_TIMER_STATUS_REG	0

#define ALTERA_TIMER_CONTROL_REG	4

#define ALTERA_TIMER_PERIODL_REG	8

#define ALTERA_TIMER_PERIODH_REG	12

#define ALTERA_TIMER_SNAPL_REG		16

#define ALTERA_TIMER_SNAPH_REG		20


#define ALTERA_TIMER_CONTROL_ITO_MSK	(0x1)

#define ALTERA_TIMER_CONTROL_CONT_MSK	(0x2)

#define ALTERA_TIMER_CONTROL_START_MSK	(0x4)

#define ALTERA_TIMER_CONTROL_STOP_MSK	(0x8)


struct nios2_timer {
	
void __iomem *base;
	
unsigned long freq;
};


struct nios2_clockevent_dev {
	
struct nios2_timer timer;
	
struct clock_event_device ced;
};


struct nios2_clocksource {
	
struct nios2_timer timer;
	
struct clocksource cs;
};


static inline struct nios2_clockevent_dev *
	
to_nios2_clkevent(struct clock_event_device *evt)
{
	return container_of(evt, struct nios2_clockevent_dev, ced);
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 25 100.00% 1 100.00%
Total 25 100.00% 1 100.00%


static inline struct nios2_clocksource *
	
to_nios2_clksource(struct clocksource *cs)
{
	return container_of(cs, struct nios2_clocksource, cs);
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 25 100.00% 1 100.00%
Total 25 100.00% 1 100.00%



static u16 timer_readw(struct nios2_timer *timer, u32 offs)
{
	return readw(timer->base + offs);
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 24 100.00% 1 100.00%
Total 24 100.00% 1 100.00%



static void timer_writew(struct nios2_timer *timer, u16 val, u32 offs)
{
	writew(val, timer->base + offs);
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 28 100.00% 1 100.00%
Total 28 100.00% 1 100.00%



static inline unsigned long read_timersnapshot(struct nios2_timer *timer)
{
	unsigned long count;

	timer_writew(timer, 0, ALTERA_TIMER_SNAPL_REG);
	count = timer_readw(timer, ALTERA_TIMER_SNAPH_REG) << 16 |
		timer_readw(timer, ALTERA_TIMER_SNAPL_REG);

	return count;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 47 100.00% 1 100.00%
Total 47 100.00% 1 100.00%



static u64 nios2_timer_read(struct clocksource *cs)
{
	struct nios2_clocksource *nios2_cs = to_nios2_clksource(cs);
	unsigned long flags;
	u32 count;

	local_irq_save(flags);
	count = read_timersnapshot(&nios2_cs->timer);
	local_irq_restore(flags);

	/* Counter is counting down */
	return ~count;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 52 98.11% 1 50.00%
Thomas Gleixner 1 1.89% 1 50.00%
Total 53 100.00% 2 100.00%


static struct nios2_clocksource nios2_cs = {
	.cs = {
		.name	= "nios2-clksrc",
		.rating	= 250,
		.read	= nios2_timer_read,
		.mask	= CLOCKSOURCE_MASK(32),
		.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
        },
};



cycles_t get_cycles(void)
{
	/* Only read timer if it has been initialized */
	if (nios2_cs.timer.base)
		return nios2_timer_read(&nios2_cs.cs);
	return 0;
}
Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 16 57.14% 1 50.00%
Guenter Roeck 12 42.86% 1 50.00%
Total 28 100.00% 2 100.00%


EXPORT_SYMBOL(get_cycles);



static void nios2_timer_start(struct nios2_timer *timer)
{
	u16 ctrl;

	ctrl = timer_readw(timer, ALTERA_TIMER_CONTROL_REG);
	ctrl |= ALTERA_TIMER_CONTROL_START_MSK;
	timer_writew(timer, ctrl, ALTERA_TIMER_CONTROL_REG);
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 36 100.00% 1 100.00%
Total 36 100.00% 1 100.00%



static void nios2_timer_stop(struct nios2_timer *timer)
{
	u16 ctrl;

	ctrl = timer_readw(timer, ALTERA_TIMER_CONTROL_REG);
	ctrl |= ALTERA_TIMER_CONTROL_STOP_MSK;
	timer_writew(timer, ctrl, ALTERA_TIMER_CONTROL_REG);
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 36 100.00% 1 100.00%
Total 36 100.00% 1 100.00%



static void nios2_timer_config(struct nios2_timer *timer, unsigned long period,
			       bool periodic)
{
	u16 ctrl;

