Release 4.12 drivers/clocksource/zevio-timer.c

Directory: drivers/clocksource
/*
 *  linux/drivers/clocksource/zevio-timer.c
 *
 *  Copyright (C) 2013 Daniel Tang <tangrs@tangrs.id.au>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2, as
 * published by the Free Software Foundation.
 *
 */

#include <linux/io.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/cpumask.h>
#include <linux/interrupt.h>
#include <linux/slab.h>


#define IO_CURRENT_VAL	0x00

#define IO_DIVIDER	0x04

#define IO_CONTROL	0x08


#define IO_TIMER1	0x00

#define IO_TIMER2	0x0C


#define IO_MATCH_BEGIN	0x18

#define IO_MATCH(x)	(IO_MATCH_BEGIN + ((x) << 2))


#define IO_INTR_STS	0x00

#define IO_INTR_ACK	0x00

#define IO_INTR_MSK	0x04


#define CNTL_STOP_TIMER	(1 << 4)

#define CNTL_RUN_TIMER	(0 << 4)


#define CNTL_INC	(1 << 3)

#define CNTL_DEC	(0 << 3)


#define CNTL_TOZERO	0

#define CNTL_MATCH(x)	((x) + 1)

#define CNTL_FOREVER	7

/* There are 6 match registers but we only use one. */

#define TIMER_MATCH	0


#define TIMER_INTR_MSK	(1 << (TIMER_MATCH))

#define TIMER_INTR_ALL	0x3F


struct zevio_timer {
	
void __iomem *base;
	

void __iomem *timer1, *timer2;
	
void __iomem *interrupt_regs;

	
struct clk *clk;
	
struct clock_event_device clkevt;
	
struct irqaction clkevt_irq;

	
char clocksource_name[64];
	
char clockevent_name[64];
};



static int zevio_timer_set_event(unsigned long delta,
				 struct clock_event_device *dev)
{
	struct zevio_timer *timer = container_of(dev, struct zevio_timer,
						 clkevt);

	writel(delta, timer->timer1 + IO_CURRENT_VAL);
	writel(CNTL_RUN_TIMER | CNTL_DEC | CNTL_MATCH(TIMER_MATCH),
			timer->timer1 + IO_CONTROL);

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Daniel Tang 62 100.00% 1 100.00%
Total 62 100.00% 1 100.00%



static int zevio_timer_shutdown(struct clock_event_device *dev)
{
	struct zevio_timer *timer = container_of(dev, struct zevio_timer,
						 clkevt);

	/* Disable timer interrupts */
	writel(0, timer->interrupt_regs + IO_INTR_MSK);
	writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK);
	/* Stop timer */
	writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL);
	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Daniel Tang 52 81.25% 1 50.00%
Viresh Kumar 12 18.75% 1 50.00%
Total 64 100.00% 2 100.00%



static int zevio_timer_set_oneshot(struct clock_event_device *dev)
{
	struct zevio_timer *timer = container_of(dev, struct zevio_timer,
						 clkevt);

	/* Enable timer interrupts */
	writel(TIMER_INTR_MSK, timer->interrupt_regs + IO_INTR_MSK);
	writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK);
	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Viresh Kumar 34 65.38% 1 50.00%
Daniel Tang 18 34.62% 1 50.00%
Total 52 100.00% 2 100.00%



static irqreturn_t zevio_timer_interrupt(int irq, void *dev_id)
{
	struct zevio_timer *timer = dev_id;
	u32 intr;

	intr = readl(timer->interrupt_regs + IO_INTR_ACK);
	if (!(intr & TIMER_INTR_MSK))
		return IRQ_NONE;

	writel(TIMER_INTR_MSK, timer->interrupt_regs + IO_INTR_ACK);
	writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL);

	if (timer->clkevt.event_handler)
		timer->clkevt.event_handler(&timer->clkevt);

	return IRQ_HANDLED;
}

Contributors
Person Tokens Prop Commits CommitProp
Daniel Tang 91 100.00% 1 100.00%
Total 91 100.00% 1 100.00%



static int __init zevio_timer_add(struct device_node *node)
{
	struct zevio_timer *timer;
	struct resource res;
	int irqnr, ret;

	timer = kzalloc(sizeof(*timer), GFP_KERNEL);
	if (!timer)
		return -ENOMEM;

	timer->base = of_iomap(node, 0);
	if (!timer->base) {
		ret = -EINVAL;
		goto error_free;
	}
	timer->timer1 = timer->base + IO_TIMER1;
	timer->timer2 = timer->base + IO_TIMER2;

