kernel.mk

#
# Copyright (C) 2006-2015 OpenWrt.org
#
# This is free software, licensed under the GNU General Public License v2.
# See /LICENSE for more information.
#

ifneq ($(filter check,$(MAKECMDGOALS)),)
CHECK:=1
DUMP:=1
endif

ifneq ($(SOURCE_DATE_EPOCH),)
  ifndef DUMP
    KBUILD_BUILD_TIMESTAMP:=$(shell perl -e 'print scalar gmtime($(SOURCE_DATE_EPOCH))')
  endif
endif

ifeq ($(__target_inc),)
  ifndef CHECK
    include $(INCLUDE_DIR)/target.mk
  endif
endif

ifeq ($(DUMP),1)
  KERNEL?=<KERNEL>
  BOARD?=<BOARD>
  LINUX_VERSION?=<LINUX_VERSION>
  LINUX_VERMAGIC?=<LINUX_VERMAGIC>
else
  ifeq ($(CONFIG_EXTERNAL_TOOLCHAIN),)
    export GCC_HONOUR_COPTS=s
  endif

  LINUX_KMOD_SUFFIX=ko

  ifneq (,$(findstring uml,$(BOARD)))
    KERNEL_CC?=$(HOSTCC)
    KERNEL_CROSS?=
  else
    KERNEL_CC?=$(TARGET_CC)
    KERNEL_CROSS?=$(TARGET_CROSS)
  endif

  ifeq ($(TARGET_BUILD),1)
    PATCH_DIR ?= $(CURDIR)/patches$(if $(wildcard ./patches-$(KERNEL_PATCHVER)),-$(KERNEL_PATCHVER))
    FILES_DIR ?= $(foreach dir,$(wildcard $(CURDIR)/files $(CURDIR)/files-$(KERNEL_PATCHVER)),"$(dir)")
  endif
  KERNEL_BUILD_DIR ?= $(BUILD_DIR)/linux-$(BOARD)$(if $(SUBTARGET),_$(SUBTARGET))
  LINUX_DIR ?= $(KERNEL_BUILD_DIR)/linux-$(LINUX_VERSION)
  LINUX_UAPI_DIR=uapi/
  LINUX_VERMAGIC:=$(strip $(shell cat $(LINUX_DIR)/.vermagic 2>/dev/null))
  LINUX_VERMAGIC:=$(if $(LINUX_VERMAGIC),$(LINUX_VERMAGIC),unknown)

  LINUX_UNAME_VERSION:=$(if $(word 3,$(subst ., ,$(KERNEL_BASE))),$(KERNEL_BASE),$(KERNEL_BASE).0)
  ifneq ($(findstring -rc,$(LINUX_VERSION)),)
    LINUX_UNAME_VERSION:=$(LINUX_UNAME_VERSION)-$(strip $(lastword $(subst -, ,$(LINUX_VERSION))))
  endif

  LINUX_KERNEL:=$(KERNEL_BUILD_DIR)/vmlinux

  LINUX_SOURCE:=linux-$(LINUX_VERSION).tar.xz
  TESTING:=$(if $(findstring -rc,$(LINUX_VERSION)),/testing,)
  ifeq ($(call qstrip,$(CONFIG_EXTERNAL_KERNEL_TREE))$(call qstrip,$(CONFIG_KERNEL_GIT_CLONE_URI)),)
      LINUX_SITE:=@KERNEL/linux/kernel/v$(word 1,$(subst ., ,$(KERNEL_BASE))).x$(TESTING)
  else
      LINUX_UNAME_VERSION:=$(strip $(shell cat $(LINUX_DIR)/include/config/kernel.release))
  endif

  MODULES_SUBDIR:=lib/modules/$(LINUX_UNAME_VERSION)
  TARGET_MODULES_DIR:=$(LINUX_TARGET_DIR)/$(MODULES_SUBDIR)

  ifneq ($(TARGET_BUILD),1)
    PKG_BUILD_DIR ?= $(KERNEL_BUILD_DIR)/$(PKG_NAME)$(if $(PKG_VERSION),-$(PKG_VERSION))
  endif
endif

ifneq (,$(findstring uml,$(BOARD)))
  LINUX_KARCH=um
else ifneq (,$(findstring $(ARCH) , aarch64 aarch64_be ))
  LINUX_KARCH := arm64
else ifneq (,$(findstring $(ARCH) , arceb ))
  LINUX_KARCH := arc
else ifneq (,$(findstring $(ARCH) , armeb ))
  LINUX_KARCH := arm
else ifneq (,$(findstring $(ARCH) , mipsel mips64 mips64el ))
  LINUX_KARCH := mips
else ifneq (,$(findstring $(ARCH) , sh2 sh3 sh4 ))
  LINUX_KARCH := sh
else ifneq (,$(findstring $(ARCH) , i386 x86_64 ))
  LINUX_KARCH := x86
else
  LINUX_KARCH := $(ARCH)
endif

KERNEL_MAKE = $(MAKE) $(KERNEL_MAKEOPTS)

