| # Copyright (C) 2018-2024 The LineageOS Project |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| # |
| # |
| # Kernel build configuration variables |
| # ==================================== |
| # |
| # These config vars are usually set in BoardConfig.mk: |
| # |
| # TARGET_KERNEL_SOURCE = Kernel source dir, optional, defaults |
| # to kernel/$(TARGET_DEVICE_DIR) |
| # TARGET_KERNEL_ARCH = Kernel Arch |
| # TARGET_KERNEL_CROSS_COMPILE_PREFIX = Compiler prefix (e.g. arm-eabi-) |
| # defaults to arm-linux-androidkernel- for arm |
| # aarch64-linux-android- for arm64 |
| # x86_64-linux-android- for x86 |
| # |
| # TARGET_KERNEL_CLANG_COMPILE = Compile kernel with clang, defaults to true |
| # TARGET_KERNEL_CLANG_VERSION = Clang prebuilts version, optional, defaults to clang-stable |
| # TARGET_KERNEL_CLANG_PATH = Clang prebuilts path, optional |
| # |
| # TARGET_KERNEL_LLVM_BINUTILS = Use LLVM binutils, defaults to true |
| # TARGET_KERNEL_NO_GCC = Fully compile the kernel without GCC. |
| # Defaults to false |
| # TARGET_KERNEL_VERSION = Reported kernel version in top level kernel |
| # makefile. Can be overriden in device trees |
| # in the event of prebuilt kernel. |
| # |
| # TARGET_KERNEL_DTBO_PREFIX = Override path prefix of TARGET_KERNEL_DTBO. |
| # Defaults to empty |
| # TARGET_KERNEL_DTBO = Name of the kernel Makefile target that |
| # generates dtbo.img. Defaults to dtbo.img |
| # TARGET_KERNEL_DTB = Name of the kernel Makefile target that |
| # generates the *.dtb targets. Defaults to dtbs |
| # |
| # TARGET_KERNEL_EXT_MODULE_ROOT = Optional, the external modules root directory |
| # Defaults to empty |
| # TARGET_KERNEL_EXT_MODULES = Optional, the external modules we are |
| # building. Defaults to empty |
| # |
| # KERNEL_TOOLCHAIN_PREFIX = Overrides TARGET_KERNEL_CROSS_COMPILE_PREFIX, |
| # Set this var in shell to override |
| # toolchain specified in BoardConfig.mk |
| # KERNEL_TOOLCHAIN = Path to toolchain, if unset, assumes |
| # TARGET_KERNEL_CROSS_COMPILE_PREFIX |
| # is in PATH |
| # USE_CCACHE = Enable ccache (global Android flag) |
| |
| BUILD_TOP := $(abspath .) |
| |
| TARGET_AUTO_KDIR := $(shell echo $(TARGET_DEVICE_DIR) | sed -e 's/^device/kernel/g') |
| TARGET_KERNEL_SOURCE ?= $(TARGET_AUTO_KDIR) |
| |
| TARGET_KERNEL_ARCH := $(strip $(TARGET_KERNEL_ARCH)) |
| ifeq ($(TARGET_KERNEL_ARCH),) |
| KERNEL_ARCH := $(TARGET_ARCH) |
| else |
| KERNEL_ARCH := $(TARGET_KERNEL_ARCH) |
| endif |
| |
| KERNEL_VERSION := $(shell grep -s "^VERSION = " $(TARGET_KERNEL_SOURCE)/Makefile | awk '{ print $$3 }') |