	timer->clk = of_clk_get(node, 0);
	if (IS_ERR(timer->clk)) {
		ret = PTR_ERR(timer->clk);
		pr_err("Timer clock not found! (error %d)\n", ret);
		goto error_unmap;
	}

	timer->interrupt_regs = of_iomap(node, 1);
	irqnr = irq_of_parse_and_map(node, 0);

	of_address_to_resource(node, 0, &res);
	scnprintf(timer->clocksource_name, sizeof(timer->clocksource_name),
			"%llx.%s_clocksource",
			(unsigned long long)res.start, node->name);

	scnprintf(timer->clockevent_name, sizeof(timer->clockevent_name),
			"%llx.%s_clockevent",
			(unsigned long long)res.start, node->name);

	if (timer->interrupt_regs && irqnr) {
		timer->clkevt.name		= timer->clockevent_name;
		timer->clkevt.set_next_event	= zevio_timer_set_event;
		timer->clkevt.set_state_shutdown = zevio_timer_shutdown;
		timer->clkevt.set_state_oneshot = zevio_timer_set_oneshot;
		timer->clkevt.tick_resume	= zevio_timer_set_oneshot;
		timer->clkevt.rating		= 200;
		timer->clkevt.cpumask		= cpu_all_mask;
		timer->clkevt.features		= CLOCK_EVT_FEAT_ONESHOT;
		timer->clkevt.irq		= irqnr;

		writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL);
		writel(0, timer->timer1 + IO_DIVIDER);

		/* Start with timer interrupts disabled */
		writel(0, timer->interrupt_regs + IO_INTR_MSK);
		writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK);

		/* Interrupt to occur when timer value matches 0 */
		writel(0, timer->base + IO_MATCH(TIMER_MATCH));

		timer->clkevt_irq.name		= timer->clockevent_name;
		timer->clkevt_irq.handler	= zevio_timer_interrupt;
		timer->clkevt_irq.dev_id	= timer;
		timer->clkevt_irq.flags		= IRQF_TIMER | IRQF_IRQPOLL;

		setup_irq(irqnr, &timer->clkevt_irq);

		clockevents_config_and_register(&timer->clkevt,
				clk_get_rate(timer->clk), 0x0001, 0xffff);
		pr_info("Added %s as clockevent\n", timer->clockevent_name);
	}

	writel(CNTL_STOP_TIMER, timer->timer2 + IO_CONTROL);
	writel(0, timer->timer2 + IO_CURRENT_VAL);
	writel(0, timer->timer2 + IO_DIVIDER);
	writel(CNTL_RUN_TIMER | CNTL_FOREVER | CNTL_INC,
			timer->timer2 + IO_CONTROL);

	clocksource_mmio_init(timer->timer2 + IO_CURRENT_VAL,
			timer->clocksource_name,
			clk_get_rate(timer->clk),
			200, 16,
			clocksource_mmio_readw_up);

	pr_info("Added %s as clocksource\n", timer->clocksource_name);

	return 0;
error_unmap:
	iounmap(timer->base);
error_free:
	kfree(timer);
	return ret;
}

Contributors
Person Tokens Prop Commits CommitProp
Daniel Tang 530 96.72% 1 50.00%
Viresh Kumar 18 3.28% 1 50.00%
Total 548 100.00% 2 100.00%



static int __init zevio_timer_init(struct device_node *node)
{
	return zevio_timer_add(node);
}

Contributors
Person Tokens Prop Commits CommitProp
Alexander Shiyan 15 83.33% 1 50.00%
Daniel Lezcano 3 16.67% 1 50.00%
Total 18 100.00% 2 100.00%

CLOCKSOURCE_OF_DECLARE(zevio_timer, "lsi,zevio-timer", zevio_timer_init);
Overall Contributors
Person Tokens Prop Commits CommitProp
Daniel Tang 926 91.68% 1 20.00%
Viresh Kumar 64 6.34% 1 20.00%
Alexander Shiyan 16 1.58% 1 20.00%
Daniel Lezcano 4 0.40% 2 40.00%
Total 1010 100.00% 5 100.00%
Directory: drivers/clocksource

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
Daniel Tang	62	100.00%	1	100.00%
Total	62	100.00%	1	100.00%
cregit-Linux how code gets into the kernel

Release 4.12 drivers/clocksource/zevio-timer.c

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Overall Contributors
