[nrf fromtree] scripts: code_relocate: support section filter

One might want to select the symbols to be relocated inside a file or
a library. To do this, one can use the FILTER argument of
zephyr_code_relocate which must contain a regular expression of the
section names to be selected for relocation.

The test_function_in_sram2 test case in
`tests/application_development/code_relocation` has been updated to
verify that only one function `function_in_sram()` is relocated to ram
and that the function `function_not_relocated()` is not being relocated
when using relocation filter.

Signed-off-by: Sylvain Chouleur <[email protected]>
Signed-off-by: Torsten Rasmussen <[email protected]>
(cherry picked from commit 4454734)

Author: schouleu

cmake/modules/extensions.cmake

@@ -1452,7 +1452,7 @@ endmacro()
 # - PHDR [program_header]: add program header. Used on Xtensa platforms.
 function(zephyr_code_relocate)
   set(options NOCOPY NOKEEP)
-  set(single_args LIBRARY LOCATION PHDR)
+  set(single_args LIBRARY LOCATION PHDR FILTER)
   set(multi_args FILES)
   cmake_parse_arguments(CODE_REL "${options}" "${single_args}"
     "${multi_args}" ${ARGN})
@@ -1529,7 +1529,7 @@ function(zephyr_code_relocate)
     PROPERTY INTERFACE_SOURCES)
   set_property(TARGET code_data_relocation_target
     PROPERTY INTERFACE_SOURCES
-    "${code_rel_str}\n${CODE_REL_LOCATION}:${flag_list}:${file_list}")
+    "${code_rel_str}\n${CODE_REL_LOCATION}:${flag_list}:${file_list},${CODE_REL_FILTER}")
 endfunction()
 
 # Usage:

doc/kernel/code-relocation.rst

@@ -14,15 +14,23 @@ This script provides a robust way to re-order the memory contents without
 actually having to modify the code.  In simple terms this script will do the job
 of ``__attribute__((section("name")))`` for a bunch of files together.
 
+A regular expression filter can be used to select only the required sections to be relocated.
+
 Details
 *******
-The memory region and file are given to the :ref:`gen_relocate_app.py` script in the form of a string.
+The memory region and file are given to the :ref:`gen_relocate_app.py` script
+through a file where each line specifies a list of files to be placed in the
+given region.
+
+An example of such a file is:
+
+  .. code-block:: none
 
-An example of such a string is:
-``SRAM2:/home/xyz/zephyr/samples/hello_world/src/main.c,SRAM1:/home/xyz/zephyr/samples/hello_world/src/main2.c``
+     SRAM2:/home/xyz/zephyr/samples/hello_world/src/main.c,
+     SRAM1:/home/xyz/zephyr/samples/hello_world/src/main2.c,
 
 This script is invoked with the following parameters:
-``python3 gen_relocate_app.py -i input_string -o generated_linker -c generated_code``
+``python3 gen_relocate_app.py -i input_file -o generated_linker -c generated_code``
 
 Kconfig :kconfig:option:`CONFIG_CODE_DATA_RELOCATION` option,  when enabled in
 ``prj.conf``, will invoke the script and do the required relocation.
@@ -97,6 +105,24 @@ This section shows additional configuration options that can be set in
      zephyr_code_relocate(FILES ${sources} LOCATION SRAM)
      zephyr_code_relocate(FILES $<TARGET_PROPERTY:my_tgt,SOURCES> LOCATION SRAM)
 
+Section Filtering
+=================
+
+By default, all sections of the specified files will be relocated. If
+``FILTER`` is used, a regular expression is provided to select only
+the sections to be relocated.
+
+The regular expression applies to sections names which can be used to
+select the file's symbols when this one has been built with
+``-ffunction-sections`` and ``-fdata-sections`` which is the case by
+default.
+
+  .. code-block:: none
+
+     zephyr_code_relocate(FILES src/file1.c FILTER ".*\\.func1|.*\\.func2" LOCATION SRAM2_TEXT)
+
+The example above will only relocate ``func1()`` and ``func2()`` of file ``src/file1.c``
+
 NOKEEP flag
 ===========
 

scripts/build/gen_relocate_app.py

@@ -8,21 +8,22 @@
 """
 This script will relocate .text, .rodata, .data and .bss sections from required files
 and places it in the required memory region. This memory region and file
-are given to this python script in the form of a string.
+are given to this python script in the form of a file.
+A regular expression filter can be applied to select only the required sections from the file.
 
