arm-bsp/uefi_capsule: Add UEFI capsule generation class

This class currently supports only a single firmware binary. The
required capsule parameters needs to be set, if not the build fails.

Signed-off-by: Gowtham Suresh Kumar <gowtham.sureshkumar@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>

meta-arm/classes/uefi_capsule.bbclass

@@ -0,0 +1,46 @@
+# This class generates UEFI capsules
+# The current class supports generating a capsule with single firmware binary
+
+inherit python3native
+
+IMAGE_TYPES += "uefi_capsule"
+
+# edk2 base tools should be installed in the native sysroot directory
+do_image_uefi_capsule[depends] += "edk2-basetools-native:do_populate_sysroot"
+
+# By default the wic image is used to create a capsule
+CAPSULE_IMGTYPE ?= "wic"
+
+# IMGDEPLOYDIR is used as the default location of firmware binary for which the capsule needs to be created
+CAPSULE_IMGLOCATION ?= "${IMGDEPLOYDIR}"
+
+# The generated capsule by default has uefi.capsule extension
+CAPSULE_EXTENSION ?= "uefi.capsule"
+
+# The following variables must be set to be able to generate a capsule update
+UEFI_FIRMWARE_BINARY ?= ""
+UEFI_FIRMWARE_VERSION ?= ""
+UEFI_FIRMWARE_LSV ?= ""
+UEFI_FIRMWARE_GUID ?= ""
+UEFI_FIRMWARE_UPDATE_INDEX ?= ""
+
+# Check if the required variables are set
+python() {
+    for var in ["UEFI_FIRMWARE_BINARY", "UEFI_FIRMWARE_VERSION", "UEFI_FIRMWARE_LSV", "UEFI_FIRMWARE_GUID", "UEFI_FIRMWARE_UPDATE_INDEX"]:
+        if not d.getVar(var):
+            raise bb.parse.SkipRecipe(f"{var} not set")
+}
+
+IMAGE_CMD:uefi_capsule(){
+
+    # Force the GenerateCapsule script to use python3
+    export PYTHON_COMMAND=${PYTHON}
+
+    ${STAGING_DIR_NATIVE}/usr/bin/edk2-BaseTools/BinWrappers/PosixLike/GenerateCapsule -e -o \
+    ${CAPSULE_IMGLOCATION}/${UEFI_FIRMWARE_BINARY}.${CAPSULE_EXTENSION} --fw-version ${UEFI_FIRMWARE_VERSION} \
+    --lsv ${UEFI_FIRMWARE_LSV} --guid ${UEFI_FIRMWARE_GUID} --verbose --update-image-index \
+    ${UEFI_FIRMWARE_UPDATE_INDEX} --verbose ${CAPSULE_IMGLOCATION}/${UEFI_FIRMWARE_BINARY}
+}
+
+# The firmware binary should be created before generating the capsule
+IMAGE_TYPEDEP:uefi_capsule:append = "${CAPSULE_IMGTYPE}"