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/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT 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
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* Imports the Cortex-Mx configuration headers.
*/
#define _FROM_ASM_
#include "chconf.h"
#include "chcore.h"
CONTEXT_OFFSET EQU 12
SCB_ICSR EQU 0xE000ED04
ICSR_PENDSVSET EQU 0x10000000
PRESERVE8
THUMB
AREA |.text|, CODE, READONLY
IMPORT chThdExit
IMPORT chSchDoReschedule
#if CH_DBG_SYSTEM_STATE_CHECK
IMPORT dbg_check_unlock
IMPORT dbg_check_lock
#endif
/*
* Performs a context switch between two threads.
*/
EXPORT _port_switch
_port_switch PROC
push {r4, r5, r6, r7, r8, r9, r10, r11, lr}
#if CORTEX_USE_FPU
vpush {s16-s31}
#endif
str sp, [r1, #CONTEXT_OFFSET]
ldr sp, [r0, #CONTEXT_OFFSET]
#if CORTEX_USE_FPU
vpop {s16-s31}
#endif
pop {r4, r5, r6, r7, r8, r9, r10, r11, pc}
ENDP
/*
* Start a thread by invoking its work function.
* If the work function returns @p chThdExit() is automatically invoked.
*/
EXPORT _port_thread_start
_port_thread_start PROC
#if CH_DBG_SYSTEM_STATE_CHECK
bl dbg_check_unlock
#endif
#if CORTEX_SIMPLIFIED_PRIORITY
cpsie i
#else
movs r3, #CORTEX_BASEPRI_DISABLED
msr BASEPRI, r3
#endif
mov r0, r5
blx r4
bl chThdExit
ENDP
/*
* Post-IRQ switch code.
* Exception handlers return here for context switching.
*/
EXPORT _port_switch_from_isr
EXPORT _port_exit_from_isr
_port_switch_from_isr PROC
#if CH_DBG_SYSTEM_STATE_CHECK
bl dbg_check_lock
#endif
bl chSchDoReschedule
#if CH_DBG_SYSTEM_STATE_CHECK
bl dbg_check_unlock
#endif
_port_exit_from_isr
#if CORTEX_SIMPLIFIED_PRIORITY
mov r3, #SCB_ICSR :AND: 0xFFFF
movt r3, #SCB_ICSR :SHR: 16
mov r2, #ICSR_PENDSVSET
str r2, [r3, #0]
cpsie i
waithere b waithere
#else
svc #0
#endif
ENDP
END
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