#//
#//----------------------------------------------------------------------------
#// Copyright 2007-2011 Mentor Graphics Corporation
#// Copyright 2007-2011 Cadence Design Systems, Inc.
#// Copyright 2010-2011 Synopsys, Inc.
#// Copyright 2013 NVIDIA Corporation
#// Copyright 2019 Tuomas Poikela (tpoikela)
#// All Rights Reserved Worldwide
#//
#// 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
#//
#// http://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.
#//----------------------------------------------------------------------------
#
from .uvm_set_get_dap_base import uvm_set_get_dap_base
from ..macros.uvm_object_defines import uvm_object_utils
from ..macros.uvm_message_defines import *
from ..base.sv import sv
from ..base.uvm_globals import uvm_check_output_args
ERR_MSG1 = "Attempt to get value on '%s', but the data access policy forbits calling 'get' prior to calling 'set' or 'try_set'!"
#// Class: uvm_set_before_get_dap
#// Provides a 'Set Before Get' Data Access Policy.
#//
#// The 'Set Before Get' Data Access Policy enforces that the value must
#// be written at ~least~ once before it is read. This DAP can be used to
#// pass shared information to multiple components during standard configuration,
#// even if that information hasn't yet been determined.
#//
#// Such DAP objects can be useful for passing a 'placeholder' reference, before
#// the information is actually available. A good example of this would be
#// the virtual sequencer:
#//
#//| typedef uvm_set_before_get_dap#(uvm_sequencer_base) seqr_dap_t;
#//| virtual_seqeuncer_type virtual_sequencer;
#//| agent_type my_agent;
#//| seqr_dap_t seqr_dap;
#//|
#//| function void my_env::build_phase(uvm_phase phase);
#//| seqr_dap = seqr_dap_t::type_id::create("seqr_dap");
#//| // Pass the DAP, because we don't have a reference to the
#//| // real sequencer yet...
#//| uvm_config_db#(seqr_dap_t)::set(this, "virtual_sequencer", "seqr_dap", seqr_dap);
#//|
#//| // Create the virtual sequencer
#//| virtual_sequencer = virtual_sequencer_type::type_id::create("virtual_sequencer", this);
#//|
#//| // Create the agent
#//| agent = agent_type::type_id::create("agent", this);
#//| endfunction
#//|
#//| function void my_env::connect_phase(uvm_phase phase);
#//| // Now that we know the value is good, we can set it
#//| seqr_dap.set(agent.sequencer);
#//| endfunction
#//
#// In the example above, the environment didn't have a reference to the
#// agent's sequencer yet, because the agent hadn't executed its ~build_phase~.
#// The environment needed to give the virtual sequencer a "Set before get" DAP
#// so that the virtual sequencer (and any sequences one it), could ~eventually~
#// see the agent's sequencer, when the reference was finally available. If
#// the virtual sequencer (or any sequences on it) attempted to 'get' the
#// reference to the agent's sequencer ~prior~ to the environment assigning it,
#// an error would have been reported.
#
#class uvm_set_before_get_dap#(type T=int) extends uvm_set_get_dap_base#(T);
[docs]class uvm_set_before_get_dap(uvm_set_get_dap_base):
#
# // Used for self-references
# typedef uvm_set_before_get_dap#(T) this_type;
#
# // Function: new
# // Constructor
def __init__(self, name="unnamed-uvm_set_before_get_dap#(T)"):
uvm_set_get_dap_base.__init__(self, name)
self.m_set = False
self.m_value = None
# // Group: Set/Get Interface
#
# // Function: set
# // Updates the value stored within the DAP.
# //
[docs] def set(self, value):
self.m_set = True
self.m_value = value
# // Function: try_set
# // Attempts to update the value stored within the DAP.
# //
# // ~try_set~ will always return a 1.
# virtual function bit try_set(T value);
# set(value);
# return 1;
# endfunction : try_set
#
# // Function: get
# // Returns the current value stored within the DAP.
# //
# // If 'get' is called before a call to <set> or <try_set>, then
# // an error will be reported.
[docs] def get(self):
if self.m_set is False:
uvm_error("UVM/SET_BEFORE_GET_DAP/NO_SET", sv.sformatf(ERR_MSG1, self.get_full_name()))
return self.m_value
#
# // Function: try_get
# // Attempts to retrieve the current value stored within the DAP
# //
# // If the value has not been 'set', then try_get will return a 0,
# // otherwise it will return a 1, and set ~value~ to the current
# // value stored within the DAP.
[docs] def try_get(self, value):
uvm_check_output_args([value])
if self.m_set is False:
return 0
else:
value.append(self.m_value)
return 1
#
# // Group: Introspection
# //
# // The ~uvm_set_before_get_dap~ cannot support the standard UVM
# // instrumentation methods (~copy~, ~clone~, ~pack~ and
# // ~unpack~), due to the fact that they would potentially
# // violate the access policy.
# //
# // A call to any of these methods will result in an error.
#
# virtual function void do_copy(uvm_object rhs);
# `uvm_error("UVM/SET_BEFORE_GET_DAP/CPY",
# "'copy()' is not supported for 'uvm_set_before_get_dap#(T)'")
# endfunction : do_copy
#
# virtual function void do_pack(uvm_packer packer);
# `uvm_error("UVM/SET_BEFORE_GET_DAP/PCK",
# "'pack()' is not supported for 'uvm_set_before_get_dap#(T)'")
# endfunction : do_pack
#
# virtual function void do_unpack(uvm_packer packer);
# `uvm_error("UVM/SET_BEFORE_GET_DAP/UPK",
# "'unpack()' is not supported for 'uvm_set_before_get_dap#(T)'")
# endfunction : do_unpack
#
# // Group- Reporting
#
# // Function- convert2string
# virtual function string convert2string();
# if (m_set)
# return $sformatf("(%s) %0p [SET]", `uvm_typename(m_value), m_value);
# else
# return $sformatf("(%s) %0p [UNSET]", `uvm_typename(m_value), m_value);
# endfunction : convert2string
#
# // Function- do_print
# virtual function void do_print(uvm_printer printer);
# super.do_print(printer);
# printer.print_field_int("set_state", m_set, $bits(m_set));
# printer.print_generic("value",
# `uvm_typename(m_value),
# 0,
# $sformatf("%0p", m_value));
#
# endfunction : do_print
#
#endclass // uvm_set_before_get_dap
uvm_object_utils(uvm_set_before_get_dap)