core: More flexible kernel configuration

 * Allow various combinations of kernel vs. userspace architectures
 * Get rid of various assumptions about everything being ARM or 32-bit
 * This adds the following target flags:
     TARGET_KERNEL_ARCH
     TARGET_KERNEL_HEADER_ARCH
     KERNEL_HEADER_DEFCONFIG
     TARGET_KERNEL_CROSS_COMPILE_PREFIX

Change-Id: If0bc202abd35c216ba3ea5707ffdb602526d8ed3

1 files changed, 96 insertions, 34 deletions

diff --git a/core/tasks/kernel.mk b/core/tasks/kernel.mk
index e6be63a..9f40eec 100644
--- a/core/tasks/kernel.mk
+++ b/core/tasks/kernel.mk
@@ -29,14 +29,50 @@ SELINUX_DEFCONFIG := $(TARGET_KERNEL_SELINUX_CONFIG)
 KERNEL_OUT := $(TARGET_OUT_INTERMEDIATES)/KERNEL_OBJ
 KERNEL_CONFIG := $(KERNEL_OUT)/.config
 
+TARGET_KERNEL_ARCH := $(strip $(TARGET_KERNEL_ARCH))
+ifeq ($(TARGET_KERNEL_ARCH),)
+KERNEL_ARCH := $(TARGET_ARCH)
+else
+KERNEL_ARCH := $(TARGET_KERNEL_ARCH)
+endif
+
+TARGET_KERNEL_HEADER_ARCH := $(strip $(TARGET_KERNEL_HEADER_ARCH))
+ifeq ($(TARGET_KERNEL_HEADER_ARCH),)
+KERNEL_HEADER_ARCH := $(KERNEL_ARCH)
+else
+KERNEL_HEADER_ARCH := $(TARGET_KERNEL_HEADER_ARCH)
+endif
+
+KERNEL_HEADER_DEFCONFIG := $(strip $(KERNEL_HEADER_DEFCONFIG))
+ifeq ($(KERNEL_HEADER_DEFCONFIG),)
+KERNEL_HEADER_DEFCONFIG := $(KERNEL_DEFCONFIG)
+endif
+
+
 ifneq ($(BOARD_KERNEL_IMAGE_NAME),)
-	TARGET_PREBUILT_INT_KERNEL_TYPE := $(BOARD_KERNEL_IMAGE_NAME)
-	TARGET_PREBUILT_INT_KERNEL := $(KERNEL_OUT)/arch/$(TARGET_ARCH)/boot/$(TARGET_PREBUILT_INT_KERNEL_TYPE)
+  TARGET_PREBUILT_INT_KERNEL_TYPE := $(BOARD_KERNEL_IMAGE_NAME)
 else
-	TARGET_PREBUILT_INT_KERNEL := $(KERNEL_OUT)/arch/$(TARGET_ARCH)/boot/zImage
-	TARGET_PREBUILT_INT_KERNEL_TYPE := zImage
+  ifeq ($(TARGET_USES_UNCOMPRESSED_KERNEL),true)
+    TARGET_PREBUILT_INT_KERNEL_TYPE := Image
+  else
+    TARGET_PREBUILT_INT_KERNEL_TYPE := zImage
+  endif
+endif
+
+TARGET_PREBUILT_INT_KERNEL := $(KERNEL_OUT)/arch/$(KERNEL_ARCH)/boot/$(TARGET_PREBUILT_INT_KERNEL_TYPE)
+
+# Clear this first to prevent accidental poisoning from env
+MAKE_FLAGS :=
+
+ifeq ($(KERNEL_ARCH),arm64)
+  # Avoid "unsupported RELA relocation: 311" errors (R_AARCH64_ADR_GOT_PAGE)
+  MAKE_FLAGS += CFLAGS_MODULE="-fno-pic"
+  ifeq ($(TARGET_ARCH),arm)
+    KERNEL_CONFIG_OVERRIDE := CONFIG_ANDROID_BINDER_IPC_32BIT=y
+  endif
 endif
 
+
 ## Do be discontinued in a future version. Notify builder about target
 ## kernel format requirement
 ifeq ($(BOARD_KERNEL_IMAGE_NAME),)
@@ -97,12 +133,7 @@ else
     else
         #$(info Kernel source found, building it)
         FULL_KERNEL_BUILD := true
-        ifeq ($(TARGET_USES_UNCOMPRESSED_KERNEL),true)
-        $(info Using uncompressed kernel)
-            KERNEL_BIN := $(KERNEL_OUT)/piggy
-        else
-            KERNEL_BIN := $(TARGET_PREBUILT_INT_KERNEL)
-        endif
+        KERNEL_BIN := $(TARGET_PREBUILT_INT_KERNEL)
     endif
 endif
 
