i386/linux/linux-2.3.21/arch/arm/lib/delay.S

   1 /*
   2  * linux/arch/arm/lib/delay.S
   3  *
   4  * Copyright (C) 1995, 1996 Russell King
   5  */
   6 #include <linux/linkage.h>
   7 #include <asm/assembler.h>
   8                 .text
   9
  10 LC0:            .word   SYMBOL_NAME(loops_per_sec)
  11
  12 ENTRY(udelay)
  13                 mov     r2, #0x1000
  14                 orr     r2, r2, #0x00c6
  15                 mul     r1, r0, r2
  16                 ldr     r2, LC0
  17                 ldr     r2, [r2]
  18                 mov     r1, r1, lsr #11
  19                 mov     r2, r2, lsr #11
  20                 mul     r0, r1, r2
  21                 movs    r0, r0, lsr #10
  22                 RETINSTR(moveq,pc,lr)
  23
  24 @ Delay routine
  25 ENTRY(__delay)
  26                 subs    r0, r0, #1
  27                 RETINSTR(movcc,pc,lr)
  28                 subs    r0, r0, #1
  29                 RETINSTR(movcc,pc,lr)
  30                 subs    r0, r0, #1
  31                 RETINSTR(movcc,pc,lr)
  32                 subs    r0, r0, #1
  33                 RETINSTR(movcc,pc,lr)
  34                 subs    r0, r0, #1
  35                 RETINSTR(movcc,pc,lr)
  36                 subs    r0, r0, #1
  37                 RETINSTR(movcc,pc,lr)
  38                 subs    r0, r0, #1
  39                 RETINSTR(movcc,pc,lr)
  40                 subs    r0, r0, #1
  41                 bcs     SYMBOL_NAME(__delay)
  42                 RETINSTR(mov,pc,lr)
  43