[OE-core] [PATCH V1 3/3] kernel-initramfs: new recipe, creates initramfs bundled kernel packaging

[Ming Liu]

From: Ming Liu <peter.x.liu at external.atlascopco.com>

So far, there is not a workable way to package the initramfs bundled kernel
image, the only place is tmp/deploy from where we could get it, but if a
user want to add it into a certain image, there is no guarantee that he
will achieve it because a explicit dependency is missing between package
and bundle_initramfs, and this was designed to avoid introducing circular
dependencies when using kernel modules in the initramfs image.bb that is
caused by kernel.bbclass trying to build the initramfs before the kernel
packaging.

To fix this problem, the idea is to split the initramfs bundled kernel
packaging to a new recipe, make the do_install depend on kernel's deploy
task, then with the following config:

IMAGE_INSTALL_append = " kernel-initramfs"

The initramfs bundled kernel could be added to the image without
introducing any circular dependencies.

Signed-off-by: Ming Liu <peter.x.liu at external.atlascopco.com>
---
 meta/recipes-kernel/linux/kernel-initramfs.bb | 69 +++++++++++++++++++++++++++
 1 file changed, 69 insertions(+)
 create mode 100644 meta/recipes-kernel/linux/kernel-initramfs.bb

diff --git a/meta/recipes-kernel/linux/kernel-initramfs.bb b/meta/recipes-kernel/linux/kernel-initramfs.bb
new file mode 100644
index 0000000..7f9d72b
--- /dev/null
+++ b/meta/recipes-kernel/linux/kernel-initramfs.bb
@@ -0,0 +1,69 @@
+SUMMARY = "Initramfs bundled kernel image"
+DESCRIPTION = "When built, it packages a initramfs bundled kernel image of the \
+preferred virtual/kernel provider."
+
+SECTION = "kernel"
+
+LICENSE = "GPLv2"
+LIC_FILES_CHKSUM = "[file://${COMMON_LICENSE_DIR}/GPL-2.0;md5=801f80980d171dd6425610833a22dbe6]file://${COMMON_LICENSE_DIR}/GPL-2.0;md5=801f80980d171dd6425610833a22dbe6"
+
+inherit linux-kernel-base
+
+# Whilst not a module, this ensures we don't get multilib extended. (which would make no sense)
+inherit module-base
+
+S = "${STAGING_KERNEL_DIR}"
+B = "${WORKDIR}/build"
+
+# we dont need the default dependencies.
+INHIBIT_DEFAULT_DEPS = "1"
+
+KERNEL_IMAGETYPE ?= "zImage"
+KERNEL_VERSION = "${@get_kernelversion_file('${STAGING_KERNEL_BUILDDIR}')}"
+KERNEL_IMAGEDEST = "boot"
+
+KERNEL_PRIORITY ?= "${@int(d.getVar('KERNEL_VERSION',1).split('-')[0].split('+')[0].split('.')[0]) * 10000 + \
+                       int(d.getVar('KERNEL_VERSION',1).split('-')[0].split('+')[0].split('.')[1]) * 100 + \
+                       int(d.getVar('KERNEL_VERSION',1).split('-')[0].split('+')[0].split('.')[-1])}"
+
+PACKAGES = "${PN}"
+FILES_${PN} = "/${KERNEL_IMAGEDEST}/${KERNEL_IMAGETYPE}*"
+
+PKG_${PN} = "${PN}-${@legitimize_package_name('${KERNEL_VERSION}')}"
+
+PACKAGE_ARCH = "${MACHINE_ARCH}"
+
+# Skip processing of this recipe if INITRAMFS_IMAGE or INITRAMFS_IMAGE_BUNDLE
+# is not set correctly, to avoid generate a single empty package which makes
+# no sense.
+python __anonymous () {
+    if not d.getVar('INITRAMFS_IMAGE', True) or d.getVar('INITRAMFS_IMAGE_BUNDLE', True) != '1':
+        raise bb.parse.SkipPackage("Set INITRAMFS_IMAGE and INITRAMFS_IMAGE_BUNDLE to enable it")
+}
+
+# Need the output of deploy.
+do_install[depends] += "virtual/kernel:do_deploy"
+
+# We only need the packaging tasks - disable the rest
+do_fetch[noexec] = "1"
+do_unpack[noexec] = "1"
+do_patch[noexec] = "1"
+do_configure[noexec] = "1"
+do_compile[noexec] = "1"
+do_populate_sysroot[noexec] = "1"
+
+do_install() {
+	if [ ! -z "${INITRAMFS_IMAGE}" -a x"${INITRAMFS_IMAGE_BUNDLE}" = x1 ]; then
+		echo "Copying initramfs bundled kernel image from ${DEPLOY_DIR_IMAGE}..."
+		install -d ${D}/${KERNEL_IMAGEDEST}
+		install -m 0644 ${DEPLOY_DIR_IMAGE}/${KERNEL_IMAGETYPE}-initramfs-${MACHINE}.bin ${D}/${KERNEL_IMAGEDEST}/${KERNEL_IMAGETYPE}-initramfs-${KERNEL_VERSION}
+	fi
+}
+
+pkg_postinst_${PN} () {
+	update-alternatives --install /${KERNEL_IMAGEDEST}/${KERNEL_IMAGETYPE}-initramfs ${KERNEL_IMAGETYPE}-initramfs /${KERNEL_IMAGEDEST}/${KERNEL_IMAGETYPE}-initramfs-${KERNEL_VERSION} ${KERNEL_PRIORITY} || true
+}
+
+pkg_postrm_${PN} () {
+	update-alternatives --remove ${KERNEL_IMAGETYPE}-initramfs ${KERNEL_IMAGETYPE}-initramfs-${KERNEL_VERSION} || true
+}
-- 
1.9.1