README
1Field Fail-Save U-boot Update
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3Field Fail-Save u-boot update is a feature that allows save u-boot update
4of FOX and XMC products that are rolled out in the field.
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6The feature is initially implemented for designs based on LS102x SoC, but in
7theory can be used on all designs that are booting from parallel NOR flash.
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9The implementation expects redundant (secondary) u-boot image on a predefined
10location in the NOR flash, u-boot execution will be transferred to the redundant
11(secondary) u-boot and redundant u-boot will be started if 'updateduboot' envvar
12is set to 'yes'.
13Update logic check_for_uboot_update() has to be invoked from the design early
14before relocation just after SoC initialization, e.g from board_early_init_f or
15misc_init_f functions.
16By design it is expected that primary u-boot image is burned in the factory and
17never updated, and in case u-boot update is required it can flashed and started
18from secondary u-boot location.
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