;/* ; * FreeRTOS Kernel V10.4.6 ; * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved. ; * ; * SPDX-License-Identifier: MIT ; * ; * Permission is hereby granted, free of charge, to any person obtaining a copy of ; * this software and associated documentation files (the "Software"), to deal in ; * the Software without restriction, including without limitation the rights to ; * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of ; * the Software, and to permit persons to whom the Software is furnished to do so, ; * subject to the following conditions: ; * ; * The above copyright notice and this permission notice shall be included in all ; * copies or substantial portions of the Software. ; * ; * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR ; * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS ; * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR ; * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER ; * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN ; * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ; * ; * https://www.FreeRTOS.org ; * https://github.com/FreeRTOS ; * ; */ RSEG ICODE:CODE CODE32 EXTERN vPortPreemptiveTick EXTERN vTaskSwitchContext PUBLIC vPortYieldProcessor PUBLIC vPortStartFirstTask PUBLIC vPortPreemptiveTickISR #include "ISR_Support.h" ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Starting the first task is just a matter of restoring the context that ; was created by pxPortInitialiseStack(). ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; vPortStartFirstTask: portRESTORE_CONTEXT ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Manual context switch function. This is the SWI hander. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; vPortYieldProcessor: ADD LR, LR, #4 ; Add 4 to the LR to make the LR appear exactly ; as if the context was saved during and IRQ ; handler. portSAVE_CONTEXT ; Save the context of the current task... LDR R0, =vTaskSwitchContext ; before selecting the next task to execute. mov lr, pc BX R0 portRESTORE_CONTEXT ; Restore the context of the selected task. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Preemptive context switch function. This will only ever get used if ; portUSE_PREEMPTION is set to 1 in portmacro.h. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; vPortPreemptiveTickISR: portSAVE_CONTEXT ; Save the context of the current task. LDR R0, =vPortPreemptiveTick ; Increment the tick count - this may wake a task. MOV lr, pc BX R0 portRESTORE_CONTEXT ; Restore the context of the selected task. END