From bcf9147144f3499976a623f92712ecd0aca71912 Mon Sep 17 00:00:00 2001
From: Colin Percival <cperciva@FreeBSD.org>
Date: Wed, 7 Jun 2023 15:17:12 -0700
Subject: [PATCH] EC2: Default to "uefi-preferred" boot mode

In EC2, UEFI boots faster than BIOS, but not all amd64 instance types
support UEFI.  AMIs need to have their boot mode designated, which
created a dilemma: Faster boots, or wider compatibility?

The recently added "uefi-preferred" option solves this: AMIs can be
marked to use UEFI where it's available, but fall back to BIOS on
instance types which do not support UEFI.

This uses bsdec2-image-upload 1.4.6, which recently landed in the
ports tree.

PR:		265697
Reviewed by:	delphij, imp
MFC after:	1 week
Sponsored by:	https://www.patreon.com/cperciva
Differential Revision:	https://reviews.freebsd.org/D40470
---
 release/Makefile.ec2 | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/release/Makefile.ec2 b/release/Makefile.ec2
index b29f54715fb..e26f4f705cc 100644
--- a/release/Makefile.ec2
+++ b/release/Makefile.ec2
@@ -25,11 +25,14 @@ SSMOPTS=	--ssm-name ${SSMPREFIX}/${TARGET_ARCH:S/aarch64/arm64/}/base/ufs/${REVI
 EC2ARCH=	--${TARGET_ARCH:S/aarch64/arm64/}
 .endif
 .if !defined(AMIBOOTMETHOD)
-AMIBOOTMETHOD=	UEFI
+AMIBOOTMETHOD=	UEFI-PREFERRED
 .endif
 .if ${AMIBOOTMETHOD} == "UEFI" && ${TARGET_ARCH} == "amd64"
 BOOTMODEOPT=	--uefi
 .endif
+.if ${AMIBOOTMETHOD} == "UEFI-PREFERRED" && ${TARGET_ARCH} == "amd64"
+BOOTMODEOPT=	--uefi-preferred
+.endif
 
 CLEANFILES+=		ec2ami