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Russell Kinga09e64f2008-08-05 16:14:15 +01001/*
2 * arch/arm/mach-l7200/include/mach/time.h
3 *
4 * Copyright (C) 2000 Rob Scott (rscott@mtrob.fdns.net)
5 * Steve Hill (sjhill@cotw.com)
6 *
7 * Changelog:
8 * 01-02-2000 RS Created l7200 version, derived from rpc code
9 * 05-03-2000 SJH Complete rewrite
10 */
11#ifndef _ASM_ARCH_TIME_H
12#define _ASM_ARCH_TIME_H
13
14#include <mach/irqs.h>
15
16/*
17 * RTC base register address
18 */
19#define RTC_BASE (IO_BASE_2 + 0x2000)
20
21/*
22 * RTC registers
23 */
24#define RTC_RTCDR (*(volatile unsigned char *) (RTC_BASE + 0x000))
25#define RTC_RTCMR (*(volatile unsigned char *) (RTC_BASE + 0x004))
26#define RTC_RTCS (*(volatile unsigned char *) (RTC_BASE + 0x008))
27#define RTC_RTCC (*(volatile unsigned char *) (RTC_BASE + 0x008))
28#define RTC_RTCDV (*(volatile unsigned char *) (RTC_BASE + 0x00c))
29#define RTC_RTCCR (*(volatile unsigned char *) (RTC_BASE + 0x010))
30
31/*
32 * RTCCR register values
33 */
34#define RTC_RATE_32 0x00 /* 32 Hz tick */
35#define RTC_RATE_64 0x10 /* 64 Hz tick */
36#define RTC_RATE_128 0x20 /* 128 Hz tick */
37#define RTC_RATE_256 0x30 /* 256 Hz tick */
38#define RTC_EN_ALARM 0x01 /* Enable alarm */
39#define RTC_EN_TIC 0x04 /* Enable counter */
40#define RTC_EN_STWDOG 0x08 /* Enable watchdog */
41
42/*
43 * Handler for RTC timer interrupt
44 */
45static irqreturn_t
46timer_interrupt(int irq, void *dev_id)
47{
48 struct pt_regs *regs = get_irq_regs();
49 do_timer(1);
50#ifndef CONFIG_SMP
51 update_process_times(user_mode(regs));
52#endif
53 do_profile(regs);
54 RTC_RTCC = 0; /* Clear interrupt */
55
56 return IRQ_HANDLED;
57}
58
59/*
60 * Set up RTC timer interrupt, and return the current time in seconds.
61 */
62void __init time_init(void)
63{
64 RTC_RTCC = 0; /* Clear interrupt */
65
66 timer_irq.handler = timer_interrupt;
67
68 setup_irq(IRQ_RTC_TICK, &timer_irq);
69
70 RTC_RTCCR = RTC_RATE_128 | RTC_EN_TIC; /* Set rate and enable timer */
71}
72
73#endif