package/pkg-kconfig.mk

   1 ################################################################################
   2 # Kconfig package infrastructure
   3 #
   4 # This file implements an infrastructure that eases development of
   5 # package .mk files for packages that use kconfig for configuration files.
   6 # It is based on the generic-package infrastructure, and inherits all of its
   7 # features.
   8 #
   9 # See the Buildroot documentation for details on the usage of this
  10 # infrastructure.
  11 #
  12 ################################################################################
  13
  14 ################################################################################
  15 # inner-kconfig-package -- generates the make targets needed to support a
  16 # kconfig package
  17 #
  18 #  argument 1 is the lowercase package name
  19 #  argument 2 is the uppercase package name, including a HOST_ prefix
  20 #             for host packages
  21 #  argument 3 is the uppercase package name, without the HOST_ prefix
  22 #             for host packages
  23 #  argument 4 is the type (target or host)
  24 ################################################################################
  25
  26 define inner-kconfig-package
  27
  28 # Call the generic package infrastructure to generate the necessary
  29 # make targets.
  30 # Note: this must be done _before_ attempting to use $$($(2)_DIR) in a
  31 # dependency expression
  32 $(call inner-generic-package,$(1),$(2),$(3),$(4))
  33
  34 # Default values
  35 $(2)_KCONFIG_EDITORS ?= menuconfig
  36 $(2)_KCONFIG_OPTS ?=
  37 $(2)_KCONFIG_FIXUP_CMDS ?=
  38 $(2)_KCONFIG_FRAGMENT_FILES ?=
  39
  40 # The config file as well as the fragments could be in-tree, so before
  41 # depending on them the package should be extracted (and patched) first.
  42 #
  43 # Since those files only have a order-only dependency, make would treat
  44 # any missing one as a "force" target:
  45 #   https://www.gnu.org/software/make/manual/make.html#Force-Targets
  46 # and would forcibly any rule that depend on those files, causing a
  47 # rebuild of the kernel each time make is called.
  48 #
  49 # So, we provide a recipe that checks all of those files exist, to
  50 # overcome that standard make behaviour.
  51 #
  52 $$($(2)_KCONFIG_FILE) $$($(2)_KCONFIG_FRAGMENT_FILES): | $(1)-patch
  53         for f in $$($(2)_KCONFIG_FILE) $$($(2)_KCONFIG_FRAGMENT_FILES); do \
  54                 if [ ! -f "$$$${f}" ]; then \
  55                         printf "Kconfig fragment '%s' for '%s' does not exist\n" "$$$${f}" "$(1)"; \
  56                         exit 1; \
  57                 fi; \
  58         done
  59
  60 $(2)_KCONFIG_MAKE = \
  61         $$($(2)_MAKE_ENV) $$(MAKE) -C $$($(2)_DIR) $$($(2)_KCONFIG_OPTS)
  62
  63 # $(2)_KCONFIG_MAKE may already rely on shell expansion. As the $() syntax
  64 # of the shell conflicts with Make's own syntax, this means that backticks
  65 # are used with those shell constructs. Unfortunately, the backtick syntax
  66 # does not nest, and we need to use Make instead of the shell to handle
  67 # conditions.
  68
  69 # A recursively expanded variable is necessary, to be sure that the shell
  70 # command is called when the rule is processed during the build and not
  71 # when the rule is created when parsing all packages.
  72 $(2)_KCONFIG_RULES = \
  73         $$(shell $$($(2)_KCONFIG_MAKE) -pn config 2>/dev/null | \
  74                 sed 's/^\([_0-9a-zA-Z]*config\):.*/\1/ p; d')
  75
  76 # The correct way to regenerate a .config file is to use 'make olddefconfig'.
  77 # For historical reasons, the target name is 'oldnoconfig' between Linux kernel
  78 # versions 2.6.36 and 3.6, and remains as an alias in later versions.
  79 # In older versions, and in some other projects that use kconfig, the target is
  80 # not supported at all, and we use 'yes "" | make oldconfig' as a fallback
  81 # only, as this can fail in complex cases.
  82 define $(2)_REGEN_DOT_CONFIG
  83         $$(if $$(filter olddefconfig,$$($(2)_KCONFIG_RULES)),
  84                 $$(Q)$$($(2)_KCONFIG_MAKE) olddefconfig,
  85                 $$(if $$(filter oldnoconfig,$$($(2)_KCONFIG_RULES)),
  86                         $$(Q)$$($(2)_KCONFIG_MAKE) oldnoconfig,
  87                         $$(Q)(yes "" | $$($(2)_KCONFIG_MAKE) oldconfig)))
  88 endef
  89
  90 # The specified source configuration file and any additional configuration file
  91 # fragments are merged together to .config, after the package has been patched.
