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#ifndef _MIPS_DELAY_H
#define _MIPS_DELAY_H
extern __inline__ void __delay(int loops)
{
__asm__(".align 3\n"
"1:\tbeq\t$0,%0,1b\n\t"
"addiu\t%0,%0,-1\n\t"
:
:"d" (loops));
}
/*
* division by multiplication: you don't have to worry about
* loss of precision.
*
* Use only for very small delays ( < 1 msec). Should probably use a
* lookup table, really, as the multiplications take much too long with
* short delays. This is a "reasonable" implementation, though (and the
* first constant multiplications gets optimized away if the delay is
* a constant)
*/
extern __inline__ void udelay(unsigned long usecs)
{
usecs *= 0x000010c6; /* 2**32 / 1000000 */
__asm__("mul\t%0,%0,%1"
:"=d" (usecs)
:"0" (usecs),"d" (loops_per_sec)
:"ax");
__delay(usecs);
}
#endif /* defined(_MIPS_DELAY_H) */
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