Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
at v2.6.25-rc7 42 lines 721 B view raw
1/* 2 * Precise Delay Loops for SuperH 3 * 4 * Copyright (C) 1999 Niibe Yutaka & Kaz Kojima 5 */ 6 7#include <linux/sched.h> 8#include <linux/delay.h> 9 10void __delay(unsigned long loops) 11{ 12 __asm__ __volatile__( 13 "tst %0, %0\n\t" 14 "1:\t" 15 "bf/s 1b\n\t" 16 " dt %0" 17 : "=r" (loops) 18 : "0" (loops) 19 : "t"); 20} 21 22inline void __const_udelay(unsigned long xloops) 23{ 24 __asm__("dmulu.l %0, %2\n\t" 25 "sts mach, %0" 26 : "=r" (xloops) 27 : "0" (xloops), 28 "r" (HZ * cpu_data[raw_smp_processor_id()].loops_per_jiffy) 29 : "macl", "mach"); 30 __delay(xloops); 31} 32 33void __udelay(unsigned long usecs) 34{ 35 __const_udelay(usecs * 0x000010c6); /* 2**32 / 1000000 */ 36} 37 38void __ndelay(unsigned long nsecs) 39{ 40 __const_udelay(nsecs * 0x00000005); 41} 42