Loading Images onto eMMC Devices
Contents
Background
Newer EMAC products have started using eMMC in place of NAND flash. eMMC is an embedded MMC compliant memory that takes the form of an integrated circuit instead of a media card.
U-Boot does not support writing to file systems in eMMC. To overcome this issue, the embedded target has to be boot into Linux using an auxiliary method. Once U-Boot has been loaded into RAM, it can be used to load the target kernel using TFTP and boot into a file system stored in NFS.
Once the board has boot into Linux the eMMC can be partitioned, formatted, and the root file system can be extracted. The SoM-3517M requires a special FAT formatted partition that contains the bootloader and Linux kernel image.
This article explains the general process of writing the eMMC from Linux as well as some specifics related to the programming the SoM-3517M.
The procedures below required that you have a TFTP and NFS server setup on a host computer. For instructions on setting up a TFTP server see the following page: Installing TFTP server
For installation of a bootable NFS see the following page: Setting up an NFS File Server
For instruction for booting into NFS with U-Boot: Booting with an NFS Root Filesystem
