Linux-2.6.12-rc2
[linux-2.6.git] / arch / arm / mach-epxa10db / time.c
1 /*
2  *  linux/arch/arm/mach-epxa10db/time.c
3  *
4  *  Copyright (C) 2000 Deep Blue Solutions
5  *  Copyright (C) 2001 Altera Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/sched.h>
15
16 #include <asm/hardware.h>
17 #include <asm/system.h>
18 #include <asm/leds.h>
19
20 #include <asm/mach/time.h>
21
22 #define TIMER00_TYPE (volatile unsigned int*)
23 #include <asm/arch/timer00.h>
24
25 static int epxa10db_set_rtc(void)
26 {
27         return 1;
28 }
29
30 static int epxa10db_rtc_init(void)
31 {
32         set_rtc = epxa10db_set_rtc;
33
34         return 0;
35 }
36
37 __initcall(epxa10db_rtc_init);
38
39
40 /*
41  * IRQ handler for the timer
42  */
43 static irqreturn_t
44 epxa10db_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
45 {
46         write_seqlock(&xtime_lock);
47
48         // ...clear the interrupt
49         *TIMER0_CR(IO_ADDRESS(EXC_TIMER00_BASE))|=TIMER0_CR_CI_MSK;
50
51         timer_tick(regs);
52         write_sequnlock(&xtime_lock);
53
54         return IRQ_HANDLED;
55 }
56
57 static struct irqaction epxa10db_timer_irq = {
58         .name           = "Excalibur Timer Tick",
59         .flags          = SA_INTERRUPT,
60         .handler        = epxa10db_timer_interrupt
61 };
62
63 /*
64  * Set up timer interrupt, and return the current time in seconds.
65  */
66 static void __init epxa10db_timer_init(void)
67 {
68         /* Start the timer */
69         *TIMER0_LIMIT(IO_ADDRESS(EXC_TIMER00_BASE))=(unsigned int)(EXC_AHB2_CLK_FREQUENCY/200);
70         *TIMER0_PRESCALE(IO_ADDRESS(EXC_TIMER00_BASE))=1;
71         *TIMER0_CR(IO_ADDRESS(EXC_TIMER00_BASE))=TIMER0_CR_IE_MSK | TIMER0_CR_S_MSK;
72
73         setup_irq(IRQ_TIMER0, &epxa10db_timer_irq);
74 }
75
76 struct sys_timer epxa10db_timer = {
77         .init           = epxa10db_timer_init,
78 };