;/* | |
; FreeRTOS.org V5.1.1 - Copyright (C) 2003-2008 Richard Barry. | |
; | |
; This file is part of the FreeRTOS.org distribution. | |
; | |
; FreeRTOS.org is free software; you can redistribute it and/or modify | |
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; FreeRTOS.org 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 | |
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; Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
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; A special exception to the GPL can be applied should you wish to distribute | |
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; *************************************************************************** | |
; *************************************************************************** | |
; * * | |
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; *************************************************************************** | |
; *************************************************************************** | |
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; Please ensure to read the configuration and relevant port sections of the | |
; online documentation. | |
; | |
; http://www.FreeRTOS.org - Documentation, latest information, license and | |
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; http://www.SafeRTOS.com - A version that is certified for use in safety | |
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;*/ | |
IMPORT ulCriticalNesting ; | |
IMPORT pxCurrentTCB ; | |
MACRO | |
portRESTORE_CONTEXT | |
LDR R0, =pxCurrentTCB ; Set the LR to the task stack. The location was... | |
LDR R0, [R0] ; ... stored in pxCurrentTCB | |
LDR LR, [R0] | |
LDR R0, =ulCriticalNesting ; The critical nesting depth is the first item on... | |
LDMFD LR!, {R1} ; ...the stack. Load it into the ulCriticalNesting var. | |
STR R1, [R0] ; | |
LDMFD LR!, {R0} ; Get the SPSR from the stack. | |
MSR SPSR_cxsf, R0 ; | |
LDMFD LR, {R0-R14}^ ; Restore all system mode registers for the task. | |
NOP ; | |
LDR LR, [LR, #+60] ; Restore the return address | |
; And return - correcting the offset in the LR to obtain ... | |
SUBS PC, LR, #4 ; ...the correct address. | |
MEND | |
; /**********************************************************************/ | |
MACRO | |
portSAVE_CONTEXT | |
STMDB SP!, {R0} ; Store R0 first as we need to use it. | |
STMDB SP,{SP}^ ; Set R0 to point to the task stack pointer. | |
NOP ; | |
SUB SP, SP, #4 ; | |
LDMIA SP!,{R0} ; | |
STMDB R0!, {LR} ; Push the return address onto the stack. | |
MOV LR, R0 ; Now we have saved LR we can use it instead of R0. | |
LDMIA SP!, {R0} ; Pop R0 so we can save it onto the system mode stack. | |
STMDB LR,{R0-LR}^ ; Push all the system mode registers onto the task stack. | |
NOP ; | |
SUB LR, LR, #60 ; | |
MRS R0, SPSR ; Push the SPSR onto the task stack. | |
STMDB LR!, {R0} ; | |
LDR R0, =ulCriticalNesting ; | |
LDR R0, [R0] ; | |
STMDB LR!, {R0} ; | |
LDR R0, =pxCurrentTCB ; Store the new top of stack for the task. | |
LDR R1, [R0] ; | |
STR LR, [R1] ; | |
MEND | |
END |