kernel: Allow to limit the used .dtb files for the final DTB image
On some devices too many .dtb files are generated. Instead of taking
all of them, allow to only take selected .dtb files for the final
DTB image.
Example: Motorola Edge 40 Pro (rtwo, sm8550) generates the following:
obj/DTB_OBJ/out/kaka-rumi.dtb
obj/DTB_OBJ/out/kalama-rtwo-base-kalama-rtwo-evb1-overlay.dtb
obj/DTB_OBJ/out/kalama-rtwo-base-kalama-rtwo-evt1-overlay.dtb
obj/DTB_OBJ/out/kalama-rtwo-base-kalama-rtwo-na-vzw-evt2-overlay.dtb
obj/DTB_OBJ/out/kalama-rtwo-base-kalama-rtwo-prc-dvt1b-overlay.dtb
obj/DTB_OBJ/out/kalama-rtwo-base-kalama-rtwo-prc-pvt-overlay.dtb
obj/DTB_OBJ/out/kalama-rtwo-base-kalama-rtwo-row-dvt1b-overlay.dtb
obj/DTB_OBJ/out/kalama-rtwo-base.dtb
obj/DTB_OBJ/out/kalama-v2-rtwo-base-kalama-rtwo-evb1-overlay.dtb
obj/DTB_OBJ/out/kalama-v2-rtwo-base-kalama-rtwo-evt1-overlay.dtb
obj/DTB_OBJ/out/kalama-v2-rtwo-base-kalama-rtwo-na-vzw-evt2-overlay.dtb
obj/DTB_OBJ/out/kalama-v2-rtwo-base-kalama-rtwo-prc-dvt1b-overlay.dtb
obj/DTB_OBJ/out/kalama-v2-rtwo-base-kalama-rtwo-prc-pvt-overlay.dtb
obj/DTB_OBJ/out/kalama-v2-rtwo-base-kalama-rtwo-row-dvt1b-overlay.dtb
obj/DTB_OBJ/out/kalama-v2-rtwo-base.dtb
with only kalama-rtwo-base.dtb and kalama-v2-rtwo-base.dtb needed.
Disabling compilation of the other kalama.dtb isn't possible, as this
would also disable the compilation of the needed .dtbo files.
Because they are earlier in alphabetical order, and the matching
board ids, the bootloader ends up selecting those, instead of the
correct ones. This results in USB (and possible other things) to
not work.
Change-Id: I486b6ec538a3e4906b5b8aa5ecb355b480b60de7
diff --git a/build/tasks/kernel.mk b/build/tasks/kernel.mk
index 0574c7c..2b2f7ef 100644
--- a/build/tasks/kernel.mk
+++ b/build/tasks/kernel.mk
@@ -67,6 +67,9 @@
#
# TARGET_FORCE_PREBUILT_KERNEL = Optional, use TARGET_PREBUILT_KERNEL even if
# kernel sources are present
+#
+# TARGET_MERGE_DTBS_WILDCARD = Optional, limits the .dtb files used to generate the
+# final DTB image when using QCOM's merge_dtbs script.
ifneq ($(TARGET_NO_KERNEL),true)
ifneq ($(TARGET_NO_KERNEL_OVERRIDE),true)
@@ -78,6 +81,8 @@
RECOVERY_DEFCONFIG := $(TARGET_KERNEL_RECOVERY_CONFIG)
VARIANT_DEFCONFIG := $(TARGET_KERNEL_VARIANT_CONFIG)
SELINUX_DEFCONFIG := $(TARGET_KERNEL_SELINUX_CONFIG)
+# dtb generation - optional
+TARGET_MERGE_DTBS_WILDCARD ?= *
## Internal variables
DTC := $(HOST_OUT_EXECUTABLES)/dtc
@@ -581,7 +586,7 @@
$(hide) find $(DTBS_OUT) -type f -name "*.dtb*" | xargs rm -f
mv $(DTB_OUT)/arch/$(KERNEL_ARCH)/boot/dts/vendor/qcom/*.dtb $(DTB_OUT)/arch/$(KERNEL_ARCH)/boot/dts/vendor/*/*.dtbo $(DTBS_BASE)/
PATH=$(abspath $(HOST_OUT_EXECUTABLES)):$${PATH} python3 $(BUILD_TOP)/vendor/lineage/build/tools/merge_dtbs.py $(DTBS_BASE) $(DTB_OUT)/arch/$(KERNEL_ARCH)/boot/dts/vendor/qcom $(DTBS_OUT)
- cat $(shell find $(DTB_OUT)/out -type f -name "*.dtb" | sort) > $@
+ cat $(shell find $(DTB_OUT)/out -type f -name "${TARGET_MERGE_DTBS_WILDCARD}.dtb" | sort) > $@
else
cat $(shell find $(DTB_OUT)/arch/$(KERNEL_ARCH)/boot/dts -type f -name "*.dtb" | sort) > $@
endif # BOARD_USES_QCOM_MERGE_DTBS_SCRIPT