[OE-core] [PATCH 4/8] kernel: Pull uImage generation into separate class

[Marek Vasut]

Pull the uImage image format generation from kernel.bbclass into
a separate kernel-uimage.bbclass. The recipes which now need to
generate an uImage will have to inherit kernel-uimage instead of
kernel class.

Signed-off-by: Marek Vasut <marex at denx.de>
Cc: Richard Purdie <richard.purdie at linuxfoundation.org>
Cc: Koen Kooi <koen at dominion.thruhere.net>
Cc: Paul Eggleton <paul.eggleton at linux.intel.com>
Cc: Ross Burton <ross.burton at intel.com>
Cc: Bruce Ashfield <bruce.ashfield at windriver.com>
---
 meta/classes/kernel-uimage.bbclass | 48 +++++++++++++++++++++++++++++++++
 meta/classes/kernel.bbclass        | 55 +++++++-------------------------------
 2 files changed, 58 insertions(+), 45 deletions(-)
 create mode 100644 meta/classes/kernel-uimage.bbclass

NOTE: The "inherit kernel-uimage" in kernel.bbclass should be changed to
      something like "inherit kernel-${@d.getVar("KERNEL_IMAGETYPE", True).lower()}"
      but the problem is that I only want to perform the inheritance for uimage
      and fitimage, the other image types don't need to inherit any additional
      special stuff.
      Paul suggested I can do "inherit <empty here>". This would at least let me
      implement a python function which returns either "kernel-uimage",
      "kernel-fitimage" or "" and based on that, I could inherit the particular
      image type specifics into kernel.bbclass.
      What I don't know how to implement well is this function which returns
      those three strings based on the KERNEL_IMAGETYPE. What I would like to
      avoid is encoding those strings explicitly into the function, since that
      would force each new kernel image format to also edit this function in
      kernel.bbclass . Apparently, checking whether class exists and inheriting
      it only if it does is also not a simple task.
      
      The conditional inheritance here would also allow me to remove all those
      if [ $KERNEL_IMAGETYPE = "uImage" ] checks from kernel-uimage.bbclass and
      kernel-fitimage.bbclass, since those classes would be inherited only if
      the matching imagetype would be selected.

diff --git a/meta/classes/kernel-uimage.bbclass b/meta/classes/kernel-uimage.bbclass
new file mode 100644
index 0000000..8a3efc6
--- /dev/null
+++ b/meta/classes/kernel-uimage.bbclass
@@ -0,0 +1,48 @@
+python __anonymous () {
+    kerneltype = d.getVar('KERNEL_IMAGETYPE', True)
+    if kerneltype == 'uImage':
+        depends = d.getVar("DEPENDS", True)
+        depends = "%s u-boot-mkimage-native" % depends
+        d.setVar("DEPENDS", depends)
+}
+
+uboot_prep_kimage() {
+	if test -e arch/${ARCH}/boot/compressed/vmlinux ; then
+		vmlinux_path="arch/${ARCH}/boot/compressed/vmlinux"
+		linux_suffix=""
+		linux_comp="none"
+	else
+		vmlinux_path="vmlinux"
+		linux_suffix=".gz"
+		linux_comp="gzip"
+	fi
+
+	${OBJCOPY} -O binary -R .note -R .comment -S "${vmlinux_path}" linux.bin
+
+	if [ "${linux_comp}" != "none" ] ; then
+		rm -f linux.bin
+		gzip -9 linux.bin
+		mv -f "linux.bin${linux_suffix}" linux.bin
+	fi
+
+	echo "${linux_comp}"
+}
+
+do_uboot_mkimage() {
+	if test "x${KERNEL_IMAGETYPE}" = "xuImage" ; then
+		if test "x${KEEPUIMAGE}" != "xyes" ; then
+			uboot_prep_kimage
+
+			ENTRYPOINT=${UBOOT_ENTRYPOINT}
+			if test -n "${UBOOT_ENTRYSYMBOL}"; then
+				ENTRYPOINT=`${HOST_PREFIX}nm ${S}/vmlinux | \
+					awk '$3=="${UBOOT_ENTRYSYMBOL}" {print $1}'`
+			fi
+
+			uboot-mkimage -A ${UBOOT_ARCH} -O linux -T kernel -C "${linux_comp}" -a ${UBOOT_LOADADDRESS} -e $ENTRYPOINT -n "${DISTRO_NAME}/${PV}/${MACHINE}" -d linux.bin arch/${ARCH}/boot/uImage
+			rm -f linux.bin
+		fi
+	fi
+}
+
+addtask uboot_mkimage before do_install after do_compile
diff --git a/meta/classes/kernel.bbclass b/meta/classes/kernel.bbclass
index 2895e5e..9723be2 100644
--- a/meta/classes/kernel.bbclass
+++ b/meta/classes/kernel.bbclass
@@ -20,10 +20,6 @@ python __anonymous () {
     import re
 
