original_kernel/arch/i386/kernel/i8253.c

33 lines
649 B
C

/*
* i8253.c 8253/PIT functions
*
*/
#include <linux/spinlock.h>
#include <linux/jiffies.h>
#include <linux/sysdev.h>
#include <linux/module.h>
#include <linux/init.h>
#include <asm/smp.h>
#include <asm/delay.h>
#include <asm/i8253.h>
#include <asm/io.h>
#include "io_ports.h"
DEFINE_SPINLOCK(i8253_lock);
EXPORT_SYMBOL(i8253_lock);
void setup_pit_timer(void)
{
unsigned long flags;
spin_lock_irqsave(&i8253_lock, flags);
outb_p(0x34,PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
udelay(10);
outb_p(LATCH & 0xff , PIT_CH0); /* LSB */
udelay(10);
outb(LATCH >> 8 , PIT_CH0); /* MSB */
spin_unlock_irqrestore(&i8253_lock, flags);
}