buildroot/linux/linux.mk
Thomas De Schampheleire 00daf37c4f linux: avoid unnecessary changes in defconfig for INITRAMFS_SOURCE
When Buildroot is configured to append the root filesystem to the Linux
kernel as initramfs, Buildroot sets the path to the initramfs source
dynamically in the Linux configuration file.

As this path is specified as an absolute path, typically being different
for different users of the same project (e.g. containing a username),
saving the configuration to a version control system (for example using
'make linux-update-defconfig') would result in a difference for this
path at every invocation by a different user.
Although this is technically not an issue, it is confusing that this
generates a difference.

Address this issue by using a not-yet-expanded make variable to specify
the path to the initramfs source. That variable will be expanded by the
Linux build system, which uses it both as a Makefile variable and a
shell variable; thus, it needs to be specified in LINUX_MAKE_ENV (so
it is exported and available in sub-processes of make).  Any saved
configuration file would simply contain the reference to the
not-yet-expanded variable.

As in the Linux build system, the config variables are both read from
make as from a shell script, we cannot use $() syntax as this would be
interpreted as a command invocation by the shell. Instead, use ${}
syntax which is interpreted as variable reference both by the shell as
by make.

[Thomas:
 - Really make the patch work by using $(LINUX_MAKE_ENV) instead of
   $(TARGET_MAKE_ENV). Otherwise, the new BR2_BINARIES_DIR variable is
   not passed at all stages of the build process, which makes the
   build fail when an initramfs is used.]

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Signed-off-by: "Yann E. Morin" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2015-02-14 17:31:03 +01:00

360 lines
13 KiB
Makefile

################################################################################
#
# Linux kernel target
#
################################################################################
LINUX_VERSION = $(call qstrip,$(BR2_LINUX_KERNEL_VERSION))
LINUX_LICENSE = GPLv2
LINUX_LICENSE_FILES = COPYING
# Compute LINUX_SOURCE and LINUX_SITE from the configuration
ifeq ($(BR2_LINUX_KERNEL_CUSTOM_TARBALL),y)
LINUX_TARBALL = $(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_TARBALL_LOCATION))
LINUX_SITE = $(patsubst %/,%,$(dir $(LINUX_TARBALL)))
LINUX_SOURCE = $(notdir $(LINUX_TARBALL))
else ifeq ($(BR2_LINUX_KERNEL_CUSTOM_LOCAL),y)
LINUX_SITE = $(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_LOCAL_PATH))
LINUX_SITE_METHOD = local
else ifeq ($(BR2_LINUX_KERNEL_CUSTOM_GIT),y)
LINUX_SITE = $(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_REPO_URL))
LINUX_SITE_METHOD = git
else ifeq ($(BR2_LINUX_KERNEL_CUSTOM_HG),y)
LINUX_SITE = $(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_REPO_URL))
LINUX_SITE_METHOD = hg
else
LINUX_SOURCE = linux-$(LINUX_VERSION).tar.xz
# In X.Y.Z, get X and Y. We replace dots and dashes by spaces in order
# to use the $(word) function. We support versions such as 3.1,
# 2.6.32, 2.6.32-rc1, 3.0-rc6, etc.
ifeq ($(findstring x2.6.,x$(LINUX_VERSION)),x2.6.)
LINUX_SITE = $(BR2_KERNEL_MIRROR)/linux/kernel/v2.6
else
LINUX_SITE = $(BR2_KERNEL_MIRROR)/linux/kernel/v3.x
endif
# release candidates are in testing/ subdir
ifneq ($(findstring -rc,$(LINUX_VERSION)),)
LINUX_SITE := $(LINUX_SITE)/testing/
endif # -rc
endif
LINUX_PATCHES = $(call qstrip,$(BR2_LINUX_KERNEL_PATCH))
LINUX_INSTALL_IMAGES = YES
LINUX_DEPENDENCIES += host-kmod host-lzop
ifeq ($(BR2_LINUX_KERNEL_UBOOT_IMAGE),y)
LINUX_DEPENDENCIES += host-uboot-tools
endif
LINUX_MAKE_FLAGS = \
HOSTCC="$(HOSTCC)" \
HOSTCFLAGS="$(HOSTCFLAGS)" \
ARCH=$(KERNEL_ARCH) \
INSTALL_MOD_PATH=$(TARGET_DIR) \
CROSS_COMPILE="$(CCACHE) $(TARGET_CROSS)" \
DEPMOD=$(HOST_DIR)/sbin/depmod
LINUX_MAKE_ENV = \
$(TARGET_MAKE_ENV) \
BR_BINARIES_DIR=$(BINARIES_DIR)
