| ;/*
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| ; * FreeRTOS Kernel <DEVELOPMENT BRANCH>
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| ; * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
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| ; *
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| ; * SPDX-License-Identifier: MIT |
| ; * |
| ; * Permission is hereby granted, free of charge, to any person obtaining a copy of
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| ; * this software and associated documentation files (the "Software"), to deal in
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| ; * the Software without restriction, including without limitation the rights to
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| ; * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
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| ; * the Software, and to permit persons to whom the Software is furnished to do so,
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| ; * subject to the following conditions:
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| ; *
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| ; * The above copyright notice and this permission notice shall be included in all
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| ; * copies or substantial portions of the Software.
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| ; *
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| ; * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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| ; * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
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| ; * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
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| ; * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
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| ; * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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| ; * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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| ; *
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| ; * https://www.FreeRTOS.org
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| ; * https://github.com/FreeRTOS
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| ; *
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| ; */
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|
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| ; * The definition of the "register test" tasks, as described at the top of
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| ; * main.c
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| .include data_model.h
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| .global xTaskIncrementTick
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| .global vTaskSwitchContext
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| .global vPortSetupTimerInterrupt
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| .global pxCurrentTCB
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| .global usCriticalNesting
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| .def vPortPreemptiveTickISR
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| .def vPortCooperativeTickISR
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| .def vPortYield
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| .def xPortStartScheduler
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| ;-----------------------------------------------------------
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| portSAVE_CONTEXT .macro
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| ;Save the remaining registers.
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| pushm_x #12, r15
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| mov.w &usCriticalNesting, r14
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| push_x r14
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| mov_x &pxCurrentTCB, r12
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| mov_x sp, 0( r12 )
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| .endm
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| ;-----------------------------------------------------------
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|
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| portRESTORE_CONTEXT .macro
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| mov_x &pxCurrentTCB, r12
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| mov_x @r12, sp
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| pop_x r15
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| mov.w r15, &usCriticalNesting
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| popm_x #12, r15
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| nop
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| pop.w sr
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| nop
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| ret_x
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| .endm
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| ;-----------------------------------------------------------
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|
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| ;*
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| ;* The RTOS tick ISR.
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| ;*
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| ;* If the cooperative scheduler is in use this simply increments the tick
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| ;* count.
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| ;*
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| ;* If the preemptive scheduler is in use a context switch can also occur.
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| ;*/
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|
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| .text
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| .align 2
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|
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| vPortPreemptiveTickISR: .asmfunc
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|
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| ; The sr is not saved in portSAVE_CONTEXT() because vPortYield() needs
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| ;to save it manually before it gets modified (interrupts get disabled).
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| push.w sr
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| portSAVE_CONTEXT
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|
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| call_x #xTaskIncrementTick
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| call_x #vTaskSwitchContext
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|
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| portRESTORE_CONTEXT
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| .endasmfunc
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| ;-----------------------------------------------------------
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|
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| .align 2
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| vPortCooperativeTickISR: .asmfunc
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|
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| ; The sr is not saved in portSAVE_CONTEXT() because vPortYield() needs
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| ;to save it manually before it gets modified (interrupts get disabled).
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| push.w sr
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| portSAVE_CONTEXT
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| call_x #xTaskIncrementTick
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|
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| portRESTORE_CONTEXT
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| .endasmfunc
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| ;-----------------------------------------------------------
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|
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| ;
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| ; Manual context switch called by the portYIELD() macro.
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| ;
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| .align 2
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| vPortYield: .asmfunc
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|
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| ; The sr needs saving before it is modified.
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| push.w sr
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|
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| ; Now the SR is stacked we can disable interrupts.
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| dint
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| nop
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|
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| ; Save the context of the current task.
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| portSAVE_CONTEXT
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|
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| ; Select the next task to run.
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| call_x #vTaskSwitchContext
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| ; Restore the context of the new task.
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| portRESTORE_CONTEXT
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| .endasmfunc
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| ;-----------------------------------------------------------
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|
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| ;
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| ; Start off the scheduler by initialising the RTOS tick timer, then restoring
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| ; the context of the first task.
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| ;
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|
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| .align 2
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|
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| xPortStartScheduler: .asmfunc
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|
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| ; Setup the hardware to generate the tick. Interrupts are disabled
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| ; when this function is called.
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| call_x #vPortSetupTimerInterrupt
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| ; Restore the context of the first task that is going to run.
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| portRESTORE_CONTEXT
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| .endasmfunc
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| ;-----------------------------------------------------------
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|
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| .end
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|