initramfs-image-minimal.bb: add recipe

Add a recipe for a minimal initramfs image.

Note that the purpose of this recipe is totally different from that
of core-image-minimal-initramfs.bb. The latter is supposed to be used
in the live image to "boot" or "install". The former is more like a
traditional initramfs whose responsibility is to deal with the kernel
parameters and then bring up the real root file system.

After adding this recipe, we could specify INITRAMFS_IMAGE to be
"initramfs-image-minimal". Note that in OE, we didn't have a reference
image recipe for INITRAMFS_IMAGE.

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>

diff --git a/meta/recipes-core/images/initramfs-image-minimal.bb b/meta/recipes-core/images/initramfs-image-minimal.bb
new file mode 100644 (file)
index 0000000..24501e0
--- /dev/null
+++ b/meta/recipes-core/images/initramfs-image-minimal.bb
@@ -0,0 +1,19 @@
+# Minimal initramfs image
+DESCRIPTION = "Minimal initramfs image used to bring up the system."
+LICENSE = "MIT"
+
+PACKAGE_INSTALL = "initramfs-framework-base initramfs-module-udev busybox udev base-passwd"
+
+# Do not pollute the initramfs image with rootfs features
+IMAGE_FEATURES = ""
+IMAGE_LINGUAS = ""
+
+IMAGE_FSTYPES = "${INITRAMFS_FSTYPES}"
+inherit image
+
+BAD_RECOMMENDATIONS += "busybox-syslog"
+
+# We need to set USE_DEVFS to "0" here to trigger creation of device nodes at rootfs time.
+# The reason here is that, when this initramfs is bundled into kernel, we need /dev/console
+# to be there before init is run.
+USE_DEVFS = "0"