# Get the real Linux version, which tells us where kernel modules are
# going to be installed in the target filesystem.
LINUX_VERSION_PROBED = $(shell $(MAKE) $(LINUX_MAKE_FLAGS) -C $(LINUX_DIR) --no-print-directory -s kernelrelease)
ifeq ($(BR2_LINUX_KERNEL_USE_INTREE_DTS),y)
KERNEL_DTS_NAME = $(call qstrip,$(BR2_LINUX_KERNEL_INTREE_DTS_NAME))
else ifeq ($(BR2_LINUX_KERNEL_USE_CUSTOM_DTS),y)
KERNEL_DTS_NAME = $(basename $(notdir $(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_DTS_PATH))))
endif
ifeq ($(BR2_LINUX_KERNEL_DTS_SUPPORT)$(KERNEL_DTS_NAME),y)
$(error No kernel device tree source specified, check your \
BR2_LINUX_KERNEL_USE_INTREE_DTS / BR2_LINUX_KERNEL_USE_CUSTOM_DTS settings)
endif
ifeq ($(BR2_LINUX_KERNEL_APPENDED_DTB),y)
ifneq ($(words $(KERNEL_DTS_NAME)),1)
$(error Kernel with appended device tree needs exactly one DTS source. \
Check BR2_LINUX_KERNEL_INTREE_DTS_NAME or BR2_LINUX_KERNEL_CUSTOM_DTS_PATH.)
endif
endif
KERNEL_DTBS = $(addsuffix .dtb,$(KERNEL_DTS_NAME))
ifeq ($(BR2_LINUX_KERNEL_IMAGE_TARGET_CUSTOM),y)
LINUX_IMAGE_NAME = $(call qstrip,$(BR2_LINUX_KERNEL_IMAGE_NAME))
LINUX_TARGET_NAME = $(call qstrip,$(BR2_LINUX_KERNEL_IMAGE_TARGET_NAME))
ifeq ($(LINUX_IMAGE_NAME),)
LINUX_IMAGE_NAME = $(LINUX_TARGET_NAME)
endif
else
ifeq ($(BR2_LINUX_KERNEL_UIMAGE),y)
LINUX_IMAGE_NAME = uImage
else ifeq ($(BR2_LINUX_KERNEL_APPENDED_UIMAGE),y)
LINUX_IMAGE_NAME = uImage
else ifeq ($(BR2_LINUX_KERNEL_BZIMAGE),y)
LINUX_IMAGE_NAME = bzImage
else ifeq ($(BR2_LINUX_KERNEL_ZIMAGE),y)
LINUX_IMAGE_NAME = zImage
else ifeq ($(BR2_LINUX_KERNEL_APPENDED_ZIMAGE),y)
LINUX_IMAGE_NAME = zImage
else ifeq ($(BR2_LINUX_KERNEL_CUIMAGE),y)
LINUX_IMAGE_NAME = cuImage.$(KERNEL_DTS_NAME)
else ifeq ($(BR2_LINUX_KERNEL_SIMPLEIMAGE),y)
LINUX_IMAGE_NAME = simpleImage.$(KERNEL_DTS_NAME)
else ifeq ($(BR2_LINUX_KERNEL_LINUX_BIN),y)
LINUX_IMAGE_NAME = linux.bin
else ifeq ($(BR2_LINUX_KERNEL_VMLINUX_BIN),y)
LINUX_IMAGE_NAME = vmlinux.bin
else ifeq ($(BR2_LINUX_KERNEL_VMLINUX),y)
LINUX_IMAGE_NAME = vmlinux
else ifeq ($(BR2_LINUX_KERNEL_VMLINUZ),y)
LINUX_IMAGE_NAME = vmlinuz
endif
# The if-else blocks above are all the image types we know of, and all
# come from a Kconfig choice, so we know we have LINUX_IMAGE_NAME set
# to something
LINUX_TARGET_NAME = $(LINUX_IMAGE_NAME)
endif
LINUX_KERNEL_UIMAGE_LOADADDR = $(call qstrip,$(BR2_LINUX_KERNEL_UIMAGE_LOADADDR))
ifneq ($(LINUX_KERNEL_UIMAGE_LOADADDR),)
LINUX_MAKE_FLAGS += LOADADDR="$(LINUX_KERNEL_UIMAGE_LOADADDR)"
