Add flake8 lint CI Job

.github/workflows/build_test.yaml

@@ -3,6 +3,7 @@
 # QEMU OpenTitan CI
 #
 # Copyright (c) 2023-2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache License 2.0
 #------------------------------------------------------------------------------
 
@@ -86,18 +87,20 @@ jobs:
   lint-python:
     runs-on: ubuntu-latest
     steps:
+      - name: Check out QEMU
+        uses: actions/checkout@v4
       - name: Install tools
         run: |
           sudo apt-get update &&
           sudo apt-get install -y python3-pip
           # ubuntu "latest" is too old to require --break-system-packages ...
-          pip3 install pylint==3.3.3
-      - name: Check out QEMU
-        uses: actions/checkout@v4
+          pip3 install -r scripts/opentitan/requirements.txt
       - name: Lint Python code
         run: |
+          flake8 --config scripts/opentitan/.flake8 scripts/opentitan/*.py \
+          python/qemu/jtagtools python/qemu/ot
           pylint --rcfile scripts/opentitan/.pylintrc -d 'duplicate-code' -d 'fixme' \
-            scripts/opentitan/*.py python/qemu/jtagtools python/qemu/ot
+          scripts/opentitan/*.py python/qemu/jtagtools python/qemu/ot
 
   lint-clang:
     runs-on: ubuntu-24.04

.gitlab-ci.d/opentitan/pylint-ot.yml → .gitlab-ci.d/opentitan/python-ot.yml

@@ -1,4 +1,4 @@
-pylint-ot:
+python-ot:
   tags:
     - qemu_ot
   stage: build
@@ -9,4 +9,6 @@ pylint-ot:
     - . .venv/bin/activate
     - pip3 install -r scripts/opentitan/requirements.txt
     - pylint --rcfile scripts/opentitan/.pylintrc -d 'duplicate-code' -d 'fixme'
-        scripts/opentitan/*.py python/qemu/jtagtools python/qemu/ot
+      scripts/opentitan/*.py python/qemu/jtagtools python/qemu/ot
+    - flake8 --config scripts/opentitan/.flake8
+      scripts/opentitan/*.py python/qemu/jtagtools python/qemu/ot

.gitlab-ci.d/opentitan/qemu-ot.yml

@@ -4,6 +4,6 @@ variables:
 
 include:
   - local: '/.gitlab-ci.d/opentitan/build.yml'
-  - local: '/.gitlab-ci.d/opentitan/pylint-ot.yml'
+  - local: '/.gitlab-ci.d/opentitan/python-ot.yml'
   - local: '/.gitlab-ci.d/opentitan/ot-smoke.yml'
   - local: '/.gitlab-ci.d/opentitan/ot-bmtests.yml'

python/qemu/jtagtools/jtag/__init__.py

@@ -1,11 +1,12 @@
 # Copyright (c) 2024 Rivos Inc. Emmanuel Blot <eblot@rivosinc.com>
 # Copyright (c) 2010-2024, Emmanuel Blot <emmanuel.blot@free.fr>
+# Copyright (c) 2025 lowRISC contributors.
 # All rights reserved.
 #
 # SPDX-License-Identifier: Apache2
 
 """JTAG Tools."""
 
-from .controller import JtagController
-from .engine import JtagEngine
-from .error import JtagError
+from .controller import JtagController  # noqa: F401
+from .engine import JtagEngine  # noqa: F401
+from .error import JtagError  # noqa: F401

python/qemu/jtagtools/jtag/error.py

@@ -1,11 +1,13 @@
 # Copyright (c) 2024 Rivos Inc. Emmanuel Blot <eblot@rivosinc.com>
 # Copyright (c) 2010-2024, Emmanuel Blot <emmanuel.blot@free.fr>
+# Copyright (c) 2025 lowRISC contributors.
 # All rights reserved.
 #
 # SPDX-License-Identifier: Apache2
 
 """JTAG Errors"""
 
+
 class JtagError(Exception):
     """Generic JTAG error."""
 

python/qemu/jtagtools/rbb/__init__.py

@@ -1,8 +1,9 @@
 # Copyright (c) 2024 Rivos Inc. Emmanuel Blot <eblot@rivosinc.com>
+# Copyright (c) 2025 lowRISC contributors.
 # All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
 
 """JTAG Remote BitBang Controller"""
 
-from .bitbang import JtagBitbangController
+from .bitbang import JtagBitbangController  # noqa: F401

python/qemu/ot/devproxy.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2023-2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """Device proxy for OpenTitan devices and peripherals
@@ -1663,7 +1664,7 @@ def _receive(self):
                     continue
                 packet = bytes(buffer[:length])
                 self._log.debug('RX payload:%s%s', self.to_str(packet)[:80],
-                    '...' if len(packet) > 80 else '')
+                                '...' if len(packet) > 80 else '')
                 buffer = buffer[length:]
                 if resp:
                     if self._tx_uid != uid:

python/qemu/ot/dtm/__init__.py

@@ -1,9 +1,10 @@
 # Copyright (c) 2024 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """Debug Module tools.
 
