blob: 0004790a3692aeb74fea10f62e88b30380db8813 [file] [log] [blame]
/*
FreeRTOS V8.1.1 - Copyright (C) 2014 Real Time Engineers Ltd.
All rights reserved
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
***************************************************************************
* *
* FreeRTOS provides completely free yet professionally developed, *
* robust, strictly quality controlled, supported, and cross *
* platform software that has become a de facto standard. *
* *
* Help yourself get started quickly and support the FreeRTOS *
* project by purchasing a FreeRTOS tutorial book, reference *
* manual, or both from: http://www.FreeRTOS.org/Documentation *
* *
* Thank you! *
* *
***************************************************************************
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. Full license text is available from the following
link: http://www.freertos.org/a00114.html
1 tab == 4 spaces!
***************************************************************************
* *
* Having a problem? Start by reading the FAQ "My application does *
* not run, what could be wrong?" *
* *
* http://www.FreeRTOS.org/FAQHelp.html *
* *
***************************************************************************
http://www.FreeRTOS.org - Documentation, books, training, latest versions,
license and Real Time Engineers Ltd. contact details.
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
including FreeRTOS+Trace - an indispensable productivity tool, a DOS
compatible FAT file system, and our tiny thread aware UDP/IP stack.
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and middleware.
http://www.SafeRTOS.com - High Integrity Systems also provide a safety
engineered and independently SIL3 certified version for use in safety and
mission critical applications that require provable dependability.
1 tab == 4 spaces!
*/
#ifndef PORT_ASM_H
#define PORT_ASM_H
typedef void TCB_t;
extern volatile TCB_t * 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