endif
# Compute the arch path, since i386 and x86_64 are in arch/x86 and not
# in arch/$(KERNEL_ARCH). Even if the kernel creates symbolic links
# for bzImage, arch/i386 and arch/x86_64 do not exist when copying the
# defconfig file.
ifeq ($(KERNEL_ARCH),i386)
KERNEL_ARCH_PATH = $(LINUX_DIR)/arch/x86
else ifeq ($(KERNEL_ARCH),x86_64)
KERNEL_ARCH_PATH = $(LINUX_DIR)/arch/x86
else
KERNEL_ARCH_PATH = $(LINUX_DIR)/arch/$(KERNEL_ARCH)
endif
ifeq ($(BR2_LINUX_KERNEL_VMLINUX),y)
LINUX_IMAGE_PATH = $(LINUX_DIR)/$(LINUX_IMAGE_NAME)
else ifeq ($(BR2_LINUX_KERNEL_VMLINUZ),y)
LINUX_IMAGE_PATH = $(LINUX_DIR)/$(LINUX_IMAGE_NAME)
else
ifeq ($(KERNEL_ARCH),avr32)
LINUX_IMAGE_PATH = $(KERNEL_ARCH_PATH)/boot/images/$(LINUX_IMAGE_NAME)
else
LINUX_IMAGE_PATH = $(KERNEL_ARCH_PATH)/boot/$(LINUX_IMAGE_NAME)
endif
endif # BR2_LINUX_KERNEL_VMLINUX
define LINUX_DOWNLOAD_PATCHES
$(if $(LINUX_PATCHES),
@$(call MESSAGE,"Download additional patches"))
$(foreach patch,$(filter ftp://% http://% https://%,$(LINUX_PATCHES)),\
$(call DOWNLOAD_WGET,$(patch),$(notdir $(patch)))$(sep))
endef
LINUX_POST_DOWNLOAD_HOOKS += LINUX_DOWNLOAD_PATCHES
define LINUX_APPLY_PATCHES
for p in $(LINUX_PATCHES) ; do \
if echo $$p | grep -q -E "^ftp://|^http://|^https://" ; then \
$(APPLY_PATCHES) $(@D) $(DL_DIR) `basename $$p` ; \
elif test -d $$p ; then \
$(APPLY_PATCHES) $(@D) $$p linux-\*.patch ; \
else \
$(APPLY_PATCHES) $(@D) `dirname $$p` `basename $$p` ; \
fi \
done
endef
LINUX_POST_PATCH_HOOKS += LINUX_APPLY_PATCHES
ifeq ($(BR2_LINUX_KERNEL_USE_DEFCONFIG),y)
KERNEL_SOURCE_CONFIG = $(KERNEL_ARCH_PATH)/configs/$(call qstrip,$(BR2_LINUX_KERNEL_DEFCONFIG))_defconfig
else ifeq ($(BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG),y)
KERNEL_SOURCE_CONFIG = $(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE))
endif
LINUX_KCONFIG_FILE = $(KERNEL_SOURCE_CONFIG)
LINUX_KCONFIG_EDITORS = menuconfig xconfig gconfig nconfig
LINUX_KCONFIG_OPTS = $(LINUX_MAKE_FLAGS)
define LINUX_KCONFIG_FIXUP_CMDS
$(if $(BR2_arm)$(BR2_armeb),
$(call KCONFIG_ENABLE_OPT,CONFIG_AEABI,$(@D)/.config))
$(if $(BR2_TARGET_ROOTFS_CPIO),
$(call KCONFIG_ENABLE_OPT,CONFIG_BLK_DEV_INITRD,$(@D)/.config))
