[U-Boot] [U-boot] CONFIG_OF_EMBED question

Hi, experts:

If i defined CONFIG_OF_EMBED, then:

Where could i find _binary_dt_dtb_start's definition?

In arch/arm/lib/board.c:

gd->fdt_blob = _binary_dt_dtb_start;

but i could not find _binary_dt_dtb_start's definition.

Best wishes,