Prusa-Firmware/tools/elf_mem_map
2021-07-30 06:38:12 +02:00

154 lines
4.8 KiB
Python
Executable File

#!/usr/bin/env python3
import argparse
import elftools.elf.elffile
import elftools.dwarf.descriptions
from struct import unpack
SRAM_OFFSET = 0x800000
EEPROM_OFFSET = 0x810000
FILL_BYTE = b'\0'
def get_elf_globals(path):
fd = open(path, "rb")
if fd is None:
return
elffile = elftools.elf.elffile.ELFFile(fd)
if elffile is None or not elffile.has_dwarf_info():
return
# probably not needed, since we're decoding expressions manually
elftools.dwarf.descriptions.set_global_machine_arch(elffile.get_machine_arch())
dwarfinfo = elffile.get_dwarf_info()
grefs = []
for CU in dwarfinfo.iter_CUs():
for DIE in CU.iter_DIEs():
# handle only variable types
if DIE.tag != 'DW_TAG_variable':
continue
if 'DW_AT_name' not in DIE.attributes:
continue
if 'DW_AT_location' not in DIE.attributes:
continue
if 'DW_AT_type' not in DIE.attributes:
continue
# handle locations encoded directly as DW_OP_addr (leaf globals)
at_loc = DIE.attributes['DW_AT_location']
if at_loc.form != 'DW_FORM_block1' or at_loc.value[0] != 3:
continue
loc = (at_loc.value[1]) + (at_loc.value[2] << 8) \
+ (at_loc.value[3] << 16) + (at_loc.value[4] << 24)
if loc < SRAM_OFFSET or loc >= EEPROM_OFFSET:
continue
loc -= SRAM_OFFSET
# variable name
name = DIE.attributes['DW_AT_name'].value.decode('ascii')
# recurse on type to find the leaf definition
type_DIE = DIE
while 'DW_AT_type' in type_DIE.attributes:
type_DIE = type_DIE.get_DIE_from_attribute('DW_AT_type')
byte_size = type_DIE.attributes.get('DW_AT_byte_size')
if byte_size is None:
continue
size = byte_size.value
grefs.append([name, loc, size])
return grefs
def decode_dump(path):
fd = open(path, 'r')
if fd is None:
return None
buf_addr = None # starting address
buf_data = None # data
for line in fd:
tokens = line.split(maxsplit=1)
if len(tokens) == 0 or tokens[0] == 'ok':
break
elif len(tokens) < 2 or tokens[0] == 'D2':
continue
addr = int.from_bytes(bytes.fromhex(tokens[0]), 'big')
data = bytes.fromhex(tokens[1])
if buf_addr is None:
buf_addr = addr
buf_data = data
else:
# grow buffer as needed
if addr < buf_addr:
buf_data = FILL_BYTE * (buf_addr - addr)
buf_addr = addr
addr_end = addr + len(data)
buf_end = buf_addr + len(buf_data)
if addr_end > buf_end:
buf_data += FILL_BYTE * (addr_end - buf_end)
# replace new part
rep_start = addr - buf_addr
rep_end = rep_start + len(data)
buf_data = buf_data[:rep_start] + data + buf_data[rep_end:]
return (buf_addr, buf_data)
def annotate_refs(grefs, addr, data, width=45):
for name, loc, size in grefs:
if loc < addr:
continue
if loc + size > addr + len(data):
continue
pos = loc-addr
buf = data[pos:pos+size]
buf_repr = ''
if len(buf) in [1, 2, 4]:
# attempt to decode as integers
buf_repr += ' I:' + str(int.from_bytes(buf, 'big')).rjust(10)
if len(buf) in [4, 8]:
# attempt to decode as floats
buf_repr += ' F:' + '{:10.3f}'.format(unpack('f', buf)[0])
print('{:04x} {} {:4}{} R:{}'.format(loc, name.ljust(width), size,
buf_repr, buf.hex()))
def print_map(grefs):
print('OFFSET\tSIZE\tNAME')
for name, loc, size in grefs:
print('{:x}\t{}\t{}'.format(loc, size, name))
def main():
ap = argparse.ArgumentParser(description="""
Generate a symbol table map starting directly from an ELF
firmware with DWARF2 debugging information.
When used along with a memory dump obtained from the D2 g-code,
show the value of each symbol which is within the address range.
""")
ap.add_argument('elf', help='ELF file containing DWARF2 debugging information')
g = ap.add_mutually_exclusive_group(required=True)
g.add_argument('dump', nargs='?', help='RAM dump obtained from D2 g-code')
g.add_argument('--map', action='store_true', help='dump global memory map')
args = ap.parse_args()
grefs = get_elf_globals(args.elf)
grefs = list(sorted(grefs, key=lambda x: x[1]))
if args.dump is None:
print_map(grefs)
else:
addr, data = decode_dump(args.dump)
annotate_refs(grefs, addr, data)
if __name__ == '__main__':
exit(main())