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 $$($(2)_DIR) in a
  31 # dependency expression
  32 $(call inner-generic-package,$(1),$(2),$(3),$(4))
  33
  34 # Default values
  35 $(2)_KCONFIG_EDITORS ?= menuconfig
  36 $(2)_KCONFIG_OPTS ?=
  37 $(2)_KCONFIG_FIXUP_CMDS ?=
  38 $(2)_KCONFIG_FRAGMENT_FILES ?=
  39 $(2)_KCONFIG_DOTCONFIG ?= .config
  40
  41 # The config file as well as the fragments could be in-tree, so before
  42 # depending on them the package should be extracted (and patched) first.
  43 #
  44 # Since those files only have a order-only dependency, make would treat
  45 # any missing one as a "force" target:
  46 #   https://www.gnu.org/software/make/manual/make.html#Force-Targets
  47 # and would forcibly any rule that depend on those files, causing a
  48 # rebuild of the kernel each time make is called.
  49 #
  50 # So, we provide a recipe that checks all of those files exist, to
  51 # overcome that standard make behaviour.
  52 #
  53 $$($(2)_KCONFIG_FILE) $$($(2)_KCONFIG_FRAGMENT_FILES): | $(1)-patch
  54         for f in $$($(2)_KCONFIG_FILE) $$($(2)_KCONFIG_FRAGMENT_FILES); do \
  55                 if [ ! -f "$$$${f}" ]; then \
  56                         printf "Kconfig fragment '%s' for '%s' does not exist\n" "$$$${f}" "$(1)"; \
  57                         exit 1; \
  58                 fi; \
  59         done
  60
  61 $(2)_KCONFIG_MAKE = \
  62         $$($(2)_MAKE_ENV) $$(MAKE) -C $$($(2)_DIR) $$($(2)_KCONFIG_OPTS)
  63
  64 # $(2)_KCONFIG_MAKE may already rely on shell expansion. As the $() syntax
  65 # of the shell conflicts with Make's own syntax, this means that backticks
  66 # are used with those shell constructs. Unfortunately, the backtick syntax
  67 # does not nest, and we need to use Make instead of the shell to handle
  68 # conditions.
  69
  70 # A recursively expanded variable is necessary, to be sure that the shell
  71 # command is called when the rule is processed during the build and not
  72 # when the rule is created when parsing all packages.
  73 $(2)_KCONFIG_RULES = \
  74         $$(shell $$($(2)_KCONFIG_MAKE) -pn config 2>/dev/null | \
  75                 sed 's/^\([_0-9a-zA-Z]*config\):.*/\1/ p; d')
  76
  77 # The correct way to regenerate a .config file is to use 'make olddefconfig'.
  78 # For historical reasons, the target name is 'oldnoconfig' between Linux kernel
  79 # versions 2.6.36 and 3.6, and remains as an alias in later versions.
  80 # In older versions, and in some other projects that use kconfig, the target is
  81 # not supported at all, and we use 'yes "" | make oldconfig' as a fallback
  82 # only, as this can fail in complex cases.
  83 define $(2)_REGEN_DOT_CONFIG
  84         $$(if $$(filter olddefconfig,$$($(2)_KCONFIG_RULES)),
  85                 $$(Q)$$($(2)_KCONFIG_MAKE) olddefconfig,
  86                 $$(if $$(filter oldnoconfig,$$($(2)_KCONFIG_RULES)),
  87                         $$(Q)$$($(2)_KCONFIG_MAKE) oldnoconfig,
  88                         $$(Q)(yes "" | $$($(2)_KCONFIG_MAKE) oldconfig)))
  89 endef
  90
  91 # The specified source configuration file and any additional configuration file
  92 # fragments are merged together to .config, after the package has been patched.
  93 # Since the file could be a defconfig file it needs to be expanded to a
  94 # full .config first.
  95 $$($(2)_DIR)/$$($(2)_KCONFIG_DOTCONFIG): $$($(2)_KCONFIG_FILE) $$($(2)_KCONFIG_FRAGMENT_FILES)
  96         $$(Q)$$(if $$($(2)_KCONFIG_DEFCONFIG), \
  97                 $$($(2)_KCONFIG_MAKE) $$($(2)_KCONFIG_DEFCONFIG), \
  98                 $$(INSTALL) -m 0644 -D $$($(2)_KCONFIG_FILE) $$(@))
  99         $$(Q)support/kconfig/merge_config.sh -m -O $$(@D) \
 100                 $$(@) $$($(2)_KCONFIG_FRAGMENT_FILES)
 101         $$($(2)_REGEN_DOT_CONFIG)
 102
 103 # If _KCONFIG_FILE or _KCONFIG_FRAGMENT_FILES exists, this dependency is
 104 # already implied, but if we only have a _KCONFIG_DEFCONFIG we have to add
 105 # it explicitly. It doesn't hurt to always have it though.
