initcpu.c

一个小的嵌入式os

/*
*********************************************************************************************************
* File Name:InitCPU.C
* Description: 初始化 CPU WRAPPER 各寄存器.
* Author: kaka  ([e-mail]).
*********************************************************************************************************
*/
#include "44b0x.h"
#define  Global_Def


#define  dDA        0           // Enable data abort.
#define  dRSE       0           // read stall disable.
#define  dWE        0           // Disable write buffer operation.

#define  dCM       3           // Full Cache enable (8KB cache).
#define  dSE        0           // stall disable.

#define  dFIX        1          // fixed priorities
#define  dLCD_DMA    0          // Determines the LCD_DMA bus priority
#define  dZDMA       1          // Determines the ZDMA bus priority
#define  dBDMA       2          // Determines the BDMA bus priority
#define  dnBREQ      3          // Determines the nBREQ bus priority
#define  dSBUSCON    0x80001b1b //((dFIX<<31)+(dLCD_DMA<<6)+(dZDMA<<4)+(dBDMA<<2)+dnBREQ)

void InitCPU (void)
{
    SYSCFG  = ((dDA<<5) + (dRSE<<4) + (dWE<<3) + (dCM<<1) + dSE);
  NCACHBE0 =0xc0002000; //0xc0002000;      //it's important for the I/O Port
   //NCACHBE1 = 0xc0002000;				//这里表示不使用
   										//cache的地址范围，
   										//对于I/O口不应该设置
   										//cache
    SBUSCON = dSBUSCON;
}

/*
*********************************************************************************************************
*       END
*********************************************************************************************************
*/