ZynqのPLを操作するLinuxドライバ (ユーザプログラム編)

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <errno.h>

int main()
{
    int uiofd;
    int err;
    int i;
    unsigned icount;
    unsigned int* map_addr;
    unsigned int cnt;
    unsigned int one = 1;

    uiofd = open("/dev/uio0", O_RDWR);
    if (uiofd < 0) {
        perror("uio open:");
        return errno;
    }

    map_addr = (unsigned int*)mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, uiofd, 0);
    if (!map_addr){
        fprintf(stderr, "mmap failed\n");
        return errno;
    }

    write(uiofd, &one, 4);    // enable interrupt to uio_pdrv_genirq
    map_addr[0] = 0x0BEBC200;    // 200M
    map_addr[1] = 0; // disable
    map_addr[2] = 1;    // clear interrupt
    map_addr[1] = 1; // enable

    for(i = 0;; ++i) {
        /* Print out a message, for debugging. */
        if (i == 0)
            fprintf(stderr, "Started uio test driver.\n");
        else
            fprintf(stderr, "Interrupts: %d,%x\n", icount, cnt);

        /* Wait for next interrupt. */
        err = read(uiofd, &icount, 4);
        if (err != 4) {
            perror("uio read:");
            break;
        }
        cnt = map_addr[3];
        map_addr[2] = 1;    // clear interrupt
        write(uiofd, &one, 4);    // enable interrupt again
    }
    munmap(map_addr, 4096);
    close(uiofd);
    return errno;
}