# See LICENSE for licensing information. # # Copyright (c) 2016-2021 Regents of the University of California # All rights reserved. # from bitcell_base_array import bitcell_base_array from sram_factory import factory from globals import OPTS class dummy_array(bitcell_base_array): """ Generate a dummy row/column for the replica array. """ def __init__(self, rows, cols, column_offset=0, mirror=0, location="", name=""): super().__init__(rows=rows, cols=cols, column_offset=column_offset, name=name) self.mirror = mirror self.create_netlist() if not OPTS.netlist_only: self.create_layout() def create_netlist(self): """ Create and connect the netlist """ # This will create a default set of bitline/wordline names self.create_all_bitline_names() self.create_all_wordline_names() self.add_modules() self.add_pins() self.create_instances() def create_layout(self): self.place_array("dummy_r{0}_c{1}", self.mirror) self.add_layout_pins() self.add_boundary() self.DRC_LVS() def add_modules(self): """ Add the modules used in this design """ self.dummy_cell = factory.create(module_type=OPTS.dummy_bitcell) self.cell = factory.create(module_type=OPTS.bitcell) self.add_mod(self.dummy_cell) def create_instances(self): """ Create the module instances used in this design """ self.cell_inst = {} for col in range(self.column_size): for row in range(self.row_size): name = "bit_r{0}_c{1}".format(row, col) self.cell_inst[row, col]=self.add_inst(name=name, mod=self.dummy_cell) self.connect_inst(self.get_bitcell_pins(row, col)) def add_pins(self): # bitline pins are not added because they are floating for bl_name in self.get_bitline_names(): self.add_pin(bl_name, "INOUT") # bitline pins are not added because they are floating for wl_name in self.get_wordline_names(): self.add_pin(wl_name, "INPUT") self.add_pin("vdd", "POWER") self.add_pin("gnd", "GROUND") def add_layout_pins(self): """ Add the layout pins """ # Add the bitline metal, but not as pins since they are going to just be floating # For some reason, LVS has an issue if we don't add this metal bitline_names = self.cell.get_all_bitline_names() for col in range(self.column_size): for port in self.all_ports: bl_pin = self.cell_inst[0, col].get_pin(bitline_names[2 * port]) self.add_layout_pin(text="bl_{0}_{1}".format(port, col), layer=bl_pin.layer, offset=bl_pin.ll().scale(1, 0), width=bl_pin.width(), height=self.height) br_pin = self.cell_inst[0, col].get_pin(bitline_names[2 * port + 1]) self.add_layout_pin(text="br_{0}_{1}".format(port, col), layer=br_pin.layer, offset=br_pin.ll().scale(1, 0), width=br_pin.width(), height=self.height) wl_names = self.cell.get_all_wl_names() for row in range(self.row_size): for port in self.all_ports: wl_pins = self.cell_inst[row, 0].get_pins(wl_names[port]) for wl_pin in wl_pins: self.add_layout_pin(text="wl_{0}_{1}".format(port, row), layer=wl_pin.layer, offset=wl_pin.ll().scale(0, 1), width=self.width, height=wl_pin.height()) # Copy a vdd/gnd layout pin from every cell for row in range(self.row_size): for col in range(self.column_size): inst = self.cell_inst[row, col] for pin_name in ["vdd", "gnd"]: self.copy_layout_pin(inst, pin_name) def input_load(self): # FIXME: This appears to be old code from previous characterization. Needs to be updated. wl_wire = self.gen_wl_wire() return wl_wire.return_input_cap()