Source code for spinnman.processes.get_routes_process
# Copyright (c) 2015 The University of Manchester
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import struct
from functools import partial
from typing import List, Optional
from spinn_machine import MulticastRoutingEntry, RoutingEntry
from spinnman.messages.scp.impl.read_memory import ReadMemory, Response
from spinnman.constants import UDP_MESSAGE_MAX_SIZE
from .abstract_multi_connection_process import AbstractMultiConnectionProcess
from .abstract_multi_connection_process_connection_selector import (
ConnectionSelector)
# There are 1024 entries in a routing table
_N_ENTRIES = 1024
# 16 entries fit in a 256-byte read
_ENTRIES_PER_READ = 16
# 64 reads of 16 entries are required for 1024 entries
_N_READS = 64
_ROUTE_ENTRY_PATTERN = struct.Struct("<2xBxIII")
class GetMultiCastRoutesProcess(AbstractMultiConnectionProcess[Response]):
"""
A process for reading the multicast routing table of a SpiNNaker chip.
"""
__slots__ = (
"_app_id",
"_entries")
def __init__(self, connection_selector: ConnectionSelector,
app_id: Optional[int] = None):
"""
:param ConnectionSelector connection_selector:
:param int app_id:
"""
super().__init__(connection_selector)
self._entries: List[Optional[MulticastRoutingEntry]] = \
[None] * _N_ENTRIES
self._app_id = app_id
def _add_routing_entry(
self, route_no: int, offset: int, app_id: int, route: int,
key: int, mask: int):
# pylint: disable=too-many-arguments
if route >= 0xFF000000:
return
if self._app_id is not None and self._app_id != app_id:
return
self._entries[route_no + offset] = MulticastRoutingEntry(
key, mask, RoutingEntry(spinnaker_route=route))
def __handle_response(self, offset: int, response: Response):
for route_no in range(_ENTRIES_PER_READ):
entry = _ROUTE_ENTRY_PATTERN.unpack_from(
response.data,
response.offset + route_no * _ROUTE_ENTRY_PATTERN.size)
self._add_routing_entry(route_no, offset, *entry)
[docs]
def get_routes(self, x: int, y: int,
base_address: int) -> List[MulticastRoutingEntry]:
"""
:param int x:
:param int y:
:param int base_address:
:rtype: list(~spinn_machine.MulticastRoutingEntry)
"""
# Create the read requests
offset = 0
scamp_coords = x, y, 0
with self._collect_responses():
for _ in range(_N_READS):
self._send_request(
ReadMemory(
scamp_coords, base_address + (offset * 16),
UDP_MESSAGE_MAX_SIZE),
partial(self.__handle_response, offset))
offset += _ENTRIES_PER_READ
return [entry for entry in self._entries if entry is not None]