/* MN10300 clockevents
*
* Copyright (C) 2010 Red Hat, Inc. All Rights Reserved.
* Written by Mark Salter (msalter@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/percpu.h>
#include <linux/smp.h>
#include <asm/timex.h>
#include "internal.h"
#ifdef CONFIG_SMP
#if (CONFIG_NR_CPUS > 2) && !defined(CONFIG_GEENERIC_CLOCKEVENTS_BROADCAST)
#error "This doesn't scale well! Need per-core local timers."
#endif
#else /* CONFIG_SMP */
#define stop_jiffies_counter1()
#define reload_jiffies_counter1(x)
#define TMJC1IRQ TMJCIRQ
#endif
static int next_event(unsigned long delta,
struct clock_event_device *evt)
{
unsigned int cpu = smp_processor_id();
if (cpu == 0) {
stop_jiffies_counter();
reload_jiffies_counter(delta - 1);
} else {
stop_jiffies_counter1();
reload_jiffies_counter1(delta - 1);
}
return 0;
}
static void set_clock_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
/* Nothing to do ... */
}
static DEFINE_PER_CPU(struct clock_event_device, mn10300_clockevent_device);
static DEFINE_PER_CPU(struct irqaction, timer_irq);
static irqreturn_t timer_interrupt(int irq, void *dev_id)
{
struct clock_event_device *cd;
unsigned int cpu = smp_processor_id();
if (cpu == 0)
stop_jiffies_counter();
else
stop_jiffies_counter1();
cd = &per_cpu(mn10300_clockevent_device, cpu);
cd->event_handler(cd);
return IRQ_HANDLED;
}
static void event_handler(struct clock_event_device *dev)
{
}
static inline void setup_jiffies_interrupt(int irq,
struct irqaction *action)
{
u16 tmp;
setup_irq(irq, action);
set_intr_level(irq, NUM2GxICR_LEVEL(CONFIG_TIMER_IRQ_LEVEL));
GxICR(irq) |= GxICR_ENABLE | GxICR_DETECT | GxICR_REQUEST;
tmp = GxICR(irq);
}
int __init init_clockevents(void)
{
struct clock_event_device *cd;
struct irqaction *iact;
unsigned int cpu = smp_processor_id();
cd = &per_cpu(mn10300_clockevent_device, cpu);
if (cpu == 0) {
stop_jiffies_counter();
cd->irq = TMJCIRQ;
} else {
stop_jiffies_counter1();
cd->irq = TMJC1IRQ;
}
cd->name = "Timestamp";
cd->features = CLOCK_EVT_FEAT_ONESHOT;
/* Calculate shift/mult. We want to spawn at least 1 second */
clockevents_calc_mult_shift(cd, MN10300_JCCLK, 1);
/* Calculate the min / max delta */
cd->max_delta_ns = clockevent_delta2ns(TMJCBR_MAX, cd);
cd->min_delta_ns = clockevent_delta2ns(100, cd);
cd->rating = 200;
cd->cpumask = cpumask_of(smp_processor_id());
cd->set_mode = set_clock_mode;
cd->event_handler = event_handler;
cd->set_next_event = next_event;
iact = &per_cpu(timer_irq, cpu);
iact->flags = IRQF_DISABLED | IRQF_SHARED | IRQF_TIMER;
iact->handler = timer_interrupt;
clockevents_register_device(cd);
#if defined(CONFIG_SMP) && !defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)
/* setup timer irq affinity so it only runs on this cpu */
{
struct irq_data *data;
data = irq_get_irq_data(cd->irq);
cpumask_copy(data->affinity, cpumask_of(cpu));
iact->flags |= IRQF_NOBALANCING;
}
#endif
if (cpu == 0) {
reload_jiffies_counter(MN10300_JC_PER_HZ - 1);
iact->name = "CPU0 Timer";
} else {
reload_jiffies_counter1(MN10300_JC_PER_HZ - 1);
iact->name = "CPU1 Timer";
}
setup_jiffies_interrupt(cd->irq, iact);
return 0;
}