@@ -112,19 +143,38 @@ KERNEL_HEADERS_INSTALL := $(KERNEL_OUT)/usr
 KERNEL_MODULES_INSTALL := system
 KERNEL_MODULES_OUT := $(TARGET_OUT)/lib/modules
 
-ifeq ($(KERNEL_TOOLCHAIN),)
-KERNEL_TOOLCHAIN := $(ARM_EABI_TOOLCHAIN)
-endif
+TARGET_KERNEL_CROSS_COMPILE_PREFIX := $(strip $(TARGET_KERNEL_CROSS_COMPILE_PREFIX))
+ifeq ($(TARGET_KERNEL_CROSS_COMPILE_PREFIX),)
 ifeq ($(KERNEL_TOOLCHAIN_PREFIX),)
 KERNEL_TOOLCHAIN_PREFIX := arm-eabi-
 endif
+else
+KERNEL_TOOLCHAIN_PREFIX := $(TARGET_KERNEL_CROSS_COMPILE_PREFIX)
+endif
+
+ifeq ($(KERNEL_TOOLCHAIN),)
+KERNEL_TOOLCHAIN_PATH := $(KERNEL_TOOLCHAIN_PREFIX)
+else
+ifneq ($(KERNEL_TOOLCHAIN_PREFIX),)
+KERNEL_TOOLCHAIN_PATH := $(KERNEL_TOOLCHAIN)/$(KERNEL_TOOLCHAIN_PREFIX)
+endif
+endif
+
+ifneq ($(USE_CCACHE),)
+    ccache := $(ANDROID_BUILD_TOP)/prebuilts/misc/$(HOST_PREBUILT_TAG)/ccache/ccache
+    # Check that the executable is here.
+    ccache := $(strip $(wildcard $(ccache)))
+endif
+
+KERNEL_CROSS_COMPILE := CROSS_COMPILE="$(ccache) $(KERNEL_TOOLCHAIN_PATH)"
+ccache =
 
 define mv-modules
     mdpath=`find $(KERNEL_MODULES_OUT) -type f -name modules.order`;\
     if [ "$$mdpath" != "" ];then\
         mpath=`dirname $$mdpath`;\
         ko=`find $$mpath/kernel -type f -name *.ko`;\
-        for i in $$ko; do $(KERNEL_TOOLCHAIN)/$(KERNEL_TOOLCHAIN_PREFIX)strip --strip-unneeded $$i;\
+        for i in $$ko; do $(KERNEL_TOOLCHAIN_PATH)strip --strip-unneeded $$i;\
         mv $$i $(KERNEL_MODULES_OUT)/; done;\
     fi
 endef
@@ -136,18 +186,8 @@ define clean-module-folder
     fi
 endef
 
-ifeq ($(TARGET_ARCH),arm)
-    ifneq ($(USE_CCACHE),)
-      ccache := $(ANDROID_BUILD_TOP)/prebuilts/misc/$(HOST_PREBUILT_TAG)/ccache/ccache
-      # Check that the executable is here.
-      ccache := $(strip $(wildcard $(ccache)))
-    endif
-    ARM_CROSS_COMPILE:=CROSS_COMPILE="$(ccache) $(KERNEL_TOOLCHAIN)/$(KERNEL_TOOLCHAIN_PREFIX)"
-    ccache = 
-endif
-
 ifeq ($(HOST_OS),darwin)
-  MAKE_FLAGS := C_INCLUDE_PATH=$(ANDROID_BUILD_TOP)/external/elfutils/0.153/libelf/
+  MAKE_FLAGS += C_INCLUDE_PATH=$(ANDROID_BUILD_TOP)/external/elfutils/0.153/libelf/
 endif
 
 ifeq ($(TARGET_KERNEL_MODULES),)
@@ -159,16 +199,17 @@ $(KERNEL_OUT):
 	mkdir -p $(KERNEL_MODULES_OUT)
 
