| Aleksandar Gerasimovski | efe1929 | 2021-12-10 11:07:53 +0100 | [diff] [blame] | 1 | Field Fail-Save U-boot Update |
| 2 | ----------------------------- |
| 3 | Field Fail-Save u-boot update is a feature that allows save u-boot update |
| 4 | of FOX and XMC products that are rolled out in the field. |
| 5 | |
| 6 | The feature is initially implemented for designs based on LS102x SoC, but in |
| 7 | theory can be used on all designs that are booting from parallel NOR flash. |
| 8 | |
| 9 | The implementation expects redundant (secondary) u-boot image on a predefined |
| 10 | location 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 |
| 12 | is set to 'yes'. |
| 13 | Update logic check_for_uboot_update() has to be invoked from the design early |
| 14 | before relocation just after SoC initialization, e.g from board_early_init_f or |
| 15 | misc_init_f functions. |
| 16 | By design it is expected that primary u-boot image is burned in the factory and |
| 17 | never updated, and in case u-boot update is required it can flashed and started |
| 18 | from secondary u-boot location. |