Update local bitcell array for dual port

This commit is contained in:
mrg 2020-08-19 11:35:55 -07:00
parent e215c0e016
commit 593a98e29a
2 changed files with 95 additions and 40 deletions

View File

@ -29,6 +29,9 @@ class local_bitcell_array(bitcell_base_array.bitcell_base_array):
self.add_rbl = rbl
else:
self.add_rbl = add_rbl
debug.check(len(self.all_ports) < 3, "Local bitcell array only supports dual port or less.")
self.create_netlist()
if not OPTS.netlist_only:
self.create_layout()
@ -68,66 +71,96 @@ class local_bitcell_array(bitcell_base_array.bitcell_base_array):
self.add_mod(self.bitcell_array)
self.wl_array = factory.create(module_type="wordline_buffer_array",
rows=self.rows + len(self.all_ports),
rows=self.rows + 1,
cols=self.cols)
self.add_mod(self.wl_array)
def add_pins(self):
self.bitline_names = self.bitcell_array.get_all_bitline_names()
self.driver_wordline_inputs = []
self.driver_wordline_outputs = []
self.array_wordline_inputs = []
self.driver_wordline_inputs = [x for x in self.bitcell_array.get_all_wordline_names() if not x.startswith("dummy")]
self.driver_wordline_outputs = [x + "i" for x in self.driver_wordline_inputs]
self.array_wordline_inputs = [x + "i" if not x.startswith("dummy") else "gnd" for x in self.bitcell_array.get_all_wordline_names()]
# Port 0
wordline_inputs = [x for x in self.bitcell_array.get_wordline_names(0) if not x.startswith("dummy")]
if len(self.all_ports) > 1:
# Drop off the RBL for port 1
self.driver_wordline_inputs.append(wordline_inputs[:-1])
else:
self.driver_wordline_inputs.append(wordline_inputs)
self.driver_wordline_outputs.append([x + "i" for x in self.driver_wordline_inputs[-1]])
self.array_wordline_inputs.append([x + "i" if not x.startswith("dummy") else "gnd" for x in self.bitcell_array.get_wordline_names(0)])
# Port 1
if len(self.all_ports) > 1:
self.driver_wordline_inputs.append([x for x in self.bitcell_array.get_wordline_names(1) if not x.startswith("dummy")][1:])
self.driver_wordline_outputs.append([x + "i" for x in self.driver_wordline_inputs[-1]])
self.array_wordline_inputs.append([x + "i" if not x.startswith("dummy") else "gnd" for x in self.bitcell_array.get_wordline_names(1)])
self.all_driver_wordline_inputs = [x for x in self.bitcell_array.get_wordline_names() if not x.startswith("dummy")]
self.replica_names = self.bitcell_array.get_rbl_wordline_names()
self.gnd_wl_names = []
# Connect unused RBL WL to gnd
array_rbl_names = set([x for x in self.bitcell_array.get_all_wordline_names() if x.startswith("rbl")])
dummy_rbl_names = set([x for x in self.bitcell_array.get_all_wordline_names() if x.startswith("dummy")])
rbl_wl_names = set([self.bitcell_array.get_rbl_wordline_names(x) for x in self.all_ports])
self.gnd_wl_names = list((array_rbl_names - rbl_wl_names) | dummy_rbl_names)
self.all_array_wordline_inputs = [x + "i" if x not in self.gnd_wl_names else "gnd" for x in self.bitcell_array.get_wordline_names()]
self.bitline_names = self.bitcell_array.get_inouts()
# Arrays are always:
# word lines (bottom to top)
# bit lines (left to right)
# vdd
# gnd
self.add_pin_list(self.driver_wordline_inputs, "INPUT")
for port in self.all_ports:
self.add_pin_list(self.all_driver_wordline_inputs, "INPUT")
self.add_pin_list(self.bitline_names, "INOUT")
self.add_pin("vdd", "POWER")
self.add_pin("gnd", "GROUND")
def create_instances(self):
""" Create the module instances used in this design """
self.wl_inst = self.add_inst(name="wl_driver",
mod=self.wl_array)
self.connect_inst(self.driver_wordline_inputs + self.driver_wordline_outputs + ["vdd", "gnd"])
self.wl_insts = []
for port in self.all_ports:
self.wl_insts.append(self.add_inst(name="wl_driver",
mod=self.wl_array))
self.connect_inst(self.driver_wordline_inputs[port] + self.driver_wordline_outputs[port] + ["vdd", "gnd"])
self.bitcell_array_inst = self.add_inst(name="array",
mod=self.bitcell_array,
offset=self.wl_inst.lr())
self.connect_inst(self.array_wordline_inputs + self.bitline_names + ["vdd", "gnd"])
mod=self.bitcell_array)
self.connect_inst(self.all_array_wordline_inputs + self.bitline_names + ["vdd", "gnd"])
def place(self):
""" Place the bitcelll array to the right of the wl driver. """
self.wl_inst.place(vector(0, self.cell.height))
# FIXME: Replace this with a tech specific paramter
driver_to_array_spacing = 3 * self.m3_pitch
self.bitcell_array_inst.place(vector(self.wl_inst.rx() + driver_to_array_spacing,
self.wl_insts[0].place(vector(0, self.cell.height))
self.bitcell_array_inst.place(vector(self.wl_insts[0].rx() + driver_to_array_spacing,
0))
if len(self.all_ports) > 1:
self.wl_insts[1].place(vector(self.bitcell_array_inst.rx() + self.wl_array.width + driver_to_array_spacing,
2 * self.cell.height),
mirror="MY")
self.height = self.bitcell_array.height
self.width = self.bitcell_array_inst.rx()
def route_unused_wordlines(self):
""" Connect the unused RBL and dummy wordlines to gnd """
gnd_wl_names = []
# Connect unused RBL WL to gnd
array_rbl_names = set([x for x in self.bitcell_array.get_all_wordline_names() if x.startswith("rbl")])
dummy_rbl_names = set([x for x in self.bitcell_array.get_all_wordline_names() if x.startswith("dummy")])
rbl_wl_names = set([self.bitcell_array.get_rbl_wordline_names(x) for x in self.all_ports])
gnd_wl_names = list((array_rbl_names - rbl_wl_names) | dummy_rbl_names)
for wl_name in gnd_wl_names:
for wl_name in self.gnd_wl_names:
pin = self.bitcell_array_inst.get_pin(wl_name)
pin_layer = pin.layer
layer_pitch = 1.5 * getattr(self, "{}_pitch".format(pin_layer))
@ -149,10 +182,11 @@ class local_bitcell_array(bitcell_base_array.bitcell_base_array):
for (x, y) in zip(self.bitline_names, self.bitcell_array.get_inouts()):
self.copy_layout_pin(self.bitcell_array_inst, y, x)
for (x, y) in zip(self.driver_wordline_inputs, self.wl_array.get_inputs()):
self.copy_layout_pin(self.wl_inst, y, x)
for port in self.all_ports:
for (x, y) in zip(self.driver_wordline_inputs[port], self.wl_array.get_inputs()):
self.copy_layout_pin(self.wl_insts[port], y, x)
supply_insts = [self.wl_inst, self.bitcell_array_inst]
supply_insts = [*self.wl_insts, self.bitcell_array_inst]
for pin_name in ["vdd", "gnd"]:
for inst in supply_insts:
pin_list = inst.get_pins(pin_name)
@ -162,12 +196,28 @@ class local_bitcell_array(bitcell_base_array.bitcell_base_array):
start_layer=pin.layer)
def route(self):
array_names = [x for x in self.bitcell_array.get_all_wordline_names() if not x.startswith("dummy")]
for (driver_name, array_name) in zip(self.wl_array.get_outputs(), array_names):
out_pin = self.wl_inst.get_pin(driver_name)
in_pin = self.bitcell_array_inst.get_pin(array_name)
mid_loc = self.wl_inst.rx() + 1.5 * self.m3_pitch
self.add_path(out_pin.layer, [out_pin.rc(), vector(mid_loc, out_pin.cy()), in_pin.lc()])
for port in self.all_ports:
if port == 0:
array_names = [x for x in self.bitcell_array.get_wordline_names(port) if not x.startswith("dummy")]
if len(self.all_ports) > 1:
# Drop off the RBL for port 1
array_names = array_names[:-1]
else:
array_names = [x for x in self.bitcell_array.get_wordline_names(port) if not x.startswith("dummy")][1:]
for (driver_name, array_name) in zip(self.wl_array.get_outputs(), array_names):
out_pin = self.wl_insts[port].get_pin(driver_name)
in_pin = self.bitcell_array_inst.get_pin(array_name)
if port == 0:
out_loc = out_pin.rc()
mid_loc = vector(self.wl_insts[port].rx() + 1.5 * self.m3_pitch, out_loc.y)
in_loc = in_pin.lc()
else:
out_loc = out_pin.lc()
mid_loc = vector(self.wl_insts[port].lx() - 1.5 * self.m3_pitch, out_loc.y)
in_loc = in_pin.rc()
self.add_path(out_pin.layer, [out_loc, mid_loc, in_loc])
self.route_unused_wordlines()

