tillitis-key/hw/application_fpga/tools/personalize.py
Joachim Strömbergson 8731908cb1
Support incremental builds for the bitstream.
By patching the UDS and UDI into an already built bitstream, it is now
not necessary to rebuild the entire build flow when changing the UDS
and the UDI. This lowers re-build times significantly.

Signed-off-by: Joachim Strömbergson <joachim@assured.se>
2024-03-20 16:39:45 +01:00

64 lines
2.1 KiB
Python

# -*- coding: utf-8 -*-
#=======================================================================
#
# personalize.py
# --------------
# Python program that patches the UDS and UDI implemented using
# named LUT4 instances to have unique initial values, not the generic
# values used during synthesis, p&r and mapping. This allows us to
# generate device unique bitstreams without running the complete flow.
#
#
# Copyright (C) 2023 Tillitis AB
# Written by Myrtle Shah <gatecat@ds0.me>
# SPDX-License-Identifier: GPL-2.0-only
#
#=======================================================================
import os
def parse_hex(file, length):
data = []
with open(file, "r") as f:
for line in f:
l = line.strip()
if len(l) > 0:
data.append(int(l, 16))
assert len(data) == length, len(data)
return data
def rewrite_lut(lut, idx, data, has_re=False):
# each LUT provides one bit per 32-bit word out of 64/256 bits total
new_init = 0
for i, word in enumerate(data):
if (word >> idx) & 0x1:
# repeat so inputs above address have a don't care value
repeat = (16 // len(data))
for k in range(repeat):
# UDS also has a read enable
# LUT output is zero if this isn't asserted
if has_re and k < (repeat // 2):
continue
new_init |= (1 << (k * len(data) + i))
lut.setParam("LUT_INIT", f"{new_init:016b}")
uds = parse_hex(os.environ["UDS_HEX"], 8)
udi = parse_hex(os.environ["UDI_HEX"], 2)
uds_lut_count = 0
udi_lut_count = 0
for cell_name, cell in ctx.cells:
if "uds_rom_idx" in cell.attrs:
index = int(cell.attrs["uds_rom_idx"], 2)
rewrite_lut(cell, index, uds, True)
uds_lut_count += 1
if "udi_rom_idx" in cell.attrs:
index = int(cell.attrs["udi_rom_idx"], 2)
rewrite_lut(cell, index, udi, False)
udi_lut_count += 1
assert uds_lut_count == 32, uds_lut_count
assert udi_lut_count == 32, udi_lut_count
write_bitstream(ctx, os.environ["OUT_ASC"])