-Example of such a string would be::
+Example of content in such an input file would be::
 
-   SRAM2:COPY:/home/xyz/zephyr/samples/hello_world/src/main.c,\
-   SRAM1:COPY:/home/xyz/zephyr/samples/hello_world/src/main2.c, \
-   FLASH2:NOCOPY:/home/xyz/zephyr/samples/hello_world/src/main3.c
+   SRAM2:COPY:/home/xyz/zephyr/samples/hello_world/src/main.c,.*foo|.*bar
+   SRAM1:COPY:/home/xyz/zephyr/samples/hello_world/src/main2.c,.*bar
+   FLASH2:NOCOPY:/home/xyz/zephyr/samples/hello_world/src/main3.c,
 
 One can also specify the program header for a given memory region:
 
-   SRAM2\\ :phdr0:COPY:/home/xyz/zephyr/samples/hello_world/src/main.c
+   SRAM2\\ :phdr0:COPY:/home/xyz/zephyr/samples/hello_world/src/main.c,
 
 To invoke this script::
 
-   python3 gen_relocate_app.py -i input_string -o generated_linker -c generated_code
+   python3 gen_relocate_app.py -i input_file -o generated_linker -c generated_code
 
 Configuration that needs to be sent to the python script.
 
@@ -45,6 +46,7 @@
 import argparse
 import os
 import glob
+import re
 import warnings
 from collections import defaultdict
 from enum import Enum
@@ -225,7 +227,7 @@ def region_is_default_ram(region_name: str) -> bool:
     return region_name == args.default_ram_region
 
 
-def find_sections(filename: str) -> 'dict[SectionKind, list[OutputSection]]':
+def find_sections(filename: str, symbol_filter: str) -> 'dict[SectionKind, list[OutputSection]]':
     """
     Locate relocatable sections in the given object file.
 
@@ -243,6 +245,9 @@ def find_sections(filename: str) -> 'dict[SectionKind, list[OutputSection]]':
         out = defaultdict(list)
 
         for section in sections:
+            if not re.search(symbol_filter, section.name):
+                # Section is filtered-out
+                continue
             section_kind = SectionKind.for_section_named(section.name)
             if section_kind is None:
                 continue
@@ -501,9 +506,10 @@ def get_obj_filename(searchpath, filename):
 
 
 # Extracts all possible components for the input string:
-# <mem_region>[\ :program_header]:<flag_1>[;<flag_2>...]:<file_1>[;<file_2>...]
-# Returns a 4-tuple with them: (mem_region, program_header, flags, files)
+# <mem_region>[\ :program_header]:<flag_1>[;<flag_2>...]:<file_1>[;<file_2>...][,filter]
+# Returns a 5-tuple with them: (mem_region, program_header, flags, files, filter)
 # If no `program_header` is defined, returns an empty string
+# If no `filter` is defined, returns an empty string
 def parse_input_string(line):
     # Be careful when splitting by : to avoid breaking absolute paths on Windows
     mem_region, rest = line.split(':', 1)
@@ -513,13 +519,19 @@ def parse_input_string(line):
         mem_region = mem_region.rstrip()
         phdr, rest = rest.split(':', 1)
 
-    # Split lists by semicolons, in part to support generator expressions
-    flag_list, file_list = (lst.split(';') for lst in rest.split(':', 1))
+    flag_list, rest = rest.split(':', 1)
+    flag_list = flag_list.split(';')
+
+
+    # Split file list by semicolons, in part to support generator expressions
+    file_list, symbol_filter = rest.split(',', 1)
+    file_list = file_list.split(';')
 
-    return mem_region, phdr, flag_list, file_list
+    return mem_region, phdr, flag_list, file_list, symbol_filter
 
 
-# Create a dict with key as memory type and files as a list of values.
+# Create a dict with key as memory type and (files, symbol_filter) tuple
+# as a list of values.
 # Also, return another dict with program headers for memory regions
 def create_dict_wrt_mem():
     # need to support wild card *
@@ -529,11 +541,12 @@ def create_dict_wrt_mem():
     input_rel_dict = args.input_rel_dict.read().splitlines()
     if not input_rel_dict:
         sys.exit("Disable CONFIG_CODE_DATA_RELOCATION if no file needs relocation")
+
     for line in input_rel_dict:
         if ':' not in line:
             continue
 
-        mem_region, phdr, flag_list, file_list = parse_input_string(line)
+        mem_region, phdr, flag_list, file_list, symbol_filter = parse_input_string(line)
 
