From 487e21cff69b30b404146b2ffb46959a728a4002 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Sat, 3 Apr 2010 18:46:46 +0200 Subject: New, simpler, infrastructure for building the Linux kernel This patch introduces a single, simple, infrastructure to build the Linux kernel. The configuration is limited to : * Kernel version: a fixed recent stable version, same as kernel headers version (for internal toolchains only), custom stable version, or custom tarball URL * Kernel patch: either a local file, directory or an URL * Kernel configuration: either the name of a defconfig or the location of a custom configuration file * Kernel image: either uImage, bzImage, zImage or vmlinux. Signed-off-by: Thomas Petazzoni --- linux/linux.mk | 118 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+) create mode 100644 linux/linux.mk (limited to 'linux/linux.mk') diff --git a/linux/linux.mk b/linux/linux.mk new file mode 100644 index 000000000..3e91ecaba --- /dev/null +++ b/linux/linux.mk @@ -0,0 +1,118 @@ +############################################################################### +# +# Linux kernel 2.6 target +# +############################################################################### +LINUX26_VERSION=$(call qstrip,$(BR2_LINUX_KERNEL_VERSION)) + +# Compute LINUX26_SOURCE and LINUX26_SITE from the configuration +ifeq ($(LINUX26_VERSION),custom) +LINUX26_TARBALL:=$(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_TARBALL_LOCATION)) +LINUX26_SITE:=$(dir $(LINUX26_TARBALL)) +LINUX26_SOURCE:=$(notdir $(LINUX26_TARBALL)) +else +LINUX26_SOURCE:=linux-$(LINUX26_VERSION).tar.bz2 +LINUX26_SITE:=$(BR2_KERNEL_MIRROR)/linux/kernel/v2.6/ +endif + +LINUX26_DIR:=$(BUILD_DIR)/linux-$(LINUX26_VERSION) +LINUX26_PATCH=$(call qstrip,$(BR2_LINUX_KERNEL_PATCH)) + +LINUX26_MAKE_FLAGS = \ + HOSTCC="$(HOSTCC)" \ + HOSTCFLAGS="$(HOSTCFLAGS)" \ + ARCH=$(KERNEL_ARCH) \ + INSTALL_MOD_PATH=$(TARGET_DIR) \ + CROSS_COMPILE=$(TARGET_CROSS) \ + LDFLAGS="$(TARGET_LDFLAGS)" \ + LZMA="$(LZMA)" + +# Get the real Linux version, which tells us where kernel modules are +# going to be installed in the target filesystem. +LINUX26_VERSION_PROBED = $(shell $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(LINUX26_DIR) --no-print-directory -s kernelrelease) + +ifeq ($(BR2_LINUX_KERNEL_UIMAGE),y) +LINUX26_IMAGE_NAME=uImage +LINUX26_DEPENDENCIES+=$(MKIMAGE) +else ifeq ($(BR2_LINUX_KERNEL_BZIMAGE),y) +LINUX26_IMAGE_NAME=bzImage +else ifeq ($(BR2_LINUX_KERNEL_ZIMAGE),y) +LINUX26_IMAGE_NAME=zImage +else ifeq ($(BR2_LINUX_KERNEL_VMLINUX),y) +LINUX26_IMAGE_NAME=vmlinux.bin +endif + +LINUX26_IMAGE_PATH=$(LINUX26_DIR)/arch/$(KERNEL_ARCH)/boot/$(LINUX26_IMAGE_NAME) + +# Download +$(LINUX26_DIR)/.stamp_downloaded: + @$(call MESSAGE,"Downloading kernel") + $(call DOWNLOAD,$(LINUX26_SITE),$(LINUX26_SOURCE)) +ifneq ($(filter ftp://% http://%,$(LINUX26_PATCH)),) + $(call DOWNLOAD,$(dir $(LINUX26_PATCH)),$(notdir $(LINUX26_PATCH))) +endif + mkdir -p $(@D) + touch $@ + +# Extraction +$(LINUX26_DIR)/.stamp_extracted: $(LINUX26_DIR)/.stamp_downloaded + @$(call MESSAGE,"Extracting kernel") + mkdir -p $(@D) + $(Q)$(INFLATE$(suffix $(LINUX26_SOURCE))) $(DL_DIR)/$(LINUX26_SOURCE) | \ + tar -C $(@D) $(TAR_STRIP_COMPONENTS)=1 $(TAR_OPTIONS) - + $(Q)touch $@ + +# Patch +$(LINUX26_DIR)/.stamp_patched: $(LINUX26_DIR)/.stamp_extracted + @$(call MESSAGE,"Patching kernel") +ifneq ($(LINUX26_PATCH),) +ifneq ($(filter ftp://% http://%,$(LINUX26_PATCH)),) + toolchain/patch-kernel.sh $(@D) $(DL_DIR) $(notdir $(LINUX26_PATCH)) +else ifeq ($(shell test -d $(LINUX26_PATCH) && echo "dir"),dir) + toolchain/patch-kernel.sh $(@D) $(LINUX26_PATCH) linux-\*.patch +else + toolchain/patch-kernel.sh $(@D) $(dir $(LINUX26_PATCH)) $(notdir $(LINUX26_PATCH)) +endif +endif + $(Q)touch $@ + + +# Configuration +$(LINUX26_DIR)/.stamp_configured: $(LINUX26_DIR)/.stamp_patched + @$(call MESSAGE,"Configuring kernel") +ifeq ($(BR2_LINUX_KERNEL_USE_DEFCONFIG),y) + $(TARGET_MAKE_ENV) $(MAKE1) $(LINUX26_MAKE_FLAGS) -C $(@D) $(call qstrip,$(BR2_LINUX_KERNEL_DEFCONFIG))_defconfig +else ifeq ($(BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG),y) + cp $(BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE) $(@D)/.config +endif + $(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) oldconfig + $(Q)touch $@ + +# Compilation +$(LINUX26_DIR)/.stamp_compiled: $(LINUX26_DIR)/.stamp_configured + @$(call MESSAGE,"Compiling kernel") + $(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) $(LINUX26_IMAGE_NAME) + @if [ $(shell grep -c "CONFIG_MODULES=y" $(LINUX26_DIR)/.config) != 0 ] ; then \ + $(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) modules ; \ + fi + $(Q)touch $@ + +# Installation +$(LINUX26_DIR)/.stamp_installed: $(LINUX26_DIR)/.stamp_compiled + @$(call MESSAGE,"Installing kernel") + cp $(LINUX26_IMAGE_PATH) $(BINARIES_DIR) + # Install modules and remove symbolic links pointing to build + # directories, not relevant on the target + @if [ $(shell grep -c "CONFIG_MODULES=y" $(LINUX26_DIR)/.config) != 0 ] ; then \ + $(TARGET_MAKE_ENV) $(MAKE1) $(LINUX26_MAKE_FLAGS) -C $(@D) \ + INSTALL_MOD_PATH=$(TARGET_DIR) modules_install ; \ + rm -f $(TARGET_DIR)/lib/modules/$(LINUX26_VERSION_PROBED)/build ; \ + rm -f $(TARGET_DIR)/lib/modules/$(LINUX26_VERSION_PROBED)/source ; \ + fi + $(Q)touch $@ + +linux26: $(LINUX26_DEPENDENCIES) $(LINUX26_DIR)/.stamp_installed + +ifeq ($(BR2_LINUX_KERNEL),y) +TARGETS+=linux26 +endif -- cgit v1.2.3 From dc4d5647a528b366d88d4c6f94405c12a1aa0ebf Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Sat, 5 Jun 2010 21:26:18 +0200 Subject: linux: Add dependency on host-module-init-tools In order to not depend on module init tools being installed on the development environment of the Buildroot user, let's build module init tools for the host. Signed-off-by: Thomas Petazzoni --- linux/linux.mk | 2 +- package/module-init-tools/module-init-tools.mk | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) (limited to 'linux/linux.mk') diff --git a/linux/linux.mk b/linux/linux.mk index 3e91ecaba..8b83e3066 100644 --- a/linux/linux.mk +++ b/linux/linux.mk @@ -111,7 +111,7 @@ $(LINUX26_DIR)/.stamp_installed: $(LINUX26_DIR)/.stamp_compiled fi $(Q)touch $@ -linux26: $(LINUX26_DEPENDENCIES) $(LINUX26_DIR)/.stamp_installed +linux26: host-module-init-tools $(LINUX26_DEPENDENCIES) $(LINUX26_DIR)/.stamp_installed ifeq ($(BR2_LINUX_KERNEL),y) TARGETS+=linux26 diff --git a/package/module-init-tools/module-init-tools.mk