 106 $$($(2)_DIR)/$$($(2)_KCONFIG_DOTCONFIG): | $(1)-patch
 107
 108 # In order to get a usable, consistent configuration, some fixup may be needed.
 109 # The exact rules are specified by the package .mk file.
 110 define $(2)_FIXUP_DOT_CONFIG
 111         $$($(2)_KCONFIG_FIXUP_CMDS)
 112         $$($(2)_REGEN_DOT_CONFIG)
 113         $$(Q)touch $$($(2)_DIR)/.stamp_kconfig_fixup_done
 114 endef
 115
 116 $$($(2)_DIR)/.stamp_kconfig_fixup_done: $$($(2)_DIR)/$$($(2)_KCONFIG_DOTCONFIG)
 117         $$($(2)_FIXUP_DOT_CONFIG)
 118
 119 # Before running configure, the configuration file should be present and fixed
 120 $$($(2)_TARGET_CONFIGURE): $$($(2)_DIR)/.stamp_kconfig_fixup_done
 121
 122 # Force olddefconfig again on -reconfigure
 123 $(1)-clean-for-reconfigure: $(1)-clean-kconfig-for-reconfigure
 124
 125 $(1)-clean-kconfig-for-reconfigure:
 126         rm -f $$($(2)_DIR)/.stamp_kconfig_fixup_done
 127
 128 # Only enable the foo-*config targets when the package is actually enabled.
 129 # Note: the variable $(2)_KCONFIG_VAR is not related to the kconfig
 130 # infrastructure, but defined by pkg-generic.mk. The generic infrastructure is
 131 # already called above, so we can effectively use this variable.
 132 ifeq ($$($$($(2)_KCONFIG_VAR)),y)
 133
 134 ifeq ($$(BR_BUILDING),y)
 135 # Either FOO_KCONFIG_FILE or FOO_KCONFIG_DEFCONFIG is required...
 136 ifeq ($$(or $$($(2)_KCONFIG_FILE),$$($(2)_KCONFIG_DEFCONFIG)),)
 137 $$(error Internal error: no value specified for $(2)_KCONFIG_FILE or $(2)_KCONFIG_DEFCONFIG)
 138 endif
 139 # ... but not both:
 140 ifneq ($$(and $$($(2)_KCONFIG_FILE),$$($(2)_KCONFIG_DEFCONFIG)),)
 141 $$(error Internal error: $(2)_KCONFIG_FILE and $(2)_KCONFIG_DEFCONFIG are mutually exclusive but both are defined)
 142 endif
 143 endif
 144
 145 # For the configurators, we do want to use the system-provided host
 146 # tools, not the ones we build. This is particularly true for
 147 # pkg-config; if we use our pkg-config (from host-pkgconf), then it
 148 # would not look for the .pc from the host, but we do need them,
 149 # especially to find ncurses, GTK+, Qt (resp. for menuconfig and
 150 # nconfig, gconfig, xconfig).
 151 # So we simply remove our PATH and PKG_CONFIG_* variables.
 152 $(2)_CONFIGURATOR_MAKE_ENV = \
 153         $$(filter-out PATH=% PKG_CONFIG=% PKG_CONFIG_SYSROOT_DIR=% PKG_CONFIG_LIBDIR=%,$$($(2)_MAKE_ENV)) \
 154         PKG_CONFIG_PATH="$(HOST_PKG_CONFIG_PATH)"
 155
 156 # Configuration editors (menuconfig, ...)
 157 #
 158 # We need to apply the configuration fixups right after a configuration
 159 # editor exits, so that it is possible to save the configuration right
 160 # after exiting an editor, and so the user always sees a .config file
 161 # that is clean wrt. our requirements.
 162 #
 163 # Because commands in $(1)_FIXUP_KCONFIG are probably using $(@D), we
 164 # need to have a valid @D set. But, because the configurators rules are
 165 # not real files and do not contain the path to the package build dir,
 166 # @D would be just '.' in this case. So, we use an intermediate rule
 167 # with a stamp-like file which path is in the package build dir, so we
 168 # end up having a valid @D.
