arch/sparc64/lib/delay.c

   1 /* delay.c: Delay loops for sparc64
   2  *
   3  * Copyright (C) 2004, 2006 David S. Miller <davem@davemloft.net>
   4  *
   5  * Based heavily upon x86 variant which is:
   6  *      Copyright (C) 1993 Linus Torvalds
   7  *      Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
   8  */
   9
  10 #include <linux/delay.h>
  11 #include <asm/timer.h>
  12
  13 void __delay(unsigned long loops)
  14 {
  15         unsigned long bclock, now;
  16
  17         bclock = tick_ops->get_tick();
  18         do {
  19                 now = tick_ops->get_tick();
  20         } while ((now-bclock) < loops);
  21 }
  22
  23 /* We used to multiply by HZ after shifting down by 32 bits
  24  * but that runs into problems for higher values of HZ and
  25  * slow cpus.
  26  */
  27 void __const_udelay(unsigned long n)
  28 {
  29         n *= 4;
  30
  31         n *= (cpu_data(raw_smp_processor_id()).udelay_val * (HZ/4));
  32         n >>= 32;
  33
  34         __delay(n + 1);
  35 }
  36
  37 void __udelay(unsigned long n)
  38 {
  39         __const_udelay(n * 0x10c7UL);
  40 }
  41
  42
  43 void __ndelay(unsigned long n)
  44 {
  45         __const_udelay(n * 0x5UL);
  46 }