arch/arm/lib/io-writesw-armv4.S

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  *  linux/arch/arm/lib/io-writesw-armv4.S
   4  *
   5  *  Copyright (C) 1995-2000 Russell King
   6  */
   7 #include <linux/linkage.h>
   8 #include <asm/assembler.h>
   9
  10                 .macro  outword, rd
  11 #ifndef __ARMEB__
  12                 strh    \rd, [r0]
  13                 mov     \rd, \rd, lsr #16
  14                 strh    \rd, [r0]
  15 #else
  16                 mov     lr, \rd, lsr #16
  17                 strh    lr, [r0]
  18                 strh    \rd, [r0]
  19 #endif
  20                 .endm
  21
  22 .Loutsw_align:  movs    ip, r1, lsl #31
  23                 bne     .Loutsw_noalign
  24
  25                 ldrh    r3, [r1], #2
  26                 sub     r2, r2, #1
  27                 strh    r3, [r0]
  28
  29 ENTRY(__raw_writesw)
  30                 teq     r2, #0
  31                 reteq   lr
  32                 ands    r3, r1, #3
  33                 bne     .Loutsw_align
  34
  35                 stmfd   sp!, {r4, r5, lr}
  36
  37                 subs    r2, r2, #8
  38                 bmi     .Lno_outsw_8
  39
  40 .Loutsw_8_lp:   ldmia   r1!, {r3, r4, r5, ip}
  41                 subs    r2, r2, #8
  42                 outword r3
  43                 outword r4
  44                 outword r5
  45                 outword ip
  46                 bpl     .Loutsw_8_lp
  47
  48 .Lno_outsw_8:   tst     r2, #4
  49                 beq     .Lno_outsw_4
  50
  51                 ldmia   r1!, {r3, ip}
  52                 outword r3
  53                 outword ip
  54
  55 .Lno_outsw_4:   movs    r2, r2, lsl #31
  56                 bcc     .Lno_outsw_2
  57
  58                 ldr     r3, [r1], #4
  59                 outword r3
  60
  61 .Lno_outsw_2:   ldrhne  r3, [r1]
  62                 strhne  r3, [r0]
  63
  64                 ldmfd   sp!, {r4, r5, pc}
  65
  66 #ifdef __ARMEB__
  67 #define pull_hbyte0     lsl #8
  68 #define push_hbyte1     lsr #24
  69 #else
  70 #define pull_hbyte0     lsr #24
  71 #define push_hbyte1     lsl #8
  72 #endif
  73
  74 .Loutsw_noalign:
  75  ARM(           ldr     r3, [r1, -r3]!  )
  76  THUMB(         rsb     r3, r3, #0      )
  77  THUMB(         ldr     r3, [r1, r3]    )
  78  THUMB(         sub     r1, r3          )
  79                 subcs   r2, r2, #1
  80                 bcs     2f
  81                 subs    r2, r2, #2
  82                 bmi     3f
  83
  84 1:              mov     ip, r3, lsr #8
  85                 strh    ip, [r0]
  86 2:              mov     ip, r3, pull_hbyte0
  87                 ldr     r3, [r1, #4]!
  88                 subs    r2, r2, #2
  89                 orr     ip, ip, r3, push_hbyte1
  90                 strh    ip, [r0]
  91                 bpl     1b
  92
  93                 tst     r2, #1
  94 3:              movne   ip, r3, lsr #8
  95                 strhne  ip, [r0]
  96                 ret     lr
  97 ENDPROC(__raw_writesw)