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/*
* Precise Delay Loops for i386
*
* Copyright (C) 1993 Linus Torvalds
* Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
*
* The __delay function must _NOT_ be inlined as its execution time
* depends wildly on alignment on many x86 processors.
*/
#include <linux/sched.h>
#include <linux/delay.h>
#ifdef __SMP__
#include <asm/smp.h>
#endif
#ifdef __SMP__
#define __udelay_val cpu_data[smp_processor_id()].udelay_val
#else
#define __udelay_val loops_per_sec
#endif
void __delay(unsigned long loops)
{
__asm__ __volatile__(
"1:\tdecl %0\n\tjns 1b"
:/* no outputs */
:"a" (loops)
:"ax");
}
inline void __const_udelay(unsigned long xloops)
{
__asm__("mull %0"
:"=d" (xloops)
:"a" (xloops),"0" (__udelay_val)
:"ax");
__delay(xloops);
}
void __udelay(unsigned long usecs)
{
__const_udelay(usecs * 0x000010c6); /* 2**32 / 1000000 */
}
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