[PATCH V8 2/4] kbuild: Add generic rule to apply fdtoverlay

From: Viresh Kumar
Date: Fri Feb 12 2021 - 06:21:20 EST


From: Rob Herring <robh@xxxxxxxxxx>

Add a generic rule to apply fdtoverlay in Makefile.lib, so every
platform doesn't need to carry the complex rule.

The platform's Makefile only needs to have this now:

DTC_FLAGS_foo_base += -@
foo-dtbs := foo_base.dtb foo_overlay1.dtbo foo_overlay2.dtbo
dtb-y := foo.dtb

We don't want to run schema checks on foo.dtb (as foo.dts doesn't exist)
and the Makefile is updated accordingly.

Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
Co-developed-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
scripts/Makefile.lib | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index fa0db696120f..3c450bfec015 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -66,6 +66,10 @@ multi-used := $(multi-used-y) $(multi-used-m)
real-obj-y := $(foreach m, $(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m)))
real-obj-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)) $($(m:.o=-))),$($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)),$(m)))

+# List all dtbs to be generated by fdtoverlay
+overlay-y := $(foreach m,$(dtb-y), $(if $(strip $($(m:.dtb=-dtbs))),$(m),))
+overlay-$(CONFIG_OF_ALL_DTBS) += $(foreach m,$(dtb-), $(if $(strip $($(m:.dtb=-dtbs))),$(m),))
+
always-y += $(always-m)

# hostprogs-always-y += foo
@@ -80,14 +84,21 @@ userprogs += $(userprogs-always-y) $(userprogs-always-m)
always-y += $(userprogs-always-y) $(userprogs-always-m)

# DTB
+# Add base dtb and overlay dtbo
+dtb-y += $(foreach m,$(overlay-y), $($(m:.dtb=-dtbs)))
+
# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
dtb-$(CONFIG_OF_ALL_DTBS) += $(dtb-)

extra-y += $(dtb-y)

ifneq ($(CHECK_DTBS),)
-extra-y += $(patsubst %.dtb,%.dt.yaml, $(dtb-y))
-extra-y += $(patsubst %.dtbo,%.dt.yaml, $(dtb-y))
+# Don't run schema checks for dtbs created by fdtoverlay as they don't
+# have corresponding dts files.
+dt-yaml-y := $(filter-out $(overlay-y),$(dtb-y))
+
+extra-y += $(patsubst %.dtb,%.dt.yaml, $(dt-yaml-y))
+extra-y += $(patsubst %.dtbo,%.dt.yaml, $(dt-yaml-y))
endif

# Add subdir path
@@ -331,6 +342,15 @@ $(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
$(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE
$(call if_changed_dep,dtc)

+overlay-y := $(addprefix $(obj)/, $(overlay-y))
+
+quiet_cmd_fdtoverlay = DTOVL $@
+ cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(real-prereqs)
+
+$(overlay-y): FORCE
+ $(call if_changed,fdtoverlay)
+$(call multi_depend, $(overlay-y), .dtb, -dtbs)
+
DT_CHECKER ?= dt-validate
DT_BINDING_DIR := Documentation/devicetree/bindings
# DT_TMP_SCHEMA may be overridden from Documentation/devicetree/bindings/Makefile
--
2.25.0.rc1.19.g042ed3e048af