Subversion Repositories openrisc_2011-10-31

;/*
;    FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.
;
;    ***************************************************************************
;    *                                                                         *
;    * If you are:                                                             *
;    *                                                                         *
;    *    + New to FreeRTOS,                                                   *
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;    *        "Using the FreeRTOS Real Time Kernel - a Practical Guide"        *
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;    *                                                                         *
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;
;    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 exception 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.
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;    FreeRTOS WEB site.
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;*/

        RSEG ICODE:CODE
        CODE32

        EXTERN vPortPreemptiveTick
        EXTERN vTaskSwitchContext

        PUBLIC vPortYieldProcessor
        PUBLIC vPortStartFirstTask

#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.



        END