BeagleBone uboot: BeagleBone Green Gateway not defined in uboot?

I have tried to boot a Beaglebone Green Gateway via the current GenericSD.img.xz at https://download.freebsd.org/ftp/releases/arm/armv7/ISO-IMAGES/13.0/FreeBSD-13.0-RELEASE-arm-armv7-GENERICSD.img.xz

The board booted, but it did not have anything functional in the sense of wland or ethernet.

So I installed (after putting the SD-card in a BeagleBone Green, which was able to find an ethernet port and a working internet connection) the beaglebone uboot:
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pkg install sysutils/u-boot-beaglebone
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That resulted in the message that there was no device tree:
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Loading Environment from EXT4...
** Unable to use mmc 0:1 for loading the env **
Board: BeagleBone Black
<ethaddr> not set. Validating first E-fuse MAC
BeagleBone Black:
Model: SeeedStudio BeagleBone Green Gateway:
BeagleBone: cape eeprom: i2c_probe: 0x54:
BeagleBone: cape eeprom: i2c_probe: 0x55:
BeagleBone: cape eeprom: i2c_probe: 0x56:
BeagleBone: cape eeprom: i2c_probe: 0x57:
Net:   eth0: MII MODE
cpsw, usb_ether
Press SPACE to abort autoboot in 0 seconds
board_name=[A335BNLT] ...
board_rev=[GG1A] ...
switch to partitions #0, OK
mmc0 is current device
SD/MMC found on device 0
switch to partitions #0, OK
mmc0 is current device
Scanning mmc 0:1...
Found EFI removable media binary efi/boot/bootarm.efi
libfdt fdt_check_header(): FDT_ERR_BADMAGIC

<snip>
No valid device tree blob found!
WARNING! Trying to fire up the kernel, but no device tree blob found!
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How can I add a  device tree blob for the BeagleBone Green Gateway?



Kind Regards,
Johan Henselmans

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