Get rid of the static kernel configuration files

With a backported patch from the OpenWrt trunk, it is now easy to generate an
equivalent configuration using CONFIG_ALL_KMODS.

The build will take a bit longer because all kernel module packages are actually
built even when they are not included in the image, but adding new targets
becomes a lot easier.

Also, related documentation updates and fixes.

docs/dev/hardware.rst

@@ -73,30 +73,23 @@ won't run correctly without some adjustments, so better double check that everyt
 Add support to the build system
 '''''''''''''''''''''''''''''''
 A directory for the new target must be created under ``targets``, and it must be added
-to ``targets/targets.mk``. In the new target directory, four files must be created:
+to ``targets/targets.mk``. In the new target directory, three files must be created:
 
 * config
-* kernel-config
-* kernel-vermagic
 * profiles.mk
+* vermagic
 
-The file ``config`` can be used to add additional, target-specific options to the OpenWrt config. If such options
-aren't necessary, it can be left empty. For ``profiles.mk``, see :ref:`hardware-adding-profiles`.
+The file ``config`` can be used to add additional, target-specific options to the OpenWrt config. It
+must at least select the correct target and subtarget. For ``profiles.mk``, see :ref:`hardware-adding-profiles`.
 
-The files ``kernel-config`` and ``kernel-vermagic`` must have the correct content so kernel modules from the upstream repositories
-can be easily installed. The OpenWrt version a Gluon release is based on is defined by the upstream package repo URL in ``include/gluon.mk``
-(in the variable ``CONFIG_VERSION_REPO``); at the time this documentation was written, this was ``barrier_breaker/14.07-rc3``; whenever
-the package repo is updated, all ``kernel-config`` and ``kernel-vermagic`` files must be updated as well.
+The files ``vermagic`` must have the correct content so kernel modules from the upstream repositories
+can be installed without dependency issues. The OpenWrt version a Gluon release is based on is defined by the upstream package repo URL in ``include/gluon.mk``
+(in the variable ``CONFIG_VERSION_REPO``); at the time this documentation was written, this was ``barrier_breaker/14.07``; whenever
+the package repo is updated, all ``vermagic`` files must be updated as well.
 
-The file ``kernel-vermagic`` just contains a hash which is part of the version number of the kernel package. So in the case of ``ar71xx-generic`` on
-``barrier_breaker/14.07-rc3``, we look in the directory ``https://downloads.openwrt.org/barrier_breaker/14.07-rc3/ar71xx/generic/packages/`` and
-find that the kernel package is called ``kernel_3.10.49-1-94831e5bcf361d1c03e87a15e152b0e8_ar71xx.ipk``. This makes the ``kernel-vermagic`` the
-string ``94831e5bcf361d1c03e87a15e152b0e8``.
-
-For ``kernel-config``, the OpenWrt image builder must be downloaded. Again, for ``ar71xx-generic`` on
-``barrier_breaker/14.07-rc3``, we download ``OpenWrt-SDK-ar71xx-for-linux-x86_64-gcc-4.8-linaro_uClibc-0.9.33.2.tar.bz2``
-from ``https://downloads.openwrt.org/barrier_breaker/14.07-rc3/ar71xx/generic/``. After unpacking it, we use the file
-``OpenWrt-ImageBuilder-ar71xx_generic-for-linux-x86_64/build_dir/target-mips_34kc_uClibc-0.9.33.2/linux-ar71xx_generic/linux-3.10.49/.config``
-as our ``kernel-config``.
+The content is a hash which is part of the version number of the kernel package. So in the case of ``ar71xx-generic`` on
+``barrier_breaker``, we look for the kernel package in the directory ``https://downloads.openwrt.org/barrier_breaker/14.07/ar71xx/generic/packages/base/``.
+As the kernel package is called ``kernel_3.10.49-1-0114c71ed85677c9c1e4911437af4743_ar71xx.ipk``, the correct ``vermagic`` string
+is ``0114c71ed85677c9c1e4911437af4743``.
 