KERNEL_MAKE_FLAGS := \
	HOSTCFLAGS="$(HOST_CFLAGS) -Wall -Wmissing-prototypes -Wstrict-prototypes" \
	CROSS_COMPILE="$(KERNEL_CROSS)" \
	ARCH="$(LINUX_KARCH)" \
	KBUILD_HAVE_NLS=no \
	KBUILD_BUILD_USER="$(call qstrip,$(CONFIG_KERNEL_BUILD_USER))" \
	KBUILD_BUILD_HOST="$(call qstrip,$(CONFIG_KERNEL_BUILD_DOMAIN))" \
	KBUILD_BUILD_TIMESTAMP="$(KBUILD_BUILD_TIMESTAMP)" \
	KBUILD_BUILD_VERSION="0" \
	HOST_LOADLIBES="-L$(STAGING_DIR_HOST)/lib" \
	CONFIG_SHELL="$(BASH)" \
	$(if $(findstring c,$(OPENWRT_VERBOSE)),V=1,V='') \
	$(if $(PKG_BUILD_ID),LDFLAGS_MODULE=--build-id=0x$(PKG_BUILD_ID)) \
	cmd_syscalls=

ifeq ($(call qstrip,$(CONFIG_EXTERNAL_KERNEL_TREE))$(call qstrip,$(CONFIG_KERNEL_GIT_CLONE_URI)),)
  KERNEL_MAKE_FLAGS += \
	KERNELRELEASE=$(LINUX_VERSION)
endif

KERNEL_MAKEOPTS := -C $(LINUX_DIR) $(KERNEL_MAKE_FLAGS)

ifdef CONFIG_USE_SPARSE
  KERNEL_MAKEOPTS += C=1 CHECK=$(STAGING_DIR_HOST)/bin/sparse
endif

define KernelPackage/Defaults
  FILES:=
  AUTOLOAD:=
  PKGFLAGS+=nonshared
endef

define ModuleAutoLoad
	$(SH_FUNC) \
	export modules=; \
	probe_module() { \
		local mods="$$$$$$$$1"; \
		local boot="$$$$$$$$2"; \
		local mod; \
		shift 2; \
		for mod in $$$$$$$$mods; do \
			mkdir -p $(2)/etc/modules.d; \
			echo "$$$$$$$$mod" >> $(2)/etc/modules.d/$(1); \
		done; \
		if [ -e $(2)/etc/modules.d/$(1) ]; then \
			if [ "$$$$$$$$boot" = "1" -a ! -e $(2)/etc/modules-boot.d/$(1) ]; then \
				mkdir -p $(2)/etc/modules-boot.d; \
				ln -s ../modules.d/$(1) $(2)/etc/modules-boot.d/; \
			fi; \
			modules="$$$$$$$${modules:+$$$$$$$$modules }$$$$$$$$mods"; \
		fi; \
	}; \
	add_module() { \
		local priority="$$$$$$$$1"; \
		local mods="$$$$$$$$2"; \
		local boot="$$$$$$$$3"; \
		local mod; \
		shift 3; \
		for mod in $$$$$$$$mods; do \
			mkdir -p $(2)/etc/modules.d; \
			echo "$$$$$$$$mod" >> $(2)/etc/modules.d/$$$$$$$$priority-$(1); \
		done; \
		if [ -e $(2)/etc/modules.d/$$$$$$$$priority-$(1) ]; then \
			if [ "$$$$$$$$boot" = "1" -a ! -e $(2)/etc/modules-boot.d/$$$$$$$$priority-$(1) ]; then \
				mkdir -p $(2)/etc/modules-boot.d; \
				ln -s ../modules.d/$$$$$$$$priority-$(1) $(2)/etc/modules-boot.d/; \
			fi; \
			modules="$$$$$$$${modules:+$$$$$$$$modules }$$$$$$$$priority-$(1)"; \
		fi; \
	}; \
	$(3) \
	if [ -n "$$$$$$$$modules" ]; then \
		modules="$$$$$$$$(echo "$$$$$$$$modules" | tr ' ' '\n' | sort | uniq | paste -s -d' ' -)"; \
		mkdir -p $(2)/etc/modules.d; \
		mkdir -p $(2)/CONTROL; \
		echo "#!/bin/sh" > $(2)/CONTROL/postinst-pkg; \
		echo "[ -z \"\$$$$$$$$IPKG_INSTROOT\" ] || exit 0" >> $(2)/CONTROL/postinst-pkg; \
		echo ". /lib/functions.sh" >> $(2)/CONTROL/postinst-pkg; \
		echo "insert_modules $$$$$$$$modules" >> $(2)/CONTROL/postinst-pkg; \
		chmod 0755 $(2)/CONTROL/postinst-pkg; \
	fi
endef

ifeq ($(DUMP)$(TARGET_BUILD),)
  -include $(LINUX_DIR)/.config
endif

define KernelPackage/depends
  $(STAMP_BUILT): $(LINUX_DIR)/.config
  define KernelPackage/depends
  endef
endef

