image_types_cboot: support UEFI signing

Signed-off-by: Matt Madison <matt@madison.systems>

classes/image_types_cboot.bbclass

@@ -1,9 +1,20 @@
 CBOOTIMG_KERNEL ?= "${DEPLOY_DIR_IMAGE}/${KERNEL_IMAGETYPE}"
 
+inherit tegra-uefi-signing
+
 oe_cbootimg() {
     bbfatal "This image type only supported on tegra platforms"
 }
 
+# Override this function in a bbappend to
+# implement other signing mechanisms
+sign_bootimg() {
+    if [ -n "${TEGRA_UEFI_DB_KEY}" -a -n "${TEGRA_UEFI_DB_CERT}" ]; then
+        tegra_uefi_attach_sign "$1"
+	rm "$1"
+	mv "$1.signed" "$1"
+    fi
+}
 oe_cbootimg_common() {
     outfile="$2"
     [ -n "$outfile" ] || outfile="${IMGDEPLOYDIR}/$1.cboot"
@@ -12,6 +23,7 @@ oe_cbootimg_common() {
         --ramdisk ${IMGDEPLOYDIR}/$1 \
         --cmdline "${KERNEL_ARGS}" \
         --output "$outfile"
+    sign_bootimg "$outfile"
     [ -n "$2" ] || ln -sf $1.cboot ${IMGDEPLOYDIR}/${IMAGE_LINK_NAME}.cboot
 }
 oe_cbootimg:tegra() {
@@ -27,5 +39,5 @@ make_cboot_image[vardepsexclude] += "DATETIME"
 CONVERSIONTYPES =+ "cboot"
 IMAGE_TYPES += "cpio.gz.cboot"
 
-CONVERSION_DEPENDS_cboot = "tegra-flashtools-native virtual/kernel:do_deploy"
+CONVERSION_DEPENDS_cboot = "tegra-flashtools-native virtual/kernel:do_deploy ${TEGRA_UEFI_SIGNING_TASKDEPS}"
 CONVERSION_CMD:cboot = "make_cboot_image ${type}"