OpenRAM/compiler/modules/rom_base_array.py

322 lines
12 KiB
Python

# See LICENSE for licensing information.
#
# Copyright (c) 2016-2021 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.
#
from .bitcell_base_array import bitcell_base_array
from base import vector
from globals import OPTS
from sram_factory import factory
class rom_base_array(bitcell_base_array):
def __init__(self, rows, cols, strap_spacing, bitmap, name="", column_offset=0):
super().__init__(name=name, rows=rows, cols=cols, column_offset=column_offset)
#TODO: data is input in col-major order for ease of parsing, create a function to convert a row-major input to col-major
self.data = bitmap
self.route_layer = 'm1'
self.strap_spacing = strap_spacing
self.create_all_bitline_names()
self.create_all_wordline_names()
self.create_netlist()
self.create_layout()
def create_netlist(self):
self.add_modules()
self.add_pins()
self.create_instances()
def create_layout(self):
#self.add_layout_pins()
self.place_ptx()
self.place_taps()
self.place_rails()
#self.route_horizo ntal_pins(insts=self.cell_inst.values(), layer=self.route_layer, name="S")
#self.route_bitlines()
#self.route_wordlines()
self.add_boundary()
#def add_pins(self):
def add_boundary(self):
self.width = self.dummy.width * self.column_size
self.height = self.dummy.height * self.row_size
super().add_boundary()
def add_modules(self):
# dummy cell, # "dummy" cells represent 0
self.dummy = factory.create(module_type="rom_dummy_cell", route_layer=self.route_layer)
#base cell with no contacts
self.cell_nc = factory.create(module_name="base_mod_0_contact", module_type="rom_base_cell")
#base cell with drain contact
self.cell_dc = factory.create(module_name="base_mod_d_contact", module_type="rom_base_cell", add_drain_contact=self.route_layer)
#base cell with source contact
self.cell_sc = factory.create(module_name="base_mod_s_contact", module_type="rom_base_cell", add_source_contact=self.route_layer)
#base cell with all contacts
self.cell_ac = factory.create(module_name="base_mod_sd_contact", module_type="rom_base_cell", add_source_contact=self.route_layer, add_drain_contact=self.route_layer)
self.poly_tap = factory.create(module_type="rom_poly_tap", strap_length=self.strap_spacing)
self.gnd_rail = factory.create(module_type="rom_array_gnd_tap", length=self.row_size)
def create_instances(self):
self.tap_inst = {}
self.cell_inst = {}
self.cell_list = []
self.current_row = 0
#list of current bitline interconnect nets, starts as the same as the bitline list and is updated when new insts of cells are added
int_bl_list = self.bitline_names[0]
#When rotated correctly rows are word lines
for row in range(self.row_size):
row_list = []
#when rotated correctly cols are bit lines
for col in range(self.column_size):
name = "bit_r{0}_c{1}".format(row, col)
if self.data[row][col] == 1:
# if dummy/0 cell above and below a 1, add a tx with contacts on both drain and source
# if the first row and a 0 above, add both contacts
# if the last row and 0 below add both contacts
#(row == 0 and self.data[row + 1][col] == 0):
if (row < self.row_size - 1 and row > 0 and self.data[row + 1][col] == 0 and self.data[row - 1][col] == 0) or \
(row == self.row_size - 1 and self.data[row - 1][col] == 0):
self.cell_inst[row, col]=self.add_inst(name=name, mod=self.cell_ac)
# if dummy/0 is below and not above, add a source contact
# if in the first row, add a source contact
elif (row > 0 and self.data[row - 1][col] == 0):
self.cell_inst[row, col]=self.add_inst(name=name, mod=self.cell_sc)
elif (row < self.row_size - 1 and self.data[row + 1][col] == 0) or \
(row == self.row_size - 1):
self.cell_inst[row, col]=self.add_inst(name=name, mod=self.cell_dc)
else:
self.cell_inst[row, col]=self.add_inst(name=name, mod=self.cell_nc)
if row == self.row_size - 1 or self.get_next_cell_in_bl(row, col) == -1:
print(self.cell_inst[row, col])
bl_l = int_bl_list[col]
bl_h = "gnd"
else:
bl_l = int_bl_list[col]
int_bl_list[col] = "bl_int_{0}_{1}".format(row, col)
bl_h = int_bl_list[col]
self.connect_inst([bl_h, bl_l, self.wordline_names[0][row], "gnd"])
else:
self.cell_inst[row, col]=self.add_inst(name=name,
mod=self.dummy)
self.connect_inst([])
# when col = 0 bl_h is connected to vdd, otherwise connect to previous bl connection
# when col = col_size - 1 connected to gnd otherwise create new bl connection
#
row_list.append(self.cell_inst[row, col])