 169 #
 170 $$(addprefix $(1)-,$$($(2)_KCONFIG_EDITORS)): $(1)-%: $$($(2)_DIR)/.kconfig_editor_%
 171 $$($(2)_DIR)/.kconfig_editor_%: $$($(2)_DIR)/.stamp_kconfig_fixup_done
 172         $$($(2)_CONFIGURATOR_MAKE_ENV) $$(MAKE) -C $$($(2)_DIR) \
 173                 $$($(2)_KCONFIG_OPTS) $$(*)
 174         rm -f $$($(2)_DIR)/.stamp_{kconfig_fixup_done,configured,built}
 175         rm -f $$($(2)_DIR)/.stamp_{target,staging,images}_installed
 176         $$($(2)_FIXUP_DOT_CONFIG)
 177
 178 # Saving back the configuration
 179 #
 180 # Ideally, that should directly depend on $$($(2)_DIR)/.stamp_kconfig_fixup_done,
 181 # but that breaks the use-case in PR-8156 (from a clean tree):
 182 #   make menuconfig           <- enable kernel, use an in-tree defconfig, save and exit
 183 #   make linux-menuconfig     <- enable/disable whatever option, save and exit
 184 #   make menuconfig           <- change to use a custom defconfig file, set a path, save and exit
 185 #   make linux-update-config  <- should save to the new custom defconfig file
 186 #
 187 # Because of that use-case, saving the configuration can *not* directly
 188 # depend on the stamp file, because it itself depends on the .config,
 189 # which in turn depends on the (newly-set an non-existent) custom
 190 # defconfig file.
 191 #
 192 # Instead, we use an PHONY rule that will catch that situation.
 193 #
 194 $(1)-check-configuration-done:
 195         @if [ ! -f $$($(2)_DIR)/.stamp_kconfig_fixup_done ]; then \
 196                 echo "$(1) is not yet configured"; \
 197                 exit 1; \
 198         fi
 199
 200 $(1)-savedefconfig: $(1)-check-configuration-done
 201         $$($(2)_MAKE_ENV) $$(MAKE) -C $$($(2)_DIR) \
 202                 $$($(2)_KCONFIG_OPTS) savedefconfig
 203
 204 # Target to copy back the configuration to the source configuration file
 205 # Even though we could use 'cp --preserve-timestamps' here, the separate
 206 # cp and 'touch --reference' is used for symmetry with $(1)-update-defconfig.
 207 $(1)-update-config: $(1)-check-configuration-done
 208         @$$(if $$($(2)_KCONFIG_FRAGMENT_FILES), \
 209                 echo "Unable to perform $(1)-update-config when fragment files are set"; exit 1)
 210         @$$(if $$($(2)_KCONFIG_DEFCONFIG), \
 211                 echo "Unable to perform $(1)-update-config when using a defconfig rule"; exit 1)
 212         cp -f $$($(2)_DIR)/$$($(2)_KCONFIG_DOTCONFIG) $$($(2)_KCONFIG_FILE)
 213         touch --reference $$($(2)_DIR)/$$($(2)_KCONFIG_DOTCONFIG) $$($(2)_KCONFIG_FILE)
 214
 215 # Note: make sure the timestamp of the stored configuration is not newer than
 216 # the .config to avoid a useless rebuild. Note that, contrary to
 217 # $(1)-update-config, the reference for 'touch' is _not_ the file from which
 218 # we copy.
 219 $(1)-update-defconfig: $(1)-savedefconfig
 220         @$$(if $$($(2)_KCONFIG_FRAGMENT_FILES), \
 221                 echo "Unable to perform $(1)-update-defconfig when fragment files are set"; exit 1)
 222         @$$(if $$($(2)_KCONFIG_DEFCONFIG), \
 223                 echo "Unable to perform $(1)-update-defconfig when using a defconfig rule"; exit 1)
 224         cp -f $$($(2)_DIR)/defconfig $$($(2)_KCONFIG_FILE)
 225         touch --reference $$($(2)_DIR)/$$($(2)_KCONFIG_DOTCONFIG) $$($(2)_KCONFIG_FILE)
 226
 227 endif # package enabled
 228
 229 .PHONY: \
 230         $(1)-update-config \
 231         $(1)-update-defconfig \
 232         $(1)-savedefconfig \
 233         $(1)-check-configuration-done \
 234         $$($(2)_DIR)/.kconfig_editor_% \
 235         $$(addprefix $(1)-,$$($(2)_KCONFIG_EDITORS))
 236
 237 endef # inner-kconfig-package
 238
 239 ################################################################################
 240 # kconfig-package -- the target generator macro for kconfig packages
 241 ################################################################################
 242
 243 kconfig-package = $(call inner-kconfig-package,$(pkgname),$(call UPPERCASE,$(pkgname)),$(call UPPERCASE,$(pkgname)),target)