u-boot/lib/efi_loader/capsule_esl.dtsi.in

// SPDX-License-Identifier: GPL-2.0+
/**
 * Devicetree file with the public key EFI Signature List(ESL)
 * node. This file is used to generate the dtsi file to be
 * included into the DTB.
*/
/ {
	signature {
		capsule-key = /incbin/("ESL_BIN_FILE");
	};
};