mirror of https://github.com/VLSIDA/OpenRAM.git
1162 lines
52 KiB
Python
1162 lines
52 KiB
Python
import sys
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from tech import drc, spice
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import debug
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import design
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from math import log,sqrt,ceil
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import contact
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from bank import bank
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import datetime
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import getpass
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from vector import vector
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from globals import OPTS, print_time
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class sram(design.design):
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"""
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Dynamically generated SRAM by connecting banks to control logic. The
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number of banks should be 1 , 2 or 4
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"""
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def __init__(self, word_size, num_words, num_banks, name):
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c = reload(__import__(OPTS.control_logic))
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self.mod_control_logic = getattr(c, OPTS.control_logic)
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c = reload(__import__(OPTS.dff_array))
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self.mod_dff_array = getattr(c, OPTS.dff_array)
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c = reload(__import__(OPTS.bitcell))
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self.mod_bitcell = getattr(c, OPTS.bitcell)
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self.bitcell = self.mod_bitcell()
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c = reload(__import__(OPTS.ms_flop))
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self.mod_ms_flop = getattr(c, OPTS.ms_flop)
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self.ms_flop = self.mod_ms_flop()
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# reset the static duplicate name checker for unit tests
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# in case we create more than one SRAM
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import design
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design.design.name_map=[]
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self.word_size = word_size
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self.num_words = num_words
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self.num_banks = num_banks
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debug.info(2, "create sram of size {0} with {1} num of words".format(self.word_size,
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self.num_words))
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start_time = datetime.datetime.now()
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design.design.__init__(self, name)
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# For different layer width vias
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self.m2m3_offset_fix = vector(0,0.5*(self.m3_width-self.m2_width))
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# M1/M2 routing pitch is based on contacted pitch of the biggest layer
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self.m1_pitch = max(contact.m1m2.width,contact.m1m2.height) + max(self.m1_space,self.m2_space)
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self.m2_pitch = max(contact.m2m3.width,contact.m2m3.height) + max(self.m2_space,self.m3_space)
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self.m3_pitch = max(contact.m2m3.width,contact.m2m3.height) + max(self.m2_space,self.m3_space)
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self.control_size = 6
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self.bank_to_bus_distance = 5*self.m3_width
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self.compute_sizes()
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self.add_pins()
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self.create_layout()
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# Can remove the following, but it helps for debug!
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self.add_lvs_correspondence_points()
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self.offset_all_coordinates()
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sizes = self.find_highest_coords()
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self.width = sizes[0]
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self.height = sizes[1]
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self.DRC_LVS(final_verification=True)
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if not OPTS.is_unit_test:
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print_time("SRAM creation", datetime.datetime.now(), start_time)
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def compute_sizes(self):
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""" Computes the organization of the memory using bitcell size by trying to make it square."""
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debug.check(self.num_banks in [1,2,4], "Valid number of banks are 1 , 2 and 4.")
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self.num_words_per_bank = self.num_words/self.num_banks
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self.num_bits_per_bank = self.word_size*self.num_words_per_bank
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# Compute the area of the bitcells and estimate a square bank (excluding auxiliary circuitry)
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self.bank_area = self.bitcell.width*self.bitcell.height*self.num_bits_per_bank
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self.bank_side_length = sqrt(self.bank_area)
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# Estimate the words per row given the height of the bitcell and the square side length
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self.tentative_num_cols = int(self.bank_side_length/self.bitcell.width)
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self.words_per_row = self.estimate_words_per_row(self.tentative_num_cols, self.word_size)
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# Estimate the number of rows given the tentative words per row
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self.tentative_num_rows = self.num_bits_per_bank / (self.words_per_row*self.word_size)
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self.words_per_row = self.amend_words_per_row(self.tentative_num_rows, self.words_per_row)
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# Fix the number of columns and rows
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self.num_cols = self.words_per_row*self.word_size
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self.num_rows = self.num_words_per_bank/self.words_per_row
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# Compute the address and bank sizes
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self.row_addr_size = int(log(self.num_rows, 2))
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self.col_addr_size = int(log(self.words_per_row, 2))
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self.bank_addr_size = self.col_addr_size + self.row_addr_size
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self.addr_size = self.bank_addr_size + int(log(self.num_banks, 2))
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debug.info(1,"Words per row: {}".format(self.words_per_row))
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def estimate_words_per_row(self,tentative_num_cols, word_size):
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"""This provides a heuristic rounded estimate for the number of words
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per row."""
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if tentative_num_cols < 1.5*word_size:
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return 1
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elif tentative_num_cols > 3*word_size:
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return 4
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else:
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return 2
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def amend_words_per_row(self,tentative_num_rows, words_per_row):
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"""This picks the number of words per row more accurately by limiting
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it to a minimum and maximum.
