Subversion Repositories openrisc

;/*

;    FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.

;

;    ***************************************************************************

;    *                                                                         *

;    * If you are:                                                             *

;    *                                                                         *

;    *    + New to FreeRTOS,                                                   *

;    *    + Wanting to learn FreeRTOS or multitasking in general quickly       *

;    *    + Looking for basic training,                                        *

;    *    + Wanting to improve your FreeRTOS skills and productivity           *

;    *                                                                         *

;    * then take a look at the FreeRTOS books - available as PDF or paperback  *

;    *                                                                         *

;    *        "Using the FreeRTOS Real Time Kernel - a Practical Guide"        *

;    *                  http://www.FreeRTOS.org/Documentation                  *

;    *                                                                         *

;    * A pdf reference manual is also available.  Both are usually delivered   *

;    * to your inbox within 20 minutes to two hours when purchased between 8am *

;    * and 8pm GMT (although please allow up to 24 hours in case of            *

;    * exceptional circumstances).  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 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.

;    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.

;*/

        INCLUDE portmacro.inc

        ;The UART interrupt entry point is defined within an assembly wrapper

        ;within this file.  This takes care of the task context saving before it

        ;calls the main handler (vUART_ISRHandler()) which is written in C within

        ;serial.c.  The execution of the handler can unblock tasks that were blocked

        ;waiting for UART events.  Once the handler completes the asm wrapper 

        ;finishes off by        restoring the context of whichever task is now selected to 

        ;enter the RUNNING state (which might now be a different task to that which

        ;was originally interrupted.

        IMPORT vUART_ISRHandler

        EXPORT vUART_ISREntry

        ;/* Interrupt entry must always be in ARM mode. */

        ARM

        AREA    |.text|, CODE, READONLY

vUART_ISREntry

        PRESERVE8

        ; Save the context of the interrupted task.

        portSAVE_CONTEXT

        ; Call the C handler function - defined within serial.c.

        LDR R0, =vUART_ISRHandler

        MOV LR, PC

        BX R0

        ; Finish off by restoring the context of the task that has been chosen to 

        ; run next - which might be a different task to that which was originally

        ; interrupted.

        portRESTORE_CONTEXT

        END