Category

Development Platform
Home > SourceCode/Document > Linux-Unix program > View Code
locks.h
Package: linux-2.4.20.tar.gz　[view]
Upload User: jlfgdled
Upload Date: 2013-04-10
Package Size: 33168k
Code Size: 3k
Category:

Linux-Unix program

Development Platform:

Unix_Linux

locks.h：Code Content
  1. /*
  2.  *  linux/include/asm-arm/proc-armv/locks.h
  3.  *
  4.  *  Copyright (C) 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.  *  Interrupt safe locking assembler. 
  11.  */
  12. #ifndef __ASM_PROC_LOCKS_H
  13. #define __ASM_PROC_LOCKS_H
  15. #define __down_op(ptr,fail)
  16. ({
  17. __asm__ __volatile__(
  18. "@ down_opn"
  19. " mrs ip, cpsrn"
  20. " orr lr, ip, #128n"
  21. " msr cpsr_c, lrn"
  22. " ldr lr, [%0]n"
  23. " subs lr, lr, %1n"
  24. " str lr, [%0]n"
  25. " msr cpsr_c, ipn"
  26. " movmi ip, %0n"
  27. " blmi " SYMBOL_NAME_STR(fail)
  28. :
  29. : "r" (ptr), "I" (1)
  30. : "ip", "lr", "cc");
  31. })
  33. #define __down_op_ret(ptr,fail)
  34. ({
  35. unsigned int ret;
  36. __asm__ __volatile__(
  37. "@ down_op_retn"
  38. " mrs ip, cpsrn"
  39. " orr lr, ip, #128n"
  40. " msr cpsr_c, lrn"
  41. " ldr lr, [%1]n"
  42. " subs lr, lr, %2n"
  43. " str lr, [%1]n"
  44. " msr cpsr_c, ipn"
  45. " movmi ip, %1n"
  46. " movpl ip, #0n"
  47. " blmi " SYMBOL_NAME_STR(fail) "n"
  48. " mov %0, ip"
  49. : "=&r" (ret)
  50. : "r" (ptr), "I" (1)
  51. : "ip", "lr", "cc");
  52. ret;
  53. })
  55. #define __up_op(ptr,wake)
  56. ({
  57. __asm__ __volatile__(
  58. "@ up_opn"
  59. " mrs ip, cpsrn"
  60. " orr lr, ip, #128n"
  61. " msr cpsr_c, lrn"
  62. " ldr lr, [%0]n"
  63. " adds lr, lr, %1n"
  64. " str lr, [%0]n"
  65. " msr cpsr_c, ipn"
  66. " movle ip, %0n"
  67. " blle " SYMBOL_NAME_STR(wake)
  68. :
  69. : "r" (ptr), "I" (1)
  70. : "ip", "lr", "cc");
  71. })
  73. /*
  74.  * The value 0x01000000 supports up to 128 processors and
  75.  * lots of processes.  BIAS must be chosen such that sub'ing
  76.  * BIAS once per CPU will result in the long remaining
  77.  * negative.
  78.  */
  79. #define RW_LOCK_BIAS      0x01000000
  80. #define RW_LOCK_BIAS_STR "0x01000000"
  82. #define __down_op_write(ptr,fail)
  83. ({
  84. __asm__ __volatile__(
  85. "@ down_op_writen"
  86. " mrs ip, cpsrn"
  87. " orr lr, ip, #128n"
  88. " msr cpsr_c, lrn"
  89. " ldr lr, [%0]n"
  90. " subs lr, lr, %1n"
  91. " str lr, [%0]n"
  92. " msr cpsr_c, ipn"
  93. " movne ip, %0n"
  94. " blne " SYMBOL_NAME_STR(fail)
  95. :
  96. : "r" (ptr), "I" (RW_LOCK_BIAS)
  97. : "ip", "lr", "cc");
  98. })
  100. #define __up_op_write(ptr,wake)
  101. ({
  102. __asm__ __volatile__(
  103. "@ up_op_readn"
  104. " mrs ip, cpsrn"
  105. " orr lr, ip, #128n"
  106. " msr cpsr_c, lrn"
  107. " ldr lr, [%0]n"
  108. " adds lr, lr, %1n"
  109. " str lr, [%0]n"
  110. " msr cpsr_c, ipn"
  111. " movcs ip, %0n"
  112. " blcs " SYMBOL_NAME_STR(wake)
  113. :
  114. : "r" (ptr), "I" (RW_LOCK_BIAS)
  115. : "ip", "lr", "cc");
  116. })
  118. #define __down_op_read(ptr,fail)
  119. __down_op(ptr, fail)
  121. #define __up_op_read(ptr,wake)
  122. ({
  123. __asm__ __volatile__(
  124. "@ up_op_readn"
  125. " mrs ip, cpsrn"
  126. " orr lr, ip, #128n"
  127. " msr cpsr_c, lrn"
  128. " ldr lr, [%0]n"
  129. " adds lr, lr, %1n"
  130. " str lr, [%0]n"
  131. " msr cpsr_c, ipn"
  132. " moveq ip, %0n"
  133. " bleq " SYMBOL_NAME_STR(wake)
  134. :
  135. : "r" (ptr), "I" (1)
  136. : "ip", "lr", "cc");
  137. })
  139. #endif