portasm.S 2.5 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. #include "ISR_Support.h"
  30. .global _vPortYield
  31. .global _vPortStartFirstTask
  32. .global _vPortTickISR
  33. .extern _vTaskSwitchContext
  34. .extern _xTaskIncrementTick
  35. .text
  36. .align 2
  37. /* FreeRTOS yield handler. This is installed as the BRK software interrupt
  38. handler. */
  39. _vPortYield:
  40. /* Save the context of the current task. */
  41. portSAVE_CONTEXT
  42. /* Call the scheduler to select the next task. */
  43. call !!_vTaskSwitchContext
  44. /* Restore the context of the next task to run. */
  45. portRESTORE_CONTEXT
  46. retb
  47. /* Starts the scheduler by restoring the context of the task that will execute
  48. first. */
  49. .align 2
  50. _vPortStartFirstTask:
  51. /* Restore the context of whichever task will execute first. */
  52. portRESTORE_CONTEXT
  53. /* An interrupt stack frame is used so the task is started using RETI. */
  54. reti
  55. /* FreeRTOS tick handler. This is installed as the interval timer interrupt
  56. handler. */
  57. .align 2
  58. _vPortTickISR:
  59. /* Save the context of the currently executing task. */
  60. portSAVE_CONTEXT
  61. /* Call the RTOS tick function. */
  62. call !!_xTaskIncrementTick
  63. #if configUSE_PREEMPTION == 1
  64. /* Select the next task to run. */
  65. call !!_vTaskSwitchContext
  66. #endif
  67. /* Retore the context of whichever task will run next. */
  68. portRESTORE_CONTEXT
  69. reti
  70. .end