| KERNEL_PATCHLEVEL := $(shell grep -s "^PATCHLEVEL = " $(TARGET_KERNEL_SOURCE)/Makefile | awk '{ print $$3 }') |
| TARGET_KERNEL_VERSION ?= $(shell echo $(KERNEL_VERSION)"."$(KERNEL_PATCHLEVEL)) |
| |
| # 5.10+ can fully compile without GCC by default |
| ifneq ($(KERNEL_VERSION),) |
| ifeq ($(shell expr $(KERNEL_VERSION) \>= 6), 1) |
| TARGET_KERNEL_NO_GCC ?= true |
| else ifeq ($(shell expr $(KERNEL_VERSION) \>= 5), 1) |
| ifeq ($(shell expr $(KERNEL_PATCHLEVEL) \>= 10), 1) |
| TARGET_KERNEL_NO_GCC ?= true |
| endif |
| endif |
| endif |
| |
| ifeq ($(TARGET_KERNEL_NO_GCC), true) |
| KERNEL_NO_GCC := true |
| endif |
| |
| LATEST_CLANG_VERSION ?= $(shell find $(BUILD_TOP)/prebuilts/clang/host/$(HOST_PREBUILT_TAG)/clang-*[0-9]* -maxdepth 0 | tr '-' '\n' | tail -n1) |
| ifneq ($(TARGET_KERNEL_CLANG_VERSION),) |
| KERNEL_CLANG_VERSION := clang-$(TARGET_KERNEL_CLANG_VERSION) |
| else |
| # Use the default version of clang if TARGET_KERNEL_CLANG_VERSION hasn't been set by the device config |
| KERNEL_CLANG_VERSION := clang-$(LATEST_CLANG_VERSION) |
| endif |
| TARGET_KERNEL_CLANG_PATH ?= $(BUILD_TOP)/prebuilts/clang/host/$(HOST_PREBUILT_TAG)/$(KERNEL_CLANG_VERSION) |
| |
| ifneq ($(USE_CCACHE),) |
| ifneq ($(CCACHE_EXEC),) |
| # Android 10+ deprecates use of a build ccache. Only system installed ones are now allowed |
| CCACHE_BIN := $(CCACHE_EXEC) |
| endif |
| endif |
| |
| # Clear this first to prevent accidental poisoning from env |
| KERNEL_MAKE_FLAGS := |
| |
| # Add back threads, ninja cuts this to $(getconf _NPROCESSORS_ONLN)/2 |
| KERNEL_MAKE_FLAGS += -j$(shell getconf _NPROCESSORS_ONLN) |
| |
| TOOLS_PATH_OVERRIDE := \ |
| PERL5LIB=$(BUILD_TOP)/prebuilts/tools-lineage/common/perl-base |
| |
| ifneq ($(KERNEL_NO_GCC), true) |
| GCC_PREBUILTS := $(BUILD_TOP)/prebuilts/gcc/$(HOST_PREBUILT_TAG) |
| # arm64 toolchain |
| KERNEL_TOOLCHAIN_arm64 := $(GCC_PREBUILTS)/aarch64/aarch64-linux-android-4.9/bin |
| KERNEL_TOOLCHAIN_PREFIX_arm64 := aarch64-linux-android- |
| # arm toolchain |
| KERNEL_TOOLCHAIN_arm := $(GCC_PREBUILTS)/arm/arm-linux-androideabi-4.9/bin |
| KERNEL_TOOLCHAIN_PREFIX_arm := arm-linux-androidkernel- |
| # x86 toolchain |
| KERNEL_TOOLCHAIN_x86 := $(GCC_PREBUILTS)/x86/x86_64-linux-android-4.9/bin |
| KERNEL_TOOLCHAIN_PREFIX_x86 := x86_64-linux-android- |
| |
| TARGET_KERNEL_CROSS_COMPILE_PREFIX := $(strip $(TARGET_KERNEL_CROSS_COMPILE_PREFIX)) |
| ifneq ($(TARGET_KERNEL_CROSS_COMPILE_PREFIX),) |