    :author: Emmanuel Blot <eblot@rivosinc.com>
 """
 
-from .dtm import DebugTransportModule
+from .dtm import DebugTransportModule  # noqa: F401

python/qemu/ot/dtm/dtm.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2024 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """Debug Module tools.
@@ -214,7 +215,7 @@ def _build_dmi(self, address: int) -> int:
             self._log.debug('DMI width: %d bits', self._abits)
         if address >= (1 << self._abits):
             raise ValueError(f'Address 0x{address:x} too large, '
-                             f'max 0x{(1 << self._abits) -1:x}')
+                             f'max 0x{(1 << self._abits) - 1:x}')
         return address << (32 + 2)
 
     def _check_error(self) -> None:

python/qemu/ot/km/__init__.py

@@ -1,6 +1,7 @@
 # Copyright (c) 2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """KeyManager tools."""
 
-from .dpe import KeyManagerDpe
+from .dpe import KeyManagerDpe  # noqa: F401

python/qemu/ot/km/dpe.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 
 # Copyright (c) 2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """QEMU OT tool to generate Key Manager DPE keys.
@@ -100,7 +101,7 @@ def from_args(cls, args: Namespace) -> 'KeyManagerDpe':
         if salt_len > cls.SALT_WIDTH:
             raise ArgError('Invalid salt length')
 
-        if not 0<= args.key_version < 1<<32:
+        if not 0 <= args.key_version < 1 << 32:
             raise ArgError('Invalid key version value')
 
         kmd = cls.create(args.otp_map, args.ecc, args.vmem, args.raw,

python/qemu/ot/km/engine.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """QEMU OT tool to verify Key Manager DPE test execution
@@ -165,7 +166,6 @@ def _parse_bytes(cls, value: str) -> bytes:
             return ivalue.to_bytes((ivalue.bit_length() + 7) // 8, 'big')
         raise ValueError(f'invalid bytes: {value}')
 
-
     def _build_steps_from_seq(self, seq: ConfigParser) -> \
             dict[str, KeyManagerDpeStep]:
         module = sys.modules[__name__]
@@ -279,7 +279,7 @@ def _build_steps_from_log(self, itlog: Iterator[str]) -> \
 
     def _enumerate_steps_from_log(self, itlog: Iterator[str]) -> \
             Iterator[tuple[str, dict[str, Union[str, int, bytes, bool]],
-                Optional[bytes]]]:
+                           Optional[bytes]]]:
         step = None
         values: dict[str, Union[str, int, bytes, bool]] = {}
         result: Optional[bytes] = None

python/qemu/ot/lc_ctrl/__init__.py

@@ -1,7 +1,9 @@
 # Copyright (c) 2024 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """LifeCycle tools."""
 
+
 class LifeCycleError(RuntimeError):
     """Life Cycle Error"""

python/qemu/ot/lc_ctrl/const.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """Lifecycle helpers.
@@ -21,7 +22,7 @@ def __init__(self):
         self._log = getLogger('lc.const')
         self._states: dict[str, tuple[str, str]] = {}
         self._tokens: dict[str, str] = {}
-        self._diversifiers: dict [str, str] = {}
+        self._diversifiers: dict[str, str] = {}
 
     def load_sv(self, svp: TextIO) -> None:
         """Decode LC information from a System Verilog file.

python/qemu/ot/lc_ctrl/lcdmi.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2024 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """LifeCycle DMI.
@@ -188,7 +189,8 @@ def transition_token(self) -> bytes:
         return token
 
     @transition_token.setter
-    def transition_token(self, token: Union[bytes, bytearray, str, None]) -> None:
+    def transition_token(self,
+                         token: Union[bytes, bytearray, str, None]) -> None:
         """Define the transition token as a 16-byte token.
 
            :param token: if None, use an empty zeroed token,

python/qemu/ot/otp/const.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2023-2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """Lifecycle helpers.
@@ -141,17 +142,17 @@ def load_secrets(self, secrets: dict[str, Any]) -> bool:
         self._consts['key'] = [
             hexlify(kv.to_bytes(sizes['key'], 'big')).decode()
             for kd in scrambling['keys']
-            for kn, kv in kd.items() if kn =='value'
+            for kn, kv in kd.items() if kn == 'value'
         ]
         self._consts['digest_const'] = [
             hexlify(kv.to_bytes(sizes['cnst'], 'big')).decode()
             for kd in scrambling['digests']
-            for kn, kv in kd.items() if kn =='cnst_value'
+            for kn, kv in kd.items() if kn == 'cnst_value'
         ]
         self._consts['digest_iv'] = [
             hexlify(kv.to_bytes(sizes['iv'], 'big')).decode()
             for kd in scrambling['digests']
-            for kn, kv in kd.items() if kn =='iv_value'
+            for kn, kv in kd.items() if kn == 'iv_value'
         ]
 
         offset = 0

python/qemu/ot/otp/descriptor.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2023-2024 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """OTP descriptors.
@@ -228,7 +229,7 @@ def save(self, kind: str, topname: Optional[str], hjname: str,
                 slots.append(OtpSlotDescriptor(f'{part.name}_DIGEST', offset,
                                                OtpPartition.DIGEST_SIZE, True))
             if zeroizable:
-                offset = part.offset + part.size -  OtpPartition.DIGEST_SIZE
+                offset = part.offset + part.size - OtpPartition.DIGEST_SIZE
                 slots.append(OtpSlotDescriptor(f'{part.name}_ZER', offset,
                                                OtpPartition.ZER_SIZE, True))
 
