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- #ifndef __ASM_MIPS_DELAY_H
- #define __ASM_MIPS_DELAY_H
-
- extern __inline__ void __delay(int loops)
- {
- __asm__ __volatile__ (
- ".set\tnoreorder\n"
- "1:\tbnez\t%0,1b\n\t"
- "subu\t%0,1\n\t"
- ".set\treorder"
- :"=r" (loops)
- :"0" (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, unsigned long lps)
- {
- usecs *= 0x000010c6; /* 2**32 / 1000000 */
- __asm__("multu\t%0,%1\n\t"
- "mfhi\t%0"
- :"=r" (usecs)
- :"0" (usecs),"r" (lps));
- __delay(usecs);
- }
-
- #ifdef __SMP__
- #define __udelay_val cpu_data[smp_processor_id()].udelay_val
- #else
- #define __udelay_val loops_per_sec
- #endif
-
- #define udelay(usecs) __udelay((usecs),__udelay_val)
-
- /*
- * The different variants for 32/64 bit are pure paranoia. The typical
- * range of numbers that appears for MIPS machines avoids overflows.
- */
- extern __inline__ unsigned long muldiv(unsigned long a, unsigned long b, unsigned long c)
- {
- return (a*b)/c;
- }
-
- #endif /* __ASM_MIPS_DELAY_H */
-