summaryrefslogtreecommitdiffstatshomepage
path: root/tools/mpy_ld.py
diff options
context:
space:
mode:
Diffstat (limited to 'tools/mpy_ld.py')
-rwxr-xr-xtools/mpy_ld.py82
1 files changed, 78 insertions, 4 deletions
diff --git a/tools/mpy_ld.py b/tools/mpy_ld.py
index a47653f900..6518037f2e 100755
--- a/tools/mpy_ld.py
+++ b/tools/mpy_ld.py
@@ -402,6 +402,7 @@ class LinkEnv:
self.known_syms = {} # dict of symbols that are defined
self.unresolved_syms = [] # list of unresolved symbols
self.mpy_relocs = [] # list of relocations needed in the output .mpy file
+ self.externs = {} # dict of externally-defined symbols
def check_arch(self, arch_name):
if arch_name != self.arch.name:
@@ -491,10 +492,14 @@ def populate_got(env):
sym = got_entry.sym
if hasattr(sym, "resolved"):
sym = sym.resolved
- sec = sym.section
- addr = sym["st_value"]
- got_entry.sec_name = sec.name
- got_entry.link_addr += sec.addr + addr
+ if sym.name in env.externs:
+ got_entry.sec_name = ".external.fixed_addr"
+ got_entry.link_addr = env.externs[sym.name]
+ else:
+ sec = sym.section
+ addr = sym["st_value"]
+ got_entry.sec_name = sec.name
+ got_entry.link_addr += sec.addr + addr
# Get sorted GOT, sorted by external, text, rodata, bss so relocations can be combined
got_list = sorted(
@@ -520,6 +525,9 @@ def populate_got(env):
dest = int(got_entry.name.split("+")[1], 16) // env.arch.word_size
elif got_entry.sec_name == ".external.mp_fun_table":
dest = got_entry.sym.mp_fun_table_offset
+ elif got_entry.sec_name == ".external.fixed_addr":
+ # Fixed-address symbols should not be relocated.
+ continue
elif got_entry.sec_name.startswith(".text"):
dest = ".text"
elif got_entry.sec_name.startswith(".rodata"):
@@ -1207,6 +1215,9 @@ def link_objects(env, native_qstr_vals_len):
sym.section = env.obj_table_section
elif sym.name in env.known_syms:
sym.resolved = env.known_syms[sym.name]
+ elif sym.name in env.externs:
+ # Fixed-address symbols do not need pre-processing.
+ continue
else:
if sym.name in fun_table:
sym.section = mp_fun_table_sec
@@ -1214,6 +1225,15 @@ def link_objects(env, native_qstr_vals_len):
else:
undef_errors.append("{}: undefined symbol: {}".format(sym.filename, sym.name))
+ for sym in env.externs:
+ if sym in env.known_syms:
+ log(
+ LOG_LEVEL_1,
+ "Symbol {} is a fixed-address symbol at {:08x} and is also provided from an object file".format(
+ sym, env.externs[sym]
+ ),
+ )
+
if undef_errors:
raise LinkError("\n".join(undef_errors))
@@ -1456,6 +1476,9 @@ def do_link(args):
log(LOG_LEVEL_2, "qstr vals: " + ", ".join(native_qstr_vals))
env = LinkEnv(args.arch)
try:
+ if args.externs:
+ env.externs = parse_linkerscript(args.externs)
+
# Load object files
for fn in args.files:
with open(fn, "rb") as f:
@@ -1484,6 +1507,50 @@ def do_link(args):
sys.exit(1)
+def parse_linkerscript(source):
+ # This extracts fixed-address symbol lists from linkerscripts, only parsing
+ # a small subset of all possible directives. Right now the only
+ # linkerscript file this is really tested against is the ESP8266's builtin
+ # ROM functions list ($SDK/ld/eagle.rom.addr.v6.ld).
+ #
+ # The parser should be able to handle symbol entries inside ESP-IDF's ROM
+ # symbol lists for the ESP32 range of MCUs as well (see *.ld files in
+ # $SDK/components/esp_rom/<name>/).
+
+ symbols = {}
+
+ LINE_REGEX = re.compile(
+ r'^(?P<weak>PROVIDE\()?' # optional weak marker start
+ r'(?P<symbol>[a-zA-Z_]\w*)' # symbol name
+ r'=0x(?P<address>[\da-fA-F]{1,8})*' # symbol address
+ r'(?(weak)\));$', # optional weak marker end and line terminator
+ re.ASCII,
+ )
+
+ inside_comment = False
+ for line in (line.strip() for line in source.readlines()):
+ if line.startswith('/*') and not inside_comment:
+ if not line.endswith('*/'):
+ inside_comment = True
+ continue
+ if inside_comment:
+ if line.endswith('*/'):
+ inside_comment = False
+ continue
+ if line.startswith('//'):
+ continue
+ match = LINE_REGEX.match(''.join(line.split()))
+ if not match:
+ continue
+ tokens = match.groupdict()
+ symbol = tokens['symbol']
+ address = int(tokens['address'], 16)
+ if symbol in symbols:
+ raise ValueError(f"Symbol {symbol} already defined")
+ symbols[symbol] = address
+ return symbols
+
+
def main():
import argparse
@@ -1500,6 +1567,13 @@ def main():
cmd_parser.add_argument(
"--output", "-o", default=None, help="output .mpy file (default to input with .o->.mpy)"
)
+ cmd_parser.add_argument(
+ "--externs",
+ "-e",
+ type=argparse.FileType("rt"),
+ default=None,
+ help="linkerscript providing fixed-address symbols to augment symbol resolution",
+ )
cmd_parser.add_argument("files", nargs="+", help="input files")
args = cmd_parser.parse_args()