eMMC device on 6ULL

  • When I compile with all the emmc support I can find, I can see
    the mmc device in Uboot:

    efusA7UL # mmc info
    Device: FSL_SDHC
    Manufacturer ID: 13
    OEM: 14e
    Name: Q2J54
    Tran Speed: 52000000
    Rd Block Len: 512
    MMC version 4.0
    High Capacity: Yes
    Capacity: 3.6 GiB
    Bus Width: 4-bit

    efusA7UL # mmc part
    ## Unknown partition table

    No partitions defined though.
    After booting to Linux, I don't get a /dev/mmcblk0 device node, nor any mention of a /dev/mmc* device at all.

    Any clues to what steps I may be missing?

  • Hi,

    yes that is correct you see the stats of the emmc. You can´t
    see the partition table because there is no partition table installed
    yet. Normally you can boot linux and call the tool fdisk:
    fdisk /dev/mmcblkX

    • o -> create empty DOS partition table
    • n -> add new partition
    • w -> write table to disk and exit

    After that you can create a filesystem on you partition
    mke2fs –t ext4 /dev/mmcblkXpY

    Now the partition table and the filesystem is available und you can access emmc from UBoot.

    Why you don´t see the emmc in the /dev directory is another question. Do you have enabled the define
    in the device tree?

    Your F&S Support Team

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
    Da dies ein internationales Forum ist, bitten wir darum, Beiträge möglichst in Englisch zu verfassen.

    Edited once, last by fs-support_PJ ().