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"""
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# Recompute the words per row given a hard max
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if(tentative_num_rows > 512):
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debug.check(tentative_num_rows*words_per_row <= 2048, "Number of words exceeds 2048")
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return words_per_row*tentative_num_rows/512
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# Recompute the words per row given a hard min
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if(tentative_num_rows < 16):
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debug.check(tentative_num_rows*words_per_row >= 16, "Minimum number of rows is 16, but given {0}".format(tentative_num_rows))
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return words_per_row*tentative_num_rows/16
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return words_per_row
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def add_pins(self):
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""" Add pins for entire SRAM. """
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for i in range(self.word_size):
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self.add_pin("DATA[{0}]".format(i),"INOUT")
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for i in range(self.addr_size):
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self.add_pin("ADDR[{0}]".format(i),"INPUT")
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# These are used to create the physical pins too
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self.control_logic_inputs=["CSb", "WEb", "OEb"]
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self.control_logic_outputs=["s_en", "w_en", "tri_en", "tri_en_bar", "clk_bar", "clk_buf"]
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self.add_pin_list(self.control_logic_inputs + ["clk"],"INPUT")
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self.add_pin("vdd","POWER")
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self.add_pin("gnd","GROUND")
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def create_layout(self):
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""" Layout creation """
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self.create_modules()
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if self.num_banks == 1:
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self.add_single_bank_modules()
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self.add_single_bank_pins()
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self.route_single_bank()
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elif self.num_banks == 2:
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self.add_two_bank_modules()
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self.route_two_banks()
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elif self.num_banks == 4:
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self.add_four_bank_modules()
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self.route_four_banks()
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else:
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debug.error("Invalid number of banks.",-1)
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def add_four_bank_modules(self):
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""" Adds the modules and the buses to the top level """
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self.compute_bus_sizes()
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self.add_four_banks()
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self.compute_four_bank_offsets()
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self.add_busses()
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self.add_four_bank_logic()
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self.width = self.bank_inst[1].ur().x
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self.height = max(self.control_logic_inst.uy(),self.msb_decoder_inst.uy())
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def add_two_bank_modules(self):
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""" Adds the modules and the buses to the top level """
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self.compute_bus_sizes()
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self.add_two_banks()
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self.compute_two_bank_offsets()
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self.add_busses()
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self.add_two_bank_logic()
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self.width = self.bank_inst[1].ur().x
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self.height = self.control_logic_inst.uy()
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def route_shared_banks(self):
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""" Route the shared signals for two and four bank configurations. """
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# create the input control pins
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for n in self.control_logic_inputs + ["clk"]:
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self.copy_layout_pin(self.control_logic_inst, n.lower(), n)
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# connect the control logic to the control bus
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for n in self.control_logic_outputs + ["vdd", "gnd"]:
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pins = self.control_logic_inst.get_pins(n)
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for pin in pins:
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if pin.layer=="metal2":
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pin_pos = pin.bc()
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break
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rail_pos = vector(pin_pos.x,self.horz_control_bus_positions[n].y)
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self.add_path("metal2",[pin_pos,rail_pos])
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self.add_via_center(("metal1","via1","metal2"),rail_pos)
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# connect the control logic cross bar
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for n in self.control_logic_outputs:
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cross_pos = vector(self.vert_control_bus_positions[n].x,self.horz_control_bus_positions[n].y)
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self.add_via_center(("metal1","via1","metal2"),cross_pos)
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# connect the bank select signals to the vertical bus
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for i in range(self.num_banks):
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pin = self.bank_inst[i].get_pin("bank_sel")
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pin_pos = pin.rc() if i==0 else pin.lc()
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rail_pos = vector(self.vert_control_bus_positions["bank_sel[{}]".format(i)].x,pin_pos.y)
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self.add_path("metal3",[pin_pos,rail_pos])
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self.add_via_center(("metal2","via2","metal3"),rail_pos)
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def route_four_banks(self):
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""" Route all of the signals for the four bank SRAM. """
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self.route_shared_banks()
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# connect the data output to the data bus
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for n in self.data_bus_names:
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for i in [0,1]:
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pin_pos = self.bank_inst[i].get_pin(n).bc()
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rail_pos = vector(pin_pos.x,self.data_bus_positions[n].y)
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self.add_path("metal2",[pin_pos,rail_pos])
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self.add_via_center(("metal2","via2","metal3"),rail_pos)
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for i in [2,3]:
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pin_pos = self.bank_inst[i].get_pin(n).uc()
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rail_pos = vector(pin_pos.x,self.data_bus_positions[n].y)
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self.add_path("metal2",[pin_pos,rail_pos])
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self.add_via_center(("metal2","via2","metal3"),rail_pos)
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# route msb address bits
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# route 2:4 decoder
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self.route_double_msb_address()
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# connect the banks to the vertical address bus
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# connect the banks to the vertical control bus
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for n in self.addr_bus_names + self.control_bus_names:
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# Skip these from the horizontal bus
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if n in ["vdd", "gnd"]: continue
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# This will be the bank select, so skip it
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if n in self.msb_bank_sel_addr: continue
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for bank_id in [0,2]:
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pin0_pos = self.bank_inst[bank_id].get_pin(n).rc()
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pin1_pos = self.bank_inst[bank_id+1].get_pin(n).lc()
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rail_pos = vector(self.vert_control_bus_positions[n].x,pin0_pos.y)
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self.add_path("metal3",[pin0_pos,pin1_pos])
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self.add_via_center(("metal2","via2","metal3"),rail_pos)
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self.route_bank_supply_rails(left_banks=[0,2], bottom_banks=[2,3])
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def compute_bus_sizes(self):
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""" Compute the independent bus widths shared between two and four bank SRAMs """
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# address size + control signals + one-hot bank select signals
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self.num_vertical_line = self.addr_size + self.control_size + log(self.num_banks,2) + 1
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# data bus size
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self.num_horizontal_line = self.word_size
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self.vertical_bus_width = self.m2_pitch*self.num_vertical_line
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# vertical bus height depends on 2 or 4 banks
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self.data_bus_height = self.m3_pitch*self.num_horizontal_line
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self.data_bus_width = 2*(self.bank.width + self.bank_to_bus_distance) + self.vertical_bus_width
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self.control_bus_height = self.m1_pitch*(self.control_size+2)
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self.control_bus_width = self.bank.width + self.bank_to_bus_distance + self.vertical_bus_width
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self.supply_bus_height = self.m1_pitch*2 # 2 for vdd/gnd placed with control bus
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self.supply_bus_width = self.data_bus_width
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# Sanity check to ensure we can fit the control logic above a single bank (0.9 is a hack really)
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debug.check(self.bank.width + self.vertical_bus_width > 0.9*self.control_logic.width, "Bank is too small compared to control logic.")
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def compute_four_bank_offsets(self):
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""" Compute the overall offsets for a four bank SRAM """
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# The main difference is that the four bank SRAM has the data bus in the middle of the four banks
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# as opposed to the top of the banks.
