Where can i find update_kernel in U-Boot source code


I want to modify u boot and the update scenario. Where can i find update_kernel update_uboot etc code
I found this article

thank you


You cannot. These are not part of the U-Boot sources.

They are set from the U-Boot script you load with run setupdate.
The script is part of the OE meta-data. flash_blk.scr for updating from an SD card, flash_eth.scr for updating from a TFTP server.


Note that the script needs to be packaged into an U-Boot image.