2 * arch/score/kernel/time.c
4 * Score Processor version.
6 * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
7 * Chen Liqin <liqin.chen@sunplusct.com>
8 * Lennox Wu <lennox.wu@sunplusct.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, see the file COPYING, or write
22 * to the Free Software Foundation, Inc.,
23 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
26 #include <linux/clockchips.h>
27 #include <linux/interrupt.h>
29 #include <asm/scoreregs.h>
31 static irqreturn_t
timer_interrupt(int irq
, void *dev_id
)
33 struct clock_event_device
*evdev
= dev_id
;
35 /* clear timer interrupt flag */
36 outl(1, P_TIMER0_CPP_REG
);
37 evdev
->event_handler(evdev
);
42 static struct irqaction timer_irq
= {
43 .handler
= timer_interrupt
,
48 static int score_timer_set_next_event(unsigned long delta
,
49 struct clock_event_device
*evdev
)
51 outl((TMR_M_PERIODIC
| TMR_IE_ENABLE
), P_TIMER0_CTRL
);
52 outl(delta
, P_TIMER0_PRELOAD
);
53 outl(inl(P_TIMER0_CTRL
) | TMR_ENABLE
, P_TIMER0_CTRL
);
58 static int score_timer_set_periodic(struct clock_event_device
*evt
)
60 outl((TMR_M_PERIODIC
| TMR_IE_ENABLE
), P_TIMER0_CTRL
);
61 outl(SYSTEM_CLOCK
/ HZ
, P_TIMER0_PRELOAD
);
62 outl(inl(P_TIMER0_CTRL
) | TMR_ENABLE
, P_TIMER0_CTRL
);
66 static struct clock_event_device score_clockevent
= {
67 .name
= "score_clockevent",
68 .features
= CLOCK_EVT_FEAT_PERIODIC
,
70 .set_next_event
= score_timer_set_next_event
,
71 .set_state_periodic
= score_timer_set_periodic
,
74 void __init
time_init(void)
76 timer_irq
.dev_id
= &score_clockevent
;
77 setup_irq(IRQ_TIMER
, &timer_irq
);
79 /* setup COMPARE clockevent */
80 score_clockevent
.mult
= div_sc(SYSTEM_CLOCK
, NSEC_PER_SEC
,
81 score_clockevent
.shift
);
82 score_clockevent
.max_delta_ns
= clockevent_delta2ns((u32
)~0,
84 score_clockevent
.min_delta_ns
= clockevent_delta2ns(50,
85 &score_clockevent
) + 1;
86 score_clockevent
.cpumask
= cpumask_of(0);
87 clockevents_register_device(&score_clockevent
);