| ;/*
|
| ; * FreeRTOS Kernel <DEVELOPMENT BRANCH>
|
| ; * 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
|
| ; *
|
| ; */
|
|
|
| #include "FreeRTOSConfig.h"
|
|
|
| ; Variables used by scheduler
|
| ;------------------------------------------------------------------------------
|
| EXTERN pxCurrentTCB
|
| EXTERN usCriticalNesting
|
|
|
| ;------------------------------------------------------------------------------
|
| ; portSAVE_CONTEXT MACRO
|
| ; Saves the context of the general purpose registers, CS and ES (only in far
|
| ; memory mode) registers the usCriticalNesting Value and the Stack Pointer
|
| ; of the active Task onto the task stack
|
| ;------------------------------------------------------------------------------
|
| 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
|
| ;------------------------------------------------------------------------------
|
|
|
| ;------------------------------------------------------------------------------
|
| ; portRESTORE_CONTEXT MACRO
|
| ; Restores the task Stack Pointer then use this to restore usCriticalNesting,
|
| ; general purpose registers and the CS and ES (only in far memory mode)
|
| ; of the selected task from the task stack
|
| ;------------------------------------------------------------------------------
|
| 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
|
| ;------------------------------------------------------------------------------
|