| /* | |
| FreeRTOS V8.0.0:rc1 - 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! | |
| */ | |
| 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 | |