| KERNEL_TOOLCHAIN_PREFIX ?= $(TARGET_KERNEL_CROSS_COMPILE_PREFIX) |
| else |
| KERNEL_TOOLCHAIN ?= $(KERNEL_TOOLCHAIN_$(KERNEL_ARCH)) |
| KERNEL_TOOLCHAIN_PREFIX ?= $(KERNEL_TOOLCHAIN_PREFIX_$(KERNEL_ARCH)) |
| endif |
| |
| ifeq ($(KERNEL_TOOLCHAIN),) |
| KERNEL_TOOLCHAIN_PATH := $(KERNEL_TOOLCHAIN_PREFIX) |
| else |
| KERNEL_TOOLCHAIN_PATH := $(KERNEL_TOOLCHAIN)/$(KERNEL_TOOLCHAIN_PREFIX) |
| endif |
| |
| # We need to add GCC toolchain to the path no matter what |
| # for tools like `as` |
| KERNEL_TOOLCHAIN_PATH_gcc := $(KERNEL_TOOLCHAIN_$(KERNEL_ARCH)) |
| |
| ifneq ($(TARGET_KERNEL_CLANG_COMPILE),false) |
| KERNEL_CROSS_COMPILE := CROSS_COMPILE="$(KERNEL_TOOLCHAIN_PATH)" |
| else |
| KERNEL_CROSS_COMPILE := CROSS_COMPILE="$(CCACHE_BIN) $(KERNEL_TOOLCHAIN_PATH)" |
| endif |
| |
| # Needed for CONFIG_COMPAT_VDSO, safe to set for all arm64 builds |
| ifeq ($(KERNEL_ARCH),arm64) |
| KERNEL_CROSS_COMPILE += CROSS_COMPILE_ARM32="$(KERNEL_TOOLCHAIN_arm)/$(KERNEL_TOOLCHAIN_PREFIX_arm)" |
| KERNEL_CROSS_COMPILE += CROSS_COMPILE_COMPAT="$(KERNEL_TOOLCHAIN_arm)/$(KERNEL_TOOLCHAIN_PREFIX_arm)" |
| endif |
| |
| ifeq ($(TARGET_KERNEL_CLANG_COMPILE),false) |
| ifeq ($(KERNEL_ARCH),arm) |
| # Avoid "Unknown symbol _GLOBAL_OFFSET_TABLE_" errors |
| KERNEL_MAKE_FLAGS += CFLAGS_MODULE="-fno-pic" |
| endif |
| |
| ifeq ($(KERNEL_ARCH),arm64) |
| # Avoid "unsupported RELA relocation: 311" errors (R_AARCH64_ADR_GOT_PAGE) |
| KERNEL_MAKE_FLAGS += CFLAGS_MODULE="-fno-pic" |
| endif |
| endif |
| |
| KERNEL_MAKE_FLAGS += CPATH="/usr/include:/usr/include/x86_64-linux-gnu" HOSTLDFLAGS="-L/usr/lib/x86_64-linux-gnu -L/usr/lib64 -fuse-ld=lld" |
| |
| ifeq ($(KERNEL_ARCH),arm64) |
| # Add 32-bit GCC to PATH so that arm-linux-androidkernel-as is available for CONFIG_COMPAT_VDSO |
| TOOLS_PATH_OVERRIDE += PATH=$(BUILD_TOP)/prebuilts/tools-lineage/$(HOST_PREBUILT_TAG)/bin:$(KERNEL_TOOLCHAIN_arm):$$PATH |
| else |
| TOOLS_PATH_OVERRIDE += PATH=$(BUILD_TOP)/prebuilts/tools-lineage/$(HOST_PREBUILT_TAG)/bin:$$PATH |
| endif |
| |
| # Set the full path to the clang command and LLVM binutils |
| KERNEL_MAKE_FLAGS += HOSTCC=$(TARGET_KERNEL_CLANG_PATH)/bin/clang |
| KERNEL_MAKE_FLAGS += HOSTCXX=$(TARGET_KERNEL_CLANG_PATH)/bin/clang++ |
| ifneq ($(TARGET_KERNEL_CLANG_COMPILE), false) |
| ifneq ($(TARGET_KERNEL_LLVM_BINUTILS), false) |
| KERNEL_MAKE_FLAGS += LD=$(TARGET_KERNEL_CLANG_PATH)/bin/ld.lld |
| KERNEL_MAKE_FLAGS += AR=$(TARGET_KERNEL_CLANG_PATH)/bin/llvm-ar |
| endif |
| endif |
| else |