define KernelPackage
  NAME:=$(1)
  $(eval $(call Package/Default))
  $(eval $(call KernelPackage/Defaults))
  $(eval $(call KernelPackage/$(1)))
  $(eval $(call KernelPackage/$(1)/$(BOARD)))
  $(eval $(call KernelPackage/$(1)/$(BOARD)/$(if $(SUBTARGET),$(SUBTARGET),generic)))

  define Package/kmod-$(1)
    TITLE:=$(TITLE)
    SECTION:=kernel
    CATEGORY:=Kernel modules
    DESCRIPTION:=$(DESCRIPTION)
    EXTRA_DEPENDS:=kernel (=$(LINUX_VERSION)-$(LINUX_RELEASE)-$(LINUX_VERMAGIC))
    VERSION:=$(LINUX_VERSION)$(if $(PKG_VERSION),+$(PKG_VERSION))-$(if $(PKG_RELEASE),$(PKG_RELEASE),$(LINUX_RELEASE))
    PKGFLAGS:=$(PKGFLAGS)
    $(call KernelPackage/$(1))
    $(call KernelPackage/$(1)/$(BOARD))
    $(call KernelPackage/$(1)/$(BOARD)/$(if $(SUBTARGET),$(SUBTARGET),generic))
  endef

  ifdef KernelPackage/$(1)/conffiles
    define Package/kmod-$(1)/conffiles
$(call KernelPackage/$(1)/conffiles)
    endef
  endif

  ifdef KernelPackage/$(1)/description
    define Package/kmod-$(1)/description
$(call KernelPackage/$(1)/description)
    endef
  endif

  ifdef KernelPackage/$(1)/config
    define Package/kmod-$(1)/config
$(call KernelPackage/$(1)/config)
    endef
  endif

  $(call KernelPackage/depends)

  ifneq ($(if $(filter-out %=y %=n %=m,$(KCONFIG)),$(filter m y,$(foreach c,$(filter-out %=y %=n %=m,$(KCONFIG)),$($(c)))),.),)
    ifneq ($(strip $(FILES)),)
      define Package/kmod-$(1)/install
		  @for mod in $$(call version_filter,$$(FILES)); do \
			if grep -q "$$$$$$$${mod##$(LINUX_DIR)/}" "$(LINUX_DIR)/modules.builtin"; then \
				echo "NOTICE: module '$$$$$$$$mod' is built-in."; \
			elif [ -e $$$$$$$$mod ]; then \
				mkdir -p $$(1)/$(MODULES_SUBDIR) ; \
				$(CP) -L $$$$$$$$mod $$(1)/$(MODULES_SUBDIR)/ ; \
			else \
				echo "ERROR: module '$$$$$$$$mod' is missing." >&2; \
				exit 1; \
			fi; \
		  done;
		  $(call ModuleAutoLoad,$(1),$$(1),$(AUTOLOAD))
		  $(call KernelPackage/$(1)/install,$$(1))
      endef
    endif
  $(if $(CONFIG_PACKAGE_kmod-$(1)),
    else
      compile: $(1)-disabled
      $(1)-disabled:
		@echo "WARNING: kmod-$(1) is not available in the kernel config - generating empty package" >&2

      define Package/kmod-$(1)/install
		true
      endef
  )
  endif
  $$(eval $$(call BuildPackage,kmod-$(1)))

  $$(IPKG_kmod-$(1)): $$(wildcard $$(FILES))
endef

version_filter=$(if $(findstring @,$(1)),$(shell $(SCRIPT_DIR)/package-metadata.pl version_filter $(KERNEL_PATCHVER) $(1)),$(1))

define AutoLoad
  add_module "$(1)" "$(call version_filter,$(2))" "$(3)";
endef

define AutoProbe
  probe_module "$(call version_filter,$(1))" "$(2)";
endef

version_field=$(if $(word $(1),$(2)),$(word $(1),$(2)),0)
kernel_version_merge=$$(( ($(call version_field,1,$(1)) << 24) + ($(call version_field,2,$(1)) << 16) + ($(call version_field,3,$(1)) << 8) + $(call version_field,4,$(1)) ))

ifdef DUMP
  kernel_version_cmp=
else
  kernel_version_cmp=$(shell [ $(call kernel_version_merge,$(call split_version,$(2))) $(1) $(call kernel_version_merge,$(call split_version,$(3))) ] && echo 1 )
endif

CompareKernelPatchVer=$(if $(call kernel_version_cmp,-$(2),$(1),$(3)),1,0)

kernel_patchver_gt=$(call kernel_version_cmp,-gt,$(KERNEL_PATCHVER),$(1))
kernel_patchver_ge=$(call kernel_version_cmp,-ge,$(KERNEL_PATCHVER),$(1))
kernel_patchver_eq=$(call kernel_version_cmp,-eq,$(KERNEL_PATCHVER),$(1))
kernel_patchver_le=$(call kernel_version_cmp,-le,$(KERNEL_PATCHVER),$(1))
kernel_patchver_lt=$(call kernel_version_cmp,-lt,$(KERNEL_PATCHVER),$(1))