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Stand-Alone eMMC Boot
By default, the U-boot Boot environment is configured to auto-detect if there is a device connected to interface mmc0, which corresponds to the SD card slot. If not, then it will boot from mmc1, which is eMMCautodetect which mmc interface U-boot was booted from (See i.MX7: Boot Configurations) and boot the kernel and root file system from the same device. However, if you would like to boot Linux from eMMC regardless of whether or not there is an SD card insertedthe boot source for U-Boot, then disable auto-detection and set the mmc boot device to mmc1 by modifying the environment as follows:
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