  92 # Since the file could be a defconfig file it needs to be expanded to a
  93 # full .config first.
  94 $$($(2)_DIR)/.config: $$($(2)_KCONFIG_FILE) $$($(2)_KCONFIG_FRAGMENT_FILES)
  95         $$(Q)$$(if $$($(2)_KCONFIG_DEFCONFIG), \
  96                 $$($(2)_KCONFIG_MAKE) $$($(2)_KCONFIG_DEFCONFIG), \
  97                 cp $$($(2)_KCONFIG_FILE) $$(@))
  98         $$(Q)support/kconfig/merge_config.sh -m -O $$(@D) \
  99                 $$(@) $$($(2)_KCONFIG_FRAGMENT_FILES)
 100         $$($(2)_REGEN_DOT_CONFIG)
 101
 102 # If _KCONFIG_FILE or _KCONFIG_FRAGMENT_FILES exists, this dependency is
 103 # already implied, but if we only have a _KCONFIG_DEFCONFIG we have to add
 104 # it explicitly. It doesn't hurt to always have it though.
 105 $$($(2)_DIR)/.config: | $(1)-patch
 106
 107 # In order to get a usable, consistent configuration, some fixup may be needed.
 108 # The exact rules are specified by the package .mk file.
 109 define $(2)_FIXUP_DOT_CONFIG
 110         $$($(2)_KCONFIG_FIXUP_CMDS)
 111         $$($(2)_REGEN_DOT_CONFIG)
 112         $$(Q)touch $$($(2)_DIR)/.stamp_kconfig_fixup_done
 113 endef
 114
 115 $$($(2)_DIR)/.stamp_kconfig_fixup_done: $$($(2)_DIR)/.config
 116         $$($(2)_FIXUP_DOT_CONFIG)
 117
 118 # Before running configure, the configuration file should be present and fixed
 119 $$($(2)_TARGET_CONFIGURE): $$($(2)_DIR)/.stamp_kconfig_fixup_done
 120
 121 # Only enable the foo-*config targets when the package is actually enabled.
 122 # Note: the variable $(2)_KCONFIG_VAR is not related to the kconfig
 123 # infrastructure, but defined by pkg-generic.mk. The generic infrastructure is
 124 # already called above, so we can effectively use this variable.
 125 ifeq ($$($$($(2)_KCONFIG_VAR)),y)
 126
 127 ifeq ($$(BR_BUILDING),y)
 128 # Either FOO_KCONFIG_FILE or FOO_KCONFIG_DEFCONFIG is required...
 129 ifeq ($$(or $$($(2)_KCONFIG_FILE),$$($(2)_KCONFIG_DEFCONFIG)),)
 130 $$(error Internal error: no value specified for $(2)_KCONFIG_FILE or $(2)_KCONFIG_DEFCONFIG)
 131 endif
 132 # ... but not both:
 133 ifneq ($$(and $$($(2)_KCONFIG_FILE),$$($(2)_KCONFIG_DEFCONFIG)),)
 134 $$(error Internal error: $(2)_KCONFIG_FILE and $(2)_KCONFIG_DEFCONFIG are mutually exclusive but both are defined)
 135 endif
 136 endif
 137
 138 # For the configurators, we do want to use the system-provided host
 139 # tools, not the ones we build. This is particularly true for
 140 # pkg-config; if we use our pkg-config (from host-pkgconf), then it
 141 # would not look for the .pc from the host, but we do need them,
 142 # especially to find ncurses, GTK+, Qt (resp. for menuconfig and
 143 # nconfig, gconfig, xconfig).
 144 # So we simply remove our PATH and PKG_CONFIG_* variables.
 145 $(2)_CONFIGURATOR_MAKE_ENV = \
 146         $$(filter-out PATH=% PKG_CONFIG=% PKG_CONFIG_SYSROOT_DIR=% PKG_CONFIG_LIBDIR=%,$$($(2)_MAKE_ENV)) \
 147         PKG_CONFIG_PATH="$(HOST_PKG_CONFIG_PATH)"
 148
 149 # Configuration editors (menuconfig, ...)
 150 #
 151 # We need to apply the configuration fixups right after a configuration
 152 # editor exits, so that it is possible to save the configuration right
 153 # after exiting an editor, and so the user always sees a .config file
 154 # that is clean wrt. our requirements.
 155 #
 156 # Because commands in $(1)_FIXUP_KCONFIG are probably using $(@D), we
 157 # need to have a valid @D set. But, because the configurators rules are
 158 # not real files and do not contain the path to the package build dir,
 159 # @D would be just '.' in this case. So, we use an intermediate rule
 160 # with a stamp-like file which path is in the package build dir, so we
 161 # end up having a valid @D.
