U-Boot always needs some sort of a device tree. Some boards never actually use this, at least in production systems, since a prior firmware stage sets one up and passes it to U-Boot. At present the only mechanism to do that is with custom function (OF_BOARD), but future work will include a standard way of doing this ('standard passage').
It can be confusing to see a device tree emitted from the U-Boot build in this situation. Add an option to drop it.
Signed-off-by: Simon Glass sjg@chromium.org ---
(no changes since v1)
Makefile | 6 +++++- dts/Kconfig | 10 ++++++++++ 2 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/Makefile b/Makefile index 6671c5d9e2f..a3f018f01e0 100644 --- a/Makefile +++ b/Makefile @@ -952,7 +952,11 @@ INPUTS-$(CONFIG_SPL_FRAMEWORK) += u-boot.img endif endif INPUTS-$(CONFIG_TPL) += tpl/u-boot-tpl.bin + +# Allow omitting the .dtb output if it is not normally used +ifndef CONFIG_OF_OMIT_DTB INPUTS-$(CONFIG_OF_SEPARATE) += u-boot.dtb +endif ifeq ($(CONFIG_SPL_FRAMEWORK),y) INPUTS-$(CONFIG_OF_SEPARATE) += u-boot-dtb.img endif @@ -1192,7 +1196,7 @@ u-boot.bin: u-boot-fit-dtb.bin FORCE u-boot-dtb.bin: u-boot-nodtb.bin dts/dt.dtb FORCE $(call if_changed,cat)
-else ifeq ($(CONFIG_OF_SEPARATE),y) +else ifeq ($(CONFIG_OF_SEPARATE).$(CONFIG_OF_OMIT_DTB),y.) u-boot-dtb.bin: u-boot-nodtb.bin dts/dt.dtb FORCE $(call if_changed,cat)
diff --git a/dts/Kconfig b/dts/Kconfig index 803d0899556..fd2829ad708 100644 --- a/dts/Kconfig +++ b/dts/Kconfig @@ -129,6 +129,16 @@ config OF_HAS_PRIOR_STAGE Note: This option must be set in Kconfig and cannot be enabled or disabled in the board's defconfig file.
+config OF_OMIT_DTB + bool "Omit the device tree output when building" + default y if OF_HAS_PRIOR_STAGE && !BINMAN + help + As a special case, avoid writing a device tree file u-boot.dtb when + building. Also don't include that file in u-boot.bin + + This is used for boards which normally provide a devicetree via a + runtime mechanism (such as OF_BOARD), to avoid confusion. + config DEFAULT_DEVICE_TREE string "Default Device Tree for DT control" depends on OF_CONTROL