[OE-core] [PATCH v2] linux-dtb: Use kernel build system to generate the dtb files

[Otavio Salvador]

As the Linux kernel, unconditionally, builds the dtc application and
it is the compatible version with the DeviceTree files shipped within
the kernel it is better to use it and the kernel build system to
generate the dtb files.

Some DeviceTree files rely on CPP and kernel headers to be able to
generate the dtb binary contents and it is harder to replicate it
outside of Linux kernel build system so we /use/ it.

To comply with these assumptions we need to use the dtb file when
calling 'make' instead of pointing to the DeviceTree source file; the
code has been made backward compatible but it is advised to move to
the new definition to avoid warnings as:

,----[ Original definition ]
| KERNEL_DEVICETREE = "${S}/arch/arm/boot/dts/imx6q-sabresd.dts"
`----

Becomes:

,----[ New definition ]
| KERNEL_DEVICETREE = "imx6q-sabresd.dtb"
`----


Signed-off-by: Otavio Salvador <otavio at ossystems.com.br>
---
Changes in v2:
- Drop debug warning left by mistake
- Improve bbwarn message (Bruce Ashfield)
- Improve commit log (Bruce Ascfield)

 meta/recipes-kernel/linux/linux-dtb.inc | 58 +++++++++++++++------------------
 1 file changed, 26 insertions(+), 32 deletions(-)

diff --git a/meta/recipes-kernel/linux/linux-dtb.inc b/meta/recipes-kernel/linux/linux-dtb.inc
index 41dd599..cebc76a 100644
--- a/meta/recipes-kernel/linux/linux-dtb.inc
+++ b/meta/recipes-kernel/linux/linux-dtb.inc
@@ -1,44 +1,38 @@
 # Support for device tree generation
 FILES_kernel-devicetree = "/${KERNEL_IMAGEDEST}/devicetree*"
-KERNEL_DEVICETREE_FLAGS ?= "-R 8 -p 0x3000"
 
 python __anonymous () {
-    devicetree = d.getVar("KERNEL_DEVICETREE", True) or ''
-    if devicetree:
-        depends = d.getVar("DEPENDS", True)
-        d.setVar("DEPENDS", "%s dtc-native" % depends)
-        packages = d.getVar("PACKAGES", True)
-        d.setVar("PACKAGES", "%s kernel-devicetree" % packages)
+    d.appendVar("PACKAGES", " kernel-devicetree")
 }
 
 do_install_append() {
 	if test -n "${KERNEL_DEVICETREE}"; then
-		for DTS_FILE in ${KERNEL_DEVICETREE}; do
-			if [ ! -f ${DTS_FILE} ]; then
-				echo "Warning: ${DTS_FILE} is not available!"
-				continue
+		for DTB in ${KERNEL_DEVICETREE}; do
+			if echo ${DTB} | grep -q '/dts/'; then
+				bbwarn "${DTB} contains the full path to the the dts file, but only the dtb name should be used."
+				DTB=`basename ${DTB} | sed 's,\.dts$,.dtb,g'`
 			fi
-			DTS_BASE_NAME=`basename ${DTS_FILE} | awk -F "." '{print $1}'`
-			DTB_NAME=`echo ${KERNEL_IMAGE_BASE_NAME} | sed "s/${MACHINE}/${DTS_BASE_NAME}/g"`
-			DTB_SYMLINK_NAME=`echo ${KERNEL_IMAGE_SYMLINK_NAME} | sed "s/${MACHINE}/${DTS_BASE_NAME}/g"`
-			dtc -I dts -O dtb ${KERNEL_DEVICETREE_FLAGS} -o ${DTS_BASE_NAME} ${DTS_FILE}
-			install -m 0644 ${DTS_BASE_NAME} ${D}/${KERNEL_IMAGEDEST}/devicetree-${DTB_SYMLINK_NAME}.dtb
+			DTB_BASE_NAME=`basename ${DTB} .dtb`
+			DTB_NAME=`echo ${KERNEL_IMAGE_BASE_NAME} | sed "s/${MACHINE}/${DTB_BASE_NAME}/g"`
+			DTB_SYMLINK_NAME=`echo ${KERNEL_IMAGE_SYMLINK_NAME} | sed "s/${MACHINE}/${DTB_BASE_NAME}/g"`
+			oe_runmake ${DTB}
+			install -m 0644 ${B}/arch/${ARCH}/boot/${DTB} ${D}/${KERNEL_IMAGEDEST}/devicetree-${DTB_SYMLINK_NAME}.dtb
 		done
 	fi
 }
 