 162 #
 163 $$(addprefix $(1)-,$$($(2)_KCONFIG_EDITORS)): $(1)-%: $$($(2)_DIR)/.kconfig_editor_%
 164 $$($(2)_DIR)/.kconfig_editor_%: $$($(2)_DIR)/.stamp_kconfig_fixup_done
 165         $$($(2)_CONFIGURATOR_MAKE_ENV) $$(MAKE) -C $$($(2)_DIR) \
 166                 $$($(2)_KCONFIG_OPTS) $$(*)
 167         rm -f $$($(2)_DIR)/.stamp_{kconfig_fixup_done,configured,built}
 168         rm -f $$($(2)_DIR)/.stamp_{target,staging,images}_installed
 169         $$($(2)_FIXUP_DOT_CONFIG)
 170
 171 # Saving back the configuration
 172 #
 173 # Ideally, that should directly depend on $$($(2)_DIR)/.stamp_kconfig_fixup_done,
 174 # but that breaks the use-case in PR-8156 (from a clean tree):
 175 #   make menuconfig           <- enable kernel, use an in-tree defconfig, save and exit
 176 #   make linux-menuconfig     <- enable/disable whatever option, save and exit
 177 #   make menuconfig           <- change to use a custom defconfig file, set a path, save and exit
 178 #   make linux-update-config  <- should save to the new custom defconfig file
 179 #
 180 # Because of that use-case, saving the configuration can *not* directly
 181 # depend on the stamp file, because it itself depends on the .config,
 182 # which in turn depends on the (newly-set an non-existent) custom
 183 # defconfig file.
 184 #
 185 # Instead, we use an PHONY rule that will catch that situation.
 186 #
 187 $(1)-check-configuration-done:
 188         @if [ ! -f $$($(2)_DIR)/.stamp_kconfig_fixup_done ]; then \
 189                 echo "$(1) is not yet configured"; \
 190                 exit 1; \
 191         fi
 192
 193 $(1)-savedefconfig: $(1)-check-configuration-done
 194         $$($(2)_MAKE_ENV) $$(MAKE) -C $$($(2)_DIR) \
 195                 $$($(2)_KCONFIG_OPTS) savedefconfig
 196
 197 # Target to copy back the configuration to the source configuration file
 198 # Even though we could use 'cp --preserve-timestamps' here, the separate
 199 # cp and 'touch --reference' is used for symmetry with $(1)-update-defconfig.
 200 $(1)-update-config: $(1)-check-configuration-done
 201         @$$(if $$($(2)_KCONFIG_FRAGMENT_FILES), \
 202                 echo "Unable to perform $(1)-update-config when fragment files are set"; exit 1)
 203         @$$(if $$($(2)_KCONFIG_DEFCONFIG), \
 204                 echo "Unable to perform $(1)-update-config when using a defconfig rule"; exit 1)
 205         cp -f $$($(2)_DIR)/.config $$($(2)_KCONFIG_FILE)
 206         touch --reference $$($(2)_DIR)/.config $$($(2)_KCONFIG_FILE)
 207
 208 # Note: make sure the timestamp of the stored configuration is not newer than
 209 # the .config to avoid a useless rebuild. Note that, contrary to
 210 # $(1)-update-config, the reference for 'touch' is _not_ the file from which
 211 # we copy.
 212 $(1)-update-defconfig: $(1)-savedefconfig
 213         @$$(if $$($(2)_KCONFIG_FRAGMENT_FILES), \
 214                 echo "Unable to perform $(1)-update-defconfig when fragment files are set"; exit 1)
 215         @$$(if $$($(2)_KCONFIG_DEFCONFIG), \
 216                 echo "Unable to perform $(1)-update-defconfig when using a defconfig rule"; exit 1)
 217         cp -f $$($(2)_DIR)/defconfig $$($(2)_KCONFIG_FILE)
 218         touch --reference $$($(2)_DIR)/.config $$($(2)_KCONFIG_FILE)
 219
 220 endif # package enabled
 221
 222 .PHONY: \
 223         $(1)-update-config \
 224         $(1)-update-defconfig \
 225         $(1)-savedefconfig \
 226         $(1)-check-configuration-done \
 227         $$($(2)_DIR)/.kconfig_editor_% \
 228         $$(addprefix $(1)-,$$($(2)_KCONFIG_EDITORS))
 229
 230 endef # inner-kconfig-package
 231
 232 ################################################################################
 233 # kconfig-package -- the target generator macro for kconfig packages
 234 ################################################################################
 235
 236 kconfig-package = $(call inner-kconfig-package,$(pkgname),$(call UPPERCASE,$(pkgname)),$(call UPPERCASE,$(pkgname)),target)