interrupts.c 3.19 KB
Newer Older
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153
/*
 * (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
void board_show_activity (ulong) __attribute__((weak, alias("__board_show_activity")));

void __board_show_activity (ulong dummy)
{
	return;
}
#endif /* CONFIG_SHOW_ACTIVITY */

#ifndef CONFIG_SYS_WATCHDOG_FREQ
#define CONFIG_SYS_WATCHDOG_FREQ (CONFIG_SYS_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 % (CONFIG_SYS_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;
}