@@ -264,7 +265,7 @@ def _save_qemu(self, topname: Optional[str], hjname: str, scriptname: str,
         part_names.extend((
             'OTP_PART_COUNT',
             'OTP_ENTRY_DAI = OTP_PART_COUNT, '
-                '/* Fake partitions for error (...) */',
+            '/* Fake partitions for error (...) */',
             'OTP_ENTRY_KDI, /* Key derivation issue, not really OTP */',
             'OTP_ENTRY_COUNT'))
         print('typedef enum {', file=cfp)

python/qemu/ot/otp/image.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2023-2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """OTP QEMU image.
@@ -386,7 +387,7 @@ def decode(self, decode: bool = True, wide: int = 0,
             for partname in partnames:
                 if not re.match(part_re, partname, re.IGNORECASE):
                     continue
-                if not partname in part_filters:
+                if partname not in part_filters:
                     part_filters[partname] = set()
                 if field == '*':
                     # any field would match, discard any existing one

python/qemu/ot/otp/lifecycle.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2023-2024 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """Lifecycle helpers.
@@ -82,8 +83,8 @@ def load(self, svp: TextIO):
         self._sequences = sequences
         svp.seek(0)
         for tmo in re.finditer(r"\s+parameter\s+lc_token_t\s+(\w+)\s+="
-                            r"\s+\{\s+128'h([0-9A-F]+)\s+\};",
-                            svp.getvalue()):
+                               r"\s+\{\s+128'h([0-9A-F]+)\s+\};",
+                               svp.getvalue()):
             token, value = tmo.group(1), tmo.group(2)
             if token in self._tokens:
                 raise ValueError(f'Multiple definitions of token {token}')

python/qemu/ot/pyot/qemu/wrapper.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2023-2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """QEMU executer wrapper for OpentTitan unit test sequencer.
@@ -10,6 +11,7 @@
 
 from ..wrapper import Wrapper
 
+
 class QEMUWrapper(Wrapper):
     """Test execution wrapper using a QEMU virtual machine
     """

python/qemu/ot/util/arg.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2024-2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """ArgumentParser extension.
@@ -8,7 +9,7 @@
 
 # pylint: disable=unused-import
 # ruff: noqa: F401
-from argparse import ArgumentParser as _ArgumentParser, FileType
+from argparse import ArgumentParser as _ArgumentParser
 from sys import stderr
 
 

python/qemu/ot/util/file.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2023-2025 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """File utilities.
@@ -106,7 +107,8 @@ def make_vmem_from_elf(elf_file: Union[str, BinaryIO],
     is_path = isinstance(vmem_file, str)
     with open(vmem_file, 'wt') if is_path else vmem_file as vfp:
         print(f'// name:       {elfname}', file=vfp)
-        print(f'// built:      {strftime("%Y/%m/%d %H:%M:%S", elftime)}', file=vfp)
+        print(f'// built:      {strftime("%Y/%m/%d %H:%M:%S", elftime)}',
+              file=vfp)
         print(f'// size:       {elfstat.st_size}', file=vfp)
         print(f'// rawsize:    {elf.size}', file=vfp)
         print(f'// entrypoint: 0x{elf.entry_point:08x}', file=vfp)

python/qemu/ot/util/log.py

@@ -1,4 +1,5 @@
 # Copyright (c) 2023-2024 Rivos, Inc.
+# Copyright (c) 2025 lowRISC contributors.
 # SPDX-License-Identifier: Apache2
 
 """Logging helpers.
@@ -218,7 +219,7 @@ def handle(self):
             if len(buffer) < self.HEADER_SIZE:
                 continue
             header, buffer = (buffer[:self.HEADER_SIZE],
-                buffer[self.HEADER_SIZE:])
+                              buffer[self.HEADER_SIZE:])
             record_len, = sunpack(self.HEADER_FMT, header)
             while len(buffer) < record_len:
                 data = self.rfile.read(4096)

python/qemu/ot/util/prince.py

@@ -8,6 +8,7 @@
 
 # pylint: disable=missing-docstring
 
+
 class PrinceCipher:
 
     SBOX4 = [
@@ -120,8 +121,8 @@ def inv_round(cls, rc: int, key: int, data: int) -> int:
 
     # Run the PRINCE cipher.
     # This uses the new keyschedule proposed by Dinur in "Cryptanalytic
-    # Time-Memory-Data Tradeoffs for FX-Constructions with Applications to PRINCE
-    # and PRIDE".
+    # Time-Memory-Data Tradeoffs for FX-Constructions with Applications to
+    # PRINCE and PRIDE".
     @classmethod
     def run(cls, data: int, khi: int, klo: int, num_rounds_half: int) -> int:
         khi_rot1 = ((khi & 1) << 63) | (khi >> 1)