/* | |
FreeRTOS.org V5.0.4 - Copyright (C) 2003-2008 Richard Barry. | |
This file is part of the FreeRTOS.org distribution. | |
FreeRTOS.org is free software; you can redistribute it and/or modify | |
it under the terms of the GNU General Public License as published by | |
the Free Software Foundation; either version 2 of the License, or | |
(at your option) any later version. | |
FreeRTOS.org 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 | |
along with FreeRTOS.org; if not, write to the Free Software | |
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
A special exception to the GPL can be applied should you wish to distribute | |
a combined work that includes FreeRTOS.org, without being obliged to provide | |
the source code for any proprietary components. See the licensing section | |
of http://www.FreeRTOS.org for full details of how and when the exception | |
can be applied. | |
*************************************************************************** | |
*************************************************************************** | |
* * | |
* SAVE TIME AND MONEY! We can port FreeRTOS.org to your own hardware, * | |
* and even write all or part of your application on your behalf. * | |
* See http://www.OpenRTOS.com for details of the services we provide to * | |
* expedite your project. * | |
* * | |
*************************************************************************** | |
*************************************************************************** | |
Please ensure to read the configuration and relevant port sections of the | |
online documentation. | |
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. | |
*/ | |
#ifndef PORT_ASM_H | |
#define PORT_ASM_H | |
typedef void tskTCB; | |
extern volatile tskTCB * volatile pxCurrentTCB; | |
extern void vTaskSwitchContext( void ); | |
/* | |
* Saves the stack pointer for one task into its TCB, calls | |
* vTaskSwitchContext() to update the TCB being used, then restores the stack | |
* from the new TCB read to run the task. | |
*/ | |
void portSWITCH_CONTEXT( void ); | |
/* | |
* Load the stack pointer from the TCB of the task which is going to be first | |
* to execute. Then force an IRET so the registers and IP are popped off the | |
* stack. | |
*/ | |
void portFIRST_CONTEXT( void ); | |
/* There are slightly different versions depending on whether you are building | |
to include debugger information. If debugger information is used then there | |
are a couple of extra bytes left of the ISR stack (presumably for use by the | |
debugger). The true stack pointer is then stored in the bp register. We add | |
2 to the stack pointer to remove the extra bytes before we restore our context. */ | |
#define portSWITCH_CONTEXT() \ | |
asm { mov ax, seg pxCurrentTCB } \ | |
asm { mov ds, ax } \ | |
asm { les bx, pxCurrentTCB } /* Save the stack pointer into the TCB. */ \ | |
asm { mov es:0x2[ bx ], ss } \ | |
asm { mov es:[ bx ], sp } \ | |
asm { call far ptr vTaskSwitchContext } /* Perform the switch. */ \ | |
asm { mov ax, seg pxCurrentTCB } /* Restore the stack pointer from the TCB. */ \ | |
asm { mov ds, ax } \ | |
asm { les bx, dword ptr pxCurrentTCB } \ | |
asm { mov ss, es:[ bx + 2 ] } \ | |
asm { mov sp, es:[ bx ] } | |
#define portFIRST_CONTEXT() \ | |
__asm { mov ax, seg pxCurrentTCB } \ | |
__asm { mov ds, ax } \ | |
__asm { les bx, dword ptr pxCurrentTCB } \ | |
__asm { mov ss, es:[ bx + 2 ] } \ | |
__asm { mov sp, es:[ bx ] } \ | |
__asm { pop bp } \ | |
__asm { pop di } \ | |
__asm { pop si } \ | |
__asm { pop ds } \ | |
__asm { pop es } \ | |
__asm { pop dx } \ | |
__asm { pop cx } \ | |
__asm { pop bx } \ | |
__asm { pop ax } \ | |
__asm { iret } | |
#endif | |