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# In 4 bank SRAM, the height is determined by the bank decoder and address flop
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self.vertical_bus_height = 2*self.bank.height + 4*self.bank_to_bus_distance + self.data_bus_height \
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+ self.supply_bus_height + self.msb_decoder.height + self.msb_address.width
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# The address bus extends down through the power rails, but control and bank_sel bus don't
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self.addr_bus_height = self.vertical_bus_height
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self.vertical_bus_offset = vector(self.bank.width + self.bank_to_bus_distance, 0)
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self.data_bus_offset = vector(0, self.bank.height + self.bank_to_bus_distance)
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self.supply_bus_offset = vector(0, self.data_bus_offset.y + self.data_bus_height + self.bank.height + 2*self.bank_to_bus_distance)
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self.control_bus_offset = vector(0, self.supply_bus_offset.y + self.supply_bus_height)
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self.bank_sel_bus_offset = self.vertical_bus_offset + vector(self.m2_pitch*self.control_size,0)
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self.addr_bus_offset = self.bank_sel_bus_offset.scale(1,0) + vector(self.m2_pitch*self.num_banks,0)
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# Control is placed at the top above the control bus and everything
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self.control_logic_position = vector(0, self.control_bus_offset.y + self.control_bus_height + self.m1_pitch)
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# Bank select flops get put to the right of control logic above bank1 and the buses
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# Leave a pitch to get the vdd rails up to M2
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self.msb_address_position = vector(self.bank_inst[1].lx() + 3*self.supply_rail_pitch,
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self.supply_bus_offset.y + self.supply_bus_height + 2*self.m1_pitch + self.msb_address.width)
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# Decoder goes above the MSB address flops, and is flipped in Y
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# separate the two by a bank to bus distance for nwell rules, just in case
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self.msb_decoder_position = self.msb_address_position + vector(self.msb_decoder.width, self.bank_to_bus_distance)
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def compute_two_bank_offsets(self):
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""" Compute the overall offsets for a two bank SRAM """
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# In 2 bank SRAM, the height is determined by the control bus which is higher than the msb address
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self.vertical_bus_height = self.bank.height + 2*self.bank_to_bus_distance + self.data_bus_height + self.control_bus_height
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# The address bus extends down through the power rails, but control and bank_sel bus don't
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self.addr_bus_height = self.vertical_bus_height
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self.vertical_bus_offset = vector(self.bank.width + self.bank_to_bus_distance, 0)
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self.data_bus_offset = vector(0, self.bank.height + self.bank_to_bus_distance)
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self.supply_bus_offset = vector(0, self.data_bus_offset.y + self.data_bus_height)
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self.control_bus_offset = vector(0, self.supply_bus_offset.y + self.supply_bus_height)
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self.bank_sel_bus_offset = self.vertical_bus_offset + vector(self.m2_pitch*self.control_size,0)
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self.addr_bus_offset = self.bank_sel_bus_offset.scale(1,0) + vector(self.m2_pitch*self.num_banks,0)
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# Control is placed at the top above the control bus and everything
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self.control_logic_position = vector(0, self.control_bus_offset.y + self.control_bus_height + self.m1_pitch)
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# Bank select flops get put to the right of control logic above bank1 and the buses
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# Leave a pitch to get the vdd rails up to M2
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self.msb_address_position = vector(self.bank_inst[1].lx() + 3*self.supply_rail_pitch,
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self.supply_bus_offset.y+self.supply_bus_height + 2*self.m1_pitch + self.msb_address.width)
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def add_busses(self):
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""" Add the horizontal and vertical busses """
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# Vertical bus
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# The order of the control signals on the control bus:
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self.control_bus_names = ["clk_buf", "tri_en_bar", "tri_en", "clk_bar", "w_en", "s_en"]
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self.vert_control_bus_positions = self.create_bus(layer="metal2",
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pitch=self.m2_pitch,
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offset=self.vertical_bus_offset,
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names=self.control_bus_names,
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length=self.vertical_bus_height,
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vertical=True)