	/* The timer's actual period is one cycle greater than the value
         * stored in the period register. */
	 period--;

	ctrl = timer_readw(timer, ALTERA_TIMER_CONTROL_REG);
	/* stop counter */
	timer_writew(timer, ctrl | ALTERA_TIMER_CONTROL_STOP_MSK,
		ALTERA_TIMER_CONTROL_REG);

	/* write new count */
	timer_writew(timer, period, ALTERA_TIMER_PERIODL_REG);
	timer_writew(timer, period >> 16, ALTERA_TIMER_PERIODH_REG);

	ctrl |= ALTERA_TIMER_CONTROL_START_MSK | ALTERA_TIMER_CONTROL_ITO_MSK;
	if (periodic)
		ctrl |= ALTERA_TIMER_CONTROL_CONT_MSK;
	else
		ctrl &= ~ALTERA_TIMER_CONTROL_CONT_MSK;
	timer_writew(timer, ctrl, ALTERA_TIMER_CONTROL_REG);
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 93 96.88% 1 50.00%
Viresh Kumar 3 3.12% 1 50.00%
Total 96 100.00% 2 100.00%



static int nios2_timer_set_next_event(unsigned long delta,
	struct clock_event_device *evt)
{
	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);

	nios2_timer_config(&nios2_ced->timer, delta, false);

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 33 82.50% 1 50.00%
Viresh Kumar 7 17.50% 1 50.00%
Total 40 100.00% 2 100.00%



static int nios2_timer_shutdown(struct clock_event_device *evt)
{
	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);
	struct nios2_timer *timer = &nios2_ced->timer;

	nios2_timer_stop(timer);
	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Viresh Kumar 31 79.49% 1 50.00%
Ley Foon Tan 8 20.51% 1 50.00%
Total 39 100.00% 2 100.00%



static int nios2_timer_set_periodic(struct clock_event_device *evt)
{
	unsigned long period;
	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);
	struct nios2_timer *timer = &nios2_ced->timer;

	period = DIV_ROUND_UP(timer->freq, HZ);
	nios2_timer_config(timer, period, true);
	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 51 87.93% 1 50.00%
Viresh Kumar 7 12.07% 1 50.00%
Total 58 100.00% 2 100.00%



static int nios2_timer_resume(struct clock_event_device *evt)
{
	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);
	struct nios2_timer *timer = &nios2_ced->timer;

	nios2_timer_start(timer);
	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Viresh Kumar 31 79.49% 1 50.00%
Ley Foon Tan 8 20.51% 1 50.00%
Total 39 100.00% 2 100.00%



irqreturn_t timer_interrupt(int irq, void *dev_id)
{
	struct clock_event_device *evt = (struct clock_event_device *) dev_id;
	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);

	/* Clear the interrupt condition */
	timer_writew(&nios2_ced->timer, 0, ALTERA_TIMER_STATUS_REG);
	evt->event_handler(evt);

	return IRQ_HANDLED;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 57 100.00% 1 100.00%
Total 57 100.00% 1 100.00%



static int __init nios2_timer_get_base_and_freq(struct device_node *np,
				void __iomem **base, u32 *freq)
{
	*base = of_iomap(np, 0);
	if (!*base) {
		pr_crit("Unable to map reg for %s\n", np->name);
		return -ENXIO;
	}

	if (of_property_read_u32(np, "clock-frequency", freq)) {
		pr_crit("Unable to get %s clock frequency\n", np->name);
		return -EINVAL;
	}

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 64 78.05% 1 50.00%
Daniel Lezcano 18 21.95% 1 50.00%
Total 82 100.00% 2 100.00%


static struct nios2_clockevent_dev nios2_ce = {
	.ced = {
		.name = "nios2-clkevent",
		.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
		.rating = 250,
		.shift = 32,
		.set_next_event = nios2_timer_set_next_event,
		.set_state_shutdown = nios2_timer_shutdown,
		.set_state_periodic = nios2_timer_set_periodic,
		.set_state_oneshot = nios2_timer_shutdown,
		.tick_resume = nios2_timer_resume,
        },
};



static __init int nios2_clockevent_init(struct device_node *timer)
{
	void __iomem *iobase;
	u32 freq;
	int irq, ret;

	ret = nios2_timer_get_base_and_freq(timer, &iobase, &freq);
	if (ret)
		return ret;

	irq = irq_of_parse_and_map(timer, 0);
	if (!irq) {
		pr_crit("Unable to parse timer irq\n");
		return -EINVAL;
	}

