cmake: dts: import devicetree symbols into CMake

This commit introduces devicetree API in CMake so that devicetree
properties and register block can be used in the CMake build system.

The script scripts/dts/gen_dts_cmake.py processes the edt.pickle and
generates a corresponding devicetree property map in a devicetree_target
that is then used in CMake.

The following devicetree API has been made available in Zephyr CMake:
- dt_nodelabel(<var> NODELABEL <label>)
- dt_node_exists(<var> PATH <path>)
- dt_node_has_status(<var> PATH <path> STATUS <status>)
- dt_prop(<var> PATH <path> PROPERTY <prop>)
- dt_prop(<var> PATH <path> INDEX <idx> PROPERTY <prop>)
- dt_num_regs(<var> PATH <path>)
- dt_reg_addr(<var> PATH <path> [INDEX <idx>])
- dt_reg_size(<var> PATH <path> [INDEX <idx>])
- dt_has_chosen(<var> PROPERTY <prop>)
- dt_chosen(<var> PROPERTY <prop>)

Signed-off-by: Martí Bolívar <[email protected]>
Signed-off-by: Torsten Rasmussen <[email protected]>

cmake/dts.cmake

@@ -27,6 +27,10 @@ set(DTS_POST_CPP                ${PROJECT_BINARY_DIR}/${BOARD}.dts.pre.tmp)
 # This is relative to each element of DTS_ROOT.
 set(VENDOR_PREFIXES             dts/bindings/vendor-prefixes.txt)
 
+# Devicetree in CMake.
+set(DTS_CMAKE_SCRIPT            ${ZEPHYR_BASE}/scripts/dts/gen_dts_cmake.py)
+set(DTS_CMAKE                   ${PROJECT_BINARY_DIR}/dts.cmake)
+
 set_ifndef(DTS_SOURCE ${BOARD_DIR}/${BOARD}.dts)
 
 zephyr_file(APPLICATION_ROOT DTS_ROOT)
@@ -175,6 +179,7 @@ if(SUPPORTS_DTS)
     CMAKE_CONFIGURE_DEPENDS
     ${include_files}
     ${GEN_DEFINES_SCRIPT}
+    ${DTS_CMAKE_SCRIPT}
     )
 
   #
@@ -250,6 +255,20 @@ if(SUPPORTS_DTS)
     message(STATUS "Generated device_extern.h: ${DEVICE_EXTERN_H}")
   endif()
 
+  execute_process(
+    COMMAND ${PYTHON_EXECUTABLE} ${DTS_CMAKE_SCRIPT}
+    --edt-pickle ${EDT_PICKLE}
+    --cmake-out ${DTS_CMAKE}
+    WORKING_DIRECTORY ${PROJECT_BINARY_DIR}
+    RESULT_VARIABLE ret
+    )
+  if(NOT "${ret}" STREQUAL "0")
+    message(FATAL_ERROR "gen_dts_cmake.py failed with return code: ${ret}")
+  else()
+    message(STATUS "Including generated dts.cmake file: ${DTS_CMAKE}")
+    include(${DTS_CMAKE})
+  endif()
+
 else()
   file(WRITE ${DEVICETREE_UNFIXED_H} "/* WARNING. THIS FILE IS AUTO-GENERATED. DO NOT MODIFY! */")
   file(WRITE ${DEVICE_EXTERN_H} "/* WARNING. THIS FILE IS AUTO-GENERATED. DO NOT MODIFY! */")