2
* linux/arch/arm/mach-clps711x/time.c
4
* Copyright (C) 2001 Deep Blue Solutions Ltd.
6
* This program is free software; you can redistribute it and/or modify
7
* it under the terms of the GNU General Public License version 2 as
8
* published by the Free Software Foundation.
10
* This program is distributed in the hope that it will be useful,
11
* but WITHOUT ANY WARRANTY; without even the implied warranty of
12
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13
* GNU General Public License for more details.
15
* You should have received a copy of the GNU General Public License
16
* along with this program; if not, write to the Free Software
17
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19
#include <linux/timex.h>
20
#include <linux/init.h>
21
#include <linux/interrupt.h>
22
#include <linux/irq.h>
23
#include <linux/sched.h>
26
#include <mach/hardware.h>
29
#include <asm/hardware/clps7111.h>
31
#include <asm/mach/time.h>
35
* gettimeoffset() returns time since last timer tick, in usecs.
37
* 'LATCH' is hwclock ticks (see CLOCK_TICK_RATE in timex.h) per jiffy.
38
* 'tick' is usecs per jiffy.
40
static unsigned long clps711x_gettimeoffset(void)
42
unsigned long hwticks;
43
hwticks = LATCH - (clps_readl(TC2D) & 0xffff); /* since last underflow */
44
return (hwticks * (tick_nsec / 1000)) / LATCH;
48
* IRQ handler for the timer
51
p720t_timer_interrupt(int irq, void *dev_id)
57
static struct irqaction clps711x_timer_irq = {
58
.name = "CLPS711x Timer Tick",
59
.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
60
.handler = p720t_timer_interrupt,
63
static void __init clps711x_timer_init(void)
68
syscon = clps_readl(SYSCON1);
69
syscon |= SYSCON1_TC2S | SYSCON1_TC2M;
70
clps_writel(syscon, SYSCON1);
72
clps_writel(LATCH-1, TC2D); /* 512kHz / 100Hz - 1 */
74
setup_irq(IRQ_TC2OI, &clps711x_timer_irq);
77
tv.tv_sec = clps_readl(RTCDR);
81
struct sys_timer clps711x_timer = {
82
.init = clps711x_timer_init,
83
.offset = clps711x_gettimeoffset,