For debugging and dicoverability it is useful to be able to see a list of each event spy in a U-Boot ELF file. Add a script which shows this, along with the event type and the source location. This makes events a little easier to use than weak functions, for example.
Add a basic sandbox test as well. We could provide a test for other boards, but for now, few use events.
Signed-off-by: Simon Glass sjg@chromium.org ---
MAINTAINERS | 2 + scripts/event_dump.py | 117 +++++++++++++++++++++++++++++++ test/py/tests/test_event_dump.py | 19 +++++ 3 files changed, 138 insertions(+) create mode 100755 scripts/event_dump.py create mode 100644 test/py/tests/test_event_dump.py
diff --git a/MAINTAINERS b/MAINTAINERS index 117a7d6c985..c040fb83162 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -792,7 +792,9 @@ S: Maintained F: cmd/event.c F: common/event.c F: include/event.h +F: scripts/event_dump.py F: test/common/event.c +F: test/py/tests/test_event_dump.py
FASTBOOT S: Orphaned diff --git a/scripts/event_dump.py b/scripts/event_dump.py new file mode 100755 index 00000000000..ce006ae31d1 --- /dev/null +++ b/scripts/event_dump.py @@ -0,0 +1,117 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0+ +# Copyright 2020 Google LLC +# Written by Simon Glass sjg@chromium.org + +"""Decode the evspy_info linker list in a U-Boot ELF image""" + +from argparse import ArgumentParser +import os +import re +import struct +import sys + +our_path = os.path.dirname(os.path.realpath(__file__)) +src_path = os.path.dirname(our_path) + +sys.path.insert(1, os.path.join(our_path, '../tools')) + +from binman import elf +from patman import tools + +PREFIX = '_u_boot_list_2_evspy_info_2_' +RE_EVTYPE = re.compile('%s(.*)' % PREFIX) + +def show_sym(fname, data, endian, evtype, sym): + """Show information about an evspy entry + + Args: + fname (str): Filename of ELF file + data (bytes): Data for this symbol + endian (str): Endianness to use ('little', 'big', 'auto') + evtype (str): Event type, e.g. 'MISC_INIT_F' + sym (elf.Symbol): Symbol to show + """ + def _unpack_val(sym_data, offset): + start = offset * func_size + val_data = sym_data[start:start + func_size] + fmt = '%s%s' % ('>' if endian == 'big' else '<', + 'L' if func_size == 4 else 'Q') + val = struct.unpack(fmt, val_data)[0] + return val + + # Get the data, which is a struct evspy_info + sym_data = data[sym.offset:sym.offset + sym.size] + + # Figure out the word size of the struct + func_size = 4 if sym.size < 16 else 8 + + # Read the function name for evspy_info->func + while True: + # Switch to big-endian if we see a failure + func_addr = _unpack_val(sym_data, 0) + func_name = elf.GetSymbolFromAddress(fname, func_addr) + if not func_name and endian == 'auto': + endian = 'big' + else: + break + has_id = sym.size in [12, 24] + if has_id: + # Find the address of evspy_info->id in the ELF + id_addr = _unpack_val(sym_data, 2) + + # Get the file offset for that address + id_ofs = elf.GetFileOffset(fname, id_addr) + + # Read out a nul-terminated string + id_data = data[id_ofs:id_ofs + 80] + pos = id_data.find(0) + if pos: + id_data = id_data[:pos] + id_str = id_data.decode('utf-8') + else: + id_str = None + + # Find the file/line for the function + cmd = ['addr2line', '-e', fname, '%x' % func_addr] + out = tools.Run(*cmd).strip() + + # Drop the full path if it is the current directory + if out.startswith(src_path): + out = out[len(src_path) + 1:] + print('%-20s %-30s %s' % (evtype, id_str or f'f:{func_name}', out)) + +def show_event_spy_list(fname, endian): + """Show a the event-spy- list from a U-Boot image + + Args: + fname (str): Filename of ELF file + endian (str): Endianness to use ('little', 'big', 'auto') + """ + syms = elf.GetSymbolFileOffset(fname, [PREFIX]) + data = tools.ReadFile(fname) + print('%-20s %-30s %s' % ('Event type', 'Id', 'Source location')) + print('%-20s %-30s %s' % ('-' * 20, '-' * 30, '-' * 30)) + for name, sym in syms.items(): + m_evtype = RE_EVTYPE.search(name) + evtype = m_evtype .group(1) + show_sym(fname, data, endian, evtype, sym) + +def main(argv): + """Main program + + Args: + argv (list of str): List of program arguments, excluding arvg[0] + """ + epilog = 'Show a list of even spies in a U-Boot EFL file' + parser = ArgumentParser(epilog=epilog) + parser.add_argument('elf', type=str, help='ELF file to decode') + parser.add_argument('-e', '--endian', type=str, default='auto', + help='Big-endian image') + parser.add_argument('-t', '--test', action='store_true', + help='Big-endian image') + args = parser.parse_args(argv) + show_event_spy_list(args.elf, args.endian) + +if __name__ == "__main__": + main(sys.argv[1:]) diff --git a/test/py/tests/test_event_dump.py b/test/py/tests/test_event_dump.py new file mode 100644 index 00000000000..6a5ea42a60a --- /dev/null +++ b/test/py/tests/test_event_dump.py @@ -0,0 +1,19 @@ +# SPDX-License-Identifier: GPL-2.0+ +# Copyright 2021 Google LLC +# Written by Simon Glass sjg@chromium.org + +import pytest +import u_boot_utils as util + +# This is only a partial test - coverting 64-bit sandbox. It does not test +# big-endian images, nor 32-bit images +@pytest.mark.boardspec('sandbox') +def test_event_dump(u_boot_console): + """Test that the "help" command can be executed.""" + cons = u_boot_console + sandbox = cons.config.build_dir + '/u-boot' + out = util.run_and_log(cons, ['scripts/event_dump.py', sandbox]) + expect = '''Event type Id Source location +-------------------- ------------------------------ ------------------------------ +EVT_MISC_INIT_F sandbox_misc_init_f arch/sandbox/cpu/start.c:''' + assert out[:len(expect)] == expect