mpc55xx_init.c

mpc55**系列芯片的例程 包括SCI,SPI,TIMER,FIT,EDMA等几乎所有功能的实现

/*
 *
 * FILE : MPC55xx_init.c
 *
 * DESCRIPTION:
 *  This file contains the MPC55xx derivative needed initializations. 
 *  usr_init() is called by the startup code of the application at initialization time
 *  You can add needed hardware initializations here.
 *  This file also contains the RCHW and Reset Vector setup:
/*  The chip is by default setup to boot from internal Flash and the watchdog is disabled.
 */
/* Sep 17 2007 SM - removed branch to exception and INTC interrupts, renamed boot section */

/* #include "Exceptions.h"*/    /* IVPR and default exception handlers setup */
/* #include "INTCInterrupts.h"*/ /* INTC Interrupts Requests configuration */
#include "MPC5633m_HWInit.h"

#pragma section code_type ".init"

#define INIT_DERIVATIVE_INTERNAL_SETUP 1
#define INIT_EXTERNAL_BUS_INTERFACE_SETUP 1

#ifndef INIT_DERIVATIVE_INTERNAL_SETUP
#pragma error INIT_DERIVATIVE_INTERNAL_SETUP should be defined !
#endif

#ifndef INIT_EXTERNAL_BUS_INTERFACE_SETUP
#pragma error INIT_EXTERNAL_BUS_INTERFACE_SETUP should be defined !
#endif

#ifdef __cplusplus
extern "C" {
#endif

extern __asm void __start();
__asm void usr_init();
/*lint -esym(752,__start) */

#ifdef __cplusplus
}
#endif

/*****************************************************************/
/* usr_init():                                                   */
/*   Define here the needed hardware initializations at startup  */

__asm void usr_init()
{
    /* Add needed hardware initializations in this function */
    nofralloc

    mflr     r30                         /* Save off return address in NV reg */

#if INIT_DERIVATIVE_INTERNAL_SETUP==1
    bl      INIT_Derivative              /* Derivative specific hardware initializations */
#endif
#if INIT_EXTERNAL_BUS_INTERFACE_SETUP==1
    bl      INIT_ExternalBusAndMemory    /* Set up access to external memory (inc. chip select and MMU) */
#endif
/*    bl      EXCEP_InitExceptionHandlers*/   /* Set up Default Exception handling */
/*    bl      INTC_InitINTCInterrupts*/       /* Set up INTC Interrupts Requests handling */

    mtlr    r30                          /* Get saved return address */

    blr
}

#ifdef __cplusplus
extern "C" {
#endif

/**************************************************************/
/* RCHW and Reset Vector setup:                               */
/*   The chip is by default setup to boot from internal Flash */
/*   and the watchdog is disabled.                            */ 

typedef void (*resetfuncptr)(void);

#pragma push /* Save the current state */
/*#pragma section sconst_type ".__bam_bootarea"*/
#pragma section sconst_type ".boot"

extern const unsigned long bam_rchw;
extern const resetfuncptr bam_resetvector;

/* RCHW_VALUE Flags */
#define RCHW_WTE 0x0400L        /* Enable Watchdog */
#define RCHW_VLE 0x0100L        /* Enable Variable Length Encoding*/
#define RCHW_PS0_32BITS 0x0000L /* Boot from External Bus CS0, 32-bit CS0 port size. */
#define RCHW_PS0_16BITS 0x0200L /* Boot from External Bus CS0, 16-bit CS0 port size. */
#define RCHW_BOOTIDENTIFIER 0x005AL

/* Used RCHW value: boot from internal flash, watchdog disabled */
#if VLE_IS_ON == 1
#define RCHW_VALUE RCHW_BOOTIDENTIFIER|RCHW_PS0_32BITS|RCHW_VLE
#else
#define RCHW_VALUE RCHW_BOOTIDENTIFIER|RCHW_PS0_32BITS 
#endif

const unsigned long bam_rchw = (RCHW_VALUE)<<16;
const resetfuncptr bam_resetvector = __start;

#pragma pop

#ifdef __cplusplus
}
#endif