Source code for cocotb.scoreboard

#!/usr/bin/env python

# Copyright (c) 2013 Potential Ventures Ltd
# Copyright (c) 2013 SolarFlare Communications Inc
# All rights reserved.
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#     * Redistributions of source code must retain the above copyright
#       notice, this list of conditions and the following disclaimer.
#     * Redistributions in binary form must reproduce the above copyright
#       notice, this list of conditions and the following disclaimer in the
#       documentation and/or other materials provided with the distribution.
#     * Neither the name of Potential Ventures Ltd,
#       SolarFlare Communications Inc nor the
#       names of its contributors may be used to endorse or promote products
#       derived from this software without specific prior written permission.
# 
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL POTENTIAL VENTURES LTD BE LIABLE FOR ANY
# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

"""Common scoreboarding capability."""

import logging

from cocotb.utils import hexdump, hexdiffs
from cocotb.log import SimLog
from cocotb.monitors import Monitor
from cocotb.result import TestFailure, TestSuccess


[docs]class Scoreboard(object): """Generic scoreboarding class. We can add interfaces by providing a monitor and an expected output queue. The expected output can either be a function which provides a transaction or a simple list containing the expected output. TODO: Statistics for end-of-test summary etc. Args: dut (SimHandle): Handle to the DUT. reorder_depth (int, optional): Consider up to `reorder_depth` elements of the expected result list as passing matches. Default is 0, meaning only the first element in the expected result list is considered for a passing match. fail_immediately (bool, optional): Raise :any:`TestFailure` immediately when something is wrong instead of just recording an error. Default is ``True``. """ def __init__(self, dut, reorder_depth=0, fail_immediately=True): # FIXME: reorder_depth needed here? self.dut = dut self.log = SimLog("cocotb.scoreboard.%s" % self.dut._name) self.errors = 0 self.expected = {} self._imm = fail_immediately @property def result(self): """Determine the test result, do we have any pending data remaining? Returns: :any:`TestFailure`: If not all expected output was received or error were recorded during the test. """ fail = False for monitor, expected_output in self.expected.items(): if callable(expected_output): self.log.debug("Can't check all data returned for %s since " "expected output is callable function rather " "than a list" % str(monitor)) continue if len(expected_output): self.log.warn("Still expecting %d transactions on %s" % (len(expected_output), str(monitor))) for index, transaction in enumerate(expected_output): self.log.info("Expecting %d:\n%s" % (index, hexdump(str(transaction)))) if index > 5: self.log.info("... and %d more to come" % (len(expected_output) - index - 1)) break fail = True if fail: return TestFailure("Not all expected output was received") if self.errors: return TestFailure("Errors were recorded during the test") return TestSuccess()
[docs] def compare(self, got, exp, log, strict_type=True): """Common function for comparing two transactions. Can be re-implemented by a sub-class. Args: got: The received transaction. exp: The expected transaction. log: The logger for reporting messages. strict_type (bool, optional): Require transaction type to match exactly if ``True``, otherwise compare its string representation. Raises: :any:`TestFailure`: If received transaction differed from expected transaction when :attr:`fail_immediately` is ``True``. If *strict_type* is ``True``, also the transaction type must match. """ # Compare the types if strict_type and type(got) != type(exp): self.errors += 1 log.error("Received transaction type is different than expected") log.info("Received: %s but expected %s" % (str(type(got)), str(type(exp)))) if self._imm: raise TestFailure("Received transaction of wrong type. " "Set strict_type=False to avoid this.") return # Or convert to a string before comparison elif not strict_type: got, exp = str(got), str(exp) # Compare directly if got != exp: self.errors += 1 # Try our best to print out something useful strgot, strexp = str(got), str(exp) log.error("Received transaction differed from expected output") if not strict_type: log.info("Expected:\n" + hexdump(strexp)) else: log.info("Expected:\n" + repr(exp)) if not isinstance(exp, str): try: for word in exp: log.info(str(word)) except Exception: pass if not strict_type: log.info("Received:\n" + hexdump(strgot)) else: log.info("Received:\n" + repr(got)) if not isinstance(got, str): try: for word in got: log.info(str(word)) except Exception: pass log.warning("Difference:\n%s" % hexdiffs(strexp, strgot)) if self._imm: raise TestFailure("Received transaction differed from expected" "transaction") else: # Don't want to fail the test # if we're passed something without __len__ try: log.debug("Received expected transaction %d bytes" % (len(got))) log.debug(repr(got)) except Exception: pass
[docs] def add_interface(self, monitor, expected_output, compare_fn=None, reorder_depth=0, strict_type=True): """Add an interface to be scoreboarded. Provides a function which the monitor will callback with received transactions. Simply check against the expected output. Args: monitor: The monitor object. expected_output: Queue of expected outputs. compare_fn (callable, optional): Function doing the actual comparison. reorder_depth (int, optional): Consider up to *reorder_depth* elements of the expected result list as passing matches. Default is 0, meaning only the first element in the expected result list is considered for a passing match. strict_type (bool, optional): Require transaction type to match exactly if ``True``, otherwise compare its string representation. Raises: :any:`TypeError`: If no monitor is on the interface or *compare_fn* is not a callable function. """ # save a handle to the expected output so we can check if all expected # data has been received at the end of a test. self.expected[monitor] = expected_output # Enforce some type checking as we only work with a real monitor if not isinstance(monitor, Monitor): raise TypeError("Expected monitor on the interface but got %s" % (monitor.__class__.__name__)) if compare_fn is not None: if callable(compare_fn): monitor.add_callback(compare_fn) return raise TypeError("Expected a callable compare function but got %s" % str(type(compare_fn))) self.log.info("Created with reorder_depth %d" % reorder_depth) def check_received_transaction(transaction): """Called back by the monitor when a new transaction has been received.""" if monitor.name: log_name = self.log.name + '.' + monitor.name else: log_name = self.log.name + '.' + monitor.__class__.__name__ log = logging.getLogger(log_name) if callable(expected_output): exp = expected_output(transaction) elif len(expected_output): # we expect something for i in range(min((reorder_depth + 1), len(expected_output))): if expected_output[i] == transaction: break # break out of enclosing for loop else: # run when for loop is exhausted (but no break occurs) i = 0 exp = expected_output.pop(i) else: self.errors += 1 log.error("Received a transaction but wasn't expecting " "anything") log.info("Got: %s" % (hexdump(str(transaction)))) if self._imm: raise TestFailure("Received a transaction but wasn't " "expecting anything") return self.compare(transaction, exp, log, strict_type=strict_type) monitor.add_callback(check_received_transaction)