int main( void )
{
#if defined ( __IAR_SYSTEMS_ICC__ )
/* IAR allows init functions in __low_level_init(), but it is run before global
* variables have been initialised, so the following init still needs to be done
* When using GCC, this is done in crt0_GCC.c
*/
extern void platform_init_mcu_infrastructure( void );
extern void platform_init_external_devices( void );
platform_init_mcu_infrastructure( );
platform_init_external_devices( );
#endif /* #elif defined ( __IAR_SYSTEMS_ICC__ ) */ /* Enter the ThreadX kernel. */
tx_kernel_enter( );
return 0;
}
void _start( void )
{
unsigned long ctor_num;
/* Stack pointer is usually set up by boot process, but if program was loaded via jtag in RAM, that might not have happened */
__asm__( " ldr r1, =link_stack_end\n"
" mov sp, r1\n"
);
/* Setup the interrupt vectors address */
SCB->VTOR = (unsigned long) &link_interrupt_vectors_location;
/* Enable CPU Cycle counting */
CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk; /* Global Enable for DWT */
DWT->CYCCNT = 0; /* Reset the counter */
DWT->CTRL |= DWT_CTRL_CYCCNTENA_Msk; /* Enable cycle counter */
/* Copy from flash any code to be run from RAM. Setup .fastcode section first in case init_clocks() needs it */
if ( ( &link_run_from_ram_code_ram_location != &link_run_from_ram_code_flash_location ) && ( link_run_from_ram_code_size != 0 ) )
{
memcpy( &link_run_from_ram_code_ram_location, &link_run_from_ram_code_flash_location, (size_t) link_run_from_ram_code_size );
}
/* Initialise clocks and memory. init_clocks() and init_memory() must NOT depend on globals as global data and bss sections aren't initialised yet */
platform_init_system_clocks();
platform_init_memory();
/* Copy initial values for global variables into RAM */
if ( ( &link_global_data_start != &link_global_data_initial_values ) && ( link_global_data_size != 0 ) )
{
memcpy( &link_global_data_start, &link_global_data_initial_values, (size_t) link_global_data_size );
}
/* BSS segment is for zero initialised elements, so memset it to zero */
memset( &link_bss_location, 0, (size_t) link_bss_size );
#if 0 /* was ifdef DEBUG */
/* This is not a valid way to fill the stack, since it is currently in use - causes a problem in release with debug on - optimisation of active stack overwriting causes hardfault */
memset( &link_stack_location, 0xA5, link_stack_size ); /* Fill stack with pattern to allow checking of stack usage */
#endif /* if 0 */
/*
* Run global C++ constructors if any
*/
/* TODO: make this an unconditional goto?, so that return address stuff doesn't get put on the stack. (what happens if main returns in this case?) */
platform_init_mcu_infrastructure( );
platform_init_external_devices( );
for ( ctor_num = 0; ctor_num < link_constructors_size/sizeof(constructor_ptr_t); ctor_num++ )
{
link_constructors_location[ctor_num]();
}
main( );
/* the main loop has returned - there is now nothing to do - reboot. */
/* Reset request */
SCB->AIRCR = SCB_AIRCR_SYSRESETREQ_Msk | SCB_AIRCR_VECTKEY;
}