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#include <stdint.h>
#include <delay.h>
#include <cpu/x86/msr.h>
#include <cpu/x86/lapic.h>
void init_timer(void)
{
/* Set the apic timer to no interrupts and periodic mode */
lapic_write(LAPIC_LVTT, (1 << 17)|(1<< 16)|(0 << 12)|(0 << 0));
/* Set the divider to 1, no divider */
lapic_write(LAPIC_TDCR, LAPIC_TDR_DIV_1);
/* Set the initial counter to 0xffffffff */
lapic_write(LAPIC_TMICT, 0xffffffff);
}
void udelay(unsigned usecs)
{
uint32_t start, value, ticks;
/* Calculate the number of ticks to run, our FSB runs a 200Mhz */
ticks = usecs * 200;
start = lapic_read(LAPIC_TMCCT);
do {
value = lapic_read(LAPIC_TMCCT);
} while((start - value) < ticks);
}
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