 do_deploy_append() {
 	if test -n "${KERNEL_DEVICETREE}"; then
-		for DTS_FILE in ${KERNEL_DEVICETREE}; do
-			if [ ! -f ${DTS_FILE} ]; then
-				echo "Warning: ${DTS_FILE} is not available!"
-				continue
+		for DTB in ${KERNEL_DEVICETREE}; do
+			if echo ${DTB} | grep -q '/dts/'; then
+				bbwarn "${DTB} contains the full path to the the dts file, but only the dtb name should be used."
+				DTB=`basename ${DTB} | sed 's,\.dts$,.dtb,g'`
 			fi
-			DTS_BASE_NAME=`basename ${DTS_FILE} | awk -F "." '{print $1}'`
-			DTB_NAME=`echo ${KERNEL_IMAGE_BASE_NAME} | sed "s/${MACHINE}/${DTS_BASE_NAME}/g"`
-			DTB_SYMLINK_NAME=`echo ${KERNEL_IMAGE_SYMLINK_NAME} | sed "s/${MACHINE}/${DTS_BASE_NAME}/g"`
+			DTB_BASE_NAME=`basename ${DTB} .dtb`
+			DTB_NAME=`echo ${KERNEL_IMAGE_BASE_NAME} | sed "s/${MACHINE}/${DTB_BASE_NAME}/g"`
+			DTB_SYMLINK_NAME=`echo ${KERNEL_IMAGE_SYMLINK_NAME} | sed "s/${MACHINE}/${DTB_BASE_NAME}/g"`
 			install -d ${DEPLOYDIR}
-			install -m 0644 ${B}/${DTS_BASE_NAME} ${DEPLOYDIR}/${DTB_NAME}.dtb
+			install -m 0644 ${B}/arch/${ARCH}/boot/${DTB} ${DEPLOYDIR}/${DTB_NAME}.dtb
 			cd ${DEPLOYDIR}
 			ln -sf ${DTB_NAME}.dtb ${DTB_SYMLINK_NAME}.dtb
 			cd -
@@ -48,20 +42,20 @@ do_deploy_append() {
 
 pkg_postinst_kernel-devicetree () {
 	cd /${KERNEL_IMAGEDEST}
-	for DTS_FILE in ${KERNEL_DEVICETREE}
+	for DTB_FILE in ${KERNEL_DEVICETREE}
 	do
-		DTS_BASE_NAME=`basename ${DTS_FILE} | awk -F "." '{print $1}'`
-		DTB_SYMLINK_NAME=`echo ${KERNEL_IMAGE_SYMLINK_NAME} | sed "s/${MACHINE}/${DTS_BASE_NAME}/g"`
-		update-alternatives --install /${KERNEL_IMAGEDEST}/${DTS_BASE_NAME}.dtb ${DTS_BASE_NAME}.dtb devicetree-${DTB_SYMLINK_NAME}.dtb ${KERNEL_PRIORITY} || true
+		DTB_BASE_NAME=`basename ${DTB_FILE} | awk -F "." '{print $1}'`
+		DTB_SYMLINK_NAME=`echo ${KERNEL_IMAGE_SYMLINK_NAME} | sed "s/${MACHINE}/${DTB_BASE_NAME}/g"`
+		update-alternatives --install /${KERNEL_IMAGEDEST}/${DTB_BASE_NAME}.dtb ${DTB_BASE_NAME}.dtb devicetree-${DTB_SYMLINK_NAME}.dtb ${KERNEL_PRIORITY} || true
 	done
 }
 
 pkg_postrm_kernel-devicetree () {
 	cd /${KERNEL_IMAGEDEST}
-	for DTS_FILE in ${KERNEL_DEVICETREE}
+	for DTB_FILE in ${KERNEL_DEVICETREE}
 	do
-		DTS_BASE_NAME=`basename ${DTS_FILE} | awk -F "." '{print $1}'`
-		DTB_SYMLINK_NAME=`echo ${KERNEL_IMAGE_SYMLINK_NAME} | sed "s/${MACHINE}/${DTS_BASE_NAME}/g"`
-		update-alternatives --remove ${DTS_BASE_NAME}.dtb devicetree-${DTB_SYMLINK_NAME}.dtb ${KERNEL_PRIORITY} || true
+		DTB_BASE_NAME=`basename ${DTB_FILE} | awk -F "." '{print $1}'`
+		DTB_SYMLINK_NAME=`echo ${KERNEL_IMAGE_SYMLINK_NAME} | sed "s/${MACHINE}/${DTB_BASE_NAME}/g"`
+		update-alternatives --remove ${DTB_BASE_NAME}.dtb devicetree-${DTB_SYMLINK_NAME}.dtb ${KERNEL_PRIORITY} || true
 	done
 }
-- 
1.8.4.rc1