         # Handle any program header
         if phdr != '':
@@ -556,12 +569,15 @@ def create_dict_wrt_mem():
         if args.verbose:
             print("Memory region ", mem_region, " Selected for files:", file_name_list)
 
+        # Apply filter on files
+        file_name_filter_list = [(f, symbol_filter) for f in file_name_list]
+
         mem_region = "|".join((mem_region, *flag_list))
 
         if mem_region in rel_dict:
-            rel_dict[mem_region].extend(file_name_list)
+            rel_dict[mem_region].extend(file_name_filter_list)
         else:
-            rel_dict[mem_region] = file_name_list
+            rel_dict[mem_region] = file_name_filter_list
 
     return rel_dict, phdrs
 
@@ -585,13 +601,13 @@ def main():
     for memory_type, files in rel_dict.items():
         full_list_of_sections: 'dict[SectionKind, list[OutputSection]]' = defaultdict(list)
 
-        for filename in files:
+        for filename, symbol_filter in files:
             obj_filename = get_obj_filename(searchpath, filename)
             # the obj file wasn't found. Probably not compiled.
             if not obj_filename:
                 continue
 
-            file_sections = find_sections(obj_filename)
+            file_sections = find_sections(obj_filename, symbol_filter)
             # Merge sections from file into collection of sections for all files
             for category, sections in file_sections.items():
                 full_list_of_sections[category].extend(sections)

tests/application_development/code_relocation/CMakeLists.txt

@@ -17,7 +17,7 @@ endif()
 # Code relocation feature
 zephyr_code_relocate(FILES src/test_file1.c ${SRAM2_PHDR} LOCATION SRAM2)
 
-zephyr_code_relocate(FILES ${CMAKE_CURRENT_SOURCE_DIR}/src/test_file2.c ${RAM_PHDR} LOCATION RAM)
+zephyr_code_relocate(FILES ${CMAKE_CURRENT_SOURCE_DIR}/src/test_file2.c ${RAM_PHDR} LOCATION RAM FILTER ".*sram")
 
 # Add custom library that we can relocate code for
 add_subdirectory(test_lib)

tests/application_development/code_relocation/src/test_file1.c

@@ -23,12 +23,15 @@ __in_section(rodata, sram2, var) const uint32_t var_sram2_rodata = 100U;
 __in_section(custom_section, static, var) uint32_t var_custom_data = 1U;
 
 extern void function_in_sram(int32_t value);
+extern void function_not_relocated(int32_t value);
 void function_in_custom_section(void);
 
 #define HAS_SRAM2_DATA_SECTION (CONFIG_ARM)
 
 ZTEST(code_relocation, test_function_in_sram2)
 {
+	extern uintptr_t __ram_text_reloc_start;
+	extern uintptr_t __ram_text_reloc_end;
 	extern uintptr_t __sram2_text_reloc_start;
 	extern uintptr_t __sram2_text_reloc_end;
 	extern uintptr_t __sram2_data_reloc_start;
@@ -64,7 +67,20 @@ ZTEST(code_relocation, test_function_in_sram2)
 		"var_sram2_bss not in sram2_bss region");
 
 	/* Print values from sram */
+	printk("Address of function_in_sram %p\n", &function_in_sram);
+	zassert_between_inclusive((uintptr_t)&function_in_sram,
+		(uintptr_t)&__ram_text_reloc_start,
+		(uintptr_t)&__ram_text_reloc_end,
+		"function_in_sram is not in ram region");
 	function_in_sram(var_sram2_data);
+
+	/* Print values from non-relocated function */
+	printk("Address of function_not_relocated %p\n", &function_not_relocated);
+	zassert_between_inclusive((uintptr_t)&function_not_relocated,
+		(uintptr_t)&__text_region_start,
+		(uintptr_t)&__text_region_end,
+		"function_not_relocated is not in flash region");
+	function_not_relocated(var_sram2_data);
 	/* Call library function */
 	relocated_library();
 

tests/application_development/code_relocation/src/test_file2.c

@@ -19,3 +19,14 @@ void function_in_sram(int32_t value)
 	printk("Address of memcpy %p\n\n", &memcpy);
 	zassert_mem_equal(src, dst, 8, "memcpy compare error");
 }
+
+void function_not_relocated(int32_t value)
+{
+	char src[8] = "data\n";
+	char dst[8];
+
+	printk("Hello World! %s\n", CONFIG_BOARD);
+	memcpy(dst, src, 8);
+	printk("Address of memcpy %p\n\n", &memcpy);
+	zassert_mem_equal(src, dst, 8, "memcpy compare error");
+}