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