# As the kernel gets compiled before root filesystems are
# built, we create a fake cpio file. It'll be
# replaced later by the real cpio archive, and the kernel will be
# rebuilt using the linux-rebuild-with-initramfs target.
$(if $(BR2_TARGET_ROOTFS_INITRAMFS),
touch $(BINARIES_DIR)/rootfs.cpio
$(call KCONFIG_SET_OPT,CONFIG_INITRAMFS_SOURCE,"$${BR_BINARIES_DIR}/rootfs.cpio",$(@D)/.config)
$(call KCONFIG_SET_OPT,CONFIG_INITRAMFS_ROOT_UID,0,$(@D)/.config)
$(call KCONFIG_SET_OPT,CONFIG_INITRAMFS_ROOT_GID,0,$(@D)/.config))
$(if $(BR2_ROOTFS_DEVICE_CREATION_STATIC),,
$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS_MOUNT,$(@D)/.config))
$(if $(BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_EUDEV),
$(call KCONFIG_ENABLE_OPT,CONFIG_INOTIFY_USER,$(@D)/.config))
$(if $(BR2_PACKAGE_KTAP),
$(call KCONFIG_ENABLE_OPT,CONFIG_DEBUG_FS,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_EVENT_TRACING,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_PERF_EVENTS,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_FUNCTION_TRACER,$(@D)/.config))
$(if $(BR2_PACKAGE_SYSTEMD),
$(call KCONFIG_ENABLE_OPT,CONFIG_CGROUPS,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_INOTIFY_USER,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_FHANDLE,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_AUTOFS4_FS,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_TMPFS_POSIX_ACL,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_TMPFS_POSIX_XATTR,$(@D)/.config))
$(if $(BR2_PACKAGE_SMACK),
$(call KCONFIG_ENABLE_OPT,CONFIG_SECURITY,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_SECURITY_SMACK,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_SECURITY_NETWORK,$(@D)/.config))
$(if $(BR2_PACKAGE_IPTABLES),
$(call KCONFIG_ENABLE_OPT,CONFIG_IP_NF_IPTABLES,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_IP_NF_FILTER,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_NETFILTER,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_NETFILTER_XTABLES,$(@D)/.config))
$(if $(BR2_PACKAGE_XTABLES_ADDONS),
$(call KCONFIG_ENABLE_OPT,CONFIG_NF_CONNTRACK,$(@D)/.config)
$(call KCONFIG_ENABLE_OPT,CONFIG_NF_CONNTRACK_MARK,$(@D)/.config))
$(if $(BR2_LINUX_KERNEL_APPENDED_DTB),
$(call KCONFIG_ENABLE_OPT,CONFIG_ARM_APPENDED_DTB,$(@D)/.config))
endef
ifeq ($(BR2_LINUX_KERNEL_DTS_SUPPORT),y)
ifeq ($(BR2_LINUX_KERNEL_DTB_IS_SELF_BUILT),)
define LINUX_BUILD_DTB
$(LINUX_MAKE_ENV) $(MAKE) $(LINUX_MAKE_FLAGS) -C $(@D) $(KERNEL_DTBS)
endef
define LINUX_INSTALL_DTB
# dtbs moved from arch/<ARCH>/boot to arch/<ARCH>/boot/dts since 3.8-rc1
cp $(addprefix \
$(KERNEL_ARCH_PATH)/boot/$(if $(wildcard \
$(addprefix $(KERNEL_ARCH_PATH)/boot/dts/,$(KERNEL_DTBS))),dts/),$(KERNEL_DTBS)) \
$(BINARIES_DIR)/
endef
define LINUX_INSTALL_DTB_TARGET
# dtbs moved from arch/<ARCH>/boot to arch/<ARCH>/boot/dts since 3.8-rc1
cp $(addprefix \
$(KERNEL_ARCH_PATH)/boot/$(if $(wildcard \
$(addprefix $(KERNEL_ARCH_PATH)/boot/dts/,$(KERNEL_DTBS))),dts/),$(KERNEL_DTBS)) \
$(TARGET_DIR)/boot/
endef
endif
endif
ifeq ($(BR2_LINUX_KERNEL_APPENDED_DTB),y)
# dtbs moved from arch/$ARCH/boot to arch/$ARCH/boot/dts since 3.8-rc1
define LINUX_APPEND_DTB
if [ -e $(KERNEL_ARCH_PATH)/boot/$(KERNEL_DTS_NAME).dtb ]; then \
cat $(KERNEL_ARCH_PATH)/boot/$(KERNEL_DTS_NAME).dtb; \
else \
cat $(KERNEL_ARCH_PATH)/boot/dts/$(KERNEL_DTS_NAME).dtb; \
fi >> $(KERNEL_ARCH_PATH)/boot/zImage
endef
ifeq ($(BR2_LINUX_KERNEL_APPENDED_UIMAGE),y)
