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| author | Michael Tretter <m.tretter@pengutronix.de> | 2019-09-13 15:14:46 +0200 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2019-09-16 09:06:45 +0200 |
| commit | 27112f5b5541d736a560dbc9f059d879d4b354a3 (patch) | |
| tree | 6d8423c28fb3e163aa99d87c660a4ba98bbbabdf | |
| parent | 4d6ff095684d180221fd924e8ba13fcc77c8366a (diff) | |
| download | barebox-27112f5b5541d736a560dbc9f059d879d4b354a3.tar.gz barebox-27112f5b5541d736a560dbc9f059d879d4b354a3.tar.xz | |
dtc: optionally add add __symbols__ to build-in devicetree
The devicetree overlay driver requires the __symbols__ node to resolve
phandles to the base devicetree. If Barebox has to apply the overlay to
the live devicetree, the build-in devicetree must be built with the
__symbols__ node.
It is configurable, because adding __symbols__ significantly increases
the size of the devicetree binary. When configuring Barebox, a developer
should be able to enable or disable devicetree overlay support and as
this only affects the build-in devicetree, which is linked to the image
anyway, use a Kconfig item for configuring the __symbols__.
Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
| -rw-r--r-- | drivers/of/Kconfig | 16 | ||||
| -rw-r--r-- | scripts/Makefile.lib | 4 |
2 files changed, 20 insertions, 0 deletions
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig index 1bb6639c5a..7436fc2de1 100644 --- a/drivers/of/Kconfig +++ b/drivers/of/Kconfig @@ -59,3 +59,19 @@ config OF_OVERLAY not patch the live devicetree, but applies the overlays as fixup to the devicetree. Furthermore, overlays cannot be removed after they have been applied. + +config OF_OVERLAY_LIVE + depends on OF_OVERLAY + bool "Support devicetree overlays on live devicetree" + help + This option allows to use devicetree overlays with the live + devicetree. It is not required to apply overlays to any other + devicetree. + + This builds the build-in devicetree with __symbols__, which + significantly increases the size of the dtb file. + + Enable this option only if you actually need the live devicetree + while applying in the devicetree overlay. This is usually the case if + applying the overlay has other side effects than changing the + devicetree. diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index c4d307ae30..ad0484de3a 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -292,6 +292,10 @@ DTC_FLAGS += -Wno-unit_address_vs_reg \ -Wno-unique_unit_address \ -Wno-pci_device_reg +ifeq ($(CONFIG_OF_OVERLAY_LIVE), y) +DTC_FLAGS += -@ +endif + # Generate an assembly file to wrap the output of the device tree compiler quiet_cmd_dt_S_dtb = DTB $@ cmd_dt_S_dtb = $(srctree)/scripts/gen-dtb-s $(subst -,_,$(*F)) $< $(CONFIG_IMD) > $@ |