;/*
;    FreeRTOS V7.5.2 - Copyright (C) 2013 Real Time Engineers Ltd.
;
;
;    ***************************************************************************
;     *                                                                       *
;     *    FreeRTOS tutorial books are available in pdf and paperback.        *
;     *    Complete, revised, and edited pdf reference manuals are also       *
;     *    available.                                                         *
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;     *    for microcontrollers - completely free of charge!                  *
;     *                                                                       *
;     *    >>> See http://www.FreeRTOS.org/Documentation for details. <<<     *
;     *                                                                       *
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;
;
;    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
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;    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
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;    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.
;
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;
;    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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;    http://www.OpenRTOS.com - Commercial support, development, porting,
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;*/

SYS_MODE			EQU		0x1f
SVC_MODE			EQU		0x13
IRQ_MODE			EQU		0x12

	IMPORT  ulCriticalNesting
	IMPORT	pxCurrentTCB
	IMPORT	ulPortTaskHasFPUContext
	IMPORT  ulAsmAPIPriorityMask
	IMPORT	ulICCPMR


	MACRO
	portSAVE_CONTEXT

	; Save the LR and SPSR onto the system mode stack before switching to
	; system mode to save the remaining system mode registers
	SRSDB	sp!, #SYS_MODE
	CPS		#SYS_MODE
	PUSH	{R0-R12, R14}

	; Push the critical nesting count
	LDR		R2, =ulCriticalNesting
	LDR		R1, [R2]
	PUSH	{R1}

	; Does the task have a floating point context that needs saving?  If
	; ulPortTaskHasFPUContext is 0 then no.
	LDR		R2, =ulPortTaskHasFPUContext
	LDR		R3, [R2]
	CMP		R3, #0

	; Save the floating point context, if any
	FMRXNE  R1,  FPSCR
	VPUSHNE {D0-D15}
	VPUSHNE	{D16-D31}
	PUSHNE	{R1}

	; Save ulPortTaskHasFPUContext itself
	PUSH	{R3}

	; Save the stack pointer in the TCB
	LDR		R0, =pxCurrentTCB
	LDR		R1, [R0]
	STR		SP, [R1]

	MEND

; /**********************************************************************/

	MACRO
	portRESTORE_CONTEXT

	; Switch to system mode
	CPS		#SYS_MODE

	; Set the SP to point to the stack of the task being restored.
	LDR		R0, =pxCurrentTCB
	LDR		R1, [R0]
	LDR		SP, [R1]

	; Is there a floating point context to restore?  If the restored
	; ulPortTaskHasFPUContext is zero then no.
	LDR		R0, =ulPortTaskHasFPUContext
	POP		{R1}
	STR		R1, [R0]
	CMP		R1, #0

	; Restore the floating point context, if any
	LDMFDNE SP!, {R0}
	VPOPNE	{D16-D31}
	VPOPNE	{D0-D15}
	VMSRNE  FPSCR, R0

	; Restore the critical section nesting depth
	LDR		R0, =ulCriticalNesting
	POP		{R1}
	STR		R1, [R0]

	; Ensure the priority mask is correct for the critical nesting depth
	LDR		R2, =ulICCPMR
	CMP		R1, #0
	MOVEQ	R4, #255
	LDRNE	R4, =ulAsmAPIPriorityMask
	STR		R4, [r2]

	; Restore all system mode registers other than the SP (which is already
	; being used)
	POP		{R0-R12, R14}

	; Return to the task code, loading CPSR on the way.
	RFEIA	sp!

	MEND

	END