# We need to generate a new u-boot image that takes into
# account the extra-size added by the device tree at the end
# of the image. To do so, we first need to retrieve both load
# address and entry point for the kernel from the already
# generate uboot image before using mkimage -l.
LINUX_APPEND_DTB += $(sep) MKIMAGE_ARGS=`$(MKIMAGE) -l $(LINUX_IMAGE_PATH) |\
sed -n -e 's/Image Name:[ ]*\(.*\)/-n \1/p' -e 's/Load Address:/-a/p' -e 's/Entry Point:/-e/p'`; \
$(MKIMAGE) -A $(MKIMAGE_ARCH) -O linux \
-T kernel -C none $${MKIMAGE_ARGS} \
-d $(KERNEL_ARCH_PATH)/boot/zImage $(LINUX_IMAGE_PATH);
endif
endif
# Compilation. We make sure the kernel gets rebuilt when the
# configuration has changed.
define LINUX_BUILD_CMDS
$(if $(BR2_LINUX_KERNEL_USE_CUSTOM_DTS),
cp $(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_DTS_PATH)) $(KERNEL_ARCH_PATH)/boot/dts/)
$(LINUX_MAKE_ENV) $(MAKE) $(LINUX_MAKE_FLAGS) -C $(@D) $(LINUX_TARGET_NAME)
@if grep -q "CONFIG_MODULES=y" $(@D)/.config; then \
$(LINUX_MAKE_ENV) $(MAKE) $(LINUX_MAKE_FLAGS) -C $(@D) modules ; \
fi
$(LINUX_BUILD_DTB)
$(LINUX_APPEND_DTB)
endef
ifeq ($(BR2_LINUX_KERNEL_INSTALL_TARGET),y)
define LINUX_INSTALL_KERNEL_IMAGE_TO_TARGET
install -m 0644 -D $(LINUX_IMAGE_PATH) $(TARGET_DIR)/boot/$(LINUX_IMAGE_NAME)
$(LINUX_INSTALL_DTB_TARGET)
endef
endif
define LINUX_INSTALL_HOST_TOOLS
# Installing dtc (device tree compiler) as host tool, if selected
if grep -q "CONFIG_DTC=y" $(@D)/.config; then \
$(INSTALL) -D -m 0755 $(@D)/scripts/dtc/dtc $(HOST_DIR)/usr/bin/dtc ; \
fi
endef
define LINUX_INSTALL_IMAGES_CMDS
cp $(LINUX_IMAGE_PATH) $(BINARIES_DIR)
$(LINUX_INSTALL_DTB)
endef
define LINUX_INSTALL_TARGET_CMDS
$(LINUX_INSTALL_KERNEL_IMAGE_TO_TARGET)
# Install modules and remove symbolic links pointing to build
# directories, not relevant on the target
@if grep -q "CONFIG_MODULES=y" $(@D)/.config; then \
$(LINUX_MAKE_ENV) $(MAKE1) $(LINUX_MAKE_FLAGS) -C $(@D) modules_install; \
rm -f $(TARGET_DIR)/lib/modules/$(LINUX_VERSION_PROBED)/build ; \
rm -f $(TARGET_DIR)/lib/modules/$(LINUX_VERSION_PROBED)/source ; \
fi
$(LINUX_INSTALL_HOST_TOOLS)
endef
include $(sort $(wildcard linux/linux-ext-*.mk))
$(eval $(kconfig-package))
# Support for rebuilding the kernel after the cpio archive has
# been generated in $(BINARIES_DIR)/rootfs.cpio.
$(LINUX_DIR)/.stamp_initramfs_rebuilt: $(LINUX_DIR)/.stamp_target_installed $(LINUX_DIR)/.stamp_images_installed $(BINARIES_DIR)/rootfs.cpio
@$(call MESSAGE,"Rebuilding kernel with initramfs")
# Build the kernel.
$(LINUX_MAKE_ENV) $(MAKE) $(LINUX_MAKE_FLAGS) -C $(@D) $(LINUX_TARGET_NAME)
$(LINUX_APPEND_DTB)
# Copy the kernel image to its final destination
cp $(LINUX_IMAGE_PATH) $(BINARIES_DIR)
# If there is a .ub file copy it to the final destination
test ! -f $(LINUX_IMAGE_PATH).ub || cp $(LINUX_IMAGE_PATH).ub $(BINARIES_DIR)
$(Q)touch $@
# The initramfs building code must make sure this target gets called
# after it generated the initramfs list of files.
linux-rebuild-with-initramfs: $(LINUX_DIR)/.stamp_initramfs_rebuilt
# Checks to give errors that the user can understand
ifeq ($(filter source,$(MAKECMDGOALS)),)
ifeq ($(BR2_LINUX_KERNEL_USE_DEFCONFIG),y)
ifeq ($(call qstrip,$(BR2_LINUX_KERNEL_DEFCONFIG)),)
$(error No kernel defconfig name specified, check your BR2_LINUX_KERNEL_DEFCONFIG setting)
endif
endif
ifeq ($(BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG),y)
ifeq ($(call qstrip,$(BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE)),)
$(error No kernel configuration file specified, check your BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE setting)
endif
endif
endif