/* | |
FreeRTOS V9.0.0 - Copyright (C) 2016 Real Time Engineers Ltd. | |
All rights reserved | |
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. | |
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 on the following | |
link: http://www.freertos.org/a00114.html | |
*************************************************************************** | |
* * | |
* FreeRTOS provides completely free yet professionally developed, * | |
* robust, strictly quality controlled, supported, and cross * | |
* platform software that is more than just the market leader, it * | |
* is the industry's de facto standard. * | |
* * | |
* Help yourself get started quickly while simultaneously helping * | |
* to support the FreeRTOS project by purchasing a FreeRTOS * | |
* tutorial book, reference manual, or both: * | |
* http://www.FreeRTOS.org/Documentation * | |
* * | |
*************************************************************************** | |
http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading | |
the FAQ page "My application does not run, what could be wrong?". Have you | |
defined configASSERT()? | |
http://www.FreeRTOS.org/support - In return for receiving this top quality | |
embedded software for free we request you assist our global community by | |
participating in the support forum. | |
http://www.FreeRTOS.org/training - Investing in training allows your team to | |
be as productive as possible as early as possible. Now you can receive | |
FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers | |
Ltd, and the world's leading authority on the world's leading RTOS. | |
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.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate. | |
Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS. | |
http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High | |
Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS | |
licenses offer ticketed support, indemnification and commercial 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! | |
*/ | |
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. */ | |
#ifdef DEBUG_BUILD | |
#pragma aux portSWITCH_CONTEXT = "mov ax, seg pxCurrentTCB" \ | |
"mov ds, ax" \ | |
"les bx, pxCurrentTCB" /* Save the stack pointer into the TCB. */ \ | |
"mov es:0x2[ bx ], ss" \ | |
"mov es:[ bx ], sp" \ | |
"call vTaskSwitchContext" /* Perform the switch. */ \ | |
"mov ax, seg pxCurrentTCB" /* Restore the stack pointer from the TCB. */ \ | |
"mov ds, ax" \ | |
"les bx, dword ptr pxCurrentTCB" \ | |
"mov ss, es:[ bx + 2 ]" \ | |
"mov sp, es:[ bx ]" \ | |
"mov bp, sp" /* Prepair the bp register for the restoration of the SP in the compiler generated portion of the ISR */ \ | |
"add bp, 0x0002" | |
#pragma aux portFIRST_CONTEXT = "mov ax, seg pxCurrentTCB" \ | |
"mov ds, ax" \ | |
"les bx, dword ptr pxCurrentTCB" \ | |
"mov ss, es:[ bx + 2 ]" \ | |
"mov sp, es:[ bx ]" \ | |
"add sp, 0x0002" /* Remove the extra bytes that exist in debug builds before restoring the context. */ \ | |
"pop ax" \ | |
"pop ax" \ | |
"pop es" \ | |
"pop ds" \ | |
"popa" \ | |
"iret" | |
#else | |
#pragma aux portSWITCH_CONTEXT = "mov ax, seg pxCurrentTCB" \ | |
"mov ds, ax" \ | |
"les bx, pxCurrentTCB" /* Save the stack pointer into the TCB. */ \ | |
"mov es:0x2[ bx ], ss" \ | |
"mov es:[ bx ], sp" \ | |
"call vTaskSwitchContext" /* Perform the switch. */ \ | |
"mov ax, seg pxCurrentTCB" /* Restore the stack pointer from the TCB. */ \ | |
"mov ds, ax" \ | |
"les bx, dword ptr pxCurrentTCB" \ | |
"mov ss, es:[ bx + 2 ]" \ | |
"mov sp, es:[ bx ]" | |
#pragma aux portFIRST_CONTEXT = "mov ax, seg pxCurrentTCB" \ | |
"mov ds, ax" \ | |
"les bx, dword ptr pxCurrentTCB" \ | |
"mov ss, es:[ bx + 2 ]" \ | |
"mov sp, es:[ bx ]" \ | |
"pop ax" \ | |
"pop ax" \ | |
"pop es" \ | |
"pop ds" \ | |
"popa" \ | |
"iret" | |
#endif | |