/* | |
FreeRTOS V6.1.0 - Copyright (C) 2010 Real Time Engineers Ltd. | |
*************************************************************************** | |
* * | |
* If you are: * | |
* * | |
* + New to FreeRTOS, * | |
* + Wanting to learn FreeRTOS or multitasking in general quickly * | |
* + Looking for basic training, * | |
* + Wanting to improve your FreeRTOS skills and productivity * | |
* * | |
* then take a look at the FreeRTOS books - available as PDF or paperback * | |
* * | |
* "Using the FreeRTOS Real Time Kernel - a Practical Guide" * | |
* http://www.FreeRTOS.org/Documentation * | |
* * | |
* A pdf reference manual is also available. Both are usually delivered * | |
* to your inbox within 20 minutes to two hours when purchased between 8am * | |
* and 8pm GMT (although please allow up to 24 hours in case of * | |
* exceptional circumstances). Thank you for your support! * | |
* * | |
*************************************************************************** | |
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 exception 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. See the GNU General Public License for | |
more details. You should have received a copy of the GNU General Public | |
License and the FreeRTOS license exception along with FreeRTOS; if not it | |
can be viewed here: http://www.freertos.org/a00114.html and also obtained | |
by writing to Richard Barry, contact details for whom are available on the | |
FreeRTOS WEB site. | |
1 tab == 4 spaces! | |
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. | |
*/ | |
.global _vPortYield | |
.extern _vTaskSwitchContext | |
.extern uxCriticalNesting | |
_vPortYield: | |
PUSH SR /* Save the SR used by the task.... */ | |
PUSH W0 /* ....then disable interrupts. */ | |
MOV #32, W0 | |
MOV W0, SR | |
PUSH W1 /* Save registers to the stack. */ | |
PUSH.D W2 | |
PUSH.D W4 | |
PUSH.D W6 | |
PUSH.D W8 | |
PUSH.D W10 | |
PUSH.D W12 | |
PUSH W14 | |
PUSH RCOUNT | |
PUSH TBLPAG | |
PUSH CORCON | |
PUSH PSVPAG | |
MOV _uxCriticalNesting, W0 /* Save the critical nesting counter for the task. */ | |
PUSH W0 | |
MOV _pxCurrentTCB, W0 /* Save the new top of stack into the TCB. */ | |
MOV W15, [W0] | |
call _vTaskSwitchContext | |
MOV _pxCurrentTCB, W0 /* Restore the stack pointer for the task. */ | |
MOV [W0], W15 | |
POP W0 /* Restore the critical nesting counter for the task. */ | |
MOV W0, _uxCriticalNesting | |
POP PSVPAG | |
POP CORCON | |
POP TBLPAG | |
POP RCOUNT /* Restore the registers from the stack. */ | |
POP W14 | |
POP.D W12 | |
POP.D W10 | |
POP.D W8 | |
POP.D W6 | |
POP.D W4 | |
POP.D W2 | |
POP.D W0 | |
POP SR | |
return | |
.end |