summaryrefslogtreecommitdiff
path: root/lib_ppc/interrupts.c
blob: 1e540a5c3f79a5dfc3ce327c3991a7c8e7891ac8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
/*
 * (C) Copyright 2000-2002
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * (C) Copyright 2003
 * Gleb Natapov <gnatapov@mrv.com>
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <common.h>
#include <asm/processor.h>
#include <watchdog.h>
#ifdef CONFIG_STATUS_LED
#include <status_led.h>
#endif

#ifdef CONFIG_SHOW_ACTIVITY
	extern void board_show_activity (ulong);
#endif /* CONFIG_SHOW_ACTIVITY */

#ifndef CFG_WATCHDOG_FREQ
#define CFG_WATCHDOG_FREQ (CFG_HZ / 2)
#endif

extern int interrupt_init_cpu (unsigned *);
extern void timer_interrupt_cpu (struct pt_regs *);

static unsigned decrementer_count; /* count value for 1e6/HZ microseconds */

static __inline__ unsigned long get_msr (void)
{
        unsigned long msr;

        asm volatile ("mfmsr %0":"=r" (msr):);

        return msr;
}

static __inline__ void set_msr (unsigned long msr)
{
	asm volatile ("mtmsr %0"::"r" (msr));
}

static __inline__ unsigned long get_dec (void)
{
	unsigned long val;

	asm volatile ("mfdec %0":"=r" (val):);

	return val;
}


static __inline__ void set_dec (unsigned long val)
{
	if (val)
		asm volatile ("mtdec %0"::"r" (val));
}


void enable_interrupts (void)
{
	set_msr (get_msr () | MSR_EE);
}

/* returns flag if MSR_EE was set before */
int disable_interrupts (void)
{
	ulong msr = get_msr ();

	set_msr (msr & ~MSR_EE);
	return ((msr & MSR_EE) != 0);
}

int interrupt_init (void)
{
	int ret;

        /* call cpu specific function from $(CPU)/interrupts.c */
	ret = interrupt_init_cpu (&decrementer_count);

	if (ret)
		return ret;

	set_dec (decrementer_count);

	set_msr (get_msr () | MSR_EE);

	return (0);
}

static volatile ulong timestamp = 0;

void timer_interrupt (struct pt_regs *regs)
{
	/* call cpu specific function from $(CPU)/interrupts.c */
	timer_interrupt_cpu (regs);

	/* Restore Decrementer Count */
	set_dec (decrementer_count);

	timestamp++;

#if defined(CONFIG_WATCHDOG) || defined (CONFIG_HW_WATCHDOG)
	if ((timestamp % (CFG_WATCHDOG_FREQ)) == 0)
		WATCHDOG_RESET ();
#endif    /* CONFIG_WATCHDOG || CONFIG_HW_WATCHDOG */

#ifdef CONFIG_STATUS_LED
        status_led_tick (timestamp);
#endif /* CONFIG_STATUS_LED */

#ifdef CONFIG_SHOW_ACTIVITY
	board_show_activity (timestamp);
#endif /* CONFIG_SHOW_ACTIVITY */
}

void reset_timer (void)
{
	timestamp = 0;
}

ulong get_timer (ulong base)
{
	return (timestamp - base);
}

void set_timer (ulong t)
{
	timestamp = t;
}