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self.addr_bus_names=["A[{}]".format(i) for i in range(self.addr_size)]
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self.vert_control_bus_positions.update(self.create_bus(layer="metal2",
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pitch=self.m2_pitch,
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offset=self.addr_bus_offset,
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names=self.addr_bus_names,
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length=self.addr_bus_height,
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vertical=True,
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make_pins=True))
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self.bank_sel_bus_names = ["bank_sel[{}]".format(i) for i in range(self.num_banks)]
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self.vert_control_bus_positions.update(self.create_bus(layer="metal2",
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pitch=self.m2_pitch,
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offset=self.bank_sel_bus_offset,
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names=self.bank_sel_bus_names,
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length=self.vertical_bus_height,
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vertical=True))
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# Horizontal data bus
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self.data_bus_names = ["DATA[{}]".format(i) for i in range(self.word_size)]
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self.data_bus_positions = self.create_bus(layer="metal3",
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pitch=self.m3_pitch,
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offset=self.data_bus_offset,
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names=self.data_bus_names,
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length=self.data_bus_width,
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vertical=False,
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make_pins=True)
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# Horizontal control logic bus
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# vdd/gnd in bus go along whole SRAM
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# FIXME: Fatten these wires?
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self.horz_control_bus_positions = self.create_bus(layer="metal1",
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pitch=self.m1_pitch,
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offset=self.supply_bus_offset,
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names=["vdd"],
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length=self.supply_bus_width,
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vertical=False)
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# The gnd rail must not be the entire width since we protrude the right-most vdd rail up for
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# the decoder in 4-bank SRAMs
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self.horz_control_bus_positions.update(self.create_bus(layer="metal1",
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pitch=self.m1_pitch,
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offset=self.supply_bus_offset+vector(0,self.m1_pitch),
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names=["gnd"],
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length=self.supply_bus_width,
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vertical=False))
|
|
self.horz_control_bus_positions.update(self.create_bus(layer="metal1",
|
|
pitch=self.m1_pitch,
|
|
offset=self.control_bus_offset,
|
|
names=self.control_bus_names,
|
|
length=self.control_bus_width,
|
|
vertical=False))
|
|
|
|
def add_two_bank_logic(self):
|
|
""" Add the control and MSB logic """
|
|
|
|
self.add_control_logic(position=self.control_logic_position, rotate=0)
|
|
|
|
self.msb_address_inst = self.add_inst(name="msb_address",
|
|
mod=self.msb_address,
|
|
offset=self.msb_address_position,
|
|
rotate=270)
|
|
self.msb_bank_sel_addr = "ADDR[{}]".format(self.addr_size-1)
|
|
self.connect_inst([self.msb_bank_sel_addr,"bank_sel[1]","bank_sel[0]","clk_buf", "vdd", "gnd"])
|
|
|
|
def add_four_bank_logic(self):
|
|
""" Add the control and MSB decode/bank select logic for four banks """
|
|
|
|
|
|
self.add_control_logic(position=self.control_logic_position, rotate=0)
|
|
|
|
self.msb_address_inst = self.add_inst(name="msb_address",
|
|
mod=self.msb_address,
|
|
offset=self.msb_address_position,
|
|
rotate=270)
|
|
|
|
self.msb_bank_sel_addr = ["ADDR[{}]".format(i) for i in range(self.addr_size-2,self.addr_size,1)]
|
|
temp = list(self.msb_bank_sel_addr)
|
|
temp.extend(["msb{0}[{1}]".format(j,i) for i in range(2) for j in ["","_bar"]])
|
|
temp.extend(["clk_buf", "vdd", "gnd"])
|
|
self.connect_inst(temp)
|
|
|
|
self.msb_decoder_inst = self.add_inst(name="msb_decoder",
|
|
mod=self.msb_decoder,
|
|
offset=self.msb_decoder_position,
|
|
mirror="MY")
|
|
temp = ["msb[{}]".format(i) for i in range(2)]
|
|
temp.extend(["bank_sel[{}]".format(i) for i in range(4)])
|
|
temp.extend(["vdd", "gnd"])
|
|
self.connect_inst(temp)
|
|
|
|
|
|
def route_two_banks(self):
|
|
""" Route all of the signals for the two bank SRAM. """
|
|
|
|
self.route_shared_banks()
|
|
|
|
# connect the horizontal control bus to the vertical bus
|
|
# connect the data output to the data bus
|
|
for n in self.data_bus_names:
|
|
for i in [0,1]:
|
|
pin_pos = self.bank_inst[i].get_pin(n).uc()
|
|
rail_pos = vector(pin_pos.x,self.data_bus_positions[n].y)
|
|
self.add_path("metal2",[pin_pos,rail_pos])
|
|
self.add_via_center(("metal2","via2","metal3"),rail_pos)
|
|
|
|
self.route_single_msb_address()
|
|
|
|
# connect the banks to the vertical address bus
|
|
# connect the banks to the vertical control bus
|
|
for n in self.addr_bus_names + self.control_bus_names:
|
|
# Skip these from the horizontal bus
|
|
if n in ["vdd", "gnd"]: continue
|
|
# This will be the bank select, so skip it
|
|
