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/*
 * This file is part of the libpayload project.
 *
 * Copyright (C) 2008 Advanced Micro Devices, Inc.
 *
 * 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. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 */

#include <arch/types.h>

/* This structure seeds the stack.  We provide
   the return address of our main function, and
   further down, the address of the function 
   that we call when we leave and try to restore
   the original stack.  At the very bottom of the
   stack we store the orignal stack pointer
   from the calling application
*/

static void start_main(void);
extern void _leave(void);

static struct {
	uint32_t eip[2];
	uint32_t raddr[2];
	uint32_t esp;
} initial_stack __attribute__((section (".istack"))) = {
	{ (uint32_t) start_main, 0 },
	{ (uint32_t) _leave, 0 },
	(uint32_t) &initial_stack,
};

void * _istack = &initial_stack;

/* This is our C entry function - set up the system
   and jump into the payload entry point */

static void start_main(void)
{
	extern int main(void);

	/* Set up the consoles */
	console_init();

	/* Gather system information */
	lib_get_sysinfo();

	/* Any other system init that has to happen before the
	   user gets control goes here. */

	/* Go to the entry point */

	/* in the future we may care about the return value */
	(void) main();

	/* Returning here will go to the _leave function to return
	   us to the original context */
}