b/package/module-init-tools/module-init-tools.mk index 3e8b06bde..ea7c014dc 100644 --- a/package/module-init-tools/module-init-tools.mk +++ b/package/module-init-tools/module-init-tools.mk @@ -17,3 +17,5 @@ MODULE_INIT_TOOLS_AUTORECONF=YES HOST_MODULE_INIT_TOOLS_AUTORECONF=YES $(eval $(call AUTOTARGETS,package,module-init-tools)) +$(eval $(call AUTOTARGETS,package,module-init-tools,host)) + -- cgit v1.2.3 From 100c09a53b8806b2281a93ad21744d26f68bcc6b Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Tue, 8 Jun 2010 13:56:19 +0200 Subject: linux: adjust kernel config according to the Buildroot configuration We only adjust the configuration or ARM EABI and IPv6. The (more complicated) initramfs case is handled in a separate commit. The user is expected to take care of all other configuration details (like having Netfilter enabled to make iptables work, etc.) Signed-off-by: Thomas Petazzoni --- linux/linux.mk | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'linux/linux.mk') diff --git a/linux/linux.mk b/linux/linux.mk index 8b83e3066..71d961603 100644 --- a/linux/linux.mk +++ b/linux/linux.mk @@ -84,6 +84,16 @@ ifeq ($(BR2_LINUX_KERNEL_USE_DEFCONFIG),y) $(TARGET_MAKE_ENV) $(MAKE1) $(LINUX26_MAKE_FLAGS) -C $(@D) $(call qstrip,$(BR2_LINUX_KERNEL_DEFCONFIG))_defconfig else ifeq ($(BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG),y) cp $(BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE) $(@D)/.config +endif +ifeq ($(BR2_ARM_EABI),y) + $(call KCONFIG_ENABLE_OPT,CONFIG_AEABI,$(@D)/.config) +else + $(call KCONFIG_DISABLE_OPT,CONFIG_AEABI,$(@D)/.config) +endif +ifeq ($(BR2_INET_IPV6),y) + $(call KCONFIG_ENABLE_OPT,CONFIG_IPV6,$(@D)/.config) +else + $(call KCONFIG_DISABLE_OPT,CONFIG_IPV6,$(@D)/.config) endif $(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) oldconfig $(Q)touch $@ -- cgit v1.2.3 From 4944e8c883efd0e11cc9e7585905e89941eb825b Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Sun, 13 Jun 2010 19:18:34 +0200 Subject: linux: add support for linux26-{menuconfig,xconfig,gconfig} targets These targets allow the user to customize the configuration of the Linux kernel. After changing the kernel configuration, the next time the user runs "make", the kernel is rebuilt to take into account the new configuration (not rebuilt from scratch). Signed-off-by: Thomas Petazzoni --- linux/linux.mk | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'linux/linux.mk') diff --git a/linux/linux.mk b/linux/linux.mk index 71d961603..d1f1842f7 100644 --- a/linux/linux.mk +++ b/linux/linux.mk @@ -98,8 +98,9 @@ endif $(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) oldconfig $(Q)touch $@ -# Compilation -$(LINUX26_DIR)/.stamp_compiled: $(LINUX26_DIR)/.stamp_configured +# Compilation. We make sure the kernel gets rebuilt when the +# configuration has changed. +$(LINUX26_DIR)/.stamp_compiled: $(LINUX26_DIR)/.stamp_configured $(LINUX26_DIR)/.config @$(call MESSAGE,"Compiling kernel") $(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) $(LINUX26_IMAGE_NAME) @if [ $(shell grep -c "CONFIG_MODULES=y" $(LINUX26_DIR)/.config) != 0 ] ; then \ @@ -123,6 +124,9 @@ $(LINUX26_DIR)/.stamp_installed: $(LINUX26_DIR)/.stamp_compiled linux26: host-module-init-tools $(LINUX26_DEPENDENCIES) $(LINUX26_DIR)/.stamp_installed +linux26-menuconfig linux26-xconfig linux26-gconfig: $(LINUX26_DIR)/.stamp_configured + $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(LINUX26_DIR) $(subst linux26-,,$@) + ifeq ($(BR2_LINUX_KERNEL),y) TARGETS+=linux26 endif -- cgit v1.2.3 From f507921d391bb2578261a9e45c003e72302dc67a Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Sun, 13 Jun 2010 19:19:38 +0200 Subject: linux: add support for initramfs In Buildroot, the kernel is built and installed *before* the root filesystems are built. This allows the root filesystem to correctly contain the kernel modules that have been installed. However, in the initramfs case, the root filesystem is part of the kernel. Therefore, the kernel should be built *after* the root filesystem (which, in the initramfs case simply builds a text file listing all files/directories/devices/symlinks that should be part of the initramfs). However, this isn't possible as the initramfs text file would lack all kernel modules. So, the solution choosen here is to keep the normal order: kernel is built before the root filesystem is generated, and to add a little quirk to retrigger a kernel compilation after the root filesystem generation. To do so, we add a ROOTFS_$(FSTYPE)_POST_TARGETS variable to the fs/common.mk infrastructure. This allows individual filesystems to set a target name that we should depend on *after* generating the root filesystem itself (contrary to normal ROOTFS_$(FSTYPE)_DEPENDENCIES, on which we depend *before* generating the root filesystem). The initramfs code in fs/initramfs/initramfs.mk uses this to add a dependency on 'linux26-rebuild-with-initramfs'. In linux/linux.mk, we do various things : * If BR2_TARGET_ROOTFS_INITRAMFS is enabled (i.e if initramfs is enabled as a root filesystem type), then we create an empty rootfs.initramfs file (remember that at this point, the root filesystem hasn't been generated) and we adjust the kernel configuration to include an initramfs. Of course, in the initial kernel build, this initramfs will be empty. * In the linux26-rebuild-with-initramfs target, we retrigger a compilation of the kernel image, after removing the initramfs in the kernel sources to make sure it gets properly rebuilt (we've experienced cases were modifying the rootfs.initramfs file wouldn't retrigger the generation of the initramfs at the kernel level). This is fairly quirky, but initramfs really is a special case, so in one way or another, we need a little quirk to solve its specialness. Signed-off-by: Thomas Petazzoni --- fs/common.mk | 6 +++++- fs/initramfs/initramfs.mk | 2 ++ linux/linux.mk | 30 ++++++++++++++++++++++++++++++ 3 files changed, 37 insertions(+), 1 deletion(-) (limited to 'linux/linux.mk') diff --git a/fs/common.mk b/fs/common.mk index 50dc97425..74e9ce060 100644 --- a/fs/common.mk +++ b/fs/common.mk @@ -19,6 +19,10 @@ # ROOTFS_$(FSTYPE)_POST_GEN_HOOKS, a list of hooks to call after # generating the filesystem image # +# ROOTFS_$(FSTYPE)_POST_TARGETS, the list of targets that should be +# run after running the main filesystem target. This is useful for +# initramfs, to rebuild the kernel once the initramfs is generated. +# # In terms of configuration option, this macro assumes that the # BR2_TARGET_ROOTFS_$(FSTYPE) config option allows to enable/disable # the generation of a filesystem image of a particular type. If @@ -60,7 +64,7 @@ endif $(1)-root-show-depends: @echo $(ROOTFS_$(2)_DEPENDENCIES) host-fakeroot host-makedevs $(if $(BR2_TARGET_ROOTFS_$(2)_LZMA),host-lzma) -$(1)-root: $(BINARIES_DIR)/rootfs.