/* | |
FreeRTOS V8.0.1 - 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! | |
*/ | |
EXTERN pxCurrentTCB | |
EXTERN ulCriticalNesting | |
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
; Context save and restore macro definitions | |
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
portSAVE_CONTEXT MACRO | |
; Push R0 as we are going to use the register. | |
STMDB SP!, {R0} | |
; Set R0 to point to the task stack pointer. | |
STMDB SP, {SP}^ | |
NOP | |
SUB SP, SP, #4 | |
LDMIA SP!, {R0} | |
; Push the return address onto the stack. | |
STMDB R0!, {LR} | |
; Now we have saved LR we can use it instead of R0. | |
MOV LR, R0 | |
; Pop R0 so we can save it onto the system mode stack. | |
LDMIA SP!, {R0} | |
; Push all the system mode registers onto the task stack. | |
STMDB LR, {R0-LR}^ | |
NOP | |
SUB LR, LR, #60 | |
; Push the SPSR onto the task stack. | |
MRS R0, SPSR | |
STMDB LR!, {R0} | |
LDR R0, =ulCriticalNesting | |
LDR R0, [R0] | |
STMDB LR!, {R0} | |
; Store the new top of stack for the task. | |
LDR R1, =pxCurrentTCB | |
LDR R0, [R1] | |
STR LR, [R0] | |
ENDM | |
portRESTORE_CONTEXT MACRO | |
; Set the LR to the task stack. | |
LDR R1, =pxCurrentTCB | |
LDR R0, [R1] | |
LDR LR, [R0] | |
; The critical nesting depth is the first item on the stack. | |
; Load it into the ulCriticalNesting variable. | |
LDR R0, =ulCriticalNesting | |
LDMFD LR!, {R1} | |
STR R1, [R0] | |
; Get the SPSR from the stack. | |
LDMFD LR!, {R0} | |
MSR SPSR_cxsf, R0 | |
; Restore all system mode registers for the task. | |
LDMFD LR, {R0-R14}^ | |
NOP | |
; Restore the return address. | |
LDR LR, [LR, #+60] | |
; And return - correcting the offset in the LR to obtain the | |
; correct address. | |
SUBS PC, LR, #4 | |
ENDM | |