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/*
ChibiOS - Copyright (C) 2006..2018 Giovanni Di Sirio
Licensed 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.
*/
/**
* @file crt0.S
* @brief Generic ARM startup file.
*
* @addtogroup ARM_GCC_STARTUP
* @{
*/
#if !defined(__DOXYGEN__)
.set MODE_USR, 0x10
.set MODE_FIQ, 0x11
.set MODE_IRQ, 0x12
.set MODE_SVC, 0x13
.set MODE_ABT, 0x17
.set MODE_UND, 0x1B
.set MODE_SYS, 0x1F
.set I_BIT, 0x80
.set F_BIT, 0x40
.text
.code 32
.balign 4
/*
* Reset handler.
*/
.global Reset_Handler
Reset_Handler:
/*
* Stack pointers initialization.
*/
ldr r0, =__stacks_end__
/* Undefined */
msr CPSR_c, #MODE_UND | I_BIT | F_BIT
mov sp, r0
ldr r1, =__und_stack_size__
sub r0, r0, r1
/* Abort */
msr CPSR_c, #MODE_ABT | I_BIT | F_BIT
mov sp, r0
ldr r1, =__abt_stack_size__
sub r0, r0, r1
/* FIQ */
msr CPSR_c, #MODE_FIQ | I_BIT | F_BIT
mov sp, r0
ldr r1, =__fiq_stack_size__
sub r0, r0, r1
/* IRQ */
msr CPSR_c, #MODE_IRQ | I_BIT | F_BIT
mov sp, r0
ldr r1, =__irq_stack_size__
sub r0, r0, r1
/* Supervisor */
msr CPSR_c, #MODE_SVC | I_BIT | F_BIT
mov sp, r0
ldr r1, =__svc_stack_size__
sub r0, r0, r1
/* System */
msr CPSR_c, #MODE_SYS | I_BIT | F_BIT
mov sp, r0
// ldr r1, =__sys_stack_size__
// sub r0, r0, r1
/*
* Early initialization.
*/
bl __early_init
/*
* Data initialization.
* NOTE: It assumes that the DATA size is a multiple of 4.
*/
ldr r1, =_textdata
ldr r2, =_data
ldr r3, =_edata
dataloop:
cmp r2, r3
ldrlo r0, [r1], #4
strlo r0, [r2], #4
blo dataloop
/*
* BSS initialization.
* NOTE: It assumes that the BSS size is a multiple of 4.
*/
mov r0, #0
ldr r1, =_bss_start
ldr r2, =_bss_end
bssloop:
cmp r1, r2
strlo r0, [r1], #4
blo bssloop
/*
* Late initialization.
*/
bl __core_init
bl __late_init
/*
* Main program invocation.
*/
bl main
b __default_exit
#endif /* !defined(__DOXYGEN__) */
/** @} */
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