/**
*
* @brief Initializes nanokernel data structures
*
* This routine initializes various nanokernel data structures, including
* the background (or idle) task and any architecture-specific initialization.
*
* Note that all fields of "_nanokernel" are set to zero on entry, which may
* be all the initialization many of them require.
*
* @return N/A
*/
static void nano_init(struct tcs *dummyOutContext)
{
/*
* Initialize the current execution thread to permit a level of debugging
* output if an exception should happen during nanokernel initialization.
* However, don't waste effort initializing the fields of the dummy thread
* beyond those needed to identify it as a dummy thread.
*/
_nanokernel.current = dummyOutContext;
/*
* Do not insert dummy execution context in the list of fibers, so that it
* does not get scheduled back in once context-switched out.
*/
dummyOutContext->link = (struct tcs *)NULL;
dummyOutContext->flags = FIBER | ESSENTIAL;
dummyOutContext->prio = 0;
/*
* The interrupt library needs to be initialized early since a series of
* handlers are installed into the interrupt table to catch spurious
* interrupts. This must be performed before other nanokernel subsystems
* install bonafide handlers, or before hardware device drivers are
* initialized.
*/
_IntLibInit();
/*
* Initialize the thread control block (TCS) for the main task (either
* background or idle task). The entry point for this thread is '_main'.
*/
_nanokernel.task = (struct tcs *) main_task_stack;
_new_thread(main_task_stack, /* pStackMem */
CONFIG_MAIN_STACK_SIZE, /* stackSize */
(_thread_entry_t)_main, /* pEntry */
(_thread_arg_t)0, /* parameter1 */
(_thread_arg_t)0, /* parameter2 */
(_thread_arg_t)0, /* parameter3 */
-1, /* priority */
0 /* options */
);
/* indicate that failure of this task may be fatal to the entire system */
_nanokernel.task->flags |= ESSENTIAL;
initialize_nano_timeouts();
/* perform any architecture-specific initialization */
nanoArchInit();
}
void _PrepC(void)
{
#ifdef CONFIG_INIT_STACKS
init_stacks();
#endif
/*
* Set PSP and use it to boot without using MSP, so that it
* gets set to _interrupt_stack during initialization.
*/
set_and_switch_to_psp();
relocate_vector_table();
enable_floating_point();
_bss_zero();
_data_copy();
#ifdef CONFIG_BOOT_TIME_MEASUREMENT
__start_time_stamp = 0U;
#endif
_IntLibInit();
_Cstart();
CODE_UNREACHABLE;
}
/**
*
* @brief Initializes kernel data structures
*
* This routine initializes various kernel data structures, including
* the init and idle threads and any architecture-specific initialization.
*
* Note that all fields of "_kernel" are set to zero on entry, which may
* be all the initialization many of them require.
*
* @return N/A
*/
static void prepare_multithreading(struct k_thread *dummy_thread)
{
#ifdef CONFIG_ARCH_HAS_CUSTOM_SWAP_TO_MAIN
ARG_UNUSED(dummy_thread);
#else
/*
* Initialize the current execution thread to permit a level of
* debugging output if an exception should happen during kernel
* initialization. However, don't waste effort initializing the
* fields of the dummy thread beyond those needed to identify it as a
* dummy thread.
*/
_current = dummy_thread;
dummy_thread->base.user_options = K_ESSENTIAL;
dummy_thread->base.thread_state = _THREAD_DUMMY;
#endif
/* _kernel.ready_q is all zeroes */
/*
* The interrupt library needs to be initialized early since a series
* of handlers are installed into the interrupt table to catch
* spurious interrupts. This must be performed before other kernel
* subsystems install bonafide handlers, or before hardware device
* drivers are initialized.
*/
_IntLibInit();
/* ready the init/main and idle threads */
for (int ii = 0; ii < K_NUM_PRIORITIES; ii++) {
sys_dlist_init(&_ready_q.q[ii]);
}
/*
* prime the cache with the main thread since:
*
* - the cache can never be NULL
* - the main thread will be the one to run first
* - no other thread is initialized yet and thus their priority fields
* contain garbage, which would prevent the cache loading algorithm
* to work as intended
*/
_ready_q.cache = _main_thread;
_new_thread(_main_thread, _main_stack,
MAIN_STACK_SIZE, _main, NULL, NULL, NULL,
CONFIG_MAIN_THREAD_PRIORITY, K_ESSENTIAL);
_mark_thread_as_started(_main_thread);
_add_thread_to_ready_q(_main_thread);
#ifdef CONFIG_MULTITHREADING
_new_thread(_idle_thread, _idle_stack,
IDLE_STACK_SIZE, idle, NULL, NULL, NULL,
K_LOWEST_THREAD_PRIO, K_ESSENTIAL);
_mark_thread_as_started(_idle_thread);
_add_thread_to_ready_q(_idle_thread);
#endif
initialize_timeouts();
/* perform any architecture-specific initialization */
kernel_arch_init();
}
