From 50d3b4cb8d304e86c579345b5c84cf964ddc8792 Mon Sep 17 00:00:00 2001 From: Hunter Nichols Date: Tue, 19 Mar 2019 15:03:57 -0700 Subject: [PATCH 1/9] Added some bitline measures to the model_checker --- compiler/characterizer/model_check.py | 42 ++++++++++++++++++++++----- 1 file changed, 35 insertions(+), 7 deletions(-) diff --git a/compiler/characterizer/model_check.py b/compiler/characterizer/model_check.py index 12bc5d58..f9c8a296 100644 --- a/compiler/characterizer/model_check.py +++ b/compiler/characterizer/model_check.py @@ -27,6 +27,7 @@ class model_check(delay): self.wl_meas_name, self.wl_model_name = "wl_measures", "wl_model" self.sae_meas_name, self.sae_model_name = "sae_measures", "sae_model" self.wl_slew_name, self.sae_slew_name = "wl_slews", "sae_slews" + self.bl_meas_name, self.bl_slew_name = "bl_measures", "bl_slews" def create_measurement_names(self): """Create measurement names. The names themselves currently define the type of measurement""" @@ -49,6 +50,8 @@ class model_check(delay): self.rbl_slew_meas_names = ["slew_rbl_gated_clk_bar","slew_gated_clk_nand", "slew_delay_chain_in"]+dc_slew_names self.sae_slew_meas_names = ["slew_replica_bl0", "slew_pre_sen"]+sen_driver_slew_names+["slew_sen"] + self.bitline_meas_names = ["delay_wl_to_bl", "delay_bl_to_dout"] + def create_signal_names(self): """Creates list of the signal names used in the spice file along the wl and sen paths. Names are re-harded coded here; i.e. the names are hardcoded in most of OpenRAM and are @@ -73,14 +76,20 @@ class model_check(delay): self.sae_signal_names = ["Xsram.Xcontrol0.Xreplica_bitline.bl0_0", "Xsram.Xcontrol0.pre_s_en"]+\ sen_driver_signals+\ ["Xsram.s_en0"] + + dout_name = "{0}{1}_{2}".format(self.dout_name,"{}",self.probe_data) #Empty values are the port and probe data bit + self.bl_signal_names = ["Xsram.Xbank0.wl_{}".format(self.wordline_row),\ + "Xsram.Xbank0.bl_{}".format(self.bitline_column),\ + dout_name] def create_measurement_objects(self): """Create the measurements used for read and write ports""" - self.create_wordline_measurement_objects() - self.create_sae_measurement_objects() - self.all_measures = self.wl_meas_objs+self.sae_meas_objs + self.create_wordline_meas_objs() + self.create_sae_meas_objs() + self.create_bl_meas_objs() + self.all_measures = self.wl_meas_objs+self.sae_meas_objs+self.bl_meas_objs - def create_wordline_measurement_objects(self): + def create_wordline_meas_objs(self): """Create the measurements to measure the wordline path from the gated_clk_bar signal""" self.wl_meas_objs = [] trig_dir = "RISE" @@ -102,7 +111,19 @@ class model_check(delay): targ_dir = temp_dir self.wl_meas_objs.append(slew_measure(self.wl_slew_meas_names[-1], self.wl_signal_names[-1], trig_dir, measure_scale=1e9)) - def create_sae_measurement_objects(self): + def create_bl_meas_objs(self): + """Create the measurements to measure the bitline to dout, static stages""" + #Bitline has slightly different measurements, objects appends hardcoded. + self.bl_meas_objs = [] + trig_dir, targ_dir = "RISE", "FALL" #Only check read 0 + self.bl_meas_objs.append(delay_measure(self.bitline_meas_names[0], + self.bl_signal_names[0], + self.bl_signal_names[-1], + trig_dir, + targ_dir, + measure_scale=1e9)) + + def create_sae_meas_objs(self): """Create the measurements to measure the sense amp enable path from the gated_clk_bar signal. The RBL splits this path into two.""" self.sae_meas_objs = [] @@ -213,6 +234,8 @@ class model_check(delay): wl_slew_result = [[] for i in self.all_ports] sae_delay_result = [[] for i in self.all_ports] sae_slew_result = [[] for i in self.all_ports] + bl_delay_result = [[] for i in self.all_ports] + bl_slew_result = [[] for i in self.all_ports] # Checking from not data_value to data_value self.write_delay_stimulus() @@ -223,7 +246,8 @@ class model_check(delay): #Parse and check the voltage measurements wl_delay_result[port], wl_slew_result[port] = self.get_measurement_values(self.wl_meas_objs, port) sae_delay_result[port], sae_slew_result[port] = self.get_measurement_values(self.sae_meas_objs, port) - return (True,wl_delay_result, sae_delay_result, wl_slew_result, sae_slew_result) + bl_delay_result[port], bl_slew_result[port] = self.get_measurement_values(self.bl_meas_objs, port) + return (True,wl_delay_result, sae_delay_result, wl_slew_result, sae_slew_result, bl_delay_result, bl_slew_result) def get_model_delays(self, port): """Get model delays based on port. Currently assumes single RW port.""" @@ -306,7 +330,7 @@ class model_check(delay): self.targ_read_ports = [read_port] self.targ_write_ports = [self.write_ports[0]] debug.info(1,"Model test: corner {}".format(self.corner)) - (success, wl_delays, sae_delays, wl_slews, sae_slews)=self.run_delay_simulation() + (success, wl_delays, sae_delays, wl_slews, sae_slews, bl_delays, bl_slews)=self.run_delay_simulation() debug.check(success, "Model measurements Failed: period={}".format(self.period)) wl_model_delays, sae_model_delays = self.get_model_delays(read_port) @@ -316,6 +340,7 @@ class model_check(delay): debug.info(1,"Measured SAE delays (ns):\n\t {}".format(sae_delays[read_port])) debug.info(1,"SAE model delays:\n\t {}".format(sae_model_delays)) debug.info(1,"Measured SAE slews:\n\t {}".format(sae_slews[read_port])) + debug.info(1,"Measured Bitline delays (ns):\n\t {}".format(bl_delays[read_port])) data_dict[self.wl_meas_name] = wl_delays[read_port] data_dict[self.wl_model_name] = wl_model_delays @@ -323,6 +348,7 @@ class model_check(delay): data_dict[self.sae_model_name] = sae_model_delays data_dict[self.wl_slew_name] = wl_slews[read_port] data_dict[self.sae_slew_name] = sae_slews[read_port] + data_dict[self.bl_meas_name] = bl_delays[read_port] #Some evaluations of the model and measured values # debug.info(1, "Comparing wordline measurements and model.") @@ -342,6 +368,8 @@ class model_check(delay): name_dict[self.sae_model_name] = name_dict["sae_measures"] name_dict[self.wl_slew_name] = self.wl_slew_meas_names name_dict[self.sae_slew_name] = self.rbl_slew_meas_names+self.sae_slew_meas_names + name_dict[self.bl_meas_name] = self.bitline_meas_names[0:1] + #name_dict[self.wl_slew_name] = self.wl_slew_meas_names return name_dict From 97777475b4fb5a40ec12d5fd0a2398d5f61c9fc8 Mon Sep 17 00:00:00 2001 From: Hunter Nichols Date: Thu, 28 Mar 2019 17:16:23 -0700 Subject: [PATCH 2/9] Added additions to account for custom delay chains. --- compiler/characterizer/model_check.py | 99 ++++++++++++++++++++------- compiler/pgates/pdriver.py | 2 +- 2 files changed, 77 insertions(+), 24 deletions(-) diff --git a/compiler/characterizer/model_check.py b/compiler/characterizer/model_check.py index f9c8a296..ff8bbdfa 100644 --- a/compiler/characterizer/model_check.py +++ b/compiler/characterizer/model_check.py @@ -18,16 +18,18 @@ class model_check(delay): """ - def __init__(self, sram, spfile, corner): + def __init__(self, sram, spfile, corner, custom_delaychain=False): delay.__init__(self,sram,spfile,corner) self.period = tech.spice["feasible_period"] self.create_data_names() + self.custom_delaychain=custom_delaychain def create_data_names(self): self.wl_meas_name, self.wl_model_name = "wl_measures", "wl_model" self.sae_meas_name, self.sae_model_name = "sae_measures", "sae_model" self.wl_slew_name, self.sae_slew_name = "wl_slews", "sae_slews" self.bl_meas_name, self.bl_slew_name = "bl_measures", "bl_slews" + self.power_name = "total_power" def create_measurement_names(self): """Create measurement names. The names themselves currently define the type of measurement""" @@ -35,22 +37,32 @@ class model_check(delay): wl_en_driver_delay_names = ["delay_wl_en_dvr_{}".format(stage) for stage in range(1,self.get_num_wl_en_driver_stages())] wl_driver_delay_names = ["delay_wl_dvr_{}".format(stage) for stage in range(1,self.get_num_wl_driver_stages())] sen_driver_delay_names = ["delay_sen_dvr_{}".format(stage) for stage in range(1,self.get_num_sen_driver_stages())] - dc_delay_names = ["delay_delay_chain_stage_{}".format(stage) for stage in range(1,self.get_num_delay_stages()+1)] + if self.custom_delaychain: + dc_delay_names = ['delay_dc_out_final'] + else: + dc_delay_names = ["delay_delay_chain_stage_{}".format(stage) for stage in range(1,self.get_num_delay_stages()+1)] self.wl_delay_meas_names = wl_en_driver_delay_names+["delay_wl_en", "delay_wl_bar"]+wl_driver_delay_names+["delay_wl"] self.rbl_delay_meas_names = ["delay_gated_clk_nand", "delay_delay_chain_in"]+dc_delay_names self.sae_delay_meas_names = ["delay_pre_sen"]+sen_driver_delay_names+["delay_sen"] + # if self.custom_delaychain: + # self.delay_chain_indices = (len(self.rbl_delay_meas_names), len(self.rbl_delay_meas_names)+1) + # else: self.delay_chain_indices = (len(self.rbl_delay_meas_names)-len(dc_delay_names), len(self.rbl_delay_meas_names)) #Create slew measurement names wl_en_driver_slew_names = ["slew_wl_en_dvr_{}".format(stage) for stage in range(1,self.get_num_wl_en_driver_stages())] wl_driver_slew_names = ["slew_wl_dvr_{}".format(stage) for stage in range(1,self.get_num_wl_driver_stages())] sen_driver_slew_names = ["slew_sen_dvr_{}".format(stage) for stage in range(1,self.get_num_sen_driver_stages())] - dc_slew_names = ["slew_delay_chain_stage_{}".format(stage) for stage in range(1,self.get_num_delay_stages()+1)] + if self.custom_delaychain: + dc_slew_names = ['slew_dc_out_final'] + else: + dc_slew_names = ["slew_delay_chain_stage_{}".format(stage) for stage in range(1,self.get_num_delay_stages()+1)] self.wl_slew_meas_names = ["slew_wl_gated_clk_bar"]+wl_en_driver_slew_names+["slew_wl_en", "slew_wl_bar"]+wl_driver_slew_names+["slew_wl"] self.rbl_slew_meas_names = ["slew_rbl_gated_clk_bar","slew_gated_clk_nand", "slew_delay_chain_in"]+dc_slew_names self.sae_slew_meas_names = ["slew_replica_bl0", "slew_pre_sen"]+sen_driver_slew_names+["slew_sen"] self.bitline_meas_names = ["delay_wl_to_bl", "delay_bl_to_dout"] + self.power_meas_names = ['read0_power'] def create_signal_names(self): """Creates list of the signal names used in the spice file along the wl and sen paths. @@ -62,7 +74,10 @@ class model_check(delay): wl_en_driver_signals = ["Xsram.Xcontrol0.Xbuf_wl_en.Zb{}_int".format(stage) for stage in range(1,self.get_num_wl_en_driver_stages())] wl_driver_signals = ["Xsram.Xbank0.Xwordline_driver0.Xwl_driver_inv{}.Zb{}_int".format(self.wordline_row, stage) for stage in range(1,self.get_num_wl_driver_stages())] sen_driver_signals = ["Xsram.Xcontrol0.Xbuf_s_en.Zb{}_int".format(stage) for stage in range(1,self.get_num_sen_driver_stages())] - delay_chain_signal_names = ["Xsram.Xcontrol0.Xreplica_bitline.Xdelay_chain.dout_{}".format(stage) for stage in range(1,self.get_num_delay_stages())] + if