[Buildroot] [PATCH 2/4] Add support for appended device tree blobs for arm
Thomas Petazzoni
thomas.petazzoni at free-electrons.com
Mon Jul 16 13:01:46 UTC 2012
Le Tue, 3 Jul 2012 12:01:14 +0200,
Maxime Ripard <maxime.ripard at free-electrons.com> a écrit :
> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
> ---
> linux/Config.in | 8 ++++++++
> linux/linux.mk | 38 +++++++++++++++++++++++++++++++++++++-
> 2 files changed, 45 insertions(+), 1 deletion(-)
>
> diff --git a/linux/Config.in b/linux/Config.in
> index 6f704b0..46b9756 100644
> --- a/linux/Config.in
> +++ b/linux/Config.in
> @@ -132,6 +132,14 @@ config BR2_LINUX_KERNEL_DTS_SUPPORT
>
> if BR2_LINUX_KERNEL_DTS_SUPPORT
>
> +config BR2_LINUX_KERNEL_APPENDED_DTB
> + bool "Append the Device Tree binary to the kernel"
Blob
> + depends on BR2_arm || BR2_armeb
> + help
> + After building the device tree blob, append it to the
> + kernel image. If necessary generates a uImage from that
> + new kernel image afterward.
This should rather be *after* the Device Tree Source choice and
selection, in my opinion. It would be more logical: (1) what I include,
(2) how I include it.
> choice
> prompt "Device tree source"
> default BR2_LINUX_KERNEL_USE_DEFAULT_DTS
> diff --git a/linux/linux.mk b/linux/linux.mk
> index 0540aeb..483974c 100644
> --- a/linux/linux.mk
> +++ b/linux/linux.mk
> @@ -52,6 +52,13 @@ else ifeq ($(BR2_LINUX_KERNEL_USE_CUSTOM_DTS),y)
> KERNEL_DTS_NAME = $(basename $(notdir $(BR2_LINUX_KERNEL_CUSTOM_DTS_FILE)))
> endif
>
> +ifeq ($(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_DTS_FILE or BR2_LINUX_KERNEL_CUSTOM_DTS_FILE.)
> +endif
> +endif
> +
> ifeq ($(BR2_LINUX_KERNEL_IMAGE_TARGET_CUSTOM),y)
> LINUX_IMAGE_NAME=$(call qstrip,$(BR2_LINUX_KERNEL_IMAGE_TARGET_NAME))
> else
> @@ -76,6 +83,12 @@ LINUX_IMAGE_NAME=vmlinuz
> endif
> endif
>
> +ifeq ($(BR2_LINUX_KERNEL_APPENDED_DTB),y)
> +LINUX_IMAGE_TARGET=zImage
> +else
> +LINUX_IMAGE_TARGET=$(LINUX_IMAGE_NAME)
> +endif
> +
> # Compute the arch path, since i386 and x86_64 are in arch/x86 and not
> # in arch/$(KERNEL_ARCH). Even if the kernel creates symbolic links
> # for bzImage, arch/i386 and arch/x86_64 do not exist when copying the
> @@ -155,6 +168,8 @@ define LINUX_CONFIGURE_CMDS
> $(call KCONFIG_SET_OPT,CONFIG_UEVENT_HELPER_PATH,\"/sbin/mdev\",$(@D)/.config))
> $(if $(BR2_PACKAGE_SYSTEMD),
> $(call KCONFIG_ENABLE_OPT,CONFIG_CGROUPS,$(@D)/.config))
> + $(if $(BR2_LINUX_KERNEL_APPENDED_DTB),
> + $(call KCONFIG_ENABLE_OPT,CONFIG_ARM_APPENDED_DTB,$(@D)/.config))
> yes '' | $(TARGET_MAKE_ENV) $(MAKE1) $(LINUX_MAKE_FLAGS) -C $(@D) oldconfig
> endef
>
> @@ -164,17 +179,38 @@ define LINUX_BUILD_DTB
> endef
> endif
>
> +ifeq ($(BR2_LINUX_KERNEL_APPENDED_DTB),y)
> +ifeq ($(BR2_LINUX_KERNEL_UBOOT_IMAGE),y)
> +define LINUX_APPEND_DTB
> + cat $(KERNEL_ARCH_PATH)/boot/zImage $(KERNEL_ARCH_PATH)/boot/$(KERNEL_DTS_NAME).dtb > $(KERNEL_ARCH_PATH)/boot/zImage_dtb
> + mv $(KERNEL_ARCH_PATH)/boot/zImage_dtb $(KERNEL_ARCH_PATH)/boot/zImage
> + LOAD=`$(MKIMAGE) -l $(LINUX_IMAGE_PATH) | sed -n 's/Load Address: \([0-9]*\)/\1/p'`; \
> + ENTRY=`$(MKIMAGE) -l $(LINUX_IMAGE_PATH) | sed -n 's/Entry Point: \([0-9]*\)/\1/p'`; \
> + $(MKIMAGE) -A $(KERNEL_ARCH) -O linux -T kernel -C none -a $${LOAD} -e $${ENTRY} -n 'Linux Buildroot' \
> + -d $(KERNEL_ARCH_PATH)/boot/zImage $(KERNEL_ARCH_PATH)/boot/$(LINUX_IMAGE_NAME)
> +endef
> +else ifeq ($(BR2_LINUX_KERNEL_ZIMAGE),y)
> +define LINUX_APPEND_DTB
> + cat $(KERNEL_ARCH_PATH)/boot/zImage $(KERNEL_ARCH_PATH)/boot/$(KERNEL_DTS_NAME).dtb > $(KERNEL_ARCH_PATH)/boot/zImage_dtb
> + mv $(KERNEL_ARCH_PATH)/boot/zImage_dtb $(KERNEL_ARCH_PATH)/boot/zImage
> +endef
> +else
> +$(error Appending DTB to the kernel image is only possible for u-boot images and zImage.)
Can't this be verified at the Kconfig level instead.
> +endif
> +endif
A big comment on top of this mkimage magic would be necessary.
Thomas
--
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com
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