	nios2_ce.timer.base = iobase;
	nios2_ce.timer.freq = freq;

	nios2_ce.ced.cpumask = cpumask_of(0);
	nios2_ce.ced.irq = irq;

	nios2_timer_stop(&nios2_ce.timer);
	/* clear pending interrupt */
	timer_writew(&nios2_ce.timer, 0, ALTERA_TIMER_STATUS_REG);

	ret = request_irq(irq, timer_interrupt, IRQF_TIMER, timer->name,
			  &nios2_ce.ced);
	if (ret) {
		pr_crit("Unable to setup timer irq\n");
		return ret;
	}

	clockevents_config_and_register(&nios2_ce.ced, freq, 1, ULONG_MAX);

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 142 80.23% 1 33.33%
Daniel Lezcano 34 19.21% 1 33.33%
Dmitry Torokhov 1 0.56% 1 33.33%
Total 177 100.00% 3 100.00%



static __init int nios2_clocksource_init(struct device_node *timer)
{
	unsigned int ctrl;
	void __iomem *iobase;
	u32 freq;
	int ret;

	ret = nios2_timer_get_base_and_freq(timer, &iobase, &freq);
	if (ret)
		return ret;

	nios2_cs.timer.base = iobase;
	nios2_cs.timer.freq = freq;

	ret = clocksource_register_hz(&nios2_cs.cs, freq);
	if (ret)
		return ret;

	timer_writew(&nios2_cs.timer, USHRT_MAX, ALTERA_TIMER_PERIODL_REG);
	timer_writew(&nios2_cs.timer, USHRT_MAX, ALTERA_TIMER_PERIODH_REG);

	/* interrupt disable + continuous + start */
	ctrl = ALTERA_TIMER_CONTROL_CONT_MSK | ALTERA_TIMER_CONTROL_START_MSK;
	timer_writew(&nios2_cs.timer, ctrl, ALTERA_TIMER_CONTROL_REG);

	/* Calibrate the delay loop directly */
	lpj_fine = freq / HZ;

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 110 81.48% 1 50.00%
Daniel Lezcano 25 18.52% 1 50.00%
Total 135 100.00% 2 100.00%

/*
 * The first timer instance will use as a clockevent. If there are two or
 * more instances, the second one gets used as clocksource and all
 * others are unused.
*/


static int __init nios2_time_init(struct device_node *timer)
{
	static int num_called;
	int ret;

	switch (num_called) {
	case 0:
		ret = nios2_clockevent_init(timer);
		break;
	case 1:
		ret = nios2_clocksource_init(timer);
		break;
	default:
		ret = 0;
		break;
	}

	num_called++;

	return ret;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 44 74.58% 1 33.33%
Daniel Lezcano 11 18.64% 1 33.33%
Arnd Bergmann 4 6.78% 1 33.33%
Total 59 100.00% 3 100.00%



void read_persistent_clock(struct timespec *ts)
{
	ts->tv_sec = mktime(2007, 1, 1, 0, 0, 0);
	ts->tv_nsec = 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 35 100.00% 1 100.00%
Total 35 100.00% 1 100.00%



void __init time_init(void)
{
	struct device_node *np;
	int count = 0;

	for_each_compatible_node(np, NULL,  ALTR_TIMER_COMPATIBLE)
		count++;

	if (count < 2)
		panic("%d timer is found, it needs 2 timers in system\n", count);

	timer_probe();
}

Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 44 97.78% 2 66.67%
Daniel Lezcano 1 2.22% 1 33.33%
Total 45 100.00% 3 100.00%

TIMER_OF_DECLARE(nios2_timer, ALTR_TIMER_COMPATIBLE, nios2_time_init);
Overall Contributors
Person Tokens Prop Commits CommitProp
Ley Foon Tan 1181 84.78% 2 18.18%
Viresh Kumar 96 6.89% 1 9.09%
Daniel Lezcano 90 6.46% 3 27.27%
Guenter Roeck 12 0.86% 1 9.09%
Herbert Xu 8 0.57% 1 9.09%
Arnd Bergmann 4 0.29% 1 9.09%
Dmitry Torokhov 1 0.07% 1 9.09%
Thomas Gleixner 1 0.07% 1 9.09%
Total 1393 100.00% 11 100.00%
Directory: arch/nios2/kernel

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
Ley Foon Tan	25	100.00%	1	100.00%
Total	25	100.00%	1	100.00%
cregit-Linux how code gets into the kernel

Release 4.14 arch/nios2/kernel/time.c

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Overall Contributors
