arch/arm/lib/io-writesl.S

   1 /*
   2  *  linux/arch/arm/lib/io-writesl.S
   3  *
   4  *  Copyright (C) 1995-2000 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/linkage.h>
  11 #include <asm/assembler.h>
  12
  13 ENTRY(__raw_writesl)
  14                 teq     r2, #0          @ do we have to check for the zero len?
  15                 moveq   pc, lr
  16                 ands    ip, r1, #3
  17                 bne     3f
  18
  19                 subs    r2, r2, #4
  20                 bmi     2f
  21                 stmfd   sp!, {r4, lr}
  22 1:              ldmia   r1!, {r3, r4, ip, lr}
  23                 subs    r2, r2, #4
  24                 str     r3, [r0, #0]
  25                 str     r4, [r0, #0]
  26                 str     ip, [r0, #0]
  27                 str     lr, [r0, #0]
  28                 bpl     1b
  29                 ldmfd   sp!, {r4, lr}
  30 2:              movs    r2, r2, lsl #31
  31                 ldmcsia r1!, {r3, ip}
  32                 strcs   r3, [r0, #0]
  33                 ldrne   r3, [r1, #0]
  34                 strcs   ip, [r0, #0]
  35                 strne   r3, [r0, #0]
  36                 mov     pc, lr
  37
  38 3:              bic     r1, r1, #3
  39                 ldr     r3, [r1], #4
  40                 cmp     ip, #2
  41                 blt     5f
  42                 bgt     6f
  43
  44 4:              mov     ip, r3, pull #16
  45                 ldr     r3, [r1], #4
  46                 subs    r2, r2, #1
  47                 orr     ip, ip, r3, push #16
  48                 str     ip, [r0]
  49                 bne     4b
  50                 mov     pc, lr
  51
  52 5:              mov     ip, r3, pull #8
  53                 ldr     r3, [r1], #4
  54                 subs    r2, r2, #1
  55                 orr     ip, ip, r3, push #24
  56                 str     ip, [r0]
  57                 bne     5b
  58                 mov     pc, lr
  59
  60 6:              mov     ip, r3, pull #24
  61                 ldr     r3, [r1], #4
  62                 subs    r2, r2, #1
  63                 orr     ip, ip, r3, push #8
  64                 str     ip, [r0]
  65                 bne     6b
  66                 mov     pc, lr
  67 ENDPROC(__raw_writesl)