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/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
/*----------------------------------------------------------------------------
* Copyright (c) 1999-2009 KEIL, 2009-2013 ARM Germany GmbH
* All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*---------------------------------------------------------------------------*/
.file "HAL_CM4.S"
.syntax unified
/*----------------------------------------------------------------------------
* Functions
*---------------------------------------------------------------------------*/
.thumb
.section ".text"
.align 2
/*--------------------------- os_set_env ------------------------------------*/
# void os_set_env (void);
#
# Called to switch to privileged or unprivileged thread mode. The variable
# 'os_flags' contains the CONTROL bit LSB to set the device into the
# proper mode. We also use PSP so we set bit 1 (the SPSEL bit) to 1.
#
.thumb_func
.type os_set_env, %function
.global os_set_env
os_set_env:
.fnstart
.cantunwind
MOV R0,SP /* Copy MSP to PSP */
MSR PSP,R0
LDR R0,=os_flags
LDRB R0,[R0]
ADDS R0, R0, #2
MSR CONTROL,R0
ISB
BX LR
.fnend
.size os_set_env, .-os_set_env
/*--------------------------- os_set_env ------------------------------------*/
/*--------------------------- os_arch_init_task_stack------------------------*/
# void os_arch_init_task_stack(os_stack_t *sf);
# NOTE: This function only stores R4 through R11 on stack. The reason we do
# this is that the application may have stored some values in some of the
# registers and we want to preserve those values (position independent code
# is a good example). The other registers are handled in the C startup code.
.thumb_func
.type os_arch_init_task_stack, %function
.global os_arch_init_task_stack
os_arch_init_task_stack:
.fnstart
STMIA R0,{R4-R11}
BX LR
.fnend
.size os_arch_init_task_stack, .-os_arch_init_task_stack
/*--------------------------- os_set_env ------------------------------------*/
/*-------------------------- SVC_Handler ------------------------------------*/
# void SVC_Handler (void);
.thumb_func
.type SVC_Handler, %function
.global SVC_Handler
SVC_Handler:
.fnstart
.cantunwind
MRS R0,PSP /* Read PSP */
LDR R1,[R0,#24] /* Read Saved PC from Stack */
LDRB R1,[R1,#-2] /* Load SVC Number */
CBNZ R1,SVC_User
LDM R0,{R0-R3,R12} /* Read R0-R3,R12 from stack */
PUSH {R4,LR} /* Save EXC_RETURN */
BLX R12 /* Call SVC Function */
POP {R4,LR} /* Restore EXC_RETURN */
MRS R12,PSP /* Read PSP */
STM R12,{R0-R2} /* Store return values */
BX LR /* Return from interrupt */
/*------------------- User SVC ------------------------------*/
SVC_User:
PUSH {R4,LR} /* Save EXC_RETURN */
LDR R2,=SVC_Count
LDR R2,[R2]
CMP R1,R2
BHI SVC_Done /* Overflow */
LDR R4,=SVC_Table-4
LDR R4,[R4,R1,LSL #2] /* Load SVC Function Address */
LDM R0,{R0-R3,R12} /* Read R0-R3,R12 from stack */
BLX R4 /* Call SVC Function */
MRS R12,PSP
STM R12,{R0-R3} /* Function return values */
SVC_Done:
POP {R4,LR} /* Restore EXC_RETURN */
BX LR /* Return from interrupt */
.fnend
.size SVC_Handler, .-SVC_Handler
/*-------------------------- PendSV_Handler ---------------------------------*/
# void PendSV_Handler (void);
.thumb_func
.type PendSV_Handler, %function
.global PendSV_Handler
PendSV_Handler:
.fnstart
.cantunwind
LDR R3,=g_os_run_list /* Get highest priority task ready to run */
LDR R2,[R3] /* Store in R2 */
LDR R3,=g_current_task /* Get current task */
LDR R1,[R3] /* Current task in R1 */
CMP R1,R2
IT EQ
BXEQ LR /* RETI, no task switch */
MRS R12,PSP /* Read PSP */
STMDB R12!,{R4-R11} /* Save Old context */
STR R12,[R1,#0] /* Update stack pointer in current task */
STR R2,[R3] /* g_current_task = highest ready */
LDR R12,[R2,#0] /* get stack pointer of task we will start */
LDMIA R12!,{R4-R11} /* Restore New Context */
MSR PSP,R12 /* Write PSP */
BX LR /* Return to Thread Mode */
.fnend
.size PendSV_Handler, .-PendSV_Handler
/*-------------------------- SysTick_Handler --------------------------------*/
# void SysTick_Handler (void);
.thumb_func
.type SysTick_Handler, %function
.global SysTick_Handler
SysTick_Handler:
.fnstart
.cantunwind
PUSH {R4,LR} /* Save EXC_RETURN */
BL timer_handler
POP {R4,LR} /* Restore EXC_RETURN */
BX LR
.fnend
.size SysTick_Handler, .-SysTick_Handler
/*-------------------------- Defalt IRQ --------------------------------*/
.thumb_func
.type os_default_irq_asm, %function
.global os_default_irq_asm
os_default_irq_asm:
.fnstart
.cantunwind
/*
* LR = 0xfffffff9 if we were using MSP as SP
* LR = 0xfffffffd if we were using PSP as SP
*/
TST LR,#4
ITE EQ
MRSEQ R3,MSP
MRSNE R3,PSP
PUSH {R3-R11,LR}
MOV R0, SP
BL os_default_irq
POP {R3-R11,LR} /* Restore EXC_RETURN */
BX LR
.fnend
.size os_default_irq_asm, .-os_default_irq_asm
/*
* Prevent libgcc unwind stuff from getting pulled in.
*/
.section ".data"
.global __aeabi_unwind_cpp_pr0
__aeabi_unwind_cpp_pr0:
.end
/*----------------------------------------------------------------------------
* end of file
*---------------------------------------------------------------------------*/
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