blob: eea1df0e20671c7c139d84269152eba595fcef87 [file] [log] [blame]
;/*
; FreeRTOS V8.1.1 - Copyright (C) 2014 Real Time Engineers Ltd.
; All rights reserved
;
;
; ***************************************************************************
; * *
; * FreeRTOS tutorial books are available in pdf and paperback. *
; * Complete, revised, and edited pdf reference manuals are also *
; * available. *
; * *
; * Purchasing FreeRTOS documentation will not only help you, by *
; * ensuring you get running as quickly as possible and with an *
; * in-depth knowledge of how to use FreeRTOS, it will also help *
; * the FreeRTOS project to continue with its mission of providing *
; * professional grade, cross platform, de facto standard solutions *
; * for microcontrollers - completely free of charge! *
; * *
; * >>> See http://www.FreeRTOS.org/Documentation for details. <<< *
; * *
; * Thank you for using FreeRTOS, and 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 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. 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.
;*/
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
; 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
POPNE {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