self.custom_delaychain: + delay_chain_signal_names = [] + else: + delay_chain_signal_names = ["Xsram.Xcontrol0.Xreplica_bitline.Xdelay_chain.dout_{}".format(stage) for stage in range(1,self.get_num_delay_stages())] self.wl_signal_names = ["Xsram.Xcontrol0.gated_clk_bar"]+\ wl_en_driver_signals+\ @@ -73,6 +88,8 @@ class model_check(delay): self.rbl_en_signal_names = pre_delay_chain_names+\ delay_chain_signal_names+\ ["Xsram.Xcontrol0.Xreplica_bitline.delayed_en"] + + self.sae_signal_names = ["Xsram.Xcontrol0.Xreplica_bitline.bl0_0", "Xsram.Xcontrol0.pre_s_en"]+\ sen_driver_signals+\ ["Xsram.s_en0"] @@ -87,7 +104,13 @@ class model_check(delay): self.create_wordline_meas_objs() self.create_sae_meas_objs() self.create_bl_meas_objs() - self.all_measures = self.wl_meas_objs+self.sae_meas_objs+self.bl_meas_objs + self.create_power_meas_objs() + self.all_measures = self.wl_meas_objs+self.sae_meas_objs+self.bl_meas_objs+self.power_meas_objs + + def create_power_meas_objs(self): + """Create power measurement object. Only one.""" + self.power_meas_objs = [] + self.power_meas_objs.append(power_measure(self.power_meas_names[0], "FALL", measure_scale=1e3)) def create_wordline_meas_objs(self): """Create the measurements to measure the wordline path from the gated_clk_bar signal""" @@ -144,6 +167,13 @@ class model_check(delay): temp_dir = trig_dir trig_dir = targ_dir targ_dir = temp_dir + if self.custom_delaychain: #Hack for custom delay chains + self.sae_meas_objs[-2] = delay_measure(self.rbl_delay_meas_names[-1], + self.rbl_en_signal_names[-2], + self.rbl_en_signal_names[-1], + "RISE", + "RISE", + measure_scale=1e9) self.sae_meas_objs.append(slew_measure(self.rbl_slew_meas_names[-1], self.rbl_en_signal_names[-1], trig_dir, @@ -152,7 +182,6 @@ class model_check(delay): #Add measurements from rbl_out to sae. Trigger directions do not invert from previous stage due to RBL. trig_dir = "FALL" targ_dir = "RISE" - #Add measurements from gated_clk_bar to RBL for i in range(1, len(self.sae_signal_names)): self.sae_meas_objs.append(delay_measure(self.sae_delay_meas_names[i-1], self.sae_signal_names[i-1], @@ -190,10 +219,22 @@ class model_check(delay): or port to port (time delays)""" #Return value is intended to match the delay measure format: trig_td, targ_td, vdd, port #Assuming only read 0 for now - if not (type(measure_obj) is delay_measure or type(measure_obj) is slew_measure): + debug.info(3,"Power measurement={}".format(measure_obj)) + if (type(measure_obj) is delay_measure or type(measure_obj) is slew_measure): + meas_cycle_delay = self.cycle_times[self.measure_cycles[port]["read0"]] + self.period/2 + return (meas_cycle_delay, meas_cycle_delay, self.vdd_voltage, port) + elif type(measure_obj) is power_measure: + return self.get_power_measure_variants(port, measure_obj, "read") + else: debug.error("Measurement not recognized by the model checker.",1) - meas_cycle_delay = self.cycle_times[self.measure_cycles[port]["read0"]] + self.period/2 - return (meas_cycle_delay, meas_cycle_delay, self.vdd_voltage, port) + + def get_power_measure_variants(self, port, power_obj, operation): + """Get the measurement values that can either vary port to port (time delays)""" + #Return value is intended to match the power measure format: t_initial, t_final, port + t_initial = self.cycle_times[self.measure_cycles[port]["read0"]] + t_final = self.cycle_times[self.measure_cycles[port]["read0"]+1] + + return (t_initial, t_final, port) def write_measures_read_port(self, port): """ @@ -207,7 +248,8 @@ class model_check(delay): def get_measurement_values(self, meas_objs, port): """Gets the delays and slews from a specified port from the spice output file and returns them as lists.""" delay_meas_list = [] - slew_meas_list = [] + slew_meas_list = [] + power_meas_list=[] for measure in meas_objs: measure_value = measure.retrieve_measure(port=port) if type(measure_value) != float: @@ -216,9 +258,11 @@ class model_check(delay): delay_meas_list.append(measure_value) elif type(measure)is slew_measure: slew_meas_list.append(measure_value) + elif type(measure)is power_measure: + power_meas_list.append(measure_value) else: debug.error("Measurement object not recognized.",1) - return delay_meas_list, slew_meas_list + return delay_meas_list, slew_meas_list,power_meas_list def run_delay_simulation(self): """ @@ -236,6 +280,7 @@ class model_check(delay): sae_slew_result = [[] for i in self.all_ports] bl_delay_result = [[] for i in self.all_ports] bl_slew_result = [[] for i in self.all_ports] + power_result = [[] for i in self.all_ports] # Checking from not data_value to data_value self.write_delay_stimulus() @@ -244,10 +289,11 @@ class model_check(delay): #Retrieve the results from the output file for port in self.targ_read_ports: #Parse and check the voltage measurements - wl_delay_result[port], wl_slew_result[port] = self.get_measurement_values(self.wl_meas_objs, port) - sae_delay_result[port], sae_slew_result[port] = self.get_measurement_values(self.sae_meas_objs, port) - bl_delay_result[port], bl_slew_result[port] = self.get_measurement_values(self.bl_meas_objs, port) - return (True,wl_delay_result, sae_delay_result, wl_slew_result, sae_slew_result, bl_delay_result, bl_slew_result) + wl_delay_result[port], wl_slew_result[port],_ = self.get_measurement_values(self.wl_meas_objs, port) + sae_delay_result[port], sae_slew_result[port],_ = self.get_measurement_values(self.sae_meas_objs, port) + bl_delay_result[port], bl_slew_result[port],_ = self.get_measurement_values(self.bl_meas_objs, port) + _,__,power_result[port] = self.get_measurement_values(self.power_meas_objs, port) + return (True,wl_delay_result, sae_delay_result, wl_slew_result, sae_slew_result, bl_delay_result, bl_slew_result, power_result) def get_model_delays(self, port): """Get model delays based on port. Currently assumes single RW port.""" @@ -330,25 +376,28 @@ class model_check(delay): self.targ_read_ports = [read_port] self.targ_write_ports = [self.write_ports[0]] debug.info(1,"Model test: corner {}".format(self.corner)) - (success, wl_delays, sae_delays, wl_slews, sae_slews, bl_delays, bl_slews)=self.run_delay_simulation() + (success, wl_delays, sae_delays, wl_slews, sae_slews, bl_delays, bl_slews, powers)=self.run_delay_simulation() debug.check(success, "Model measurements Failed: period={}".format(self.period)) - wl_model_delays, sae_model_delays = self.get_model_delays(read_port) debug.info(1,"Measured Wordline delays (ns):\n\t {}".format(wl_delays[read_port])) - debug.info(1,"Wordline model delays:\n\t {}".format(wl_model_delays)) debug.info(1,"Measured Wordline slews:\n\t {}".format(wl_slews[read_port])) debug.info(1,"Measured SAE delays (ns):\n\t {}".format(sae_delays[read_port])) - debug.info(1,"SAE model delays:\n\t {}".format(sae_model_delays)) debug.info(1,"Measured SAE slews:\n\t {}".format(sae_slews[read_port])) debug.info(1,"Measured Bitline delays (ns):\n\t {}".format(bl_delays[read_port])) data_dict[self.wl_meas_name] = wl_delays[read_port] - data_dict[self.wl_model_name] = wl_model_delays data_dict[self.sae_meas_name] = sae_delays[read_port] - data_dict[self.sae_model_name] = sae_model_delays data_dict[self.wl_slew_name] = wl_slews[read_port] data_dict[self.sae_slew_name] = sae_slews[read_port] data_dict[self.bl_meas_name] = bl_delays[read_port] + data_dict[self.power_name] = powers[read_port] + + if not OPTS.use_tech_delay_chain_size: #Model is not used in this case + wl_model_delays, sae_model_delays = self.get_model_delays(read_port) + debug.info(1,"Wordline model delays:\n\t {}".format(wl_model_delays)) + debug.info(1,"SAE model delays:\n\t {}".format(sae_model_delays)) + data_dict[self.wl_model_name] = wl_model_delays + data_dict[self.sae_model_name] = sae_model_delays #Some evaluations of the model and measured values # debug.info(1, "Comparing wordline measurements and model.") @@ -363,13 +412,17 @@ class model_check(delay): name_dict = {} #Signal names are more descriptive than the measurement names, first value trimmed to match size of measurements names. name_dict[self.wl_meas_name] = self.wl_signal_names[1:] - name_dict[self.wl_model_name] = name_dict["wl_measures"] #model uses same names as measured. name_dict[self.sae_meas_name] = self.rbl_en_signal_names[1:]+self.sae_signal_names[1:] - name_dict[self.sae_model_name] = name_dict["sae_measures"] name_dict[self.wl_slew_name] = self.wl_slew_meas_names name_dict[self.sae_slew_name] = self.rbl_slew_meas_names+self.sae_slew_meas_names name_dict[self.bl_meas_name] = self.bitline_meas_names[0:1] + name_dict[self.power_name] = self.power_meas_names #name_dict[self.wl_slew_name] = self.wl_slew_meas_names + + if not OPTS.use_tech_delay_chain_size: + name_dict[self.wl_model_name] = name_dict["wl_measures"] #model uses same names as measured. + name_dict[self.sae_model_name] = name_dict["sae_measures"] + return name_dict diff --git a/compiler/pgates/pdriver.py b/compiler/pgates/pdriver.py index daf4d334..5b4a6c9a 100644 --- a/compiler/pgates/pdriver.py +++ b/compiler/pgates/pdriver.py @@ -11,7 +11,7 @@ class pdriver(pgate.pgate): """ This instantiates an even or odd number of inverters sized for driving a load. """ - def __init__(self, name, neg_polarity=False, fanout=0, size_list=None, height=None): + def __init__(self, name, neg_polarity=False, fanout=1, size_list=None, height=None): self.stage_effort = 3 self.height = height From f6eefc1728042747ee658db591c9195a7af468f7 Mon Sep 17 00:00:00 2001 From: Hunter Nichols Date: Tue, 2 Apr 2019 01:09:31 -0700 Subject: [PATCH 3/9] Added updated analytical characterization with combined models --- compiler/bitcells/bitcell.py | 28 ++++--- compiler/characterizer/logical_effort.py | 33 +++++--- compiler/modules/bank.py | 74 +++++++++++------ compiler/modules/bitcell_array.py | 42 ++++++---- compiler/modules/control_logic.py | 79 +++++++++++++++---- compiler/modules/sense_amp.py | 14 ++-- compiler/modules/sense_amp_array.py | 4 +- .../modules/single_level_column_mux_array.py | 7 ++ compiler/pgates/pand2.py | 5 ++ compiler/pgates/single_level_column_mux.py | 6 +- compiler/sram_base.py | 33 +++++++- compiler/tests/23_lib_sram_model_test.py | 2 +- technology/freepdk45/tech/tech.py | 3 + technology/scn4m_subm/tech/tech.py | 3 + 14 files changed, 240 insertions(+), 93 deletions(-) diff --git a/compiler/bitcells/bitcell.py b/compiler/bitcells/bitcell.py index ed1647a8..d5712d7f 100644 --- a/compiler/bitcells/bitcell.py +++ b/compiler/bitcells/bitcell.py @@ -2,6 +2,7 @@ import design import debug import utils from tech import GDS,layer,parameter,drc +import logical_effort class bitcell(design.design): """ @@ -24,18 +25,23 @@ class bitcell(design.design): self.height = bitcell.height self.pin_map = bitcell.pin_map - def analytical_delay(self, corner, slew, load=0, swing = 0.5): - # delay of bit cell is not like a driver(from WL) - # so the slew used should be 0 - # it should not be slew dependent? - # because the value is there - # the delay is only over half transsmission gate - from tech import spice - r = spice["min_tx_r"]*3 - c_para = spice["min_tx_drain_c"] - result = self.cal_delay_with_rc(corner, r = r, c = c_para+load, slew = slew, swing = swing) - return result + # def analytical_delay(self, corner, slew, load=0, swing = 0.5): + # # delay of bit cell is not like a driver(from WL) + # # so the slew used should be 0 + # # it should not be slew dependent? + # # because the value is there + # # the delay is only over half transsmission gate + # from tech import spice + # r = spice["min_tx_r"]*3 + # c_para = spice["min_tx_drain_c"] + # result = self.cal_delay_with_rc(corner, r = r, c = c_para+load, slew = slew, swing = swing) + # return result + def analytical_delay(self, corner, slew, load=0, swing = 0.5): + parasitic_delay = 1 + size = 0.5 #This accounts for bitline being drained thought the access TX and internal node + cin = 3 #Assumes always a minimum sizes inverter. Could be specified in the tech.py file. + return logical_effort.logical_effort('bitline', size, cin, load, parasitic_delay, False) def list_bitcell_pins(self, col, row): """ Creates a list of connections in the bitcell, indexed by column and row, for instance use in bitcell_array """ diff --git a/compiler/characterizer/logical_effort.py b/compiler/characterizer/logical_effort.py index c80e69a2..97c10d51 100644 --- a/compiler/characterizer/logical_effort.py +++ b/compiler/characterizer/logical_effort.py @@ -9,6 +9,7 @@ class logical_effort(): beta = parameter["beta"] min_inv_cin = 1+beta pinv=parameter["min_inv_para_delay"] + tau = parameter['le_tau'] def __init__(self, name, size, cin, cout, parasitic, out_is_rise=True): self.name = name @@ -30,30 +31,40 @@ class logical_effort(): def get_stage_effort(self): return self.logical_effort*self.eletrical_effort - def get_parasitic_delay(self, pinv): - return pinv * self.parasitic_scale + def get_parasitic_delay(self): + return logical_effort.pinv * self.parasitic_scale - def get_stage_delay(self, pinv): - return self.get_stage_effort()+self.get_parasitic_delay(pinv) + def get_stage_delay(self): + return self.get_stage_effort()+self.get_parasitic_delay() -def calculate_delays(stage_effort_list, pinv): + def get_absolute_delay(self): + return logical_effort.tau*self.get_stage_delay() + +def calculate_delays(stage_effort_list): """Convert stage effort objects to list of delay values""" - return [stage.get_stage_delay(pinv) for stage in stage_effort_list] + return [stage.get_stage_delay() for stage in stage_effort_list] -def calculate_relative_delay(stage_effort_list, pinv=parameter["min_inv_para_delay"]): +def calculate_relative_delay(stage_effort_list): """Calculates the total delay of a given delay path made of a list of logical effort objects.""" - total_rise_delay, total_fall_delay = calculate_relative_rise_fall_delays(stage_effort_list, pinv) + total_rise_delay, total_fall_delay = calculate_relative_rise_fall_delays(stage_effort_list) return total_rise_delay + total_fall_delay + +def calculate_absolute_delay(stage_effort_list): + """Calculates the total delay of a given delay path made of a list of logical effort objects.""" + total_delay = 0 + for stage in stage_effort_list: + total_delay+=stage.get_absolute_delay() + return total_delay -def calculate_relative_rise_fall_delays(stage_effort_list, pinv=parameter["min_inv_para_delay"]): +def calculate_relative_rise_fall_delays(stage_effort_list): """Calculates the rise/fall delays of a given delay path made of a list of logical effort objects.""" debug.info(2, "Calculating rise/fall relative delays") total_rise_delay, total_fall_delay = 0,0 for stage in stage_effort_list: debug.info(2, stage) if stage.is_rise: - total_rise_delay += stage.get_stage_delay(pinv) + total_rise_delay += stage.get_stage_delay() else: - total_fall_delay += stage.get_stage_delay(pinv) + total_fall_delay += stage.get_stage_delay() return total_rise_delay, total_fall_delay \ No newline at end of file diff --git a/compiler/modules/bank.py b/compiler/modules/bank.py index 7eddc3bb..e6d18e0b 100644 --- a/compiler/modules/bank.py +++ b/compiler/modules/bank.py @@ -1216,36 +1216,62 @@ class bank(design.design): rotate=90) - def analytical_delay(self, corner, slew, load): - """ return analytical delay of the bank""" - results = [] + # def analytical_delay(self, corner, slew, load): + # """ return analytical delay of the bank""" + # results = [] - decoder_delay = self.row_decoder.analytical_delay(corner, slew, self.wordline_driver.input_load()) + # decoder_delay = self.row_decoder.analytical_delay(corner, slew, self.wordline_driver.input_load()) - word_driver_delay = self.wordline_driver.analytical_delay(corner, - decoder_delay.slew, - self.bitcell_array.input_load()) + # word_driver_delay = self.wordline_driver.analytical_delay(corner, + # decoder_delay.slew, + # self.bitcell_array.input_load()) + + # #FIXME: Array delay is the same for every port. + # bitcell_array_delay = self.bitcell_array.analytical_delay(corner, word_driver_delay.slew) + + # #This also essentially creates the same delay for each port. Good structure, no substance + # for port in self.all_ports: + # if self.words_per_row > 1: + # column_mux_delay = self.column_mux_array[port].analytical_delay(corner, + # bitcell_array_delay.slew, + # self.sense_amp_array.input_load()) + # else: + # column_mux_delay = self.return_delay(delay = 0.0, slew=word_driver_delay.slew) + + # bl_t_data_out_delay = self.sense_amp_array.analytical_delay(corner, + # column_mux_delay.slew, + # self.bitcell_array.output_load()) + # # output load of bitcell_array is set to be only small part of bl for sense amp. + # results.append(decoder_delay + word_driver_delay + bitcell_array_delay + column_mux_delay + bl_t_data_out_delay) + + # return results + + def analytical_delay(self, corner, slew, load): + """ return analytical delay of the bank. This will track the clock to output path""" + #FIXME: This delay is determined in the control logic. Should be moved here. + # word_driver_delay = self.wordline_driver.analytical_delay(corner, + # slew, + # self.bitcell_array.input_load()) #FIXME: Array delay is the same for every port. - bitcell_array_delay = self.bitcell_array.analytical_delay(corner, word_driver_delay.slew) + word_driver_slew = 0 + bitcell_array_delay = self.bitcell_array.analytical_delay(corner, word_driver_slew) #This also essentially creates the same delay for each port. Good structure, no substance - for port in self.all_ports: - if self.words_per_row > 1: - column_mux_delay = self.column_mux_array[port].analytical_delay(corner, - bitcell_array_delay.slew, - self.sense_amp_array.input_load()) - else: - column_mux_delay = self.return_delay(delay = 0.0, slew=word_driver_delay.slew) - - bl_t_data_out_delay = self.sense_amp_array.analytical_delay(corner, - column_mux_delay.slew, - self.bitcell_array.output_load()) - # output load of bitcell_array is set to be only small part of bl for sense amp. - results.append(decoder_delay + word_driver_delay + bitcell_array_delay + column_mux_delay + bl_t_data_out_delay) - - return results - + if self.words_per_row > 1: + column_mux_delay = self.column_mux_array[port].analytical_delay(corner, + bitcell_array_delay.slew, + self.sense_amp_array.input_load()) + else: + column_mux_delay = [] + + column_mux_slew = 0 + sense_amp_delay = self.sense_amp_array.analytical_delay(corner, + column_mux_slew, + self.bitcell_array.output_load()) + # output load of bitcell_array is set to be only small part of bl for sense amp. + return bitcell_array_delay + column_mux_delay + sense_amp_delay + def determine_wordline_stage_efforts(self, external_cout, inp_is_rise=True): """Get the all the stage efforts for each stage in the path within the bank clk_buf to a wordline""" #Decoder is assumed to have settled before the negative edge of the clock. Delay model relies on this assumption diff --git a/compiler/modules/bitcell_array.py b/compiler/modules/bitcell_array.py index ea8fc3f2..6aecfd6b 100644 --- a/compiler/modules/bitcell_array.py +++ b/compiler/modules/bitcell_array.py @@ -4,6 +4,7 @@ from tech import drc, spice from vector import vector from globals import OPTS from sram_factory import factory +import logical_effort class bitcell_array(design.design): """ @@ -130,23 +131,32 @@ class bitcell_array(design.design): self.add_power_pin(pin_name, pin.center(), 0, pin.layer) + # def analytical_delay(self, corner, slew, load=0): + # from tech import drc + # wl_wire = self.gen_wl_wire() + # wl_wire.return_delay_over_wire(slew) + + # wl_to_cell_delay = wl_wire.return_delay_over_wire(slew) + # # hypothetical delay from cell to bl end without sense amp + # bl_wire = self.gen_bl_wire() + # cell_load = 2 * bl_wire.return_input_cap() # we ingore the wire r + # # hence just use the whole c + # bl_swing = 0.1 + # cell_delay = self.cell.analytical_delay(corner, wl_to_cell_delay.slew, cell_load, swing = bl_swing) + + # #we do not consider the delay over the wire for now + # return self.return_delay(cell_delay.delay+wl_to_cell_delay.delay, + # wl_to_cell_delay.slew) + def analytical_delay(self, corner, slew, load=0): - from tech import drc - wl_wire = self.gen_wl_wire() - wl_wire.return_delay_over_wire(slew) - - wl_to_cell_delay = wl_wire.return_delay_over_wire(slew) - # hypothetical delay from cell to bl end without sense amp - bl_wire = self.gen_bl_wire() - cell_load = 2 * bl_wire.return_input_cap() # we ingore the wire r - # hence just use the whole c - bl_swing = 0.1 - cell_delay = self.cell.analytical_delay(corner, wl_to_cell_delay.slew, cell_load, swing = bl_swing) - - #we do not consider the delay over the wire for now - return self.return_delay(cell_delay.delay+wl_to_cell_delay.delay, - wl_to_cell_delay.slew) - + """Returns relative delay of the bitline in the bitcell array""" + #The load being driven/drained is mostly the bitline but could include the sense amp or the column mux. + #The load from the bitlines is due to the drain capacitances from all the other bitlines and wire parasitics. + drain_parasitics = .5 #each bitcell adds half a parasitic to the delay + wire_parasitics = .05 * drain_parasitics #Wires add 5% to this. + bitline_load = (drain_parasitics+wire_parasitics)*self.row_size * logical_effort.logical_effort.pinv + return [self.cell.analytical_delay(corner, slew, load+bitline_load)] + def analytical_power(self, corner, load): """Power of Bitcell array and bitline in nW.""" from tech import