     kerneltype = d.getVar('KERNEL_IMAGETYPE', True)
-    if kerneltype == 'uImage':
-        depends = d.getVar("DEPENDS", True)
-        depends = "%s u-boot-mkimage-native" % depends
-        d.setVar("DEPENDS", depends)
 
     d.setVar("KERNEL_IMAGETYPE_FOR_MAKE", re.sub(r'\.gz$', '', kerneltype))
 
@@ -40,6 +36,16 @@ python __anonymous () {
         d.appendVarFlag('do_configure', 'depends', ' ${INITRAMFS_TASK}')
 }
 
+# Here we pull in all various kernel image types which we support.
+#
+# In case you're wondering why kernel.bbclass inherits the other image
+# types instead of the other way around, the reason for that is to
+# maintain compatibility with various currently existing meta-layers.
+# By pulling in the various kernel image types here, we retain the
+# original behavior of kernel.bbclass, so no meta-layers should get
+# broken.
+inherit kernel-uimage
+
 # Old style kernels may set ${S} = ${WORKDIR}/git for example
 # We need to move these over to STAGING_KERNEL_DIR. We can't just
 # create the symlink in advance as the git fetcher can't cope with
@@ -432,47 +438,6 @@ MODULE_TARBALL_BASE_NAME ?= "${MODULE_IMAGE_BASE_NAME}.tgz"
 MODULE_TARBALL_SYMLINK_NAME ?= "modules-${MACHINE}.tgz"
 MODULE_TARBALL_DEPLOY ?= "1"
 
-uboot_prep_kimage() {
-	if test -e arch/${ARCH}/boot/compressed/vmlinux ; then
-		vmlinux_path="arch/${ARCH}/boot/compressed/vmlinux"
-		linux_suffix=""
-		linux_comp="none"
-	else
-		vmlinux_path="vmlinux"
-		linux_suffix=".gz"
-		linux_comp="gzip"
-	fi
-
-	${OBJCOPY} -O binary -R .note -R .comment -S "${vmlinux_path}" linux.bin
-
-	if [ "${linux_comp}" != "none" ] ; then
-		rm -f linux.bin
-		gzip -9 linux.bin
-		mv -f "linux.bin${linux_suffix}" linux.bin
-	fi
-
-	echo "${linux_comp}"
-}
-
-do_uboot_mkimage() {
-	if test "x${KERNEL_IMAGETYPE}" = "xuImage" ; then 
-		if test "x${KEEPUIMAGE}" != "xyes" ; then
-			uboot_prep_kimage
-
-			ENTRYPOINT=${UBOOT_ENTRYPOINT}
-			if test -n "${UBOOT_ENTRYSYMBOL}"; then
-				ENTRYPOINT=`${HOST_PREFIX}nm ${S}/vmlinux | \
-					awk '$3=="${UBOOT_ENTRYSYMBOL}" {print $1}'`
-			fi
-
-			uboot-mkimage -A ${UBOOT_ARCH} -O linux -T kernel -C "${linux_comp}" -a ${UBOOT_LOADADDRESS} -e $ENTRYPOINT -n "${DISTRO_NAME}/${PV}/${MACHINE}" -d linux.bin arch/${ARCH}/boot/uImage
-			rm -f linux.bin
-		fi
-	fi
-}
-
-addtask uboot_mkimage before do_install after do_compile
-
 kernel_do_deploy() {
 	install -m 0644 ${KERNEL_OUTPUT} ${DEPLOYDIR}/${KERNEL_IMAGE_BASE_NAME}.bin
 	if [ ${MODULE_TARBALL_DEPLOY} = "1" ] && (grep -q -i -e '^CONFIG_MODULES=y$' .config); then
-- 
2.1.4