$(1) +$(1)-root: $(BINARIES_DIR)/rootfs.$(1) $(ROOTFS_$(2)_POST_TARGETS) ifeq ($$(BR2_TARGET_ROOTFS_$(2)),y) TARGETS += $(1)-root diff --git a/fs/initramfs/initramfs.mk b/fs/initramfs/initramfs.mk index 3e8156761..e6d004e9b 100644 --- a/fs/initramfs/initramfs.mk +++ b/fs/initramfs/initramfs.mk @@ -23,4 +23,6 @@ define ROOTFS_INITRAMFS_CMD $(SHELL) fs/initramfs/gen_initramfs_list.sh -u 0 -g 0 $(TARGET_DIR) > $$@ endef +ROOTFS_INITRAMFS_POST_TARGETS += linux26-rebuild-with-initramfs + $(eval $(call ROOTFS_TARGET,initramfs)) \ No newline at end of file diff --git a/linux/linux.mk b/linux/linux.mk index d1f1842f7..593a1b40a 100644 --- a/linux/linux.mk +++ b/linux/linux.mk @@ -94,6 +94,19 @@ ifeq ($(BR2_INET_IPV6),y) $(call KCONFIG_ENABLE_OPT,CONFIG_IPV6,$(@D)/.config) else $(call KCONFIG_DISABLE_OPT,CONFIG_IPV6,$(@D)/.config) +endif +ifeq ($(BR2_TARGET_ROOTFS_INITRAMFS),y) + # As the kernel gets compiled before root filesystems are + # built, we create a fake initramfs file list. It'll be + # replaced later by the real list, and the kernel will be + # rebuilt using the linux26-rebuild-with-initramfs target. + touch $(BINARIES_DIR)/rootfs.initramfs + $(call KCONFIG_ENABLE_OPT,CONFIG_BLK_DEV_INITRD,$(@D)/.config) + $(call KCONFIG_SET_OPT,CONFIG_INITRAMFS_SOURCE,\"$(BINARIES_DIR)/rootfs.initramfs\",$(@D)/.config) + $(call KCONFIG_ENABLE_OPT,CONFIG_INITRAMFS_COMPRESSION_GZIP,$(@D)/.config) +else + $(call KCONFIG_DISABLE_OPT,CONFIG_BLK_DEV_INITRD,$(@D)/.config) + $(call KCONFIG_SET_OPT,CONFIG_INITRAMFS_SOURCE,\"\",$(@D)/.config) endif $(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) oldconfig $(Q)touch $@ @@ -127,6 +140,23 @@ linux26: host-module-init-tools $(LINUX26_DEPENDENCIES) $(LINUX26_DIR)/.stamp_in linux26-menuconfig linux26-xconfig linux26-gconfig: $(LINUX26_DIR)/.stamp_configured $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(LINUX26_DIR) $(subst linux26-,,$@) +# Support for rebuilding the kernel after the initramfs file list has +# been generated in $(BINARIES_DIR)/rootfs.initramfs. +$(LINUX26_DIR)/.stamp_initramfs_rebuilt: $(LINUX26_DIR)/.stamp_installed $(BINARIES_DIR)/rootfs.initramfs + @$(call MESSAGE,"Rebuilding kernel with initramfs") + # Remove the previously generated initramfs which was empty, + # to make sure the kernel will actually regenerate it. + $(RM) -f $(@D)/usr/initramfs_data.cpio.* + # Build the kernel. + $(TARGET_MAKE_ENV) $(MAKE) $(LINUX26_MAKE_FLAGS) -C $(@D) $(LINUX26_IMAGE_NAME) + # Copy the kernel image to its final destination + cp $(LINUX26_IMAGE_PATH) $(BINARIES_DIR) + $(Q)touch $@ + +# The initramfs building code must make sure this target gets called +# after it generated the initramfs list of files. +linux26-rebuild-with-initramfs: $(LINUX26_DIR)/.stamp_initramfs_rebuilt + ifeq ($(BR2_LINUX_KERNEL),y) TARGETS+=linux26 endif -- cgit v1.2.3