; /* | |
* ; * FreeRTOS Kernel V10.3.1 | |
* ; * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. | |
* ; * | |
* ; * 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. | |
* ; * | |
* ; * http://www.FreeRTOS.org | |
* ; * http://aws.amazon.com/freertos | |
* ; * | |
* ; * 1 tab == 4 spaces! | |
* ; */ | |
#include "FreeRTOSConfig.h" | |
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Variables used by scheduler | |
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------------------------------------------------------------------------------ | |
EXTERN pxCurrentTCB | |
EXTERN usCriticalNesting | |
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------------------------------------------------------------------------------ | |
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portSAVE_CONTEXT MACRO | |
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Saves the context of the general purpose registers, CS and ES( only in far | |
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memory mode ) registers the usCriticalNesting Value and the Stack Pointer | |
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of the active Task onto the task stack | |
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------------------------------------------------------------------------------ | |
portSAVE_CONTEXT MACRO | |
PUSH AX; | |
Save AX Register to stack. | |
PUSH HL | |
MOV A, CS; | |
Save CS register. | |
XCH A, X | |
MOV A, ES; | |
Save ES register. | |
PUSH AX | |
PUSH DE; | |
Save the remaining general purpose registers. | |
PUSH BC | |
MOVW AX, usCriticalNesting; | |
Save the usCriticalNesting value. | |
PUSH AX | |
MOVW AX, pxCurrentTCB; | |
Save the Stack pointer. | |
MOVW HL, AX | |
MOVW AX, SP | |
MOVW[ HL ], AX | |
ENDM | |
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------------------------------------------------------------------------------ | |
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------------------------------------------------------------------------------ | |
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portRESTORE_CONTEXT MACRO | |
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Restores the task Stack Pointer then use this to restore usCriticalNesting, | |
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general purpose registers and the CS and ES( only in far memory mode ) | |
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of the selected task from the task stack | |
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------------------------------------------------------------------------------ | |
portRESTORE_CONTEXT MACRO | |
MOVW AX, pxCurrentTCB; | |
Restore the Stack pointer. | |
MOVW HL, AX | |
MOVW AX, [ HL ] | |
MOVW SP, AX | |
POP AX; | |
Restore usCriticalNesting value. | |
MOVW usCriticalNesting, AX | |
POP BC; | |
Restore the necessary general purpose registers. | |
POP DE | |
POP AX; | |
Restore the ES register. | |
MOV ES, A | |
XCH A, X; | |
Restore the CS register. | |
MOV CS, A | |
POP HL; | |
Restore general purpose register HL. | |
POP AX; | |
Restore AX. | |
ENDM | |
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------------------------------------------------------------------------------ |