I am reading the GRUB manual at https://www.gnu.org/software/grub/manual/grub/grub.html On the front page it states:
Broken links and other corrections or suggestions can be sent to <bug-grub@gnu.org><mailto:bug-grub@gnu.org> so I am writing to you. (In the IBM world, documents came with an RCF on the last page: Reader Comment Form, for comments, corrections, or suggestions). 16.3 The list of command-line and menu entry commands 16.3.21 linux Command: devicetree file Load a device tree blob (.dtb) from a filesystem, for later use by a Linux kernel. Does not perform merging with any device tree supplied by firmware, but rather replaces it completely. GNU/Linux<https://www.gnu.org/software/grub/manual/grub/grub.html#GNU_002fLinux>. As you can see, the heading for the devicetree command says "linux". Thank you, Shimon