kernel: Fix non linux-yocto builds

After the recent kernel changes, non linux-yocto builds stopped working
properly for two reasons:

a) ${S} was being reset to ${WORKDIR}/git for example and STAGING_KERNEL_DIR
   did not contain the source

b) Most builds were using ${B} == ${S}

This patch adds a fixup to the unpack function to handle the case where
${S} != ${STAGING_KERNEL_DIR} and also set up the infrastrcture so that
B != S for kernel builds from now on. The kernel build system is one of the
best for supporting this and there is no good reason not to take advantage
of it.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 25 insertions, 4 deletions

diff --git a/meta/classes/kernel.bbclass b/meta/classes/kernel.bbclass
index c9e1c363e8..5cabc2ce1c 100644
--- a/meta/classes/kernel.bbclass
+++ b/meta/classes/kernel.bbclass
@@ -3,9 +3,10 @@ inherit linux-kernel-base kernel-module-split
 PROVIDES += "virtual/kernel"
 DEPENDS += "virtual/${TARGET_PREFIX}binutils virtual/${TARGET_PREFIX}gcc kmod-native depmodwrapper-cross bc-native"
 
-S = "${STAGING_DIR_TARGET}/${KERNEL_SRC_PATH}"
-
-do_unpack[cleandirs] = "${S}"
+S = "${STAGING_KERNEL_DIR}"
+B = "${WORKDIR}/build"
+KBUILD_OUTPUT = "${B}"
+OE_TERMINAL_EXPORTS += "KBUILD_OUTPUT"
 
 # we include gcc above, we dont need virtual/libc
 INHIBIT_DEFAULT_DEPS = "1"
@@ -35,6 +36,22 @@ python __anonymous () {
         d.appendVarFlag('do_configure', 'depends', ' ${INITRAMFS_TASK}')
 }
 
+# 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
+# the symlink.
+do_unpack[cleandirs] += " ${S} ${STAGING_KERNEL_DIR} ${B}"
+base_do_unpack_append () {
+    s = d.getVar("S", True)
+    kernsrc = d.getVar("STAGING_KERNEL_DIR", True)
+    if s != kernsrc:
+        bb.utils.mkdirhier(kernsrc)
+        bb.utils.remove(kernsrc, recurse=True)
+        import subprocess
+        subprocess.call(d.expand("mv ${S} ${STAGING_KERNEL_DIR}"), shell=True)
+        os.symlink(kernsrc, s)
+}
+
 inherit kernel-arch deploy
 
 PACKAGES_DYNAMIC += "^kernel-module-.*"
@@ -255,7 +272,7 @@ python sysroot_stage_all () {
     oe.path.copyhardlinktree(d.expand("${D}${KERNEL_SRC_PATH}"), d.expand("${SYSROOT_DESTDIR}${KERNEL_SRC_PATH}"))
 }
 
-KERNEL_CONFIG_COMMAND ?= "oe_runmake_call oldnoconfig || yes '' | oe_runmake oldconfig"
+KERNEL_CONFIG_COMMAND ?= "oe_runmake_call -C ${S} O=${B} oldnoconfig || yes '' | oe_runmake -C ${S} O=${B} oldconfig"
 
 kernel_do_configure() {
 	# fixes extra + in /lib/modules/2.6.37+
@@ -264,6 +281,10 @@ kernel_do_configure() {
 	# $ make kernelrelease => 2.6.37+
 	touch ${B}/.scmversion ${S}/.scmversion
 
+	if [ "${S}" != "${B}" ] && [ -f "${S}/.config" ] && [ ! -f "${B}/.config" ]; then
+		mv "${S}/.config" "${B}/.config"
+	fi
+
 	# Copy defconfig to .config if .config does not exist. This allows
 	# recipes to manage the .config themselves in do_configure_prepend().
 	if [ -f "${WORKDIR}/defconfig" ] && [ ! -f "${B}/.config" ]; then