if col % self.strap_spacing == 0:
name = "tap_r{0}_c{1}".format(row, col)
self.tap_inst[row, col]=self.add_inst(name=name, mod=self.poly_tap)
self.connect_inst([])
name = "tap_r{0}_c{1}".format(row, self.column_size)
#print(*row_list)
self.tap_inst[row, self.column_size]=self.add_inst(name=name, mod=self.poly_tap)
self.connect_inst([])
self.cell_list.append(row_list)
def create_all_bitline_names(self):
for col in range(self.column_size):
for port in self.all_ports:
self.bitline_names[port].extend(["bl_{0}_{1}".format(port, col)])
# Make a flat list too
self.all_bitline_names = [x for sl in zip(*self.bitline_names) for x in sl]
def place_taps(self):
self.tap_pos = {}
for row in range(self.row_size):
for s_col in range(0, self.column_size, self.strap_spacing):
col = s_col * self.strap_spacing
tap_x = self.dummy.width * col
tap_y = self.dummy.height * row
self.tap_pos[row, col] = vector(tap_x, tap_y)
self.tap_inst[row, col].place(self.tap_pos[row, col])
tap_x = self.dummy.width * self.column_size + self.poly_tap.width
tap_y = self.dummy.height * row
self.tap_pos[row, self.column_size] = vector(tap_x, tap_y)
self.tap_inst[row, self.column_size].place(self.tap_pos[row, self.column_size])
offset=vector(0, 0),
def place_rails(self):
#self.gnd_rail_inst = self.add_inst(name="gnd", mod=self.gnd_rail)
#self.connect_inst([])
print (self.mcon_width)
rail_start = vector(-self.dummy.width / 2 , self.cell_inst[self.row_size - 1,0].uy() )
rail_end = vector(self.dummy.height * (self.row_size ), self.cell_inst[self.row_size - 1,0].uy())
self.add_layout_pin_rect_ends( name="gnd",
layer="m1",
start=rail_start,
end=rail_end)
def place_ptx(self):
self.cell_pos = {}
# rows are bitlines
for row in range(self.row_size):
# columns are word lines
for col in range(self.column_size):
cell_x = (self.dummy.width) * col
cell_y = row * (self.dummy.height)
self.cell_pos[row, col] = vector(cell_x, cell_y)
self.cell_inst[row, col].place(self.cell_pos[row, col], rotate=90)
#cell_x = self.cell.width * col
#cell_y = self.cell.height * row
#print(self.nmos.height + self.nmos.poly_extend_active)
if(self.data[row][col] == 1):
pass
#self.add_label("S_{}_{}".format(row,col), self.route_layer, self.cell_inst[row, col].center())
#self.add_label("D", self.route_layer, self.cell_inst[row, col].center())
#else:
#poly_offset = (self.nmos.contact_offset + vector(0.5 * self.nmos.active_contact.width + 0.5 * self.nmos.poly_width + self.nmos.active_contact_to_gate, 0)) + (0, cell_y)
#poly_offset = (cell_x, cell_y)
#print(cell_x,cell_y)
#self.add_rect(layer="poly",
# offset=poly_offset,
# width=self.nmos.height + self.nmos.poly_extend_active,
# height=self.nmos.poly_width
# )
def route_bitlines(self):
#get first nmos in col
#connect to main bitline wire
#get next nmos in col
#route source to drain
#loop
for col in range(self.column_size):
for row in range(self.row_size ):
#nmos at this position and another nmos further down
if self.data[row][col] == 1 :
next_row = self.get_next_cell_in_bl(row, col)
if next_row != -1:
drain_pin = self.cell_inst[row, col].get_pin("D")
source_pin = self.cell_inst[next_row, col].get_pin("S")
source_pos = source_pin.bc()
drain_pos = drain_pin.bc()
self.add_path(self.route_layer, [drain_pos, source_pos])
def get_next_cell_in_bl(self, row_start, col):
for row in range(row_start + 1, self.row_size):
if self.data[row][col] == 1:
return row
return -1
def get_current_bl_interconnect(self, col):
"""Get interconnect net for bitline(col) currently being connected """
return "bli_{0}_{1}".format(self.current_row, col)
def create_next_bl_interconnect(self, row, col):
"""create a new net name for a bitline interconnect"""
self.current_row = row
return "bli_{0}_{1}".format(row, col)
def get_bitcell_pins(self, row, col):
"""
return the correct nets to attack nmos/cell drain, gate, source, body pins to
"""
bitcell_pins = []
#drain pin
if self.current_row == 0:
bitcell_pins.append(self.bitline_names[0][col])
else:
bitcell_pins.append(self.get_current_bl_interconnect(col))
#gate pin
bitcell_pins.append(self.get_wordline_names()[row])
#source pin
"""If there is another bitcell to be placed below the current cell, """
if self.get_next_cell_in_bl(row, col) == -1:
bitcell_pins.append("gnd")
else:
"""create another interconnect net"""
bitcell_pins.append(self.create_next_bl_interconnect(row, col))
#body pin
bitcell_pins.append("gnd")
return bitcell_pins