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The MLO.byteswap and u-boot.img is pre-installed in SPI NOR flash at factory default. SMARC-T4378 is designed to always boot upi up from SPI NOR flash and to load zImage, device tree blob and root file systems based on the setting of BOOT_SEL. If users need to fuse their own u-boot or perform u-boot upgrade. This section will instruct you how to do that.
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