arm linux读寄存器

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/io.h>

int main() {
    unsigned int reg_value;

    // 打开/dev/mem设备文件
    int mem_fd = open("/dev/mem", O_RDWR | O_SYNC);
    if (mem_fd < 0) {
        perror("Failed to open /dev/mem");
        return -1;
    }

    // 映射寄存器地址到用户空间
    void *reg_addr = mmap(NULL, sizeof(unsigned int), PROT_READ | PROT_WRITE, MAP_SHARED, mem_fd, 0x10000000); // 假设寄存器地址为0x10000000
    if (reg_addr == MAP_FAILED) {
        perror("mmap failed");
        close(mem_fd);
        return -1;
    }

    // 读取寄存器值
    reg_value = *(unsigned int *)reg_addr;
    printf("Register value: 0x%x\n", reg_value);

    // 解除映射并关闭文件
    munmap(reg_addr, sizeof(unsigned int));
    close(mem_fd);

    return 0;
}