2 * FreeRTOS Kernel V10.4.4
3 * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
5 * SPDX-License-Identifier: MIT
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:
14 * The above copyright notice and this permission notice shall be included in all
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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
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24 * https://www.FreeRTOS.org
25 * https://github.com/FreeRTOS
29 #include "FreeRTOSConfig.h"
38 * If the cooperative scheduler is in use this simply increments the tick
41 * If the preemptive scheduler is in use a context switch can also occur.
46 call #_xTaskIncrementTick
48 jeq _SkipContextSwitch
49 call #_vTaskSwitchContext
52 /*-----------------------------------------------------------*/
56 * Manual context switch called by the portYIELD() macro.
60 /* Mimic an interrupt by pushing the SR. */
63 /* Now the SR is stacked we can disable interrupts. */
66 /* Save the context of the current task. */
69 /* Switch to the highest priority task that is ready to run. */
70 call #_vTaskSwitchContext
72 /* Restore the context of the new task. */
74 /*-----------------------------------------------------------*/
78 * Start off the scheduler by initialising the RTOS tick timer, then restoring
79 * the context of the first task.
81 _xPortStartScheduler::
83 /* Setup the hardware to generate the tick. Interrupts are disabled
84 when this function is called. */
85 call #_prvSetupTimerInterrupt
87 /* Restore the context of the first task that is going to run. */
89 /*-----------------------------------------------------------*/
92 /* Place the tick ISR in the correct vector. */