/*
* arch/score/kernel/time.c
*
* Score Processor version.
*
* Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
* Chen Liqin <liqin.chen@sunplusct.com>
* Lennox Wu <lennox.wu@sunplusct.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <asm/scoreregs.h>
irqreturn_t timer_interrupt(int irq, void *dev_id)
{
struct clock_event_device *evdev = dev_id;
/* clear timer interrupt flag */
outl(1, P_TIMER0_CPP_REG);
evdev->event_handler(evdev);
return IRQ_HANDLED;
}
static struct irqaction timer_irq = {
.handler = timer_interrupt,
.flags = IRQF_DISABLED | IRQF_TIMER,
.name = "timer",
};
static int score_timer_set_next_event(unsigned long delta,
struct clock_event_device *evdev)
{
outl((TMR_M_PERIODIC | TMR_IE_ENABLE), P_TIMER0_CTRL);
outl(delta, P_TIMER0_PRELOAD);
outl(inl(P_TIMER0_CTRL) | TMR_ENABLE, P_TIMER0_CTRL);
return 0;
}
static void score_timer_set_mode(enum clock_event_mode mode,
struct clock_event_device *evdev)
{
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
outl((TMR_M_PERIODIC | TMR_IE_ENABLE), P_TIMER0_CTRL);
outl(SYSTEM_CLOCK/HZ, P_TIMER0_PRELOAD);
outl(inl(P_TIMER0_CTRL) | TMR_ENABLE, P_TIMER0_CTRL);
break;
case CLOCK_EVT_MODE_ONESHOT:
case CLOCK_EVT_MODE_SHUTDOWN:
case CLOCK_EVT_MODE_RESUME:
case CLOCK_EVT_MODE_UNUSED:
break;
default:
BUG();
}
}
static struct clock_event_device score_clockevent = {
.name = "score_clockevent",
.features = CLOCK_EVT_FEAT_PERIODIC,
.shift = 16,
.set_next_event = score_timer_set_next_event,
.set_mode = score_timer_set_mode,
};
void __init time_init(void)
{
timer_irq.dev_id = &score_clockevent;
setup_irq(IRQ_TIMER , &timer_irq);
/* setup COMPARE clockevent */
score_clockevent.mult = div_sc(SYSTEM_CLOCK, NSEC_PER_SEC,
score_clockevent.shift);
score_clockevent.max_delta_ns = clockevent_delta2ns((u32)~0,
&score_clockevent);
score_clockevent.min_delta_ns = clockevent_delta2ns(50,
&score_clockevent) + 1;
score_clockevent.cpumask = cpumask_of(0);
clockevents_register_device(&score_clockevent);
}
