imx6 secure boot - upgrade u-boot

[rsm4]

Hi,

We have a secure boot on imx6. The u-boot is located at QSPI flash. How is it possible to upgrade/update the u-boot. It must be mentioned that it shall be updated before a SW other than u-boot is executed. Also SPL is NOT used. Is there still a way to tell BOOT_ROM to boot from a different media (e.g.: eMMC) other than QSPI? Also no possibility given to modify the boot mode!

Following fuses are used:
BT_DIR_DIS = "1" --> Necessary for secure boot according RM
BT_FUSE_SEL = "1" --> Use Fuses instead GPIO
SEC_CONFIG [1:0] = "0x10" --> Closed
BOOT_CFG1[7:0] = "0x10" --> QSPI Boot

It would be fine to get an answer on this!

Best regards

rsm4

[IvanRuiz]

Hello,

You may find it helpful to refer to the following document for secure boot: https://www.nxp.com/webapp/Download?colCode=AN4581

or: https://www.nxp.com/docs/en/application-note/AN12056.pdf

BR,

Ivan.

[rsm4]

Hi, 

Thank you for your reply.

But my question is still open and not answered.

Best regards
rsm4