if n == self.msb_bank_sel_addr: continue
|
|
pin0_pos = self.bank_inst[0].get_pin(n).rc()
|
|
pin1_pos = self.bank_inst[1].get_pin(n).lc()
|
|
rail_pos = vector(self.vert_control_bus_positions[n].x,pin0_pos.y)
|
|
self.add_path("metal3",[pin0_pos,pin1_pos])
|
|
self.add_via_center(("metal2","via2","metal3"),rail_pos)
|
|
|
|
|
|
self.route_bank_supply_rails(left_banks=[0], bottom_banks=[0,1])
|
|
|
|
|
|
def route_double_msb_address(self):
|
|
""" Route two MSB address bits and the bank decoder for 4-bank SRAM """
|
|
|
|
# connect the MSB flops to the address input bus
|
|
for i in [0,1]:
|
|
msb_pins = self.msb_address_inst.get_pins("din[{}]".format(i))
|
|
for msb_pin in msb_pins:
|
|
if msb_pin.layer == "metal3":
|
|
msb_pin_pos = msb_pin.lc()
|
|
break
|
|
rail_pos = vector(self.vert_control_bus_positions[self.msb_bank_sel_addr[i]].x,msb_pin_pos.y)
|
|
self.add_path("metal3",[msb_pin_pos,rail_pos])
|
|
self.add_via_center(("metal2","via2","metal3"),rail_pos)
|
|
|
|
# Connect clk
|
|
clk_pin = self.msb_address_inst.get_pin("clk")
|
|
clk_pos = clk_pin.bc()
|
|
rail_pos = self.horz_control_bus_positions["clk_buf"]
|
|
bend_pos = vector(clk_pos.x,self.horz_control_bus_positions["clk_buf"].y)
|
|
self.add_path("metal1",[clk_pos,bend_pos,rail_pos])
|
|
|
|
# Connect bank decoder outputs to the bank select vertical bus wires
|
|
for i in range(self.num_banks):
|
|
msb_pin = self.msb_decoder_inst.get_pin("out[{}]".format(i))
|
|
msb_pin_pos = msb_pin.lc()
|
|
rail_pos = vector(self.vert_control_bus_positions["bank_sel[{}]".format(i)].x,msb_pin_pos.y)
|
|
self.add_path("metal1",[msb_pin_pos,rail_pos])
|
|
self.add_via_center(("metal1","via1","metal2"),rail_pos)
|
|
|
|
# connect MSB flop outputs to the bank decoder inputs
|
|
msb_pin = self.msb_address_inst.get_pin("dout[0]")
|
|
msb_pin_pos = msb_pin.rc()
|
|
in_pin = self.msb_decoder_inst.get_pin("in[0]")
|
|
in_pos = in_pin.bc() + vector(0,1*self.m2_pitch,) # pin is up from bottom
|
|
out_pos = msb_pin_pos + vector(1*self.m2_pitch,0) # route out to the right
|
|
up_pos = vector(out_pos.x,in_pos.y) # and route up to the decoer
|
|
self.add_wire(("metal1","via1","metal2"),[msb_pin_pos,out_pos,up_pos,in_pos])
|
|
self.add_via_center(("metal1","via1","metal2"),in_pos)
|
|
self.add_via_center(("metal1","via1","metal2"),msb_pin_pos,rotate=90)
|
|
|
|
msb_pin = self.msb_address_inst.get_pin("dout[1]")
|
|
msb_pin_pos = msb_pin.rc()
|
|
in_pin = self.msb_decoder_inst.get_pin("in[1]")
|
|
in_pos = in_pin.bc() + vector(0,self.bitcell.height+self.m2_pitch) # route the next row up
|
|
out_pos = msb_pin_pos + vector(2*self.m2_pitch,0) # route out to the right
|
|
up_pos = vector(out_pos.x,in_pos.y) # and route up to the decoer
|
|
self.add_wire(("metal1","via1","metal2"),[msb_pin_pos,out_pos,up_pos,in_pos])
|
|
self.add_via_center(("metal1","via1","metal2"),in_pos)
|
|
self.add_via_center(("metal1","via1","metal2"),msb_pin_pos,rotate=90)
|
|
|
|
self.route_double_msb_address_supplies()
|
|
|
|
def route_double_msb_address_supplies(self):
|
|
""" Route the vdd/gnd bits of the 2-bit bank decoder. """
|
|
|
|
# Route the right-most vdd/gnd of the right upper bank to the top of the decoder
|
|
vdd_pins = self.bank_inst[1].get_pins("vdd")
|
|
left_bank_vdd_pin = None
|
|
right_bank_vdd_pin = None
|
|
for vdd_pin in vdd_pins:
|
|
if vdd_pin.layer != "metal2":
|
|
continue
|
|
if left_bank_vdd_pin == None or vdd_pin.lx()<left_bank_vdd_pin.lx():
|
|
left_bank_vdd_pin = vdd_pin
|
|
if right_bank_vdd_pin == None or vdd_pin.lx()>right_bank_vdd_pin.lx():
|
|
right_bank_vdd_pin = vdd_pin
|
|
# Route to top
|
|
self.add_rect(layer="metal2",
|
|
offset=vdd_pin.ul(),
|
|
height=self.height-vdd_pin.uy(),
|
|
width=vdd_pin.width())
|
|
|
|
gnd_pins = self.bank_inst[1].get_pins("gnd")
|
|
left_bank_gnd_pin = None
|
|
right_bank_gnd_pin = None
|
|
for gnd_pin in gnd_pins:
|
|
if gnd_pin.layer != "metal2":
|
|
continue
|
|
if left_bank_gnd_pin == None or gnd_pin.lx()<left_bank_gnd_pin.lx():
|
|
left_bank_gnd_pin = gnd_pin
|
|
if right_bank_gnd_pin == None or gnd_pin.lx()>right_bank_gnd_pin.lx():
|
|
right_bank_gnd_pin = gnd_pin
|
|
# Route to top
|
|
self.add_rect(layer="metal2",
|
|
offset=gnd_pin.ul(),
|
|
height=self.height-gnd_pin.uy(),
|
|
width=gnd_pin.width())
|
|
|
|
# Connect bank decoder vdd/gnd supplies using the previous bank pins
|
|
vdd_pins = self.msb_decoder_inst.get_pins("vdd")
|
|
for vdd_pin in vdd_pins:
|
|
if vdd_pin.layer != "metal1":
|
|
continue
|
|
rail1_pos = vector(left_bank_vdd_pin.cx(),vdd_pin.cy())
|
|
rail2_pos = vector(right_bank_vdd_pin.cx(),vdd_pin.cy())
|
|
self.add_path("metal1",[rail1_pos,rail2_pos])
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=rail1_pos,
|
|
rotate=90,
|
|
size=[1,3])
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=rail2_pos,
|
|
rotate=90,
|
|
size=[1,3])
|
|
gnd_pins = self.msb_decoder_inst.get_pins("gnd")
|
|
for gnd_pin in gnd_pins:
|
|
if gnd_pin.layer != "metal1":
|
|
continue
|
|
rail1_pos = vector(left_bank_gnd_pin.cx(),gnd_pin.cy())
|
|
rail2_pos = vector(right_bank_gnd_pin.cx(),gnd_pin.cy())
|
|
self.add_path("metal1",[rail1_pos,rail2_pos])
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=rail1_pos,
|
|
rotate=90,
|
|
size=[1,3])
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=rail2_pos,
|
|
rotate=90,
|
|
size=[1,3])
|
|
|
|
# connect the bank MSB flop supplies
|
|
vdd_pins = self.msb_address_inst.get_pins("vdd")
|
|
# vdd pins go down to the rail
|
|
for vdd_pin in vdd_pins:
|
|
if vdd_pin.layer != "metal1":
|
|
continue
|
|
vdd_pos = vdd_pin.bc()
|
|
down_pos = vdd_pos - vector(0,self.m1_pitch)
|
|
rail_pos = vector(vdd_pos.x,self.horz_control_bus_positions["vdd"].y)
|
|
self.add_path("metal1",[vdd_pos,down_pos])
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=down_pos,
|
|
rotate=90)
|
|
self.add_path("metal2",[down_pos,rail_pos])
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=rail_pos)
|
|
# gnd pins go right to the rail
|
|
gnd_pins = self.msb_address_inst.get_pins("gnd")
|
|
for gnd_pin in gnd_pins:
|
|
if gnd_pin.layer != "metal2":
|
|
continue
|
|
rail1_pos = vector(left_bank_gnd_pin.cx(),gnd_pin.cy())
|
|
self.add_path("metal1",[rail1_pos,gnd_pin.lc()])
