OpenRAM/technology/sky130/custom/sky130_bitcell_array.py

94 lines
4.4 KiB
Python

#!/usr/bin/env python3
# See LICENSE for licensing information.
#
# Copyright (c) 2016-2023 Regents of the University of California
# All rights reserved.
#
from openram import debug
from openram.modules import bitcell_array
from openram.sram_factory import factory
from openram import OPTS
from .sky130_bitcell_base_array import sky130_bitcell_base_array
class sky130_bitcell_array(bitcell_array, sky130_bitcell_base_array):
"""
Creates a rows x cols array of memory cells.
Assumes bit-lines and word lines are connected by abutment.
"""
def __init__(self, rows, cols, column_offset=0, name=""):
# Don't call the regular bitcell_array constructor since we don't want its constructor, just
# some of it's useful member functions
sky130_bitcell_base_array.__init__(self, rows=rows, cols=cols, column_offset=column_offset, name=name)
if self.row_size % 2 == 0:
debug.error("Invalid number of rows {}. number of rows (excluding dummy rows) must be odd to connect to col ends".format(self.row_size), -1)
debug.info(1, "Creating {0} {1} x {2}".format(self.name, self.row_size, self.column_size))
self.add_comment("rows: {0} cols: {1}".format(self.row_size, self.column_size))
# This will create a default set of bitline/wordline names
self.create_all_bitline_names()
self.create_all_wordline_names()
self.create_netlist()
if not OPTS.netlist_only:
self.create_layout()
self.add_supply_pins()
def add_modules(self):
""" Add the modules used in this design """
# Bitcell for port names only
self.cell = factory.create(module_type=OPTS.bitcell, version="opt1")
self.cell2 = factory.create(module_type=OPTS.bitcell, version="opt1a")
self.strap = factory.create(module_type="internal", version="wlstrap")
self.strap2 = factory.create(module_type="internal", version="wlstrap_p")
self.strap3 = factory.create(module_type="internal", version="wlstrapa")
self.strap4 = factory.create(module_type="internal", version="wlstrapa_p")
def create_instances(self):
""" Create the module instances used in this design """
self.cell_inst = {}
self.array_layout = []
alternate_bitcell = (self.row_size) % 2
for row in range(0, self.row_size):
row_layout = []
alternate_strap = (self.row_size+1) % 2
for col in range(0, self.column_size):
if alternate_bitcell == 1:
row_layout.append(self.cell)
self.cell_inst[row, col]=self.add_inst(name="row_{}_col_{}_bitcell".format(row, col),
mod=self.cell)
else:
row_layout.append(self.cell2)
self.cell_inst[row, col]=self.add_inst(name="row_{}_col_{}_bitcell".format(row, col),
mod=self.cell2)
self.connect_inst(self.get_bitcell_pins(row, col))
if col != self.column_size - 1:
if alternate_strap:
if row % 2:
name="row_{}_col_{}_wlstrapa_p".format(row, col)
row_layout.append(self.strap4)
self.add_inst(name=name, mod=self.strap4)
else:
name="row_{}_col_{}_wlstrap_p".format(row, col)
row_layout.append(self.strap2)
self.add_inst(name=name, mod=self.strap2)
alternate_strap = 0
else:
if row % 2:
name="row_{}_col_{}_wlstrapa".format(row, col)
row_layout.append(self.strap3)
self.add_inst(name=name.format(row, col), mod=self.strap3)
else:
name="row_{}_col_{}_wlstrap".format(row, col)
row_layout.append(self.strap)
self.add_inst(name=name.format(row, col), mod=self.strap)
alternate_strap = 1
self.connect_inst(self.get_strap_pins(row, col, name))
if alternate_bitcell == 0:
alternate_bitcell = 1
else:
alternate_bitcell = 0
self.array_layout.append(row_layout)