linux环境下遍历PCI设备

2.outl()和inl()

<span style="font-weight: normal;"><span style="font-family:Microsoft YaHei;font-size:14px;">#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<sys/io.h>

#define MAX_BUS 256                         //bus bunber:0~255
#define MAX_DEV 32                          //device number:0~31
#define MAX_FUN 8                            //function number:0~7

#define BASE_ADDR 0x80000000 //基地址，enable=1
#define CONFIG_ADDR 0xcf8
#define CONFIG_DATA 0xcfc

typedef unsigned int WORD;   //4byte

int main()
{
    WORD bus,dev,fun;
    WORD addr,data;
    int ret=0;

    printf("bus#\tdev#\tfun#\t");
    printf("\n");

    ret=iopl(3);      //set high power
    if(ret<0)
    {
        perror("iopl set high power error");
        return -1;
    }
 
    for(bus=0;bus<MAX_BUS;++bus)
    {
        for(dev=0;dev<MAX_DEV;++dev)
        {
            for(fun=0;fun<MAX_FUN;++fun)
            {
                addr=BASE_ADDR|(bus<<16)|(dev<<11)|(fun<<8);               //把number们分别左移到相应的位上去，register number默认设为0
                outl(addr,CONFIG_ADDR);                                                       //put addr into CONFIG_ADDR
                data=inl(CONFIG_DATA);                                                        //read address from CONFIG_DATA
                if((data!=0xffffffff)&&(data!=0))                                             //如果vender ID和Device ID位全是1，代表没有该设备
                    printf("%2x\t%2x\t%2x\n",bus,dev,fun);                            //找到PCI设备后打印他的bus,dev,fun number
            }
        }
    }

    ret=iopl(0);         //set low power                       
    if(ret<0)
    {
        perror("iopl set low power error");
        return -1;
    }

    return 0;
}</span></span>