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=gnd_pin.lc(),
|
|
rotate=90)
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=rail1_pos,
|
|
rotate=90,
|
|
size=[1,3])
|
|
|
|
def route_single_msb_address(self):
|
|
""" Route one MSB address bit for 2-bank SRAM """
|
|
|
|
# connect the bank MSB flop supplies
|
|
vdd_pins = self.msb_address_inst.get_pins("vdd")
|
|
for vdd_pin in vdd_pins:
|
|
if vdd_pin.layer != "metal1": continue
|
|
vdd_pos = vdd_pin.bc()
|
|
down_pos = vdd_pos - vector(0,self.m1_pitch)
|
|
rail_pos = vector(vdd_pos.x,self.horz_control_bus_positions["vdd"].y)
|
|
self.add_path("metal1",[vdd_pos,down_pos])
|
|
self.add_via_center(("metal1","via1","metal2"),down_pos,rotate=90)
|
|
self.add_path("metal2",[down_pos,rail_pos])
|
|
self.add_via_center(("metal1","via1","metal2"),rail_pos)
|
|
|
|
gnd_pins = self.msb_address_inst.get_pins("gnd")
|
|
# Only add the ground connection to the lowest metal2 rail in the flop array
|
|
# FIXME: SCMOS doesn't have a vertical rail in the cell, or we could use those
|
|
lowest_y = None
|
|
for gnd_pin in gnd_pins:
|
|
if gnd_pin.layer != "metal2": continue
|
|
if lowest_y==None or gnd_pin.by()<lowest_y:
|
|
lowest_y=gnd_pin.by()
|
|
gnd_pos = gnd_pin.ur()
|
|
rail_pos = vector(gnd_pos.x,self.horz_control_bus_positions["gnd"].y)
|
|
self.add_path("metal2",[gnd_pos,rail_pos])
|
|
self.add_via_center(("metal1","via1","metal2"),rail_pos)
|
|
|
|
# connect the MSB flop to the address input bus
|
|
msb_pins = self.msb_address_inst.get_pins("din[0]")
|
|
for msb_pin in msb_pins:
|
|
if msb_pin.layer == "metal3":
|
|
msb_pin_pos = msb_pin.lc()
|
|
break
|
|
rail_pos = vector(self.vert_control_bus_positions[self.msb_bank_sel_addr].x,msb_pin_pos.y)
|
|
self.add_path("metal3",[msb_pin_pos,rail_pos])
|
|
self.add_via_center(("metal2","via2","metal3"),rail_pos)
|
|
|
|
# Connect the output bar to select 0
|
|
msb_out_pin = self.msb_address_inst.get_pin("dout_bar[0]")
|
|
msb_out_pos = msb_out_pin.rc()
|
|
out_extend_right_pos = msb_out_pos + vector(2*self.m2_pitch,0)
|
|
out_extend_up_pos = out_extend_right_pos + vector(0,self.m2_width)
|
|
rail_pos = vector(self.vert_control_bus_positions["bank_sel[0]"].x,out_extend_up_pos.y)
|
|
self.add_path("metal2",[msb_out_pos,out_extend_right_pos,out_extend_up_pos])
|
|
self.add_wire(("metal3","via2","metal2"),[out_extend_right_pos,out_extend_up_pos,rail_pos])
|
|
self.add_via_center(("metal2","via2","metal3"),rail_pos)
|
|
|
|
# Connect the output to select 1
|
|
msb_out_pin = self.msb_address_inst.get_pin("dout[0]")
|
|
msb_out_pos = msb_out_pin.rc()
|
|
out_extend_right_pos = msb_out_pos + vector(2*self.m2_pitch,0)
|
|
out_extend_down_pos = out_extend_right_pos - vector(0,2*self.m1_pitch)
|
|
rail_pos = vector(self.vert_control_bus_positions["bank_sel[1]"].x,out_extend_down_pos.y)
|
|
self.add_path("metal2",[msb_out_pos,out_extend_right_pos,out_extend_down_pos])
|
|
self.add_wire(("metal3","via2","metal2"),[out_extend_right_pos,out_extend_down_pos,rail_pos])
|
|
self.add_via_center(("metal2","via2","metal3"),rail_pos)
|
|
|
|
# Connect clk
|
|
clk_pin = self.msb_address_inst.get_pin("clk")
|
|
clk_pos = clk_pin.bc()
|
|
rail_pos = self.horz_control_bus_positions["clk_buf"]
|
|
bend_pos = vector(clk_pos.x,self.horz_control_bus_positions["clk_buf"].y)
|
|
self.add_path("metal1",[clk_pos,bend_pos,rail_pos])
|
|
|
|
|
|
|
|
def route_bank_supply_rails(self, left_banks, bottom_banks):
|
|
""" Create rails at bottom. Connect veritcal rails to top and bottom. """
|
|
|
|
for i in left_banks:
|
|
vdd_pins = self.bank_inst[i].get_pins("vdd")
|
|
for vdd_pin in vdd_pins:
|
|
if vdd_pin.layer != "metal1":
|
|
continue
|
|
self.add_layout_pin(text="vdd",
|
|
layer=vdd_pin.layer,
|
|
offset=vdd_pin.ll(),
|
|
height=vdd_pin.height(),
|
|
width=self.width)
|
|
|
|
gnd_pins = self.bank_inst[i].get_pins("gnd")
|
|
for gnd_pin in gnd_pins:
|
|
if gnd_pin.layer != "metal1":
|
|
continue
|
|
self.add_layout_pin(text="gnd",
|
|
layer=gnd_pin.layer,
|
|
offset=gnd_pin.ll(),
|
|
height=gnd_pin.height(),
|
|
width=self.width)
|
|
|
|
|
|
|
|
# route bank vertical rails to bottom
|
|
for i in bottom_banks:
|
|
vdd_pins = self.bank_inst[i].get_pins("vdd")
|
|
for vdd_pin in vdd_pins:
|
|
if vdd_pin.layer != "metal2":
|
|
continue
|
|
# Route from bottom to top
|
|
self.add_rect(layer=vdd_pin.layer,
|
|
offset=vdd_pin.ll(),
|
|
height=self.horz_control_bus_positions["vdd"].y,
|
|
width=vdd_pin.width())
|
|
# Add vias at top
|
|
rail_pos = vector(vdd_pin.cx(),self.horz_control_bus_positions["vdd"].y)
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=rail_pos,
|
|
rotate=90,
|
|
size=[1,3])
|
|
|
|
gnd_pins = self.bank_inst[i].get_pins("gnd")
|
|
for gnd_pin in gnd_pins:
|
|
if gnd_pin.layer != "metal2":
|
|
continue
|
|
# Route from bottom to top
|
|
self.add_rect(layer=gnd_pin.layer,
|
|
offset=gnd_pin.ll(),
|
|
height=self.horz_control_bus_positions["gnd"].y,
|
|
width=gnd_pin.width())
|
|
# Add vias at top
|
|
rail_pos = vector(gnd_pin.cx(),self.horz_control_bus_positions["gnd"].y)
|
|
self.add_via_center(layers=("metal1","via1","metal2"),
|
|
offset=rail_pos,
|
|
rotate=90,
|
|
size=[1,3])
|
|
|
|
|
|
|
|
def create_multi_bank_modules(self):
|
|
""" Create the multibank address flops and bank decoder """
|
|
self.msb_address = self.mod_ms_flop_array(name="msb_address",
|
|
columns=self.num_banks/2,
|
|
word_size=self.num_banks/2)
|
|
self.add_mod(self.msb_address)
|
|
|
|
if self.num_banks>2:
|
|
self.msb_decoder = self.bank.decoder.pre2_4
|
|
self.add_mod(self.msb_decoder)
|
|
|
|
def create_modules(self):
|
|
""" Create all the modules that will be used """
|
|
|
|
# Create the control logic module
|
|
self.control_logic = self.mod_control_logic(num_rows=self.num_rows)
|
|
self.add_mod(self.control_logic)
|
|
|
|
# Create the address and control flops
|
|
dff_size = self.addr_size + len(self.control_logic_inputs)
|
|
self.addr_ctrl_dff = self.mod_dff_array(rows=dff_size, columns=1)
|
|
self.add_mod(self.addr_ctrl_dff)
|
|
|
|
# Create the bank module (up to four are instantiated)
|
|
self.bank = bank(word_size=self.word_size,
|
|
num_words=self.num_words_per_bank,
|
|
