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|
;
;/*
; FreeRTOS V8.2.3 - Copyright (C) 2015 Real Time Engineers Ltd.
; All rights reserved
;
;
; ***************************************************************************
; * *
; * FreeRTOS tutorial books are available in pdf and paperback. *
; * Complete, revised, and edited pdf reference manuals are also *
; * available. *
; * *
; * Purchasing FreeRTOS documentation will not only help you, by *
; * ensuring you get running as quickly as possible and with an *
; * in-depth knowledge of how to use FreeRTOS, it will also help *
; * the FreeRTOS project to continue with its mission of providing *
; * professional grade, cross platform, de facto standard solutions *
; * for microcontrollers - completely free of charge! *
; * *
; * >>> See http://www.FreeRTOS.org/Documentation for details. <<< *
; * *
; * Thank you for using FreeRTOS, and thank you for your support! *
; * *
; ***************************************************************************
;
;
; This file is part of the FreeRTOS distribution.
;
; FreeRTOS is free software; you can redistribute it and/or modify it under
; the terms of the GNU General Public License (version 2) as published by the
; Free Software Foundation AND MODIFIED BY the FreeRTOS exception.
; >>>NOTE<<< The modification to the GPL is included to allow you to
; distribute a combined work that includes FreeRTOS without being obliged to
; provide the source code for proprietary components outside of the FreeRTOS
; kernel. FreeRTOS is distributed in the hope that it will be useful, but
; WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
; or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
; more details. You should have received a copy of the GNU General Public
; License and the FreeRTOS license exception along with FreeRTOS; if not it
; can be viewed here: http://www.freertos.org/a00114.html and also obtained
; by writing to Richard Barry, contact details for whom are available on the
; FreeRTOS WEB site.
;
; 1 tab == 4 spaces!
;
; http://www.FreeRTOS.org - Documentation, latest information, license and
; contact details.
;
; http://www.SafeRTOS.com - A version that is certified for use in safety
; critical systems.
;
; http://www.OpenRTOS.com - Commercial support, development, porting,
; licensing and training services.
;*/
; * The definition of the "register test" tasks, as described at the top of
; * main.c
.include data_model.h
.global xTaskIncrementTick
.global vTaskSwitchContext
.global vPortSetupTimerInterrupt
.global pxCurrentTCB
.global usCriticalNesting
.def vPortPreemptiveTickISR
.def vPortCooperativeTickISR
.def vPortYield
.def xPortStartScheduler
;-----------------------------------------------------------
portSAVE_CONTEXT .macro
;Save the remaining registers.
pushm_x #12, r15
mov.w &usCriticalNesting, r14
push_x r14
mov_x &pxCurrentTCB, r12
mov_x sp, 0( r12 )
.endm
;-----------------------------------------------------------
portRESTORE_CONTEXT .macro
mov_x &pxCurrentTCB, r12
mov_x @r12, sp
pop_x r15
mov.w r15, &usCriticalNesting
popm_x #12, r15
nop
pop.w sr
nop
ret_x
.endm
;-----------------------------------------------------------
;*
;* The RTOS tick ISR.
;*
;* If the cooperative scheduler is in use this simply increments the tick
;* count.
;*
;* If the preemptive scheduler is in use a context switch can also occur.
;*/
.text
.align 2
vPortPreemptiveTickISR: .asmfunc
; The sr is not saved in portSAVE_CONTEXT() because vPortYield() needs
;to save it manually before it gets modified (interrupts get disabled).
push.w sr
portSAVE_CONTEXT
call_x #xTaskIncrementTick
call_x #vTaskSwitchContext
portRESTORE_CONTEXT
.endasmfunc
;-----------------------------------------------------------
.align 2
vPortCooperativeTickISR: .asmfunc
; The sr is not saved in portSAVE_CONTEXT() because vPortYield() needs
;to save it manually before it gets modified (interrupts get disabled).
push.w sr
portSAVE_CONTEXT
call_x #xTaskIncrementTick
portRESTORE_CONTEXT
.endasmfunc
;-----------------------------------------------------------
;
; Manual context switch called by the portYIELD() macro.
;
.align 2
vPortYield: .asmfunc
; The sr needs saving before it is modified.
push.w sr
; Now the SR is stacked we can disable interrupts.
dint
nop
; Save the context of the current task.
portSAVE_CONTEXT
; Select the next task to run.
call_x #vTaskSwitchContext
; Restore the context of the new task.
portRESTORE_CONTEXT
.endasmfunc
;-----------------------------------------------------------
;
; Start off the scheduler by initialising the RTOS tick timer, then restoring
; the context of the first task.
;
.align 2
xPortStartScheduler: .asmfunc
; Setup the hardware to generate the tick. Interrupts are disabled
; when this function is called.
call_x #vPortSetupTimerInterrupt
; Restore the context of the first task that is going to run.
portRESTORE_CONTEXT
.endasmfunc
;-----------------------------------------------------------
.end
|
