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