words_per_row=self.words_per_row,
|
|
num_banks=self.num_banks,
|
|
name="bank")
|
|
self.add_mod(self.bank)
|
|
|
|
# Create bank decoder
|
|
if(self.num_banks > 1):
|
|
self.create_multi_bank_modules()
|
|
|
|
self.bank_count = 0
|
|
|
|
self.supply_rail_width = self.bank.supply_rail_width
|
|
self.supply_rail_pitch = self.bank.supply_rail_pitch
|
|
|
|
|
|
|
|
def add_bank(self, bank_num, position, x_flip, y_flip):
|
|
""" Place a bank at the given position with orientations """
|
|
|
|
# x_flip == 1 --> no flip in x_axis
|
|
# x_flip == -1 --> flip in x_axis
|
|
# y_flip == 1 --> no flip in y_axis
|
|
# y_flip == -1 --> flip in y_axis
|
|
|
|
# x_flip and y_flip are used for position translation
|
|
|
|
if x_flip == -1 and y_flip == -1:
|
|
bank_rotation = 180
|
|
else:
|
|
bank_rotation = 0
|
|
|
|
if x_flip == y_flip:
|
|
bank_mirror = "R0"
|
|
elif x_flip == -1:
|
|
bank_mirror = "MX"
|
|
elif y_flip == -1:
|
|
bank_mirror = "MY"
|
|
else:
|
|
bank_mirror = "R0"
|
|
|
|
bank_inst=self.add_inst(name="bank{0}".format(bank_num),
|
|
mod=self.bank,
|
|
offset=position,
|
|
mirror=bank_mirror,
|
|
rotate=bank_rotation)
|
|
|
|
temp = []
|
|
for i in range(self.word_size):
|
|
temp.append("DATA[{0}]".format(i))
|
|
for i in range(self.bank_addr_size):
|
|
temp.append("ADDR[{0}]".format(i))
|
|
if(self.num_banks > 1):
|
|
temp.append("bank_sel[{0}]".format(bank_num))
|
|
temp.extend(["s_en", "w_en", "tri_en_bar", "tri_en",
|
|
"clk_bar","clk_buf" , "vdd", "gnd"])
|
|
self.connect_inst(temp)
|
|
|
|
return bank_inst
|
|
|
|
# FIXME: This should be in geometry.py or it's own class since it is
|
|
# reusable
|
|
def create_bus(self, layer, pitch, offset, names, length, vertical=False, make_pins=False):
|
|
""" Create a horizontal or vertical bus. It can be either just rectangles, or actual
|
|
layout pins. It returns an map of line center line positions indexed by name. """
|
|
|
|
# half minwidth so we can return the center line offsets
|
|
half_minwidth = 0.5*drc["minwidth_{}".format(layer)]
|
|
|
|
line_positions = {}
|
|
if vertical:
|
|
for i in range(len(names)):
|
|
line_offset = offset + vector(i*pitch,0)
|
|
if make_pins:
|
|
self.add_layout_pin(text=names[i],
|
|
layer=layer,
|
|
offset=line_offset,
|
|
height=length)
|
|
else:
|
|
self.add_rect(layer=layer,
|
|
offset=line_offset,
|
|
height=length)
|
|
line_positions[names[i]]=line_offset+vector(half_minwidth,0)
|
|
else:
|
|
for i in range(len(names)):
|
|
line_offset = offset + vector(0,i*pitch + half_minwidth)
|
|
if make_pins:
|
|
self.add_layout_pin(text=names[i],
|
|
layer=layer,
|
|
offset=line_offset,
|
|
width=length)
|
|
else:
|
|
self.add_rect(layer=layer,
|
|
offset=line_offset,
|
|
width=length)
|
|
line_positions[names[i]]=line_offset+vector(0,half_minwidth)
|
|
|
|
return line_positions
|
|
|
|
|
|
def add_control_addr_dff(self, position, rotate=0):
|
|
""" Add and place address and control flops """
|
|
self.addr_ctrl_dff_inst = self.add_inst(name="address",
|
|
mod=self.addr_ctrl_dff,
|
|
offset=position,
|
|
rotate=rotate)
|
|
# inputs, outputs/output/bar
|
|
inputs = []
|
|
outputs = []
|
|
for i in range(self.addr_size):
|
|
inputs.append("ADDR[{}]".format(i))
|
|
outputs.append("A[{}]".format(i))
|
|
|
|
for i in self.control_logic_inputs:
|
|
inputs.append(i)
|
|
outputs.append(i+"_s")
|
|
|
|
self.connect_inst(inputs + outputs + ["clk", "vdd", "gnd"])
|
|
|
|
def add_control_logic(self, position, rotate):
|
|
""" Add and place control logic """
|
|
self.control_logic_inst=self.add_inst(name="control",
|
|
mod=self.control_logic,
|
|
offset=position,
|
|
rotate=rotate)
|
|
self.connect_inst(self.control_logic_inputs + ["clk"] + self.control_logic_outputs + ["vdd", "gnd"])
|
|
|
|
|
|
def add_lvs_correspondence_points(self):
|
|
""" This adds some points for easier debugging if LVS goes wrong.
|
|
These should probably be turned off by default though, since extraction
|
|
will show these as ports in the extracted netlist.
|
|
"""
|
|
if self.num_banks==1: return
|
|
|
|
for n in self.control_bus_names:
|
|
self.add_label(text=n,
|
|
layer="metal2",
|
|
offset=self.vert_control_bus_positions[n])
|
|
for n in self.bank_sel_bus_names:
|
|
self.add_label(text=n,
|
|
layer="metal2",
|
|
offset=self.vert_control_bus_positions[n])
|
|
|
|
def add_single_bank_modules(self):
|
|
"""
|
|
This adds the moduels for a single bank SRAM with control
|
|
logic.
|
|
"""
|
|
|
|
# No orientation or offset
|
|
self.bank_inst = self.add_bank(0, [0, 0], 1, 1)
|
|
|
|
# 3/5/18 MRG: Cannot reference positions inside submodules because boundaries
|
|
# are not recomputed using instance placement. So, place the control logic such that it aligns
|
|
# with the top of the SRAM.
|
|
control_gap = 2*self.m3_width
|
|
control_pos = vector(-control_gap,
|
|
self.bank.height-self.control_logic.width)
|
|
self.add_control_logic(position=control_pos, rotate=90)
|
|
|
|
addr_pos = vector(self.control_logic_inst.lx(),
|
|
2*self.supply_rail_pitch)
|
|
self.add_control_addr_dff(addr_pos)
|
|
|
|
self.width = self.bank.width + self.control_logic.height + control_gap
|
|
self.height = self.bank.height
|
|
|
|
def add_single_bank_pins(self):
|
|
"""
|
|
Add the top-level pins for a single bank SRAM with control.
|
|
"""
|
|
|
|
for i in range(self.word_size):
|
|
self.copy_layout_pin(self.bank_inst, "DATA[{}]".format(i))
|
|
|
|
for i in range(self.addr_size):
|
|
self.copy_layout_pin(self.bank_inst, "A[{}]".format(i))
|
|
|
|
for (old,new) in zip(["csb","web","oeb","clk"],["CSb","WEb","OEb","clk"]):
|
|
self.copy_layout_pin(self.control_logic_inst, old, new)
|
|
|
|
self.copy_layout_pin(self.bank_inst, "vdd")
|
|
self.copy_layout_pin(self.bank_inst, "gnd")
|
|
|
|
|
|
def add_two_banks(self):
|
|
# Placement of bank 0 (left)
|
|
bank_position_0 = vector(self.bank.width,
|
|
self.bank.height)
|
|
self.bank_inst=[self.add_bank(0, bank_position_0, -1, -1)]
|
|
|
|
# Placement of bank 1 (right)
|
|
x_off = self.bank.width + self.vertical_bus_width + 2*self.bank_to_bus_distance
|
|
bank_position_1 = vector(x_off, bank_position_0.y)
|
|
self.bank_inst.append(self.add_bank(1, bank_position_1, -1, 1))
|
|
|
|
|
|
def add_four_banks(self):
