I know that the iMX6 rom loader when booting from a device (SD, MMC, NAND, etc...) loads an image vector table containing a DCD table used to configure other on chip pheripherals (typically the DDR memory controller).
My question is: from where does the image vector table + DCD is taken when the USB serial boot is selected by bootpins?
For example, the MFG Tool loads in DDR SDRAM the u-boot + kernel image + ramdisk using the USB serial interface, so the DDR controller should be intialized in some way.
I'm asking this because I need to change the DDR controller initialization due to differences between the rams used in our custom board and ram used in SabreSD reference board.
Thank you in advance, any explanation will be appreciated.