 After this, is should be sufficient to call ``make GLUON_TARGET=<target>-<subtarget>`` to build the images for the new target.

include/Makefile.target

@@ -1,10 +1,6 @@
 override define Kernel/Configure
-	cp $(GLUONDIR)/targets/$(GLUON_TARGET)/kernel-config $(LINUX_DIR)/.config
-	+$(MAKE) $(KERNEL_MAKEOPTS) oldnoconfig
-	$(call Kernel/SetInitramfs)
-	rm -rf $(KERNEL_BUILD_DIR)/modules
-	+[ -d $(LINUX_DIR)/user_headers ] || $(MAKE) $(KERNEL_MAKEOPTS) INSTALL_HDR_PATH=$(LINUX_DIR)/user_headers headers_install
-	cp $(GLUONDIR)/targets/$(GLUON_TARGET)/kernel-vermagic $(LINUX_DIR)/.vermagic
+	$(call Kernel/Configure/Default)
+	cp $(GLUONDIR)/targets/$(GLUON_TARGET)/vermagic $(LINUX_DIR)/.vermagic
 endef
 
 # The Makefile included here is $(TOPDIR)/target/linux/$(BOARD)/Makefile

include/config

@@ -1,3 +1,5 @@
+CONFIG_ALL_KMODS=y
+
 CONFIG_IMAGEOPT=y
 # CONFIG_PER_FEED_REPO is not set
 

patches/openwrt/0029-buildroot-make-it-easier-to-build-all-kmods.patch

@@ -0,0 +1,57 @@
+From: Matthias Schiffer <mschiffer@universe-factory.net>
+Date: Mon, 16 Mar 2015 13:23:34 +0100
+Subject: buildroot: make it easier to build all kmods
+
+Split out kmods from ALL to make it easier to create local builds that
+are compatible kmod-wise with releases.
+
+Signed-off-by: Jonas Gorski <jogo@openwrt.org>
+
+diff --git a/config/Config-build.in b/config/Config-build.in
+index 371ae76..8b0ebbf 100644
+--- a/config/Config-build.in
++++ b/config/Config-build.in
+@@ -6,8 +6,12 @@
+ 
+ menu "Global build settings"
+ 
++	config ALL_KMODS
++		bool "Select all kernel module packages by default"
++		default ALL
++
+ 	config ALL
+-		bool "Select all packages by default"
++		bool "Select all userspace packages by default"
+ 		default n
+ 
+ 	comment "General build options"
+diff --git a/include/version.mk b/include/version.mk
+index 2fd605f..f6c0fe2 100644
+--- a/include/version.mk
++++ b/include/version.mk
+@@ -50,7 +50,7 @@ $(lastword $(subst :, ,$(1)))
+ endef
+ 
+ VERSION_TAINT_SPECS := \
+-	-ALL:no-all \
++	-ALL_KMODS:no-all \
+ 	-IPV6:no-ipv6 \
+ 	+USE_EGLIBC:eglibc \
+ 	+USE_MKLIBS:mklibs \
+diff --git a/scripts/metadata.pl b/scripts/metadata.pl
+index 79f930c..4eecb0c 100755
+--- a/scripts/metadata.pl
++++ b/scripts/metadata.pl
+@@ -574,7 +574,11 @@ sub print_package_config_category($) {
+ 			print "\t\t".($pkg->{tristate} ? 'tristate' : 'bool')." $title\n";
+ 			print "\t\tdefault y if DEFAULT_".$pkg->{name}."\n";
+ 			unless ($pkg->{hidden}) {
+-				$pkg->{default} ||= "m if ALL";
++				if ($pkg->{name} =~ /^kmod-/) {
++					$pkg->{default} ||= "m if ALL_KMODS";
++				} else {
++					$pkg->{default} ||= "m if ALL";
++				}
+ 			}
+ 			if ($pkg->{default}) {
+ 				foreach my $default (split /\s*,\s*/, $pkg->{default}) {