zephyr/scripts/gen_alignment_script.py

80 lines
2.1 KiB
Python
Executable File

#!/usr/bin/env python3
#
# Copyright (c) 2017 Linaro Limited
#
# SPDX-License-Identifier: Apache-2.0
import sys
import argparse
import pprint
import os
import struct
from distutils.version import LooseVersion
import elftools
from elftools.elf.elffile import ELFFile
from elftools.dwarf import descriptions
from elftools.elf.sections import SymbolTableSection
if LooseVersion(elftools.__version__) < LooseVersion('0.24'):
sys.stderr.write("pyelftools is out of date, need version 0.24 or later\n")
sys.exit(1)
def get_symbols(obj):
for section in obj.iter_sections():
if isinstance(section, SymbolTableSection):
return {sym.name: sym.entry.st_value
for sym in section.iter_symbols()}
raise LookupError("Could not find symbol table")
def parse_args():
global args
parser = argparse.ArgumentParser(
description=__doc__,
formatter_class=argparse.RawDescriptionHelpFormatter)
parser.add_argument(
"-k", "--kernel", required=True,
help="Input zephyr ELF binary")
parser.add_argument(
"-o", "--output", required=True,
help="Output linker file")
parser.add_argument(
"-v", "--verbose", action="store_true",
help="Print extra debugging information")
args = parser.parse_args()
def main():
parse_args()
bit_len = None
with open(args.kernel, "rb") as fp:
elf = ELFFile(fp)
args.little_endian = elf.little_endian
syms = get_symbols(elf)
app_ram_size = syms['__app_last_address_used'] - \
syms['__app_ram_start']
bit_len = app_ram_size.bit_length()
if bit_len:
align_size = 1 << bit_len
else:
align_size = 32
with open(args.output, "w") as fp:
fp.write("/***********************************************\n")
fp.write(" * Generated file, do not modify\n")
fp.write(" **********************************************/\n")
fp.write("_app_data_align = " + str(align_size) + ";\n")
fp.write(". = ALIGN(_app_data_align);\n")
if __name__ == "__main__":
main()