drc, parameter diff --git a/compiler/modules/control_logic.py b/compiler/modules/control_logic.py index b8532ee9..a9b4a56b 100644 --- a/compiler/modules/control_logic.py +++ b/compiler/modules/control_logic.py @@ -33,10 +33,10 @@ class control_logic(design.design): self.num_words = num_rows*words_per_row self.enable_delay_chain_resizing = True + self.inv_parasitic_delay = logical_effort.logical_effort.pinv #Determines how much larger the sen delay should be. Accounts for possible error in model. self.wl_timing_tolerance = 1 - self.parasitic_inv_delay = parameter["min_inv_para_delay"] self.wl_stage_efforts = None self.sen_stage_efforts = None @@ -219,7 +219,7 @@ class control_logic(design.design): def get_dynamic_delay_chain_size(self, previous_stages, previous_fanout): """Determine the size of the delay chain used for the Sense Amp Enable using path delays""" from math import ceil - previous_delay_chain_delay = (previous_fanout+1+self.parasitic_inv_delay)*previous_stages + previous_delay_chain_delay = (previous_fanout+1+self.inv_parasitic_delay)*previous_stages debug.info(2, "Previous delay chain produced {} delay units".format(previous_delay_chain_delay)) delay_fanout = 3 # This can be anything >=2 @@ -227,7 +227,7 @@ class control_logic(design.design): #inverter adds 1 unit of delay (due to minimum size). This also depends on the pinv value required_delay = self.wl_delay*self.wl_timing_tolerance - (self.sen_delay-previous_delay_chain_delay) debug.check(required_delay > 0, "Cannot size delay chain to have negative delay") - delay_stages = ceil(required_delay/(delay_fanout+1+self.parasitic_inv_delay)) + delay_stages = ceil(required_delay/(delay_fanout+1+self.inv_parasitic_delay)) if delay_stages%2 == 1: #force an even number of stages. delay_stages+=1 #Fanout can be varied as well but is a little more complicated but potentially optimal. @@ -237,7 +237,7 @@ class control_logic(design.design): def get_dynamic_delay_fanout_list(self, previous_stages, previous_fanout): """Determine the size of the delay chain used for the Sense Amp Enable using path delays""" - previous_delay_chain_delay = (previous_fanout+1+self.parasitic_inv_delay)*previous_stages + previous_delay_chain_delay = (previous_fanout+1+self.inv_parasitic_delay)*previous_stages debug.info(2, "Previous delay chain produced {} delay units".format(previous_delay_chain_delay)) fanout_rise = fanout_fall = 2 # This can be anything >=2 @@ -284,9 +284,9 @@ class control_logic(design.design): def calculate_stages_with_fixed_fanout(self, required_delay, fanout): from math import ceil #Delay being negative is not an error. It implies that any amount of stages would have a negative effect on the overall delay - if required_delay <= 3+self.parasitic_inv_delay: #3 is the minimum delay per stage (with pinv=0). + if required_delay <= 3+self.inv_parasitic_delay: #3 is the minimum delay per stage (with pinv=0). return 1 - delay_stages = ceil(required_delay/(fanout+1+self.parasitic_inv_delay)) + delay_stages = ceil(required_delay/(fanout+1+self.inv_parasitic_delay)) return delay_stages def calculate_stage_list(self, total_stages, fanout_rise, fanout_fall): @@ -850,14 +850,14 @@ class control_logic(design.design): def get_delays_to_wl(self): """Get the delay (in delay units) of the clk to a wordline in the bitcell array""" debug.check(self.sram.all_mods_except_control_done, "Cannot calculate sense amp enable delay unless all module have been added.") - self.wl_stage_efforts = self.determine_wordline_stage_efforts() - clk_to_wl_rise,clk_to_wl_fall = logical_effort.calculate_relative_rise_fall_delays(self.wl_stage_efforts, self.parasitic_inv_delay) + self.wl_stage_efforts = self.get_wordline_stage_efforts() + clk_to_wl_rise,clk_to_wl_fall = logical_effort.calculate_relative_rise_fall_delays(self.wl_stage_efforts) total_delay = clk_to_wl_rise + clk_to_wl_fall debug.info(1, "Clock to wl delay is rise={:.3f}, fall={:.3f}, total={:.3f} in delay units".format(clk_to_wl_rise, clk_to_wl_fall,total_delay)) return clk_to_wl_rise,clk_to_wl_fall - def determine_wordline_stage_efforts(self): + def get_wordline_stage_efforts(self): """Follows the gated_clk_bar -> wl_en -> wordline signal for the total path efforts""" stage_effort_list = [] @@ -871,7 +871,7 @@ class control_logic(design.design): last_stage_is_rise = stage_effort_list[-1].is_rise #Then ask the sram for the other path delays (from the bank) - stage_effort_list += self.sram.determine_wordline_stage_efforts(last_stage_is_rise) + stage_effort_list += self.sram.get_wordline_stage_efforts(last_stage_is_rise) return stage_effort_list @@ -880,17 +880,15 @@ class control_logic(design.design): This does not incorporate the delay of the replica bitline. """ debug.check(self.sram.all_mods_except_control_done, "Cannot calculate sense amp enable delay unless all module have been added.") - self.sen_stage_efforts = self.determine_sa_enable_stage_efforts() - clk_to_sen_rise, clk_to_sen_fall = logical_effort.calculate_relative_rise_fall_delays(self.sen_stage_efforts, self.parasitic_inv_delay) + self.sen_stage_efforts = self.get_sa_enable_stage_efforts() + clk_to_sen_rise, clk_to_sen_fall = logical_effort.calculate_relative_rise_fall_delays(self.sen_stage_efforts) total_delay = clk_to_sen_rise + clk_to_sen_fall debug.info(1, "Clock to s_en delay is rise={:.3f}, fall={:.3f}, total={:.3f} in delay units".format(clk_to_sen_rise, clk_to_sen_fall,total_delay)) return clk_to_sen_rise, clk_to_sen_fall - def determine_sa_enable_stage_efforts(self): + def get_sa_enable_stage_efforts(self): """Follows the gated_clk_bar signal to the sense amp enable signal adding each stages stage effort to a list""" stage_effort_list = [] - #Calculate the load on clk_buf_bar - ext_clk_buf_cout = self.sram.get_clk_bar_cin() #Initial direction of clock signal for this path last_stage_rise = True @@ -917,7 +915,54 @@ class control_logic(design.design): """Gets a list of the stages and delays in order of their path.""" if self.sen_stage_efforts == None or self.wl_stage_efforts == None: debug.error("Model delays not calculated for SRAM.", 1) - wl_delays = logical_effort.calculate_delays(self.wl_stage_efforts, self.parasitic_inv_delay) - sen_delays = logical_effort.calculate_delays(self.sen_stage_efforts, self.parasitic_inv_delay) + wl_delays = logical_effort.calculate_delays(self.wl_stage_efforts) + sen_delays = logical_effort.calculate_delays(self.sen_stage_efforts) return wl_delays, sen_delays + def analytical_delay(self, corner, slew, load): + """Gets the analytical delay from clk input to wl_en output""" + stage_effort_list = [] + #Calculate the load on clk_buf_bar + ext_clk_buf_cout = self.sram.get_clk_bar_cin() + + #Operations logic starts on negative edge + last_stage_rise = False + + #First stage(s), clk -(pdriver)-> clk_buf. + clk_buf_cout = self.replica_bitline.get_en_cin() + stage_effort_list += self.clk_buf_driver.get_stage_efforts(clk_buf_cout, last_stage_rise) + last_stage_rise = stage_effort_list[-1].is_rise + + #Second stage, clk_buf -(inv)-> clk_bar + clk_bar_cout = self.and2.get_cin() + stage_effort_list += self.and2.get_stage_efforts(clk_bar_cout, last_stage_rise) + last_stage_rise = stage_effort_list[-1].is_rise + + #Third stage clk_bar -(and)-> gated_clk_bar + gated_clk_bar_cin = self.get_gated_clk_bar_cin() + stage_effort_list.append(self.inv.get_stage_effort(gated_clk_bar_cin, last_stage_rise)) + last_stage_rise = stage_effort_list[-1].is_rise + + #Stages from gated_clk_bar -------> wordline + stage_effort_list += self.get_wordline_stage_efforts() + return stage_effort_list + + def get_clk_buf_cin(self): + """Get the loads that are connected to the buffered clock. + Includes all the DFFs and some logic.""" + + #Control logic internal load + int_clk_buf_cap = self.inv.get_cin() + self.ctrl_dff_array.get_clk_cin() + self.and2.get_cin() + + #Control logic external load (in the other parts of the SRAM) + ext_clk_buf_cap = self.sram.get_clk_bar_cin() + + return int_clk_buf_cap + ext_clk_buf_cap + + def get_gated_clk_bar_cin(self): + """Get intermediates net gated_clk_bar's capacitance""" + total_cin = 0 + total_cin += self.wl_en_driver.get_cin() + if self.port_type == 'rw': + total_cin +=self.and2.get_cin() + return total_cin \ No newline at end of file diff --git a/compiler/modules/sense_amp.py b/compiler/modules/sense_amp.py index 0c959685..8d739041 100644 --- a/compiler/modules/sense_amp.py +++ b/compiler/modules/sense_amp.py @@ -2,6 +2,7 @@ import design import debug import utils from tech import GDS,layer, parameter,drc +import logical_effort class sense_amp(design.design): """ @@ -31,12 +32,13 @@ class sense_amp(design.design): bitline_pmos_size = 8 #FIXME: This should be set somewhere and referenced. Probably in tech file. return spice["min_tx_drain_c"]*(bitline_pmos_size/parameter["min_tx_size"])#ff - def analytical_delay(self, corner, slew, load=0.0): - from tech import spice - r = spice["min_tx_r"]/(10) - c_para = spice["min_tx_drain_c"] - result = self.cal_delay_with_rc(corner, r = r, c = c_para+load, slew = slew) - return self.return_delay(result.delay, result.slew) + def analytical_delay(self, corner, slew, load): + #Delay of the sense amp will depend on the size of the amp and the output load. + parasitic_delay = 1 + cin = (parameter["sa_inv_pmos_size"] + parameter["sa_inv_nmos_size"])/drc("minwidth_tx") + sa_size = parameter["sa_inv_nmos_size"]/drc("minwidth_tx") + cc_inv_cin = cin + return logical_effort.logical_effort('column_mux', sa_size, cin, load+cc_inv_cin, parasitic_delay, False) def analytical_power(self, corner, load): """Returns dynamic and leakage power. Results in nW""" diff --git a/compiler/modules/sense_amp_array.py b/compiler/modules/sense_amp_array.py index 47969fd1..83e3d34a 100644 --- a/compiler/modules/sense_amp_array.py +++ b/compiler/modules/sense_amp_array.py @@ -136,8 +136,8 @@ class sense_amp_array(design.design): def input_load(self): return self.amp.input_load() - def analytical_delay(self, corner, slew, load=0.0): - return self.amp.analytical_delay(corner, slew=slew, load=load) + def analytical_delay(self, corner, slew, load): + return [self.amp.analytical_delay(corner, slew=slew, load=load)] def get_en_cin(self): """Get the relative capacitance of all the sense amp enable connections in the array""" diff --git a/compiler/modules/single_level_column_mux_array.py b/compiler/modules/single_level_column_mux_array.py index 57d2cd54..c2414653 100644 --- a/compiler/modules/single_level_column_mux_array.py +++ b/compiler/modules/single_level_column_mux_array.py @@ -227,3 +227,10 @@ class single_level_column_mux_array(design.design): result = self.cal_delay_with_rc(corner, r = r, c = c_para+load, slew = slew, swing = volt_swing) return self.return_delay(result.delay, result.slew) + + def analytical_delay(self, corner, slew, load): + """Returns relative delay that the column mux adds""" + #Single level column mux will add parasitic loads from other mux pass transistors and the sense amp. + drain_parasitics = .5 #Assumed parasitics from unused TXs + array_load = drain_parasitics*self.words_per_row*logical_effort.pinv + return [self.mux.analytical_delay(corner, slew, load+array_load)] \ No newline at end of file diff --git a/compiler/pgates/pand2.py b/compiler/pgates/pand2.py index 54787282..c2165b20 100644 --- a/compiler/pgates/pand2.py +++ b/compiler/pgates/pand2.py @@ -125,3 +125,8 @@ class pand2(pgate.pgate): stage_effort_list.append(stage2) return stage_effort_list + + def get_cin(self): + """Return the relative input capacitance of a single input""" + return self.nand.get_cin() + \ No newline at end of file diff --git a/compiler/pgates/single_level_column_mux.py b/compiler/pgates/single_level_column_mux.py index f03a22e8..d4ff9561 100644 --- a/compiler/pgates/single_level_column_mux.py +++ b/compiler/pgates/single_level_column_mux.py @@ -180,5 +180,9 @@ class single_level_column_mux(design.design): width=self.bitcell.width, height=self.height) - + def analytical_delay(self, corner, slew, load): + """Returns relative delay that the column mux. Difficult to convert to LE model.""" + parasitic_delay = 1 + cin = 2*self.tx_size #This is not CMOS, so using this may be incorrect. + return logical_effort.logical_effort('column_mux', self.tx_size, cin, load, parasitic_delay, False) diff --git a/compiler/sram_base.py b/compiler/sram_base.py index 611900e4..ad9c2373 100644 --- a/compiler/sram_base.py +++ b/compiler/sram_base.py @@ -11,6 +11,7 @@ from design import design from verilog import verilog from lef import lef from sram_factory import factory +import logical_effort class sram_base(design, verilog, lef): """ @@ -500,10 +501,26 @@ class sram_base(design, verilog, lef): def analytical_delay(self, corner, slew,load): - """ LH and HL are the same in analytical model. """ - return self.bank.analytical_delay(corner,slew,load) + """ Estimates the delay from clk -> DOUT + LH and HL are the same in analytical model. """ + delays = {} + for port in self.all_ports: + if port in self.readonly_ports: + control_logic = self.control_logic_r + elif port in self.readwrite_ports: + control_logic = self.control_logic_rw + else: + continue + clk_to_wlen_delays = control_logic.analytical_delay(corner, slew, load) + wlen_to_dout_delays = self.bank.analytical_delay(corner,slew,load) #port should probably be specified... + all_delays = clk_to_wlen_delays+wlen_to_dout_delays + total_delay = logical_effort.calculate_absolute_delay(all_delays) + last_slew = .1*all_delays[-1].get_absolute_delay() #slew approximated as 10% of delay + delays[port] = self.return_delay(delay=total_delay, slew=last_slew) + + return delays - def determine_wordline_stage_efforts(self, inp_is_rise=True): + def get_wordline_stage_efforts(self, inp_is_rise=True): """Get the all the stage efforts for each stage in the path from clk_buf to a wordline""" stage_effort_list = [] @@ -541,4 +558,12 @@ class sram_base(design, verilog, lef): return self.bank.get_sen_cin() - + def get_dff_clk_buf_cin(self): + """Get the relative capacitance of the clk_buf signal. + Does not get the control logic loading but everything else""" + total_cin = 0 + total_cin += self.row_addr_dff.get_clk_cin() + total_cin += self.data_dff.get_clk_cin() + if self.col_addr_size > 0: + total_cin += self.col_addr_dff.get_clk_cin() + return total_cin \ No newline at end of file diff --git a/compiler/tests/23_lib_sram_model_test.py b/compiler/tests/23_lib_sram_model_test.py index 8a996cb4..d6d4269a 100755 --- a/compiler/tests/23_lib_sram_model_test.py +++ b/compiler/tests/23_lib_sram_model_test.py @@ -15,7 +15,7 @@ class lib_test(openram_test): def runTest(self): globals.init_openram("config_20_{0}".format(OPTS.tech_name)) - + OPTS.netlist_only = True from characterizer import lib from sram import sram from sram_config import sram_config diff --git a/technology/freepdk45/tech/tech.py b/technology/freepdk45/tech/tech.py index 760d2a5a..738bc0ef 100644 --- a/technology/freepdk45/tech/tech.py +++ b/technology/freepdk45/tech/tech.py @@ -336,6 +336,7 @@ spice["nand3_transition_prob"] = .1094 # Transition probability of 3-input na spice["nor2_transition_prob"] = .1875 # Transition probability of 2-input nor. #Parameters related to sense amp enable timing and delay chain/RBL sizing +parameter['le_tau'] = 8 #In pico-seconds. FIXME:This is an assumed value, not measured. parameter["static_delay_stages"] = 4 parameter["static_fanout_per_stage"] = 3 parameter["static_fanout_list"] = parameter["static_delay_stages"]*[parameter["static_fanout_per_stage"]] @@ -344,6 +345,8 @@ parameter["6tcell_wl_cin"] = 3 #relative capacitance parameter["min_inv_para_delay"] = 2.4 #Tau delay units parameter["sa_en_pmos_size"] = .72 #micro-meters parameter["sa_en_nmos_size"] = .27 #micro-meters +parameter["sa_inv_pmos_size"] = .54 #micro-meters +parameter["sa_inv_nmos_size"] = .27 #micro-meters parameter["rbl_height_percentage"] = .5 #Height of RBL compared to bitcell array ################################################### diff --git a/technology/scn4m_subm/tech/tech.py b/technology/scn4m_subm/tech/tech.py index 78222fd6..e127b1a7 100755 --- a/technology/scn4m_subm/tech/tech.py +++ b/technology/scn4m_subm/tech/tech.py @@ -302,6 +302,7 @@ spice["nand3_transition_prob"] = .1094 # Transition probability of 3-input na spice["nor2_transition_prob"] = .1875 # Transition probability of 2-input nor. #Logical Effort relative values for the Handmade cells +parameter['le_tau'] = 40 #In pico-seconds. FIXME:This is an assumed value, not measured. parameter["static_delay_stages"] = 4 parameter["static_fanout_per_stage"] = 3 parameter["static_fanout_list"] = parameter["static_delay_stages"]*[parameter["static_fanout_per_stage"]] @@ -310,6 +311,8 @@ parameter["6tcell_wl_cin"] = 2 parameter["min_inv_para_delay"] = .5 parameter["sa_en_pmos_size"] = 24*_lambda_ parameter["sa_en_nmos_size"] = 9*_lambda_ +parameter["sa_inv_pmos_size"] = 18*_lambda_ +parameter["sa_inv_nmos_size"] = 9*_lambda_ parameter["rbl_height_percentage"] = .5 #Height of RBL compared to bitcell array ################################################### From cc5b347f42c1ddbf0ca8910dcd4f7c8081d76958 Mon Sep 17 00:00:00 2001 From: Hunter Nichols Date: Wed, 3 Apr 2019 16:19:49 -0700 Subject: [PATCH 4/9] Added analyical model test which compares measured delay to model delay. --- compiler/bitcells/bitcell.py | 14 +--- compiler/characterizer/delay.py | 4 +- compiler/characterizer/logical_effort.py | 4 + compiler/modules/bank.py | 48 +++-------- compiler/modules/bitcell_array.py | 22 +---- compiler/modules/sense_amp_array.py | 7 ++ .../modules/single_level_column_mux_array.py | 11 ++- ...y_model_test.py => 21_model_delay_test.py} | 38 ++++++--- compiler/tests/27_worst_case_delay_test.py | 81 ------------------- technology/freepdk45/tech/tech.py | 3 +- technology/scn4m_subm/tech/tech.py | 9 ++- 11 files changed, 71 insertions(+), 170 deletions(-) rename compiler/tests/{28_delay_model_test.py => 21_model_delay_test.py} (57%) delete mode 100755 compiler/tests/27_worst_case_delay_test.py diff --git a/compiler/bitcells/bitcell.py b/compiler/bitcells/bitcell.py index d5712d7f..3f1d02d3 100644 --- a/compiler/bitcells/bitcell.py +++ b/compiler/bitcells/bitcell.py @@ -24,19 +24,7 @@ class bitcell(design.design): self.width = bitcell.width self.height = bitcell.height self.pin_map = bitcell.pin_map - - # def analytical_delay(self, corner, slew, load=0, swing = 0.5): - # # delay of bit cell is not like a driver(from WL) - # # so the slew used should be 0 - # # it should not be slew dependent? - # # because the value is there - # # the delay is only over half transsmission gate - # from tech import spice - # r = spice["min_tx_r"]*3 - # c_para = spice["min_tx_drain_c"] - # result = self.cal_delay_with_rc(corner, r = r, c = c_para+load, slew = slew, swing = swing) - # return result - + def analytical_delay(self, corner, slew, load=0, swing = 0.5): parasitic_delay = 1 size = 0.5 #This accounts for bitline being drained thought the access TX and internal node diff --git a/compiler/characterizer/delay.py b/compiler/characterizer/delay.py index 9c15cd2a..a80fc4dc 100644 --- a/compiler/characterizer/delay.py +++ b/compiler/characterizer/delay.py @@ -9,6 +9,7 @@ import utils from globals import OPTS from .simulation import simulation from .measurements import * +import logical_effort class delay(simulation): """Functions to measure the delay and power of an SRAM at a given address and @@ -904,8 +905,9 @@ class delay(simulation): self.create_measurement_names() power = self.analytical_power(slews, loads) port_data = self.get_empty_measure_data_dict() + relative_loads = [logical_effort.convert_farad_to_relative_c(c_farad) for c_farad in loads] for slew in slews: - for load in loads: + for load in relative_loads: self.set_load_slew(load,slew) bank_delay = self.sram.analytical_delay(self.corner, self.slew,self.load) for port in self.all_ports: diff --git a/compiler/characterizer/logical_effort.py b/compiler/characterizer/logical_effort.py index 97c10d51..860ae68f 100644 --- a/compiler/characterizer/logical_effort.py +++ b/compiler/characterizer/logical_effort.py @@ -67,4 +67,8 @@ def calculate_relative_rise_fall_delays(stage_effort_list): else: total_fall_delay += stage.get_stage_delay() return total_rise_delay, total_fall_delay + +def convert_farad_to_relative_c(c_farad): + """Converts capacitance in Femto-Farads to relative capacitance.""" + return c_farad*parameter['cap_relative_per_ff'] \ No newline at end of file diff --git a/compiler/modules/bank.py b/compiler/modules/bank.py index e6d18e0b..36cfaf97 100644 --- a/compiler/modules/bank.py +++ b/compiler/modules/bank.py @@ -1215,37 +1215,6 @@ class bank(design.design): offset=control_pos, rotate=90) - - # def analytical_delay(self, corner, slew, load): - # """ return analytical delay of the bank""" - # results = [] - - # decoder_delay = self.row_decoder.analytical_delay(corner, slew, self.wordline_driver.input_load()) - - # word_driver_delay = self.wordline_driver.analytical_delay(corner, - # decoder_delay.slew, - # self.bitcell_array.input_load()) - - # #FIXME: Array delay is the same for every port. - # bitcell_array_delay = self.bitcell_array.analytical_delay(corner, word_driver_delay.slew) - - # #This also essentially creates the same delay for each port. Good structure, no substance - # for port in self.all_ports: - # if self.words_per_row > 1: - # column_mux_delay = self.column_mux_array[port].analytical_delay(corner, - # bitcell_array_delay.slew, - # self.sense_amp_array.input_load()) - # else: - # column_mux_delay = self.return_delay(delay = 0.0, slew=word_driver_delay.slew) - - # bl_t_data_out_delay = self.sense_amp_array.analytical_delay(corner, - # column_mux_delay.slew, - # self.bitcell_array.output_load()) - # # output load of bitcell_array is set to be only small part of bl for sense amp. - # results.append(decoder_delay + word_driver_delay + bitcell_array_delay + column_mux_delay + bl_t_data_out_delay) - - # return results - def analytical_delay(self, corner, slew, load): """ return analytical delay of the bank. This will track the clock to output path""" #FIXME: This delay is determined in the control logic. Should be moved here. @@ -1255,20 +1224,27 @@ class bank(design.design): #FIXME: Array delay is the same for every port. word_driver_slew = 0 - bitcell_array_delay = self.bitcell_array.analytical_delay(corner, word_driver_slew) + if self.words_per_row > 1: + bitline_ext_load = self.column_mux_array[port].get_drain_cin() + else: + bitline_ext_load = self.sense_amp_array.get_drain_cin() + + bitcell_array_delay = self.bitcell_array.analytical_delay(corner, word_driver_slew, bitline_ext_load) + bitcell_array_slew = 0 #This also essentially creates the same delay for each port. Good structure, no substance if self.words_per_row > 1: + sa_load = self.sense_amp_array.get_drain_load() column_mux_delay = self.column_mux_array[port].analytical_delay(corner, - bitcell_array_delay.slew, - self.sense_amp_array.input_load()) + bitcell_array_slew, + sa_load) else: column_mux_delay = [] column_mux_slew = 0 sense_amp_delay = self.sense_amp_array.analytical_delay(corner, - column_mux_slew, - self.bitcell_array.output_load()) + column_mux_slew, + load) # output load of bitcell_array is set to be only small part of bl for sense amp. return bitcell_array_delay + column_mux_delay + sense_amp_delay diff --git a/compiler/modules/bitcell_array.py b/compiler/modules/bitcell_array.py index 6aecfd6b..e2e98b5b 100644 --- a/compiler/modules/bitcell_array.py +++ b/compiler/modules/bitcell_array.py @@ -128,27 +128,9 @@ class bitcell_array(design.design): inst = self.cell_inst[row,col] for pin_name in ["vdd", "gnd"]: for pin in inst.get_pins(pin_name): - self.add_power_pin(pin_name, pin.center(), 0, pin.layer) - - - # def analytical_delay(self, corner, slew, load=0): - # from tech import drc - # wl_wire = self.gen_wl_wire() - # wl_wire.return_delay_over_wire(slew) - - # wl_to_cell_delay = wl_wire.return_delay_over_wire(slew) - # # hypothetical delay from cell to bl end without sense amp - # bl_wire = self.gen_bl_wire() - # cell_load = 2 * bl_wire.return_input_cap() # we ingore the wire r - # # hence just use the whole c - # bl_swing = 0.1 - # cell_delay = self.cell.analytical_delay(corner, wl_to_cell_delay.slew, cell_load, swing = bl_swing) - - # #we do not consider the delay over the wire for now - # return self.return_delay(cell_delay.delay+wl_to_cell_delay.delay, - # wl_to_cell_delay.slew) + self.add_power_pin(pin_name, pin.center(), 0, pin.layer) - def analytical_delay(self, corner, slew, load=0): + def analytical_delay(self, corner, slew, load): """Returns relative delay of the bitline in the bitcell array""" #The load being driven/drained is mostly the bitline but could include the sense amp or the column mux. #The load from the bitlines is due to the drain capacitances from all the other bitlines and wire parasitics. diff --git a/compiler/modules/sense_amp_array.py b/compiler/modules/sense_amp_array.py index 83e3d34a..9ba72025 100644 --- a/compiler/modules/sense_amp_array.py +++ b/compiler/modules/sense_amp_array.py @@ -4,6 +4,7 @@ from vector import vector from sram_factory import factory import debug from globals import OPTS +import logical_effort class sense_amp_array(design.design): """ @@ -143,3 +144,9 @@ class sense_amp_array(design.design): """Get the relative capacitance of all the sense amp enable connections in the array""" sense_amp_en_cin = self.amp.get_en_cin() return sense_amp_en_cin * self.word_size + + def get_drain_cin(self): + """Get the relative capacitance of the drain of the PMOS isolation TX""" + #Estimated as half a parasitic delay. + drain_parasitics = .5 + return drain_parasitics * logical_effort.logical_effort.pinv diff --git a/compiler/modules/single_level_column_mux_array.py b/compiler/modules/single_level_column_mux_array.py index c2414653..3247592e 100644 --- a/compiler/modules/single_level_column_mux_array.py +++ b/compiler/modules/single_level_column_mux_array.py @@ -7,6 +7,7 @@ import math from vector import vector from sram_factory import factory from globals import OPTS +import logical_effort class single_level_column_mux_array(design.design): """ @@ -232,5 +233,11 @@ class single_level_column_mux_array(design.design): """Returns relative delay that the column mux adds""" #Single level column mux will add parasitic loads from other mux pass transistors and the sense amp. drain_parasitics = .5 #Assumed parasitics from unused TXs - array_load = drain_parasitics*self.words_per_row*logical_effort.pinv - return [self.mux.analytical_delay(corner, slew, load+array_load)] \ No newline at end of file + array_load = drain_parasitics*self.words_per_row*logical_effort.logical_effort.pinv + return [self.mux.analytical_delay(corner, slew, load+array_load)] + + def get_drain_cin(self): + """Get the relative capacitance of the drain of the NMOS pass TX""" + #Estimated as half a parasitic delay. + drain_parasitics = .5 + return drain_parasitics * logical_effort.logical_effort.pinv \ No newline at end of file diff --git a/compiler/tests/28_delay_model_test.py b/compiler/tests/21_model_delay_test.py similarity index 57% rename from compiler/tests/28_delay_model_test.py rename to compiler/tests/21_model_delay_test.py index a02a42e9..7e9c00e4 100755 --- a/compiler/tests/28_delay_model_test.py +++ b/compiler/tests/21_model_delay_test.py @@ -11,25 +11,22 @@ import globals from globals import OPTS import debug -class delay_model_test(openram_test): +class model_delay_sram_test(openram_test): def runTest(self): globals.init_openram("config_20_{0}".format(OPTS.tech_name)) - OPTS.spice_name="hspice" + #OPTS.spice_name="hspice" OPTS.analytical_delay = False OPTS.netlist_only = True - OPTS.trim_netlist = False - debug.info(1, "Trimming disabled for this test. Simulation could be slow.") # This is a hack to reload the characterizer __init__ with the spice version from importlib import reload import characterizer reload(characterizer) - - from characterizer import model_check + from characterizer import delay from sram import sram from sram_config import sram_config - c = sram_config(word_size=4, + c = sram_config(word_size=1, num_words=16, num_banks=1) c.words_per_row=1 @@ -45,15 +42,32 @@ class delay_model_test(openram_test): debug.info(1, "Probe address {0} probe data bit {1}".format(probe_address, probe_data)) corner = (OPTS.process_corners[0], OPTS.supply_voltages[0], OPTS.temperatures[0]) - mc = model_check(s.s, tempspice, corner) + d = delay(s.s, tempspice, corner) import tech loads = [tech.spice["msflop_in_cap"]*4] slews = [tech.spice["rise_time"]*2] - sram_data = mc.analyze(probe_address, probe_data, slews, loads) - #Combine info about port into all data - - #debug.info(1,"Data:\n{}".format(wl_data)) + spice_data, port_data = d.analyze(probe_address, probe_data, slews, loads) + spice_data.update(port_data[0]) + + model_data, port_data = d.analytical_delay(slews, loads) + model_data.update(port_data[0]) + + #Only compare the delays + spice_delays = {key:value for key, value in spice_data.items() if 'delay' in key} + model_delays = {key:value for key, value in model_data.items() if 'delay' in key} + debug.info(1,"Spice Delays={}".format(spice_delays)) + debug.info(1,"Model Delays={}".format(model_delays)) + if OPTS.tech_name == "freepdk45": + error_tolerance = .25 + elif OPTS.tech_name == "scn4m_subm": + error_tolerance = .25 + else: + self.assertTrue(False) # other techs fail + # Check if no too many or too few results + self.assertTrue(len(spice_delays.keys())==len(model_delays.keys())) + self.assertTrue(self.check_golden_data(spice_delays,model_delays,error_tolerance)) + globals.end_openram() # run the test from the command line diff --git a/compiler/tests/27_worst_case_delay_test.py b/compiler/tests/27_worst_case_delay_test.py deleted file mode 100755 index 834c6b69..00000000 --- a/compiler/tests/27_worst_case_delay_test.py +++ /dev/null @@ -1,81 +0,0 @@ -#!/usr/bin/env python3 -""" -Run a regression test on various srams -""" - -import unittest -from testutils import header,openram_test -import sys,os -sys.path.append(os.path.join(sys.path[0],"..")) -import globals -from globals import OPTS -import debug - -@unittest.skip("SKIPPING 27_worst_case_delay_test") -class worst_case_timing_sram_test(openram_test): - - def runTest(self): - OPTS.tech_name = "freepdk45" - globals.init_openram("config_20_{0}".format(OPTS.tech_name)) - OPTS.spice_name="hspice" - OPTS.analytical_delay = False - OPTS.netlist_only = True - OPTS.trim_netlist = False - OPTS.check_lvsdrc = True - - - # This is a hack to reload the characterizer __init__ with the spice version - from importlib import reload - import characterizer - reload(characterizer) - from characterizer import worst_case - if not OPTS.spice_exe: - debug.error("Could not find {} simulator.".format(OPTS.spice_name),-1) - - word_size, num_words, num_banks = 2, 16, 1 - from sram import sram - from sram_config import sram_config - c = sram_config(word_size=word_size, - num_words=num_words, - num_banks=num_banks) - c.words_per_row=1 - c.recompute_sizes() - debug.info(1, "Testing the timing different bitecells inside a {}bit, {} words SRAM with {} bank".format( - word_size, num_words, num_banks)) - s = sram(c, name="sram1") - - sp_netlist_file = OPTS.openram_temp + "temp.sp" - s.sp_write(sp_netlist_file) - - if OPTS.use_pex: - gdsname = OPTS.output_path + s.name + ".gds" - s.gds_write(gdsname) - - import verify - reload(verify) - # Output the extracted design if requested - sp_pex_file = OPTS.output_path + s.name + "_pex.sp" - verify.run_pex(s.name, gdsname, sp_netlist_file, output=sp_pex_file) - sp_sim_file = sp_pex_file - debug.info(1, "Performing spice simulations with backannotated spice file.") - else: - sp_sim_file = sp_netlist_file - debug.info(1, "Performing spice simulations with spice netlist.") - - corner = (OPTS.process_corners[0], OPTS.supply_voltages[0], OPTS.temperatures[0]) - wc = worst_case(s.s, sp_sim_file, corner) - import tech - loads = [tech.spice["msflop_in_cap"]*4] - slews = [tech.spice["rise_time"]*2] - probe_address = "1" * s.s.addr_size - probe_data = s.s.word_size - 1 - wc.analyze(probe_address, probe_data, slews, loads) - - globals.end_openram() - -# run the test from the command line -if __name__ == "__main__": - (OPTS, args) = globals.parse_args() - del sys.argv[1:] - header(__file__, OPTS.tech_name) - unittest.main() diff --git a/technology/freepdk45/tech/tech.py b/technology/freepdk45/tech/tech.py index 738bc0ef..93f55637 100644 --- a/technology/freepdk45/tech/tech.py +++ b/technology/freepdk45/tech/tech.py @@ -336,7 +336,8 @@ spice["nand3_transition_prob"] = .1094 # Transition probability of 3-input na spice["nor2_transition_prob"] = .1875 # Transition probability of 2-input nor. #Parameters related to sense amp enable timing and delay chain/RBL sizing -parameter['le_tau'] = 8 #In pico-seconds. FIXME:This is an assumed value, not measured. +parameter['le_tau'] = 2.25 #In pico-seconds. +parameter['cap_relative_per_ff'] = 7.5 #Units of Relative Capacitance/ Femto-Farad parameter["static_delay_stages"] = 4 parameter["static_fanout_per_stage"] = 3 parameter["static_fanout_list"] = parameter["static_delay_stages"]*[parameter["static_fanout_per_stage"]] diff --git a/technology/scn4m_subm/tech/tech.py b/technology/scn4m_subm/tech/tech.py index e127b1a7..53a3a255 100755 --- a/technology/scn4m_subm/tech/tech.py +++ b/technology/scn4m_subm/tech/tech.py @@ -302,13 +302,14 @@ spice["nand3_transition_prob"] = .1094 # Transition probability of 3-input na spice["nor2_transition_prob"] = .1875 # Transition probability of 2-input nor. #Logical Effort relative values for the Handmade cells -parameter['le_tau'] = 40 #In pico-seconds. FIXME:This is an assumed value, not measured. +parameter['le_tau'] = 23 #In pico-seconds. +parameter["min_inv_para_delay"] = .73 #In relative delay units +parameter['cap_relative_per_ff'] = .91 #Units of Relative Capacitance/ Femto-Farad parameter["static_delay_stages"] = 4 parameter["static_fanout_per_stage"] = 3 parameter["static_fanout_list"] = parameter["static_delay_stages"]*[parameter["static_fanout_per_stage"]] -parameter["dff_clk_cin"] = 27.5 -parameter["6tcell_wl_cin"] = 2 -parameter["min_inv_para_delay"] = .5 +parameter["dff_clk_cin"] = 27.5 #In relative capacitance units +parameter["6tcell_wl_cin"] = 2 #In relative capacitance units parameter["sa_en_pmos_size"] = 24*_lambda_ parameter["sa_en_nmos_size"] = 9*_lambda_ parameter["sa_inv_pmos_size"] = 18*_lambda_ From 14385194950e201faa2561146342b6eda392615a Mon Sep 17 00:00:00 2001 From: Hunter Nichols Date: Wed, 3 Apr 2019 17:53:28 -0700 Subject: [PATCH 5/9] Added check to pdriver for 0 fanout which can break compute_sizes. --- compiler/pgates/pdriver.py | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/compiler/pgates/pdriver.py b/compiler/pgates/pdriver.py index 5b4a6c9a..02e4355c 100644 --- a/compiler/pgates/pdriver.py +++ b/compiler/pgates/pdriver.py @@ -11,7 +11,7 @@ class pdriver(pgate.pgate): """ This instantiates an even or odd number of inverters sized for driving a load. """ - def __init__(self, name, neg_polarity=False, fanout=1, size_list=None, height=None): + def __init__(self, name, neg_polarity=False, fanout=0, size_list=None, height=None): self.stage_effort = 3 self.height = height @@ -19,6 +19,8 @@ class pdriver(pgate.pgate): self.size_list = size_list self.fanout = fanout + if size_list == None and self.fanout == 0: + debug.error("Either fanout or size list must be specified.", -1) if self.size_list and self.fanout != 0: debug.error("Cannot specify both size_list and fanout.", -1) if self.size_list and self.neg_polarity: From 25c034f85de57ee9aabec5be1bfe1b7a81813b10 Mon Sep 17 00:00:00 2001 From: Hunter Nichols Date: Tue, 9 Apr 2019 01:56:32 -0700 Subject: [PATCH 6/9] Added more accurate bitline delay capacitance estimations --- compiler/modules/bank.py | 3 ++- compiler/modules/bitcell_array.py | 7 ++--- compiler/modules/sense_amp_array.py | 7 ++--- .../modules/single_level_column_mux_array.py | 26 ++++++------------- compiler/pgates/single_level_column_mux.py | 1 + technology/freepdk45/tech/tech.py | 1 + technology/scn4m_subm/tech/tech.py | 1 + 7 files changed, 21 insertions(+), 25 deletions(-) diff --git a/compiler/modules/bank.py b/compiler/modules/bank.py index 36cfaf97..5df8ee87 100644 --- a/compiler/modules/bank.py +++ b/compiler/modules/bank.py @@ -1224,6 +1224,7 @@ class bank(design.design): #FIXME: Array delay is the same for every port. word_driver_slew = 0 + port = 0 if self.words_per_row > 1: bitline_ext_load = self.column_mux_array[port].get_drain_cin() else: @@ -1234,7 +1235,7 @@ class bank(design.design): bitcell_array_slew = 0 #This also essentially creates the same delay for each port. Good structure, no substance if self.words_per_row > 1: - sa_load = self.sense_amp_array.get_drain_load() + sa_load = self.sense_amp_array.get_drain_cin() column_mux_delay = self.column_mux_array[port].analytical_delay(corner, bitcell_array_slew, sa_load) diff --git a/compiler/modules/bitcell_array.py b/compiler/modules/bitcell_array.py index e2e98b5b..79c68241 100644 --- a/compiler/modules/bitcell_array.py +++ b/compiler/modules/bitcell_array.py @@ -132,11 +132,12 @@ class bitcell_array(design.design): def analytical_delay(self, corner, slew, load): """Returns relative delay of the bitline in the bitcell array""" + from tech import parameter #The load being driven/drained is mostly the bitline but could include the sense amp or the column mux. #The load from the bitlines is due to the drain capacitances from all the other bitlines and wire parasitics. - drain_parasitics = .5 #each bitcell adds half a parasitic to the delay - wire_parasitics = .05 * drain_parasitics #Wires add 5% to this. - bitline_load = (drain_parasitics+wire_parasitics)*self.row_size * logical_effort.logical_effort.pinv + drain_load = logical_effort.convert_farad_to_relative_c(parameter['bitcell_drain_cap']) + wire_unit_load = .05 * drain_load #Wires add 5% to this. + bitline_load = (drain_load+wire_unit_load)*self.row_size return [self.cell.analytical_delay(corner, slew, load+bitline_load)] def analytical_power(self, corner, load): diff --git a/compiler/modules/sense_amp_array.py b/compiler/modules/sense_amp_array.py index 9ba72025..c9722e50 100644 --- a/compiler/modules/sense_amp_array.py +++ b/compiler/modules/sense_amp_array.py @@ -147,6 +147,7 @@ class sense_amp_array(design.design): def get_drain_cin(self): """Get the relative capacitance of the drain of the PMOS isolation TX""" - #Estimated as half a parasitic delay. - drain_parasitics = .5 - return drain_parasitics * logical_effort.logical_effort.pinv + from tech import parameter + #Bitcell drain load being used to estimate PMOS drain load + drain_load = logical_effort.convert_farad_to_relative_c(parameter['bitcell_drain_cap']) + return drain_load diff --git a/compiler/modules/single_level_column_mux_array.py b/compiler/modules/single_level_column_mux_array.py index 3247592e..d7829900 100644 --- a/compiler/modules/single_level_column_mux_array.py +++ b/compiler/modules/single_level_column_mux_array.py @@ -216,28 +216,18 @@ class single_level_column_mux_array(design.design): self.add_via(layers=("metal1", "via1", "metal2"), offset= br_out_offset, rotate=90) - - def analytical_delay(self, corner, vdd, slew, load=0.0): - from tech import spice, parameter - proc,vdd,temp = corner - r = spice["min_tx_r"]/(self.mux.ptx_width/parameter["min_tx_size"]) - #Drains of mux transistors make up capacitance. - c_para = spice["min_tx_drain_c"]*(self.mux.ptx_width/parameter["min_tx_size"])*self.words_per_row#ff - volt_swing = spice["v_threshold_typical"]/vdd - - result = self.cal_delay_with_rc(corner, r = r, c = c_para+load, slew = slew, swing = volt_swing) - return self.return_delay(result.delay, result.slew) - - + def analytical_delay(self, corner, slew, load): + from tech import parameter """Returns relative delay that the column mux adds""" #Single level column mux will add parasitic loads from other mux pass transistors and the sense amp. - drain_parasitics = .5 #Assumed parasitics from unused TXs - array_load = drain_parasitics*self.words_per_row*logical_effort.logical_effort.pinv + drain_load = logical_effort.convert_farad_to_relative_c(parameter['bitcell_drain_cap']) + array_load = drain_load*self.words_per_row return [self.mux.analytical_delay(corner, slew, load+array_load)] def get_drain_cin(self): """Get the relative capacitance of the drain of the NMOS pass TX""" - #Estimated as half a parasitic delay. - drain_parasitics = .5 - return drain_parasitics * logical_effort.logical_effort.pinv \ No newline at end of file + from tech import parameter + #Bitcell drain load being used to estimate mux NMOS drain load + drain_load = logical_effort.convert_farad_to_relative_c(parameter['bitcell_drain_cap']) + return drain_load \ No newline at end of file diff --git a/compiler/pgates/single_level_column_mux.py b/compiler/pgates/single_level_column_mux.py index d4ff9561..2bdf5bef 100644 --- a/compiler/pgates/single_level_column_mux.py +++ b/compiler/pgates/single_level_column_mux.py @@ -5,6 +5,7 @@ from vector import vector import contact from globals import OPTS from sram_factory import factory +import logical_effort class single_level_column_mux(design.design): """ diff --git a/technology/freepdk45/tech/tech.py b/technology/freepdk45/tech/tech.py index 93f55637..1bf1c0e7 100644 --- a/technology/freepdk45/tech/tech.py +++ b/technology/freepdk45/tech/tech.py @@ -349,6 +349,7 @@ parameter["sa_en_nmos_size"] = .27 #micro-meters parameter["sa_inv_pmos_size"] = .54 #micro-meters parameter["sa_inv_nmos_size"] = .27 #micro-meters parameter["rbl_height_percentage"] = .5 #Height of RBL compared to bitcell array +parameter['bitcell_drain_cap'] = 0.1 #In Femto-Farad, approximation of drain capacitance ################################################### ##END Spice Simulation Parameters diff --git a/technology/scn4m_subm/tech/tech.py b/technology/scn4m_subm/tech/tech.py index 53a3a255..23901b0d 100755 --- a/technology/scn4m_subm/tech/tech.py +++ b/technology/scn4m_subm/tech/tech.py @@ -315,6 +315,7 @@ parameter["sa_en_nmos_size"] = 9*_lambda_ parameter["sa_inv_pmos_size"] = 18*_lambda_ parameter["sa_inv_nmos_size"] = 9*_lambda_ parameter["rbl_height_percentage"] = .5 #Height of RBL compared to bitcell array +parameter['bitcell_drain_cap'] = 0.2 #In Femto-Farad, approximation of drain capacitance ################################################### ##END Spice Simulation Parameters From a500d7ee3dffcf53efba6eaec7637cc82880492b Mon Sep 17 00:00:00 2001 From: Hunter Nichols Date: Tue, 9 Apr 2019 02:49:52 -0700 Subject: [PATCH 7/9] Adjusted bitcell analytical delays for multiport