ISR_Support.h 3.5 KB

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  1. ;/*
  2. ; * FreeRTOS Kernel V10.4.6
  3. ; * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
  4. ; *
  5. ; * SPDX-License-Identifier: MIT
  6. ; *
  7. ; * Permission is hereby granted, free of charge, to any person obtaining a copy of
  8. ; * this software and associated documentation files (the "Software"), to deal in
  9. ; * the Software without restriction, including without limitation the rights to
  10. ; * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
  11. ; * the Software, and to permit persons to whom the Software is furnished to do so,
  12. ; * subject to the following conditions:
  13. ; *
  14. ; * The above copyright notice and this permission notice shall be included in all
  15. ; * copies or substantial portions of the Software.
  16. ; *
  17. ; * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18. ; * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
  19. ; * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
  20. ; * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
  21. ; * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22. ; * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23. ; *
  24. ; * https://www.FreeRTOS.org
  25. ; * https://github.com/FreeRTOS
  26. ; *
  27. ; */
  28. #include "FreeRTOSConfig.h"
  29. ; Variables used by scheduler
  30. ;------------------------------------------------------------------------------
  31. EXTERN pxCurrentTCB
  32. EXTERN usCriticalNesting
  33. ;------------------------------------------------------------------------------
  34. ; portSAVE_CONTEXT MACRO
  35. ; Saves the context of the general purpose registers, CS and ES (only in far
  36. ; memory mode) registers the usCriticalNesting Value and the Stack Pointer
  37. ; of the active Task onto the task stack
  38. ;------------------------------------------------------------------------------
  39. portSAVE_CONTEXT MACRO
  40. PUSH AX ; Save AX Register to stack.
  41. PUSH HL
  42. MOV A, CS ; Save CS register.
  43. XCH A, X
  44. MOV A, ES ; Save ES register.
  45. PUSH AX
  46. PUSH DE ; Save the remaining general purpose registers.
  47. PUSH BC
  48. MOVW AX, usCriticalNesting ; Save the usCriticalNesting value.
  49. PUSH AX
  50. MOVW AX, pxCurrentTCB ; Save the Stack pointer.
  51. MOVW HL, AX
  52. MOVW AX, SP
  53. MOVW [HL], AX
  54. ENDM
  55. ;------------------------------------------------------------------------------
  56. ;------------------------------------------------------------------------------
  57. ; portRESTORE_CONTEXT MACRO
  58. ; Restores the task Stack Pointer then use this to restore usCriticalNesting,
  59. ; general purpose registers and the CS and ES (only in far memory mode)
  60. ; of the selected task from the task stack
  61. ;------------------------------------------------------------------------------
  62. portRESTORE_CONTEXT MACRO
  63. MOVW AX, pxCurrentTCB ; Restore the Stack pointer.
  64. MOVW HL, AX
  65. MOVW AX, [HL]
  66. MOVW SP, AX
  67. POP AX ; Restore usCriticalNesting value.
  68. MOVW usCriticalNesting, AX
  69. POP BC ; Restore the necessary general purpose registers.
  70. POP DE
  71. POP AX ; Restore the ES register.
  72. MOV ES, A
  73. XCH A, X ; Restore the CS register.
  74. MOV CS, A
  75. POP HL ; Restore general purpose register HL.
  76. POP AX ; Restore AX.
  77. ENDM
  78. ;------------------------------------------------------------------------------