SD卡无法挂载(论坛的相似问题贴都已经尝试，无效)

msh />list_device
                 type         ref count
-------- -------------------- ----------
pipe0    Pipe                 2
sd0      Block Device         0
fs       Block Device         1
norflash Block Device         0
spi_flas SPI Device           0
rtc      RTC                  0
e0       Network Interface    1
adc3     ADC Device           0
adc2     ADC Device           0
wdt      WDT Device           0
uart8    Character Device     1
uart6    Character Device     0
uart5    Character Device     0
uart4    Character Device     1
uart2    Character Device     1
uart1    Character Device     2
spi4     SPI Bus              0
spi2     SPI Bus              0
spi1     SPI Bus              0
i2c1     I2C Bus              0
pin      Pin Device           0
msh />

ROM file system initializated!
[I/FAL] The FAL block device (fs) created successfully
norflash0 filesystem block size: 4096, total blocks: 2809, free blocks: 2807.
[971] I/SDIO: SD card capacity 995328 KB.
mount sd filesystem fail.
[FlashDB][kv][env] (../packages/FlashDB-v1.0.0/src/fdb_kvdb.c:1885) KVDB size is 1048576 bytes.
[FlashDB] FlashDB V1.1.2 is initialize success.

msh />mkfs -t elm sd0
msh />mount sd0 /sdcard elm
mount device sd0(elm) onto /sdcard ... failed!
msh />

int mnt_init(void)
{
    int fd, size;
    struct statfs elm_stat;
    struct fal_blk_device* blk_dev;
    //根目录下挂载romfs
    if (dfs_mount(RT_NULL, "/", "rom", 0, &(romfs_root)) == 0)
    {
         rt_kprintf("ROM file system initializated!\n");
    }
    else
    {
         rt_kprintf("ROM file system initializate failed!\n");
    }
    /* fal init */
    fal_init();
    /* create block device */
    blk_dev = (struct fal_blk_device*)fal_blk_device_create("fs");
    if (blk_dev == RT_NULL)
    {
        // rt_kprintf("Can't create a block device on '%s' partition.\n", "fs");
    }
    /* mount elmfat file system to FS_PARTITION_NAME */
    if (dfs_mount("fs", "/norflash0", "elm", 0, 0) != 0)
    {
        /* make a elmfat format filesystem */
        if (dfs_mkfs("elm", "fs") != 0)
        {
            // rt_kprintf("make elmfat filesystem fail.\n");
            return RT_ERROR;
        }
        dfs_mount("fs", "/norflash0", "elm", 0, 0);
    }
    /* Get elmfat file system statistics */
   if (statfs("/norflash0", &elm_stat) == 0)
    rt_kprintf("norflash0 filesystem block size: %d, total blocks: %d, free blocks: %d.\n",
                elm_stat.f_bsize, elm_stat.f_blocks, elm_stat.f_bfree);
    rt_thread_mdelay(1000);
    if (dfs_mount("sd0", "/sdcard", "elm", 0, 0) != 0)
    {
        /* make a elmfat format filesystem */
        if (dfs_mkfs("elm", "sd0") != 0)
        {
            rt_kprintf("make sd filesystem fail.\n");
            return RT_ERROR;
        }
        if(dfs_mount("sd0", "/sdcard", "elm", 0, 0) != 0)
        {
            rt_kprintf("mount sd filesystem fail.\n");
            return RT_ERROR;
        }
    }
    rt_kprintf("make sd filesystem success.\n");
    if (statfs("/sdcard", &elm_stat) == 0)
         rt_kprintf("sdcard filesystem block size: %d, total blocks: %d, free blocks: %d.\n",
                     elm_stat.f_bsize, elm_stat.f_blocks, elm_stat.f_bfree);
        return RT_EOK;
}