Hello David,

Not sure if your question has anything to do with YOCTO (in contrary,
I this is has nothing to do with it). I see kerne's .dtb from U-BOOT
messages while booting the system:

debug: [enable_uboot_overlays=1] ...
debug: [enable_uboot_cape_universal=1] ...
debug: [uboot_base_dtb_univ=am335x-boneblack-uboot-univ.dtb] ...
uboot_overlays: [uboot_base_dtb=am335x-boneblack-uboot-univ.dtb] ...
<<======= .dtb used
uboot_overlays: Switching too: dtb=am335x-boneblack-uboot-univ.dtb ...
loading /boot/dtbs/5.7.4-bone10/am335x-boneblack-uboot-univ.dtb ...
<<======= .dtb loaded
210649 bytes read in 183 ms (1.1 MiB/s)
uboot_overlays: [fdt_buffer=0x60000] ...
uboot_overlays: loading /lib/firmware/BB-SPI0-SC16IS740-00A0.dtbo ...
2291 bytes read in 698 ms (2.9 KiB/s)

You can also stop in U-BOOT monitor and issue: printenv, then search
for dtb variables.

In my case it gives me the following:
...
uboot_base_dtb=am335x-boneblack-uboot.dtb <<======= This one is
probably one which U-BOOT uses for its purposes
uboot_base_dtb_univ=am335x-boneblack-uboot-univ.dtb <<======= One used
by the kernel
...

Hope this helps.

Best Regards,
Zoran
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