OpenRAM/compiler/modules/local_bitcell_array.py

113 lines
4.1 KiB
Python

# See LICENSE for licensing information.
#
# Copyright (c) 2016-2019 Regents of the University of California and The Board
# of Regents for the Oklahoma Agricultural and Mechanical College
# (acting for and on behalf of Oklahoma State University)
# All rights reserved.
#
import bitcell_base_array
from globals import OPTS
from sram_factory import factory
from vector import vector
import debug
class local_bitcell_array(bitcell_base_array.bitcell_base_array):
"""
A local bitcell array is a bitcell array with a wordline driver.
This can either be a single aray on its own if there is no hierarchical WL
or it can be combined into a larger array with hierarchical WL.
"""
def __init__(self, rows, cols, ports, left_rbl=0, right_rbl=0, add_replica=True, name=""):
super().__init__(name, rows, cols, 0)
debug.info(2, "create local array of size {} rows x {} cols words".format(rows,
cols + left_rbl + right_rbl))
self.rows = rows
self.cols = cols
self.left_rbl = left_rbl
self.right_rbl = right_rbl
self.all_ports = ports
self.create_netlist()
if not OPTS.netlist_only:
self.create_layout()
# We don't offset this because we need to align
# the replica bitcell in the control logic
# self.offset_all_coordinates()
def create_netlist(self):
""" Create and connect the netlist """
self.add_modules()
self.add_pins()
self.create_instances()
def create_layout(self):
self.place()
self.add_layout_pins()
self.add_boundary()
self.DRC_LVS()
def add_modules(self):
""" Add the modules used in this design """
# This is just used for names
self.cell = factory.create(module_type="bitcell")
self.bitcell_array = factory.create(module_type="replica_bitcell_array",
cols=self.cols,
rows=self.rows,
left_rbl=self.left_rbl,
right_rbl=self.right_rbl,
bitcell_ports=self.all_ports)
self.add_mod(self.bitcell_array)
self.wl_array = factory.create(module_type="wordline_buffer_array",
rows=self.rows + len(self.all_ports),
cols=self.cols)
self.add_mod(self.wl_array)
def add_pins(self):
self.bitline_names = self.bitcell_array.get_all_bitline_names()
self.add_pin_list(self.bitline_names, "INOUT")
self.wordline_names = self.bitcell_array.get_all_wordline_names()
self.add_pin_list(self.wordline_names, "INPUT")
self.add_pin("vdd", "POWER")
self.add_pin("gnd", "GROUND")
def create_instances(self):
""" Create the module instances used in this design """
internal_wl_names = [x + "i" for x in self.wordline_names]
self.wl_inst = self.add_inst(name="wl_driver",
mod=self.wl_array)
self.connect_inst(self.wordline_names + internal_wl_names + ["vdd", "gnd"])
self.array_inst = self.add_inst(name="array",
mod=self.bitcell_array,
offset=self.wl_inst.lr())
self.connect_inst(self.bitline_names + internal_wl_names + ["vdd", "gnd"])
def place(self):
""" Place the bitcelll array to the right of the wl driver. """
self.wl_inst.place(vector(0, 0))
self.array_inst.place(self.wl_inst.lr())
self.height = self.bitcell_array.height
self.width = self.array_inst.rx()
def add_layout_pins(self):
for (x, y) in zip(self.bitline_names, self.bitcell_array.get_inouts()):
self.copy_layout_pin(self.array_inst, y, x)
for (x, y) in zip(self.wordline_names, self.wl_array.get_inputs()):
self.copy_layout_pin(self.wl_inst, y, x)