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/*
ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio.
This file is part of ChibiOS.
ChibiOS 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 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/>.
*/
/**
* @file GCC/crt0.s
* @brief Generic PowerPC startup file for GCC.
*
* @addtogroup PPC_GCC_CORE
* @{
*/
/*===========================================================================*/
/* Module constants. */
/*===========================================================================*/
#if !defined(FALSE) || defined(__DOXYGEN__)
#define FALSE 0
#endif
#if !defined(TRUE) || defined(__DOXYGEN__)
#define TRUE 1
#endif
/*===========================================================================*/
/* Module pre-compile time settings. */
/*===========================================================================*/
/**
* @brief Stack segments initialization switch.
*/
#if !defined(CRT0_STACKS_FILL_PATTERN) || defined(__DOXYGEN__)
#define CRT0_STACKS_FILL_PATTERN 0x55555555
#endif
/**
* @brief Stack segments initialization switch.
*/
#if !defined(CRT0_INIT_STACKS) || defined(__DOXYGEN__)
#define CRT0_INIT_STACKS TRUE
#endif
/**
* @brief DATA segment initialization switch.
*/
#if !defined(CRT0_INIT_DATA) || defined(__DOXYGEN__)
#define CRT0_INIT_DATA TRUE
#endif
/**
* @brief BSS segment initialization switch.
*/
#if !defined(CRT0_INIT_BSS) || defined(__DOXYGEN__)
#define CRT0_INIT_BSS TRUE
#endif
/**
* @brief Constructors invocation switch.
*/
#if !defined(CRT0_CALL_CONSTRUCTORS) || defined(__DOXYGEN__)
#define CRT0_CALL_CONSTRUCTORS TRUE
#endif
/**
* @brief Destructors invocation switch.
*/
#if !defined(CRT0_CALL_DESTRUCTORS) || defined(__DOXYGEN__)
#define CRT0_CALL_DESTRUCTORS TRUE
#endif
/*===========================================================================*/
/* Code section. */
/*===========================================================================*/
#if !defined(__DOXYGEN__)
.section .crt0, "ax"
.align 2
.globl _boot_address
.type _boot_address, @function
_boot_address:
/* Stack setup.*/
lis %r1, __process_stack_end__@h
ori %r1, %r1, __process_stack_end__@l
li %r0, 0
stwu %r0, -8(%r1)
/* Small sections registers initialization.*/
lis %r2, __sdata2_start__@h
ori %r2, %r2, __sdata2_start__@l
lis %r13, __sdata_start__@h
ori %r13, %r13, __sdata_start__@l
/* Early initialization.*/
bl __early_init
#if CRT0_INIT_STACKS == TRUE
/* Stacks fill pattern.*/
lis %r7, CRT0_STACKS_FILL_PATTERN@h
ori %r7, %r7, CRT0_STACKS_FILL_PATTERN@l
/* IRQ Stack initialization. Note, the architecture does not use this
stack, the size is usually zero. An OS can have special SW handling
and require this. A 4 bytes alignment is assmend and required.*/
lis %r4, __irq_stack_base__@h
ori %r4, %r4, __irq_stack_base__@l
lis %r5, __irq_stack_end__@h
ori %r5, %r5, __irq_stack_end__@l
.irqsloop:
cmpl cr0, %r4, %r5
bge cr0, .irqsend
stw %r7, 0(%r4)
addi %r4, %r4, 4
b .irqsloop
.irqsend:
/* Process Stack initialization. Note, does not overwrite the already
written EABI frame. A 4 bytes alignment is assmend and required.*/
lis %r4, __process_stack_base__@h
ori %r4, %r4, __process_stack_base__@l
lis %r5, (__process_stack_end__ - 8)@h
ori %r5, %r5, (__process_stack_end__ - 8)@l
.prcsloop:
cmpl cr0, %r4, %r5
bge cr0, .prcsend
stw %r7, 0(%r4)
addi %r4, %r4, 4
b .prcsloop
.prcsend:
#endif
#if CRT0_INIT_BSS == TRUE
/* BSS clearing.*/
lis %r4, __bss_start__@h
ori %r4, %r4, __bss_start__@l
lis %r5, __bss_end__@h
ori %r5, %r5, __bss_end__@l
li %r7, 0
.bssloop:
cmpl cr0, %r4, %r5
bge cr0, .bssend
stw %r7, 0(%r4)
addi %r4, %r4, 4
b .bssloop
.bssend:
#endif
#if CRT0_INIT_DATA == TRUE
/* DATA initialization.*/
lis %r4, __romdata_start__@h
ori %r4, %r4, __romdata_start__@l
lis %r5, __data_start__@h
ori %r5, %r5, __data_start__@l
lis %r6, __data_end__@h
ori %r6, %r6, __data_end__@l
.dataloop:
cmpl cr0, %r5, %r6
bge cr0, .dataend
lwz %r7, 0(%r4)
addi %r4, %r4, 4
stw %r7, 0(%r5)
addi %r5, %r5, 4
b .dataloop
.dataend:
#endif
/* Late initialization.*/
bl __late_init
#if CRT0_CALL_CONSTRUCTORS == TRUE
/* Constructors invocation.*/
lis %r4, __init_array_start@h
ori %r4, %r4, __init_array_start@l
lis %r5, __init_array_end@h
ori %r5, %r5, __init_array_end@l
.iniloop:
cmplw %cr0, %r4, %r5
bge %cr0, .iniend
lwz %r6, 0(%r4)
mtctr %r6
addi %r4, %r4, 4
bctrl
b .iniloop
.iniend:
#endif
/* Main program invocation.*/
bl main
#if CRT0_CALL_DESTRUCTORS == TRUE
/* Destructors invocation.*/
lis %r4, __fini_array_start@h
ori %r4, %r4, __fini_array_start@l
lis %r5, __fini_array_end@h
ori %r5, %r5, __fini_array_end@l
.finiloop:
cmplw %cr0, %r4, %r5
bge %cr0, .finiend
lwz %r6, 0(%r4)
mtctr %r6
addi %r4, %r4, 4
bctrl
b .finiloop
.finiend:
#endif
/* Branching to the defined exit handler.*/
b __default_exit
/* Default main exit code, infinite loop.*/
.weak __default_exit
.globl __default_exit
.type __default_exit, @function
__default_exit:
b __default_exit
/* Default early initialization code, none.*/
.weak __early_init
.globl __early_init
.type __early_init, @function
__early_init:
blr
/* Default late initialization code, none.*/
.weak __late_init
.globl __late_init
.type __late_init, @function
__late_init:
blr
#endif /* !defined(__DOXYGEN__) */
/** @} */
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