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/*
FreeRTOS V8.1.0 - 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
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