Build: Enable code sharing between bootloader and SPE
Add CMake functions to allow sharing regions of code between
independently linked binaries.
Signed-off-by: Tamas Ban <tamas.ban@arm.com>
Change-Id: I6a6132d6c1558b242d8da1dedab14f93a852f81a
diff --git a/cmake/Common/WeakenSymbols.cmake b/cmake/Common/WeakenSymbols.cmake
new file mode 100644
index 0000000..0ae53d3
--- /dev/null
+++ b/cmake/Common/WeakenSymbols.cmake
@@ -0,0 +1,77 @@
+#-------------------------------------------------------------------------------
+# Copyright (c) 2020, Arm Limited. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+#-------------------------------------------------------------------------------
+
+# A CMake script to weaken identical symbols in the target linked libraries to avoid
+# symbol collision at linking time between shared code and other libraries.
+# i.e.: Shared cryptographic code between MCUBoot and secure runtime firmware.
+#
+# INPUT parameters:
+# LIB_LIST - List of all libraries which are linked to the target, and are using
+# the shared code.
+# SHARED_CODE_PATH - The location of the shared code. It could be outside of TF-M repository.
+#
+# OUTPUTS produced by this script:
+# The libraries might be modified by this script, if they contain the same symbols
+# as the shared code.
+
+# TODO: Library search path is modified manually to include path for platform
+# related libraries.
+
+find_program(OBJCOPY arm-none-eabi-objcopy)
+if (OBJCOPY STREQUAL "OBJCOPY-NOTFOUND")
+ message(FATAL_ERROR "WeakenSymbols.cmake: mandatory tool 'arm-none-eabi-objcopy' is missing.")
+endif()
+
+# Macro to collect all libraries where an *.a file is found
+macro(LIBRARY_DIRECTORIES return_list)
+ file(GLOB_RECURSE new_list *.a)
+ set(dir_list "")
+ foreach(file_path ${new_list})
+ get_filename_component(dir_path ${file_path} PATH)
+ set(dir_list ${dir_list} ${dir_path})
+ endforeach()
+ list(REMOVE_DUPLICATES dir_list)
+ set(${return_list} ${dir_list})
+endmacro()
+
+# Create a library search path for static libraries
+LIBRARY_DIRECTORIES(LIBRARY_PATH)
+
+# Workaround to include directories outside of 'secure_fw' folder for platform
+list(APPEND LIBRARY_PATH ${CMAKE_CURRENT_BINARY_DIR}/../platform/ext/accelerator/cc312/crypto_service_cc312 # Musca-B1: libcrypto_service_cc312.a
+ ${CMAKE_CURRENT_BINARY_DIR}/../platform/ext/accelerator
+ ${CMAKE_CURRENT_BINARY_DIR}/../platform
+)
+
+# When invoking the CMake scripts the original list separator(;) is replaced with space.
+# Need to convert back to be able to handle as a list.
+string(REPLACE " " ";" _LIB_LIST ${LIB_LIST})
+
+# Want to weaken all shared symbols in one go, so first concatenate them.
+# There are libraries which might not contain any of these, but it does
+# not cause any issue, the command does not return with error code.
+file(STRINGS ${SHARED_CODE_PATH}/shared_symbols_name.txt SHARED_SYMBOL_NAME)
+foreach(_SYMBOL IN LISTS SHARED_SYMBOL_NAME)
+ list(APPEND ARGUMENT "-W${_SYMBOL}")
+endforeach()
+
+# Iterate over each library and set potentially colliding symbols to be weak
+foreach(LIB IN LISTS _LIB_LIST)
+ find_file(LIB_FULL_PATH "lib${LIB}.a" PATHS ${LIBRARY_PATH} PATH_SUFFIXES Common NO_DEFAULT_PATH)
+ if (NOT ${LIB_FULL_PATH} STREQUAL "LIB_FULL_PATH-NOTFOUND")
+ execute_process(COMMAND ${OBJCOPY} ${ARGUMENT} ${LIB_FULL_PATH}
+ TIMEOUT 120
+ OUTPUT_VARIABLE _RES
+ ERROR_VARIABLE _RES
+ RESULT_VARIABLE _STATUS_CODE
+ OUTPUT_STRIP_TRAILING_WHITESPACE)
+ if (_STATUS_CODE GREATER 0)
+ message(FATAL_ERROR "ERROR: Failed to execute ${OBJCOPY} ${_RES}")
+ endif()
+ endif()
+ unset(LIB_FULL_PATH CACHE)
+endforeach()