device: export CMake pre-load from device subsystem enumeration script

Extend the device subsystem enumeration script to produce a CMake
pre-load script.

This allow CMake linker generator scripts to create iterable sections
based on output from device subsystem enumeration.

This ensures that same functionality is available in both ld linker
templates and the linker generator.

Update linker generators to support the use of the device subsystem
enumeration CMake pre-load script.

Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>

CMakeLists.txt

@@ -889,21 +889,30 @@ set(
   ${CMAKE_CURRENT_BINARY_DIR}/include/generated/device-api-sections.ld
   )
 
+set(DEVICE_API_LINKER_SECTIONS_CMAKE
+    ${CMAKE_CURRENT_BINARY_DIR}/include/generated/device-api-sections.cmake
+)
+
 add_custom_command(
-  OUTPUT ${DEVICE_API_LD_SECTIONS}
+  OUTPUT ${DEVICE_API_LD_SECTIONS} ${DEVICE_API_LINKER_SECTIONS_CMAKE}
   COMMAND
     ${PYTHON_EXECUTABLE}
     ${ZEPHYR_BASE}/scripts/build/gen_iter_sections.py
+    --alignment ${CONFIG_LINKER_ITERABLE_SUBALIGN}
     --input ${struct_tags_json}
     --tag __subsystem
     --ld-output ${DEVICE_API_LD_SECTIONS}
+    --cmake-output ${DEVICE_API_LINKER_SECTIONS_CMAKE}
   DEPENDS
     ${ZEPHYR_BASE}/scripts/build/gen_iter_sections.py
     ${struct_tags_json}
   WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
   )
 
-add_custom_target(${DEVICE_API_LD_TARGET} DEPENDS ${DEVICE_API_LD_SECTIONS})
+add_custom_target(${DEVICE_API_LD_TARGET}
+                  DEPENDS ${DEVICE_API_LD_SECTIONS}
+                          ${DEVICE_API_LINKER_SECTIONS_CMAKE}
+)
 
 # Add a pseudo-target that is up-to-date when all generated headers
 # are up-to-date.

cmake/linker/armlink/target.cmake

@@ -44,12 +44,14 @@ macro(configure_linker_script linker_script_gen linker_pass_define)
            ${STEERING_FILE}
            ${STEERING_C}
     COMMAND ${CMAKE_COMMAND}
+      -C ${DEVICE_API_LINKER_SECTIONS_CMAKE}
       -C ${cmake_linker_script_settings}
       -DPASS="${linker_pass_define}"
       ${STEERING_FILE_ARG}
       ${STEERING_C_ARG}
       -DOUT_FILE=${CMAKE_CURRENT_BINARY_DIR}/${linker_script_gen}
       -P ${ZEPHYR_BASE}/cmake/linker/armlink/scatter_script.cmake
+    DEPENDS ${DEVICE_API_LD_TARGET}
   )
 
   if("LINKER_ZEPHYR_FINAL" IN_LIST linker_pass_define_list)

cmake/linker/ld/target.cmake

@@ -36,10 +36,12 @@ macro(configure_linker_script linker_script_gen linker_pass_define)
     add_custom_command(
       OUTPUT ${linker_script_gen}
       COMMAND ${CMAKE_COMMAND}
+        -C ${DEVICE_API_LINKER_SECTIONS_CMAKE}
         -C ${cmake_linker_script_settings}
         -DPASS="${linker_pass_define}"
         -DOUT_FILE=${CMAKE_CURRENT_BINARY_DIR}/${linker_script_gen}
         -P ${ZEPHYR_BASE}/cmake/linker/ld/ld_script.cmake
+      DEPENDS ${DEVICE_API_LD_TARGET}
     )
   else()
     set(template_script_defines ${linker_pass_define})

cmake/linker/linker_script_common.cmake

@@ -132,7 +132,7 @@ function(create_section)
   set(INDEX 100)
   set(settings_single "ALIGN;ANY;FIRST;KEEP;OFFSET;PRIO;SECTION;SORT")
   set(settings_multi  "FLAGS;INPUT;PASS;SYMBOLS")
-  foreach(settings ${SECTION_SETTINGS})
+  foreach(settings ${SECTION_SETTINGS} ${DEVICE_API_SECTION_SETTINGS})
     if("${settings}" MATCHES "^{(.*)}$")
       cmake_parse_arguments(SETTINGS "" "${settings_single}" "${settings_multi}" ${CMAKE_MATCH_1})
 
@@ -652,7 +652,7 @@ foreach(group ${GROUPS})
   endif()
 endforeach()
 
-foreach(section ${SECTIONS})
+foreach(section ${SECTIONS} ${DEVICE_API_SECTIONS})
   if("${section}" MATCHES "^{(.*)}$")
     create_section(${CMAKE_MATCH_1} SYSTEM ${new_system})
   endif()

scripts/build/gen_iter_sections.py

@@ -16,10 +16,30 @@ def get_tagged_items(filepath: str, tag: str) -> list:
         return json.load(fp)[tag]
 
 
-def gen_ld(filepath: str, items: list):
+def gen_ld(filepath: str, items: list, alignment: int):
     with open(filepath, "w") as fp:
         for item in items:
-            fp.write(f"ITERABLE_SECTION_ROM({item}, Z_LINK_ITERABLE_SUBALIGN)\n")
+            fp.write(f"ITERABLE_SECTION_ROM({item}, {alignment})\n")
+
+
+def gen_cmake(filepath: str, items: list, alignment: int):
+    with open(filepath, "w") as fp:
+        for item in items:
+            fp.write(
+                f'list(APPEND sections "{{NAME\\;{item}_area\\;'
+                + 'GROUP\\;RODATA_REGION\\;'
+                + f'SUBALIGN\\;{alignment}\\;'
+                + 'NOINPUT\\;TRUE}")\n'
+            )
+            fp.write(
+                f'list(APPEND section_settings "{{SECTION\\;{item}_area\\;'
+                + 'SORT\\;NAME\\;'
+                + 'KEEP\\;TRUE\\;'
+                + f'INPUT\\;._{item}.static.*\\;'
+                + f'SYMBOLS\\;_{item}_list_start\\;_{item}_list_end}}")\n'
+            )
+        fp.write('set(DEVICE_API_SECTIONS         "${sections}" CACHE INTERNAL "")\n')
+        fp.write('set(DEVICE_API_SECTION_SETTINGS "${section_settings}" CACHE INTERNAL "")\n')
 
 
 def parse_args() -> argparse.Namespace:
@@ -30,8 +50,12 @@ def parse_args() -> argparse.Namespace:
     )
 
     parser.add_argument("-i", "--input", required=True, help="Path to input list of tags")
+    parser.add_argument("-a", "--alignment", required=True, help="Iterable section alignment")
     parser.add_argument("-t", "--tag", required=True, help="Tag to generate iterable sections for")
     parser.add_argument("-l", "--ld-output", required=True, help="Path to output linker file")
+    parser.add_argument(
+        "-c", "--cmake-output", required=True, help="Path to CMake linker script inclusion file"
+    )
 
     return parser.parse_args()
 
@@ -41,7 +65,8 @@ def main():
 
     items = get_tagged_items(args.input, args.tag)
 
-    gen_ld(args.ld_output, items)
+    gen_ld(args.ld_output, items, args.alignment)
+    gen_cmake(args.cmake_output, items, args.alignment)
 
 
 if __name__ == "__main__":