|
|
|
|
# Placement of bank 0 (upper left)
|
|
bank_position_0 = vector(self.bank.width,
|
|
self.bank.height + self.data_bus_height + 2*self.bank_to_bus_distance)
|
|
self.bank_inst=[self.add_bank(0, bank_position_0, 1, -1)]
|
|
|
|
# Placement of bank 1 (upper right)
|
|
x_off = self.bank.width + self.vertical_bus_width + 2*self.bank_to_bus_distance
|
|
bank_position_1 = vector(x_off, bank_position_0.y)
|
|
self.bank_inst.append(self.add_bank(1, bank_position_1, 1, 1))
|
|
|
|
# Placement of bank 2 (bottom left)
|
|
y_off = self.bank.height
|
|
bank_position_2 = vector(bank_position_0.x, y_off)
|
|
self.bank_inst.append(self.add_bank(2, bank_position_2, -1, -1))
|
|
|
|
# Placement of bank 3 (bottom right)
|
|
bank_position_3 = vector(bank_position_1.x, bank_position_2.y)
|
|
self.bank_inst.append(self.add_bank(3, bank_position_3, -1, 1))
|
|
|
|
|
|
def connect_rail_from_left_m2m3(self, src_pin, dest_pin):
|
|
""" Helper routine to connect an unrotated/mirrored oriented instance to the rails """
|
|
in_pos = src_pin.rc()
|
|
out_pos = vector(dest_pin.cx(), in_pos.y)
|
|
self.add_wire(("metal3","via2","metal2"),[in_pos, out_pos, out_pos - vector(0,self.m2_pitch)])
|
|
self.add_via(layers=("metal2","via2","metal3"),
|
|
offset=src_pin.lr() - self.m2m3_offset_fix,
|
|
rotate=90)
|
|
|
|
def connect_rail_from_left_m2m1(self, src_pin, dest_pin):
|
|
""" Helper routine to connect an unrotated/mirrored oriented instance to the rails """
|
|
in_pos = src_pin.rc()
|
|
out_pos = vector(dest_pin.cx(), in_pos.y)
|
|
self.add_wire(("metal2","via1","metal1"),[in_pos, out_pos, out_pos - vector(0,self.m2_pitch)])
|
|
|
|
def route_single_bank(self):
|
|
""" Route a single bank SRAM """
|
|
for n in self.control_logic_outputs:
|
|
src_pin = self.control_logic_inst.get_pin(n)
|
|
dest_pin = self.bank_inst.get_pin(n)
|
|
self.connect_rail_from_left_m2m3(src_pin, dest_pin)
|
|
|
|
|
|
# Find the left-most metal2 rails
|
|
leftmost_vdd_rail = None
|
|
for vdd_pin in self.bank_inst.get_pins("vdd"):
|
|
if vdd_pin.layer != "metal2":
|
|
continue
|
|
if leftmost_vdd_rail == None or vdd_pin.lx() < leftmost_vdd_rail.lx():
|
|
leftmost_vdd_rail = vdd_pin
|
|
leftmost_gnd_rail = None
|
|
for gnd_pin in self.bank_inst.get_pins("gnd"):
|
|
if gnd_pin.layer != "metal2":
|
|
continue
|
|
if leftmost_gnd_rail == None or gnd_pin.lx() < leftmost_gnd_rail.lx():
|
|
leftmost_gnd_rail = gnd_pin
|
|
|
|
|
|
src_pins = self.control_logic_inst.get_pins("vdd")
|
|
for src_pin in src_pins:
|
|
if src_pin.layer != "metal2":
|
|
continue
|
|
self.connect_rail_from_left_m2m3(src_pin,leftmost_vdd_rail)
|
|
|
|
src_pins = self.control_logic_inst.get_pins("gnd")
|
|
for src_pin in src_pins:
|
|
if src_pin.layer != "metal2":
|
|
continue
|
|
self.add_path("metal2", [src_pin.rc(), vector(leftmost_gnd_rail.cx(), src_pin.cy())])
|
|
|
|
|
|
|
|
def sp_write(self, sp_name):
|
|
# Write the entire spice of the object to the file
|
|
############################################################
|
|
# Spice circuit
|
|
############################################################
|
|
sp = open(sp_name, 'w')
|
|
|
|
sp.write("**************************************************\n")
|
|
sp.write("* OpenRAM generated memory.\n")
|
|
sp.write("* Words: {}\n".format(self.num_words))
|
|
sp.write("* Data bits: {}\n".format(self.word_size))
|
|
sp.write("* Banks: {}\n".format(self.num_banks))
|
|
sp.write("* Column mux: {}:1\n".format(self.words_per_row))
|
|
sp.write("**************************************************\n")
|
|
# This causes unit test mismatch
|
|
# sp.write("* Created: {0}\n".format(datetime.datetime.now()))
|
|
# sp.write("* User: {0}\n".format(getpass.getuser()))
|
|
# sp.write(".global {0} {1}\n".format(spice["vdd_name"],
|
|
# spice["gnd_name"]))
|
|
usedMODS = list()
|
|
self.sp_write_file(sp, usedMODS)
|
|
del usedMODS
|
|
sp.close()
|
|
|
|
def analytical_delay(self,slew,load):
|
|
""" LH and HL are the same in analytical model. """
|
|
return self.bank.analytical_delay(slew,load)
|
|
|
|
def save_output(self):
|
|
""" Save all the output files while reporting time to do it as well. """
|
|
|
|
# Save the spice file
|
|
start_time = datetime.datetime.now()
|
|
spname = OPTS.output_path + self.name + ".sp"
|
|
print("SP: Writing to {0}".format(spname))
|
|
self.sp_write(spname)
|
|
print_time("Spice writing", datetime.datetime.now(), start_time)
|
|
|
|
# Save the extracted spice file
|
|
if OPTS.use_pex:
|
|
start_time = datetime.datetime.now()
|
|
# Output the extracted design if requested
|
|
sp_file = OPTS.output_path + "temp_pex.sp"
|
|
verify.run_pex(self.name, gdsname, spname, output=sp_file)
|
|
print_time("Extraction", datetime.datetime.now(), start_time)
|
|
else:
|
|
# Use generated spice file for characterization
|
|
sp_file = spname
|
|
|
|
# Characterize the design
|
|
start_time = datetime.datetime.now()
|
|
from characterizer import lib
|
|
print("LIB: Characterizing... ")
|
|
if OPTS.analytical_delay:
|
|
print("Using analytical delay models (no characterization)")
|
|
else:
|
|
if OPTS.spice_name!="":
|
|
print("Performing simulation-based characterization with {}".format(OPTS.spice_name))
|
|
if OPTS.trim_netlist:
|
|
print("Trimming netlist to speed up characterization.")
|
|
lib.lib(out_dir=OPTS.output_path, sram=self, sp_file=sp_file)
|
|
print_time("Characterization", datetime.datetime.now(), start_time)
|
|
|
|
# Write the layout
|
|
start_time = datetime.datetime.now()
|
|
gdsname = OPTS.output_path + self.name + ".gds"
|
|
print("GDS: Writing to {0}".format(gdsname))
|
|
self.gds_write(gdsname)
|
|
print_time("GDS", datetime.datetime.now(), start_time)
|
|
|
|
# Create a LEF physical model
|
|
start_time = datetime.datetime.now()
|
|
lefname = OPTS.output_path + self.name + ".lef"
|
|
print("LEF: Writing to {0}".format(lefname))
|
|
self.lef_write(lefname)
|
|
print_time("LEF", datetime.datetime.now(), start_time)
|
|
|
|
# Write a verilog model
|
|
start_time = datetime.datetime.now()
|
|
vname = OPTS.output_path + self.name + ".v"
|
|
print("Verilog: Writing to {0}".format(vname))
|
|
self.verilog_write(vname)
|
|
print_time("Verilog", datetime.datetime.now(), start_time)
|