software/demo: Add --mem parameter to allow specifying Memory region where code will be loaded/executed.

litex/soc/software/demo/demo.py

@@ -3,16 +3,19 @@
 #
 # This file is part of LiteX.
 #
-# Copyright (c) 2020 Florent Kermarrec <florent@enjoy-digital.fr>
+# Copyright (c) 2020-2022 Florent Kermarrec <florent@enjoy-digital.fr>
 # SPDX-License-Identifier: BSD-2-Clause
 
 import os
 import argparse
 
+from litex.build.tools import replace_in_file
+
 def main():
     parser = argparse.ArgumentParser(description="LiteX Bare Metal Demo App.")
     parser.add_argument("--build-path",                      help="Target's build path (ex build/board_name).", required=True)
     parser.add_argument("--with-cxx",   action="store_true", help="Enable CXX support.")
+    parser.add_argument("--mem",        default="main_ram",  help="Memory Region from which code will be executed.")
     args = parser.parse_args()
 
     # Create demo directory
@@ -21,6 +24,9 @@ def main():
     # Copy contents to demo directory
     os.system(f"cp {os.path.abspath(os.path.dirname(__file__))}/* demo")
 
+    # Update memory region.
+    replace_in_file("demo/linker.ld", "main_ram", args.mem)
+
     # Compile demo
     build_path = args.build_path if os.path.isabs(args.build_path) else os.path.join("..", args.build_path)
     os.system(f"export BUILD_DIR={build_path} && {'export WITH_CXX=1 &&' if args.with_cxx else ''} cd demo && make")