ATF load_serialno internal API


#1

Hi,

In the past on Hikey there was this load_serialno internal API which could be used to retrieve board serial number

Usually this was set through some OEM fastboot command.

Now moving to Hikey960 it seems this API does not exist in ARM ATF.
There exists a board id read but no such serial number read function.

On Hikey there is a prototype but no implementation for the same.

I assume with flash storage moving to UFS, there may be changes related to partitions layout and possibly location for the serial number.

Is adding the serial number a matter of 96boards BSP work ?
Would this happen in 96boards github fork project?

Thanks & Regards.


#2

load_serialno() is only ever called on a hikey by a special piece of code in BL1 that is reachable only when we don’t boot from eMMC (i.e. during the debrick proceedure).

To be honest there’s a strong argument that code like this doesn’t belong in ARM trusted firmware in the first place (fastboot could probably be implemented by the BL31 payload even when booting from USB). As such you should not assume that there is any plan to implement something similar for hikey960; even if it were implemented as a temporary convenience in the long term this type of code should be removed (otherwise we become misaligned with upstream ARM TF).