xen: apply layer settings when xen DISTRO_FEATURE is enabled

These settings are necessary for Xen and enabling them here, using the
same mechanism that is used by k8s in this layer, simplifies building
images for Xen.

- Ensure that Xen mode is enabled in QEMU.
- On ARM platforms: enable Flattened Device Tree (FDT) support.

Signed-off-by: Christopher Clark <christopher.w.clark@gmail.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>

3 files changed, 15 insertions, 1 deletions

diff --git a/classes/meta-virt-xen-cfg.bbclass b/classes/meta-virt-xen-cfg.bbclass
new file mode 100644
index 00000000..61b32aa3
--- /dev/null
+++ b/classes/meta-virt-xen-cfg.bbclass
@@ -0,0 +1,6 @@
+# We need to load the Xen meta-virt config components, only if "xen"
+# is in the distro features.  Since we don't know the distro flags during
+# layer.conf load time, we delay using a special bbclass that simply includes
+# the META_VIRT_XEN_CONFIG_PATH file.
+
+include ${@bb.utils.contains('DISTRO_FEATURES', 'xen', '${META_VIRT_XEN_CONFIG_PATH}', '', d)}
diff --git a/conf/distro/include/meta-virt-xen.inc b/conf/distro/include/meta-virt-xen.inc
new file mode 100644
index 00000000..a92b08b4
--- /dev/null
+++ b/conf/distro/include/meta-virt-xen.inc
@@ -0,0 +1,6 @@
+# Make sure Xen mode is enabled in qemu
+PACKAGECONFIG_append_pn-qemu = " xen"
+
+# For builds for ARM platforms, enable fdt
+PACKAGECONFIG_append_pn-qemu_arm = " fdt"
+PACKAGECONFIG_append_pn-qemu_aarch64 = " fdt"
diff --git a/conf/layer.conf b/conf/layer.conf
index 697fb622..142621c3 100644
--- a/conf/layer.conf
+++ b/conf/layer.conf
@@ -43,8 +43,10 @@ INHERIT += "sanity-meta-virt"
 # We need to load the meta-virt config components, only if "virtualization"
 # is in the distro features.  Since we don't know the distro flags during
 # layer.conf load time, we delay using a special bbclass that simply includes
-# the META_VIRT_CONFIG_PATH file, and likewise for the k8s configs
+# the META_VIRT_CONFIG_PATH file, and likewise for the Xen and k8s configs
 META_VIRT_CONFIG_PATH = "${LAYERDIR}/conf/distro/include/meta-virt-default-versions.inc"
+META_VIRT_XEN_CONFIG_PATH = "${LAYERDIR}/conf/distro/include/meta-virt-xen.inc"
 K8S_CONFIG_PATH = "${LAYERDIR}/conf/distro/include/k8s-versions.inc"
 USER_CLASSES_append = " meta-virt-cfg"
 USER_CLASSES_append = " meta-virt-k8s-cfg"
+USER_CLASSES_append = " meta-virt-xen-cfg"