/****************************************************************************
 * include/nuttx/init.h
 *
 *   Copyright (C) 2007, 2008, 2011, 2016 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name NuttX 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 THE
 * COPYRIGHT OWNER OR 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.
 *
 ****************************************************************************/

#ifndef __INCLUDE_NUTTX_INIT_H
#define __INCLUDE_NUTTX_INIT_H

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>
#include <nuttx/compiler.h>

#include <stdint.h>

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/
/* Macros for testing which OS services are available at this phase of
 * initialization.
 */

#define OSINIT_MM_READY()        (g_os_initstate >= OSINIT_MEMORY)
#define OSINIT_HW_READY()        (g_os_initstate >= OSINIT_HARDWARE)
#define OSINIT_OS_READY()        (g_os_initstate >= OSINIT_OSREADY)
#define OSINIT_OS_INITIALIZING() (g_os_initstate  < OSINIT_OSREADY)

/****************************************************************************
 * Public Types
 ****************************************************************************/

/* Initialization state.  OS bring-up occurs in several phases: */

enum os_initstate_e
{
  OSINIT_POWERUP  = 0,  /* Power-up.  No initialization yet performed.
                         * Depends on .bss initialization logic for this
                         * value. */
  OSINIT_BOOT     = 1,  /* Basic boot up initialization is complete.  OS
                         * services and hardware resources are not yet
                         * available. */
  OSINIT_MEMORY   = 2,  /* The memory manager has been initialized */
  OSINIT_HARDWARE = 3,  /* MCU-specific hardware is initialized.  Hardware
                         * resources such as timers and device drivers are
                         * now avaiable.  Low-level OS services sufficient
                         * to support the hardware are also available but
                         * the OS has not yet completed its full
                         * initialization. */
  OSINIT_OSREADY  = 4   /* The OS is fully initialized and multi-tasking is
                         * active. */
};

/****************************************************************************
 * Public Data
 ****************************************************************************/

#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif

/* This is the current initialization state.  The level of initialization
 * is only important early in the start-up sequence when certain OS or
 * hardware resources may not yet be available to the OS-internal logic.
 */

EXTERN uint8_t g_os_initstate;  /* See enum os_initstate_e */

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/

/* This entry point must be supplied by the application */

int CONFIG_USER_ENTRYPOINT(int argc, char *argv[]);

/* Functions contained in os_task.c *****************************************/
/* OS entry point called by boot logic */

void os_start(void) noreturn_function;

#undef EXTERN
#ifdef __cplusplus
}
#endif

#endif /* __INCLUDE_NUTTX_INIT_H */
