linux/arch/arm/mach-footbridge/dc21285-timer.c

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/*
* linux/arch/arm/mach-footbridge/dc21285-timer.c
*
* Copyright (C) 1998 Russell King.
* Copyright (C) 1998 Phil Blundell
*/
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <asm/irq.h>
#include <asm/hardware/dec21285.h>
#include <asm/mach/time.h>
#include "common.h"
static cycle_t cksrc_dc21285_read(struct clocksource *cs)
{
return cs->mask - *CSR_TIMER2_VALUE;
}
static int cksrc_dc21285_enable(struct clocksource *cs)
{
*CSR_TIMER2_LOAD = cs->mask;
*CSR_TIMER2_CLR = 0;
*CSR_TIMER2_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_DIV16;
return 0;
}
static void cksrc_dc21285_disable(struct clocksource *cs)
{
*CSR_TIMER2_CNTL = 0;
}
static struct clocksource cksrc_dc21285 = {
.name = "dc21285_timer2",
.rating = 200,
.read = cksrc_dc21285_read,
.enable = cksrc_dc21285_enable,
.disable = cksrc_dc21285_disable,
.mask = CLOCKSOURCE_MASK(24),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
static void ckevt_dc21285_set_mode(enum clock_event_mode mode,
struct clock_event_device *c)
{
switch (mode) {
case CLOCK_EVT_MODE_RESUME:
case CLOCK_EVT_MODE_PERIODIC:
*CSR_TIMER1_CLR = 0;
*CSR_TIMER1_LOAD = (mem_fclk_21285 + 8 * HZ) / (16 * HZ);
*CSR_TIMER1_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD |
TIMER_CNTL_DIV16;
break;
default:
*CSR_TIMER1_CNTL = 0;
break;
}
}
static struct clock_event_device ckevt_dc21285 = {
.name = "dc21285_timer1",
.features = CLOCK_EVT_FEAT_PERIODIC,
.rating = 200,
.irq = IRQ_TIMER1,
.set_mode = ckevt_dc21285_set_mode,
};
static irqreturn_t timer1_interrupt(int irq, void *dev_id)
{
struct clock_event_device *ce = dev_id;
*CSR_TIMER1_CLR = 0;
ce->event_handler(ce);
return IRQ_HANDLED;
}
static struct irqaction footbridge_timer_irq = {
.name = "dc21285_timer1",
.handler = timer1_interrupt,
.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
.dev_id = &ckevt_dc21285,
};
/*
* Set up timer interrupt.
*/
static void __init footbridge_timer_init(void)
{
struct clock_event_device *ce = &ckevt_dc21285;
clocksource_register_hz(&cksrc_dc21285, (mem_fclk_21285 + 8) / 16);
setup_irq(ce->irq, &footbridge_timer_irq);
clockevents_calc_mult_shift(ce, mem_fclk_21285, 5);
ce->max_delta_ns = clockevent_delta2ns(0xffffff, ce);
ce->min_delta_ns = clockevent_delta2ns(0x000004, ce);
clockevents_register_device(ce);
}
struct sys_timer footbridge_timer = {
.init = footbridge_timer_init,
};