board_init.c.svn-base

我们自己开发的一个OSEK操作系统！不知道可不可以？

#include "board.h"
#include "OS_CPU.h"
#include "board_mpc555.h"

/************************************************************************
 *
 * This is the first part of the initialization sequence that is
 * implemented in C, but still running from ROM.
 *
 * The main purpose is to initialize the RAM so that we can 
 * relocate the code to RAM.
 *
 * Be aware of the restrictions: global data is read-only, BSS is not
 * initialized, and stack space is limited to a few kB.
 *
 ************************************************************************
 */
extern void relocate_code(int, int);

void board_init_f()
{
	ULONG sp_addr;		/*stack pointer*/
	ULONG des_addr;			/*destination address of relocatable code*/
	ULONG s;

	des_addr = CFG_SDRAM_BASE;
	sp_addr = CFG_SDRAM_BASE + CFG_SDRAM_SIZE;		/*stack is in the high address of RAM*/

	sp_addr -= sizeof(bd_t);		/*some space reserved for board information*/
	sp_addr &= ~(4096 - 1);		/*4kB reserved for other use*/
	
	/*
	 * Finally, we set up a new (bigger) stack.
	 *
	 * Leave some safety gap for SP, force alignment on 16 byte boundary
	 * Clear initial stack frame
	 */
	sp_addr -= 16;		
	sp_addr &= ~0xF;		
/*	s = (ULONG *)sp_addr;
	*(s--) = 0;
	*(s--) = 0;
	sp_addr = (ULONG)s;*/

	relocate_code(sp_addr, des_addr);		/*it will not return from relocate_code*/
}

void board_init_r()
{
}