cmake: Fix the generation of fixup files

A recent change in how the fixup mechanism works caused several
regressions. See
zephyrproject-rtos#12680 for more
details about the regressions.

The core of the matter is that using defines to pass on include paths
causes interopability issues when integrating with external build
systems.

To resolve this we re-write the fixup mechanism to instead generate an
aggregated fixup file that is ready to be included at build time. Then
no paths are passed through defines and we resolve the regressions
reported.

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

Author: SebastianBoe

CMakeLists.txt

@@ -487,32 +487,21 @@ endforeach()
 set_ifndef(  DTS_BOARD_FIXUP_FILE                                   ${BOARD_DIR}/dts_fixup.h)
 set_ifndef(    DTS_SOC_FIXUP_FILE                 ${SOC_DIR}/${ARCH}/${SOC_PATH}/dts_fixup.h)
 set(           DTS_APP_FIXUP_FILE                      ${APPLICATION_SOURCE_DIR}/dts_fixup.h)
-set_ifndef(DTS_SHIELDS_FIXUP_FILE ${ZEPHYR_BINARY_DIR}/include/generated/shields/dts_fixup.h)
 
-# Concatenate the shield fixups into a single file for easy
-# #include'ing
-foreach(f ${shield_dts_fixups})
-  if(EXISTS ${f})
-	file(READ ${f} contents)
-	file(APPEND ${DTS_SHIELDS_FIXUP_FILE} "${contents}")
-  endif()
-endforeach()
+set_ifndef(DTS_CAT_OF_FIXUP_FILES ${ZEPHYR_BINARY_DIR}/include/generated/generated_dts_board_fixups.h)
 
-foreach(fixup_source
-      DTS_BOARD_FIXUP_FILE
-        DTS_SOC_FIXUP_FILE
-        DTS_APP_FIXUP_FILE
-	DTS_SHIELDS_FIXUP_FILE
+# Concatenate the fixups into a single header file for easy
+# #include'ing
+file(WRITE ${DTS_CAT_OF_FIXUP_FILES} "/* May only be included by generated_dts_board.h */\n\n")
+foreach(fixup_file
+      ${DTS_BOARD_FIXUP_FILE}
+      ${DTS_SOC_FIXUP_FILE}
+      ${DTS_APP_FIXUP_FILE}
+      ${shield_dts_fixups}
 	)
-  if(EXISTS ${${fixup_source}})
-	# Add defines such that generated_dts_board.h knows which fixups
-	# are present and where they
-	# are. e.g. -DDTS_SOC_FIXUP_FILE=/path/to/fixup.h
-	zephyr_compile_definitions(${fixup_source}="${${fixup_source}}")
-	set_property(GLOBAL APPEND PROPERTY
-	  PROPERTY_LINKER_SCRIPT_DEFINES
-	  -D${fixup_source}="${${fixup_source}}"
-	  )
+  if(EXISTS ${fixup_file})
+	file(READ ${fixup_file} contents)
+	file(APPEND ${DTS_CAT_OF_FIXUP_FILES} "${contents}")
   endif()
 endforeach()
 

include/generated_dts_board.h

@@ -15,20 +15,6 @@
 
 /* The following definitions fixup the generated include */
 
-#ifdef DTS_BOARD_FIXUP_FILE
-#include DTS_BOARD_FIXUP_FILE
-#endif
-
-#ifdef DTS_SOC_FIXUP_FILE
-#include DTS_SOC_FIXUP_FILE
-#endif
-
-#ifdef DTS_APP_FIXUP_FILE
-#include DTS_APP_FIXUP_FILE
-#endif
-
-#ifdef DTS_SHIELDS_FIXUP_FILE
-#include DTS_SHIELDS_FIXUP_FILE
-#endif
+#include <generated_dts_board_fixups.h>
 
 #endif /* GENERATED_DTS_BOARD_H */