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

https://bitbucket.org/evzijst/gittest · Assembly · 130 lines · 96 code · 25 blank · 9 comment · 0 complexity · e9f5e117edc9311225f324849704a3c2 MD5 · raw file 

    

  1. /*
    2. 

  2.  *  linux/arch/arm/lib/io-readsw-armv4.S
    3. 

  3.  *
    4. 

  4.  *  Copyright (C) 1995-2000 Russell King
    5. 

  5.  *
    6. 

  6.  * This program is free software; you can redistribute it and/or modify
    7. 

  7.  * it under the terms of the GNU General Public License version 2 as
    8. 

  8.  * published by the Free Software Foundation.
    9. 

  9.  */
    10. 

  10. #include <linux/linkage.h>
    11. 

  11. #include <asm/assembler.h>
    12. 

  12. 

  13. 		.macro	pack, rd, hw1, hw2
    14. 

  14. #ifndef __ARMEB__
    15. 

  15. 		orr	\rd, \hw1, \hw2, lsl #16
    16. 

  16. #else
    17. 

  17. 		orr	\rd, \hw2, \hw1, lsl #16
    18. 

  18. #endif
    19. 

  19. 		.endm
    20. 

  20. 

  21. .insw_align:	movs	ip, r1, lsl #31
    22. 

  22. 		bne	.insw_noalign
    23. 

  23. 		ldrh	ip, [r0]
    24. 

  24. 		sub	r2, r2, #1
    25. 

  25. 		strh	ip, [r1], #2
    26. 

  26. 

  27. ENTRY(__raw_readsw)
    28. 

  28. 		teq	r2, #0
    29. 

  29. 		moveq	pc, lr
    30. 

  30. 		tst	r1, #3
    31. 

  31. 		bne	.insw_align
    32. 

  32. 

  33. 		stmfd	sp!, {r4, r5, lr}
    34. 

  34. 

  35. 		subs	r2, r2, #8
    36. 

  36. 		bmi	.no_insw_8
    37. 

  37. 

  38. .insw_8_lp:	ldrh	r3, [r0]
    39. 

  39. 		ldrh	r4, [r0]
    40. 

  40. 		pack	r3, r3, r4
    41. 

  41. 

  42. 		ldrh	r4, [r0]
    43. 

  43. 		ldrh	r5, [r0]
    44. 

  44. 		pack	r4, r4, r5
    45. 

  45. 

  46. 		ldrh	r5, [r0]
    47. 

  47. 		ldrh	ip, [r0]
    48. 

  48. 		pack	r5, r5, ip
    49. 

  49. 

  50. 		ldrh	ip, [r0]
    51. 

  51. 		ldrh	lr, [r0]
    52. 

  52. 		pack	ip, ip, lr
    53. 

  53. 

  54. 		subs	r2, r2, #8
    55. 

  55. 		stmia	r1!, {r3 - r5, ip}
    56. 

  56. 		bpl	.insw_8_lp
    57. 

  57. 

  58. .no_insw_8:	tst	r2, #4
    59. 

  59. 		beq	.no_insw_4
    60. 

  60. 

  61. 		ldrh	r3, [r0]
    62. 

  62. 		ldrh	r4, [r0]
    63. 

  63. 		pack	r3, r3, r4
    64. 

  64. 

  65. 		ldrh	r4, [r0]
    66. 

  66. 		ldrh	ip, [r0]
    67. 

  67. 		pack	r4, r4, ip
    68. 

  68. 

  69. 		stmia	r1!, {r3, r4}
    70. 

  70. 

  71. .no_insw_4:	movs	r2, r2, lsl #31
    72. 

  72. 		bcc	.no_insw_2
    73. 

  73. 

  74. 		ldrh	r3, [r0]
    75. 

  75. 		ldrh	ip, [r0]
    76. 

  76. 		pack	r3, r3, ip
    77. 

  77. 		str	r3, [r1], #4
    78. 

  78. 

  79. .no_insw_2:	ldrneh	r3, [r0]
    80. 

  80. 		strneh	r3, [r1]
    81. 

  81. 

  82. 		ldmfd	sp!, {r4, r5, pc}
    83. 

  83. 

  84. #ifdef __ARMEB__
    85. 

  85. #define _BE_ONLY_(code...)	code
    86. 

  86. #define _LE_ONLY_(code...)
    87. 

  87. #define push_hbyte0		lsr #8
    88. 

  88. #define pull_hbyte1		lsl #24
    89. 

  89. #else
    90. 

  90. #define _BE_ONLY_(code...)
    91. 

  91. #define _LE_ONLY_(code...) code
    92. 

  92. #define push_hbyte0		lsl #24
    93. 

  93. #define pull_hbyte1		lsr #8
    94. 

  94. #endif
    95. 

  95. 

  96. .insw_noalign:	stmfd	sp!, {r4, lr}
    97. 

  97. 		ldrccb	ip, [r1, #-1]!
    98. 

  98. 		bcc	1f
    99. 

  99. 

  100. 		ldrh	ip, [r0]
    101. 

  101. 		sub	r2, r2, #1
    102. 

  102.    _BE_ONLY_(	mov	ip, ip, ror #8		)
    103. 

  103. 		strb	ip, [r1], #1
    104. 

  104.    _LE_ONLY_(	mov	ip, ip, lsr #8		)
    105. 

  105.    _BE_ONLY_(	mov	ip, ip, lsr #24		)
    106. 

  106. 

  107. 1:		subs	r2, r2, #2
    108. 

  108. 		bmi	3f
    109. 

  109.    _BE_ONLY_(	mov	ip, ip, lsl #24		)
    110. 

  110. 

  111. 2:		ldrh	r3, [r0]
    112. 

  112. 		ldrh	r4, [r0]
    113. 

  113. 		subs	r2, r2, #2
    114. 

  114. 		orr	ip, ip, r3, lsl #8
    115. 

  115. 		orr	ip, ip, r4, push_hbyte0
    116. 

  116. 		str	ip, [r1], #4
    117. 

  117. 		mov	ip, r4, pull_hbyte1
    118. 

  118. 		bpl	2b
    119. 

  119. 

  120.    _BE_ONLY_(	mov	ip, ip, lsr #24		)
    121. 

  121. 

  122. 3:		tst	r2, #1
    123. 

  123. 		strb	ip, [r1], #1
    124. 

  124. 		ldrneh	ip, [r0]
    125. 

  125.    _BE_ONLY_(	movne	ip, ip, ror #8		)
    126. 

  126. 		strneb	ip, [r1], #1
    127. 

  127.    _LE_ONLY_(	movne	ip, ip, lsr #8		)
    128. 

  128.    _BE_ONLY_(	movne	ip, ip, lsr #24		)
    129. 

  129. 		strneb	ip, [r1]
    130. 

  130. 		ldmfd	sp!, {r4, pc}
    131.