mirror of
https://github.com/FreeRTOS/FreeRTOS-Kernel.git
synced 2025-04-19 21:11:57 -04:00
126 lines
5.7 KiB
C
126 lines
5.7 KiB
C
/*
|
|
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
|
|
|