mantle/aws: add configuration support for boot mode

Add configuration for boot mode when used with a supported architecture
i.e. 'amd64/x86_64'. With a default of 'uefi-preferred'.

Author: prestist

mantle/platform/api/aws/images.go

@@ -344,11 +344,14 @@ func (a *API) CreateHVMImage(snapshotID string, diskSizeGiB uint, name string, d
 	if !set {
 		imdsSupport = ""
 	}
+	bootmode, set = os.LookupEnv("aws_boot_mode")
 
 	switch architecture {
 	case "amd64", "x86_64":
 		awsArch = ec2.ArchitectureTypeX8664
-		bootmode = "uefi-preferred"
+		if !set {
+			bootmode = "uefi-preferred"
+		}
 	case "arm64", "aarch64":
 		awsArch = ec2.ArchitectureTypeArm64
 		bootmode = "uefi"

src/cosalib/aws.py

@@ -119,6 +119,7 @@ def aws_run_ore(build, args):
     )
     os.environ["aws_imds_support"] = image_yaml['aws-imds-support']
     os.environ["aws_volume_type"]= image_yaml['aws-volume-type']
+    os.environ["aws_boot_mode"]= image_yaml['aws-boot-mode']
 
     # First add the ore command to run before any options
     ore_args = ['ore', 'aws', 'upload']

src/image-default.yaml

@@ -31,3 +31,4 @@ vmware-secure-boot: true
 # Defaults for AWS
 aws-imds-support: "v2.0"
 aws-volume-type: "gp3"
+aws-boot-mode: "uefi-preferred"