kconfig: Move Kconfig.modules to the root build directory

Currently, the Kconfig.modules file is placed in the build directory
relative to the CMake "project". But technically, the file is not
project-specific, but global, or build-directory specific.

So we move it up one level to the CMAKE_BINARY_DIR instead. Currently,
there is only one project, so this change has no effect, but this
enables us to have multiple projects in the future, which again
enables multi-image builds.

Signed-off-by: Sebastian Bøe <[email protected]>
Signed-off-by: Håkon Øye Amundsen <[email protected]>

Author: SebastianBoe

Kconfig.zephyr

@@ -7,7 +7,7 @@
 # SPDX-License-Identifier: Apache-2.0
 #
 
-source "$(PROJECT_BINARY_DIR)/Kconfig.modules"
+source "$(CMAKE_BINARY_DIR)/Kconfig.modules"
 
 # Include these first so that any properties (e.g. defaults) below can be
 # overriden in *.defconfig files (by defining symbols in multiple locations).

cmake/kconfig.cmake

@@ -34,7 +34,7 @@ set(ENV{PYTHON_EXECUTABLE} ${PYTHON_EXECUTABLE})
 set(ENV{ARCH}      ${ARCH})
 set(ENV{BOARD_DIR} ${BOARD_DIR})
 set(ENV{SOC_DIR}   ${SOC_DIR})
-set(ENV{PROJECT_BINARY_DIR} ${PROJECT_BINARY_DIR})
+set(ENV{CMAKE_BINARY_DIR} ${CMAKE_BINARY_DIR})
 set(ENV{ARCH_DIR}   ${ARCH_DIR})
 set(ENV{GENERATED_DTS_BOARD_CONF} ${GENERATED_DTS_BOARD_CONF})
 
@@ -65,7 +65,7 @@ foreach(kconfig_target
     ARCH=$ENV{ARCH}
     BOARD_DIR=$ENV{BOARD_DIR}
     SOC_DIR=$ENV{SOC_DIR}
-    PROJECT_BINARY_DIR=$ENV{PROJECT_BINARY_DIR}
+    CMAKE_BINARY_DIR=$ENV{CMAKE_BINARY_DIR}
     ZEPHYR_TOOLCHAIN_VARIANT=${ZEPHYR_TOOLCHAIN_VARIANT}
     ARCH_DIR=$ENV{ARCH_DIR}
     GENERATED_DTS_BOARD_CONF=${GENERATED_DTS_BOARD_CONF}

cmake/zephyr_module.cmake

@@ -37,7 +37,8 @@ endif()
 # Clear the Kconfig.modules generated file in case modules has been removed.
 # The Kconfig.modules contains a list of additional Kconfig files to be sourced
 # based upon <module>/zephyr/module.yml files.
-file(WRITE ${PROJECT_BINARY_DIR}/Kconfig.modules
+set(KCONFIG_MODULES_FILE ${CMAKE_BINARY_DIR}/Kconfig.modules)
+file(WRITE ${KCONFIG_MODULES_FILE}
   "# NOTE: THIS FILE IS AUTOGENERATED BY CMAKE\n"
   )
 # For each west managed project, determine if the project is a zephyr module.
@@ -78,13 +79,13 @@ foreach(module ${west_project_list})
 
     list(APPEND ZEPHYR_MODULES_NAME ${module_name})
     list(APPEND ZEPHYR_MODULES_DIR ${module}/${cmake_subdir})
-    file(APPEND ${PROJECT_BINARY_DIR}/Kconfig.modules ${kconfig_osource})
+    file(APPEND ${KCONFIG_MODULES_FILE} ${kconfig_osource})
   elseif(EXISTS "${module}/${cmake_subdir}/CMakeLists.txt")
     set(kconfig_osource "osource \"${module}/zephyr/Kconfig\"\n")
     get_filename_component(module_name ${module} NAME)
     list(APPEND ZEPHYR_MODULES_NAME ${module_name})
     list(APPEND ZEPHYR_MODULES_DIR ${module}/${cmake_subdir})
-    file(APPEND ${PROJECT_BINARY_DIR}/Kconfig.modules ${kconfig_osource})
+    file(APPEND ${KCONFIG_MODULES_FILE} ${kconfig_osource})
   else()
     # Not a Zephyr module, ignore.
   endif()

doc/CMakeLists.txt

@@ -181,7 +181,7 @@ add_custom_target(
   ARCH_DIR=arch/
   SOC_DIR=soc/
   SRCARCH=x86
-  PROJECT_BINARY_DIR=${CMAKE_CURRENT_BINARY_DIR}
+  CMAKE_BINARY_DIR=${CMAKE_BINARY_DIR}
   KCONFIG_TURBO_MODE=${KCONFIG_TURBO_MODE}
   KCONFIG_DOC_MODE=1
   ${PYTHON_EXECUTABLE} scripts/genrest.py Kconfig ${RST_OUT}/doc/reference/kconfig/