| KERNEL_MAKE_FLAGS += HOSTCFLAGS="--sysroot=$(BUILD_TOP)/prebuilts/gcc/linux-x86/host/x86_64-linux-glibc2.17-4.8/sysroot -I$(BUILD_TOP)/prebuilts/kernel-build-tools/linux-x86/include" |
| KERNEL_MAKE_FLAGS += HOSTLDFLAGS="--sysroot=$(BUILD_TOP)/prebuilts/gcc/linux-x86/host/x86_64-linux-glibc2.17-4.8/sysroot -Wl,-rpath,$(BUILD_TOP)/prebuilts/kernel-build-tools/linux-x86/lib64 -L $(BUILD_TOP)/prebuilts/kernel-build-tools/linux-x86/lib64 -fuse-ld=lld --rtlib=compiler-rt" |
| |
| TOOLS_PATH_OVERRIDE += PATH=$(BUILD_TOP)/prebuilts/tools-lineage/$(HOST_PREBUILT_TAG)/bin:$(TARGET_KERNEL_CLANG_PATH)/bin:$$PATH |
| endif |
| |
| # Set DTBO image locations so the build system knows to build them |
| ifeq (true,$(filter true, $(TARGET_NEEDS_DTBOIMAGE) $(BOARD_KERNEL_SEPARATED_DTBO))) |
| TARGET_KERNEL_DTBO_PREFIX ?= |
| TARGET_KERNEL_DTBO ?= dtbo.img |
| BOARD_PREBUILT_DTBOIMAGE ?= $(TARGET_OUT_INTERMEDIATES)/DTBO_OBJ/arch/$(KERNEL_ARCH)/boot/$(TARGET_KERNEL_DTBO_PREFIX)$(TARGET_KERNEL_DTBO) |
| endif |
| |
| # Set the default dtb target |
| TARGET_KERNEL_DTB ?= dtbs |
| |
| # Set no external modules by default |
| TARGET_KERNEL_EXT_MODULE_ROOT ?= |
| TARGET_KERNEL_EXT_MODULES ?= |
| |
| # Set use the full path to the make command |
| KERNEL_MAKE_CMD := $(BUILD_TOP)/prebuilts/build-tools/$(HOST_PREBUILT_TAG)/bin/make |
| |
| # Use LLVM's substitutes for GNU binutils |
| ifneq ($(TARGET_KERNEL_CLANG_COMPILE), false) |
| ifneq ($(TARGET_KERNEL_LLVM_BINUTILS), false) |
| KERNEL_MAKE_FLAGS += LLVM=1 LLVM_IAS=1 |
| endif |
| endif |
| |
| # Pass prebuilt LZ4 path |
| KERNEL_MAKE_FLAGS += LZ4=$(BUILD_TOP)/prebuilts/kernel-build-tools/linux-x86/bin/lz4 |
| |
| # Since Linux 4.16, flex and bison are required |
| KERNEL_MAKE_FLAGS += LEX=$(BUILD_TOP)/prebuilts/build-tools/$(HOST_PREBUILT_TAG)/bin/flex |
| KERNEL_MAKE_FLAGS += YACC=$(BUILD_TOP)/prebuilts/build-tools/$(HOST_PREBUILT_TAG)/bin/bison |
| KERNEL_MAKE_FLAGS += M4=$(BUILD_TOP)/prebuilts/build-tools/$(HOST_PREBUILT_TAG)/bin/m4 |
| TOOLS_PATH_OVERRIDE += BISON_PKGDATADIR=$(BUILD_TOP)/prebuilts/build-tools/common/bison |
| |
| # Since Linux 5.10, pahole is required |
| KERNEL_MAKE_FLAGS += PAHOLE=$(BUILD_TOP)/prebuilts/kernel-build-tools/linux-x86/bin/pahole |
| |
| # Set the out dir for the kernel's O= arg |
| # This needs to be an absolute path, so only set this if the standard out dir isn't used |
| OUT_DIR_PREFIX := $(shell echo $(OUT_DIR) | sed -e 's|/target/.*$$||g') |
| KERNEL_BUILD_OUT_PREFIX := |
| ifeq ($(OUT_DIR_PREFIX),out) |
| KERNEL_BUILD_OUT_PREFIX := $(BUILD_TOP)/ |
| endif |