 $(KERNEL_CONFIG): $(KERNEL_OUT)
-	$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(TARGET_ARCH) $(ARM_CROSS_COMPILE) VARIANT_DEFCONFIG=$(VARIANT_DEFCONFIG) SELINUX_DEFCONFIG=$(SELINUX_DEFCONFIG) $(KERNEL_DEFCONFIG)
-
-$(KERNEL_OUT)/piggy : $(TARGET_PREBUILT_INT_KERNEL)
-	$(hide) gunzip -c $(KERNEL_OUT)/arch/$(TARGET_ARCH)/boot/compressed/piggy.gzip > $(KERNEL_OUT)/piggy
+	$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) VARIANT_DEFCONFIG=$(VARIANT_DEFCONFIG) SELINUX_DEFCONFIG=$(SELINUX_DEFCONFIG) $(KERNEL_DEFCONFIG)
+	$(hide) if [ ! -z "$(KERNEL_CONFIG_OVERRIDE)" ]; then \
+			echo "Overriding kernel config with '$(KERNEL_CONFIG_OVERRIDE)'"; \
+			echo $(KERNEL_CONFIG_OVERRIDE) >> $(KERNEL_OUT)/.config; \
+			$(MAKE) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) oldconfig; fi
 
 TARGET_KERNEL_BINARIES: $(KERNEL_OUT) $(KERNEL_CONFIG) $(KERNEL_HEADERS_INSTALL)
-	$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(TARGET_ARCH) $(ARM_CROSS_COMPILE) $(TARGET_PREBUILT_INT_KERNEL_TYPE)
-	-$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(TARGET_ARCH) $(ARM_CROSS_COMPILE) dtbs
-	-$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(TARGET_ARCH) $(ARM_CROSS_COMPILE) modules
-	-$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) INSTALL_MOD_PATH=../../$(KERNEL_MODULES_INSTALL) ARCH=$(TARGET_ARCH) $(ARM_CROSS_COMPILE) modules_install
+	$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) $(TARGET_PREBUILT_INT_KERNEL_TYPE)
+	-$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) dtbs
+	-$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) modules
+	-$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) INSTALL_MOD_PATH=../../$(KERNEL_MODULES_INSTALL) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) modules_install
 	$(mv-modules)
 	$(clean-module-folder)
 
@@ -179,7 +220,28 @@ $(TARGET_PREBUILT_INT_KERNEL): $(TARGET_KERNEL_MODULES)
 	$(clean-module-folder)
 
 $(KERNEL_HEADERS_INSTALL): $(KERNEL_OUT) $(KERNEL_CONFIG)
-	$(MAKE) $(MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(TARGET_ARCH) $(ARM_CROSS_COMPILE) headers_install
+	$(hide) if [ ! -z "$(KERNEL_HEADER_DEFCONFIG)" ]; then \
+			$(hide) rm -f ../$(KERNEL_CONFIG); \
+			$(MAKE) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_HEADER_ARCH) $(KERNEL_CROSS_COMPILE) $(KERNEL_HEADER_DEFCONFIG); \
+			$(MAKE) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_HEADER_ARCH) $(KERNEL_CROSS_COMPILE) headers_install; fi
+	$(hide) if [ "$(KERNEL_HEADER_DEFCONFIG)" != "$(KERNEL_DEFCONFIG)" ]; then \
+			echo "Used a different defconfig for header generation"; \
+			$(hide) rm -f ../$(KERNEL_CONFIG); \
+			$(MAKE) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) $(KERNEL_DEFCONFIG); fi
+	$(hide) if [ ! -z "$(KERNEL_CONFIG_OVERRIDE)" ]; then \
+			echo "Overriding kernel config with '$(KERNEL_CONFIG_OVERRIDE)'"; \
+			echo $(KERNEL_CONFIG_OVERRIDE) >> $(KERNEL_OUT)/.config; \
+			$(MAKE) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) oldconfig; fi
+
+kerneltags: $(KERNEL_OUT) $(KERNEL_CONFIG)
+	$(MAKE) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) tags
+
+kernelconfig: $(KERNEL_OUT) $(KERNEL_CONFIG)
+	env KCONFIG_NOTIMESTAMP=true \
+		 $(MAKE) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) menuconfig
+	env KCONFIG_NOTIMESTAMP=true \
+		 $(MAKE) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) savedefconfig
+	cp $(KERNEL_OUT)/defconfig kernel/arch/$(KERNEL_ARCH)/configs/$(KERNEL_DEFCONFIG)
 
 endif # FULL_KERNEL_BUILD