cells. --- compiler/bitcells/bitcell_1rw_1r.py | 17 ++++++----------- compiler/bitcells/bitcell_1w_1r.py | 17 ++++++----------- compiler/bitcells/pbitcell.py | 17 +++++++++++------ compiler/modules/bank.py | 3 +-- compiler/sram_base.py | 2 +- 5 files changed, 25 insertions(+), 31 deletions(-) diff --git a/compiler/bitcells/bitcell_1rw_1r.py b/compiler/bitcells/bitcell_1rw_1r.py index a96dcff0..e597167f 100644 --- a/compiler/bitcells/bitcell_1rw_1r.py +++ b/compiler/bitcells/bitcell_1rw_1r.py @@ -2,6 +2,7 @@ import design import debug import utils from tech import GDS,layer,parameter,drc +import logical_effort class bitcell_1rw_1r(design.design): """ @@ -25,18 +26,12 @@ class bitcell_1rw_1r(design.design): self.pin_map = bitcell_1rw_1r.pin_map def analytical_delay(self, corner, slew, load=0, swing = 0.5): - # delay of bit cell is not like a driver(from WL) - # so the slew used should be 0 - # it should not be slew dependent? - # because the value is there - # the delay is only over half transsmission gate - from tech import spice - r = spice["min_tx_r"]*3 - c_para = spice["min_tx_drain_c"] - result = self.cal_delay_with_rc(corner, r = r, c = c_para+load, slew = slew, swing = swing) - return result + parasitic_delay = 1 + size = 0.5 #This accounts for bitline being drained thought the access TX and internal node + cin = 3 #Assumes always a minimum sizes inverter. Could be specified in the tech.py file. + read_port_load = 0.5 #min size NMOS gate load + return logical_effort.logical_effort('bitline', size, cin, load+read_port_load, parasitic_delay, False) - def list_bitcell_pins(self, col, row): """ Creates a list of connections in the bitcell, indexed by column and row, for instance use in bitcell_array """ bitcell_pins = ["bl0_{0}".format(col), diff --git a/compiler/bitcells/bitcell_1w_1r.py b/compiler/bitcells/bitcell_1w_1r.py index e2cc662b..cf487fba 100644 --- a/compiler/bitcells/bitcell_1w_1r.py +++ b/compiler/bitcells/bitcell_1w_1r.py @@ -2,6 +2,7 @@ import design import debug import utils from tech import GDS,layer,parameter,drc +import logical_effort class bitcell_1w_1r(design.design): """ @@ -25,18 +26,12 @@ class bitcell_1w_1r(design.design): self.pin_map = bitcell_1w_1r.pin_map def analytical_delay(self, corner, slew, load=0, swing = 0.5): - # delay of bit cell is not like a driver(from WL) - # so the slew used should be 0 - # it should not be slew dependent? - # because the value is there - # the delay is only over half transsmission gate - from tech import spice - r = spice["min_tx_r"]*3 - c_para = spice["min_tx_drain_c"] - result = self.cal_delay_with_rc(corner, r = r, c = c_para+load, slew = slew, swing = swing) - return result + parasitic_delay = 1 + size = 0.5 #This accounts for bitline being drained thought the access TX and internal node + cin = 3 #Assumes always a minimum sizes inverter. Could be specified in the tech.py file. + read_port_load = 0.5 #min size NMOS gate load + return logical_effort.logical_effort('bitline', size, cin, load+read_port_load, parasitic_delay, False) - def list_bitcell_pins(self, col, row): """ Creates a list of connections in the bitcell, indexed by column and row, for instance use in bitcell_array """ bitcell_pins = ["bl0_{0}".format(col), diff --git a/compiler/bitcells/pbitcell.py b/compiler/bitcells/pbitcell.py index 55712e44..94c294db 100644 --- a/compiler/bitcells/pbitcell.py +++ b/compiler/bitcells/pbitcell.py @@ -5,6 +5,7 @@ from tech import drc, parameter, spice from vector import vector from ptx import ptx from globals import OPTS +import logical_effort class pbitcell(design.design): """ @@ -867,12 +868,16 @@ class pbitcell(design.design): self.add_path("metal1", [Q_bar_pos, vdd_pos]) def analytical_delay(self, corner, slew, load=0, swing = 0.5): - #FIXME: Delay copied exactly over from bitcell - from tech import spice - r = spice["min_tx_r"]*3 - c_para = spice["min_tx_drain_c"] - result = self.cal_delay_with_rc(corner, r = r, c = c_para+load, slew = slew, swing = swing) - return result + parasitic_delay = 1 + size = 0.5 #This accounts for bitline being drained thought the access TX and internal node + cin = 3 #Assumes always a minimum sizes inverter. Could be specified in the tech.py file. + + #Internal loads due to port configs are halved. This is to account for the size already being halved + #for stacked TXs, but internal loads do not see this size estimation. + write_port_load = self.num_w_ports*logical_effort.convert_farad_to_relative_c(parameter['bitcell_drain_cap'])/2 + read_port_load = self.num_r_ports/2 #min size NMOS gate load + total_load = load+read_port_load+write_port_load + return logical_effort.logical_effort('bitline', size, cin, load+read_port_load, parasitic_delay, False) def analytical_power(self, corner, load): """Bitcell power in nW. Only characterizes leakage.""" diff --git a/compiler/modules/bank.py b/compiler/modules/bank.py index 5df8ee87..5b556660 100644 --- a/compiler/modules/bank.py +++ b/compiler/modules/bank.py @@ -1215,7 +1215,7 @@ class bank(design.design): offset=control_pos, rotate=90) - def analytical_delay(self, corner, slew, load): + def analytical_delay(self, corner, slew, load, port): """ return analytical delay of the bank. This will track the clock to output path""" #FIXME: This delay is determined in the control logic. Should be moved here. # word_driver_delay = self.wordline_driver.analytical_delay(corner, @@ -1224,7 +1224,6 @@ class bank(design.design): #FIXME: Array delay is the same for every port. word_driver_slew = 0 - port = 0 if self.words_per_row > 1: bitline_ext_load = self.column_mux_array[port].get_drain_cin() else: diff --git a/compiler/sram_base.py b/compiler/sram_base.py index a7f0e965..6d859358 100644 --- a/compiler/sram_base.py +++ b/compiler/sram_base.py @@ -517,7 +517,7 @@ class sram_base(design, verilog, lef): else: continue clk_to_wlen_delays = control_logic.analytical_delay(corner, slew, load) - wlen_to_dout_delays = self.bank.analytical_delay(corner,slew,load) #port should probably be specified... + wlen_to_dout_delays = self.bank.analytical_delay(corner,slew,load,port) #port should probably be specified... all_delays = clk_to_wlen_delays+wlen_to_dout_delays total_delay = logical_effort.calculate_absolute_delay(all_delays) last_slew = .1*all_delays[-1].get_absolute_delay() #slew approximated as 10% of delay From c1411f422776bd5ea3de2b2cbb73898fa665a858 Mon Sep 17 00:00:00 2001 From: Hunter Nichols Date: Tue, 9 Apr 2019 12:26:54 -0700 Subject: [PATCH 8/9] Applied quick corner estimation to analytical delay. --- compiler/base/hierarchy_spice.py | 16 ++++++++++------ compiler/sram_base.py | 2 ++ 2 files changed, 12 insertions(+), 6 deletions(-) diff --git a/compiler/base/hierarchy_spice.py b/compiler/base/hierarchy_spice.py index 5f3245a8..cb2799f3 100644 --- a/compiler/base/hierarchy_spice.py +++ b/compiler/base/hierarchy_spice.py @@ -235,13 +235,8 @@ class spice(): modeling it as a resistance driving a capacitance """ swing_factor = abs(math.log(1-swing)) # time constant based on swing - proc,vdd,temp = corner - #FIXME: type of delay is needed to know which process to use. - proc_mult = max(self.get_process_delay_factor(proc)) - volt_mult = self.get_voltage_delay_factor(vdd) - temp_mult = self.get_temp_delay_factor(temp) delay = swing_factor * r * c #c is in ff and delay is in fs - delay = delay * proc_mult * volt_mult * temp_mult + delay = self.apply_corners_analytically(delay, corner) delay = delay * 0.001 #make the unit to ps # Output slew should be linear to input slew which is described @@ -254,6 +249,15 @@ class spice(): slew = delay * 0.6 * 2 + 0.005 * slew return delay_data(delay = delay, slew = slew) + def apply_corners_analytically(self, delay, corner): + """Multiply delay by corner factors""" + proc,vdd,temp = corner + #FIXME: type of delay is needed to know which process to use. + proc_mult = max(self.get_process_delay_factor(proc)) + volt_mult = self.get_voltage_delay_factor(vdd) + temp_mult = self.get_temp_delay_factor(temp) + return delay * proc_mult * volt_mult * temp_mult + def get_process_delay_factor(self, proc): """Returns delay increase estimate based off process Currently does +/-10 for fast/slow corners.""" diff --git a/compiler/sram_base.py b/compiler/sram_base.py index 6d859358..177f34c6 100644 --- a/compiler/sram_base.py +++ b/compiler/sram_base.py @@ -520,7 +520,9 @@ class sram_base(design, verilog, lef): wlen_to_dout_delays = self.bank.analytical_delay(corner,slew,load,port) #port should probably be specified... all_delays = clk_to_wlen_delays+wlen_to_dout_delays total_delay = logical_effort.calculate_absolute_delay(all_delays) + total_delay = self.apply_corners_analytically(total_delay, corner) last_slew = .1*all_delays[-1].get_absolute_delay() #slew approximated as 10% of delay + last_slew = self.apply_corners_analytically(last_slew, corner) delays[port] = self.return_delay(delay=total_delay, slew=last_slew) return delays From 77423ac0693c64d2e1b18b9f23a5d28a4455b56e Mon Sep 17 00:00:00 2001 From: Matt Guthaus Date: Wed, 17 Apr 2019 14:25:39 -0700 Subject: [PATCH 9/9] Remove private token from badges. --- README.md | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/README.md b/README.md index ad21c63c..805d870b 100644 --- a/README.md +++ b/README.md @@ -4,13 +4,13 @@ [![License: BSD 3-clause](./images/license_badge.svg)](./LICENSE) Master: -[![Pipeline Status](https://scone.soe.ucsc.edu:8888/mrg/PrivateRAM/badges/master/pipeline.svg?private_token=ynB6rSFLzvKUseoBPcwV)](https://github.com/VLSIDA/PrivateRAM/commits/master) -![Coverage](https://scone.soe.ucsc.edu:8888/mrg/PrivateRAM/badges/master/coverage.svg?private_token=ynB6rSFLzvKUseoBPcwV) +[![Pipeline Status](https://scone.soe.ucsc.edu:8888/mrg/PrivateRAM/badges/master/pipeline.svg)](https://github.com/VLSIDA/PrivateRAM/commits/master) +![Coverage](https://scone.soe.ucsc.edu:8888/mrg/PrivateRAM/badges/master/coverage.svg) [![Download](./images/download-stable-blue.svg)](https://github.com/VLSIDA/PrivateRAM/archive/master.zip) Dev: -[![Pipeline Status](https://scone.soe.ucsc.edu:8888/mrg/PrivateRAM/badges/dev/pipeline.svg?private_token=ynB6rSFLzvKUseoBPcwV)](https://github.com/VLSIDA/PrivateRAM/commits/dev) -![Coverage](https://scone.soe.ucsc.edu:8888/mrg/PrivateRAM/badges/dev/coverage.svg?private_token=ynB6rSFLzvKUseoBPcwV) +[![Pipeline Status](https://scone.soe.ucsc.edu:8888/mrg/PrivateRAM/badges/dev/pipeline.svg)](https://github.com/VLSIDA/PrivateRAM/commits/dev) +![Coverage](https://scone.soe.ucsc.edu:8888/mrg/PrivateRAM/badges/dev/coverage.svg) [![Download](./images/download-unstable-blue.svg)](https://github.com/VLSIDA/PrivateRAM/archive/dev.zip) An open-source static random access memory (SRAM) compiler.