View File

@ -218,8 +218,10 @@ class replica_bitcell_array(bitcell_base_array.bitcell_base_array):
self.add_pin_list(self.bitline_names, "INOUT")
def add_wordline_pins(self):
# All wordline names for all ports
# Regular wordline names
self.main_wordline_names = []
# Create the full WL names include dummy, replica, and regular bit cells
self.wordline_names = []
# Wordline names for each port
self.wordline_names_by_port = [[] for x in self.all_ports]
@ -234,9 +236,6 @@ class replica_bitcell_array(bitcell_base_array.bitcell_base_array):
# These are the non-indexed names
dummy_cell_wl_names = ["dummy_" + x for x in self.cell.get_all_wl_names()]
# Create the full WL names include dummy, replica, and regular bit cells
self.wordline_names = []
self.dummy_wordline_names["bot"] = ["{0}_bot".format(x) for x in dummy_cell_wl_names]
self.wordline_names.extend(self.dummy_wordline_names["bot"])
@ -250,6 +249,7 @@ class replica_bitcell_array(bitcell_base_array.bitcell_base_array):
# Regular WLs
self.wordline_names.extend(self.bitcell_array_wordline_names)
self.main_wordline_names = self.bitcell_array_wordline_names
# Right port WLs
for port in range(self.left_rbl, self.left_rbl + self.right_rbl):
@ -490,9 +490,14 @@ class replica_bitcell_array(bitcell_base_array.bitcell_base_array):
bl_names = self.replica_bitline_names[port]
return bl_names[2 * port:2 * port + 2]
def get_wordline_names(self):
def get_wordline_names(self, port=None):
""" Return the wordline names """
return self.wordline_names
if port == None:
return self.wordline_names
else:
wl_name = self.cell.get_all_wl_names()[port]
temp = [x for x in self.wordline_names if wl_name in x]
return temp
def get_bitline_names(self):
""" Return the bitline names """