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Diffstat (limited to 'ext/mcpat/cacti/wire.cc')
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diff --git a/ext/mcpat/cacti/wire.cc b/ext/mcpat/cacti/wire.cc new file mode 100644 index 000000000..742000c85 --- /dev/null +++ b/ext/mcpat/cacti/wire.cc @@ -0,0 +1,832 @@ +/***************************************************************************** + * McPAT/CACTI + * SOFTWARE LICENSE AGREEMENT + * Copyright 2012 Hewlett-Packard Development Company, L.P. + * All Rights Reserved + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.” + * + ***************************************************************************/ + +#include "wire.h" +#include "cmath" +// use this constructor to calculate wire stats +Wire::Wire( + enum Wire_type wire_model, + double wl, + int n, + double w_s, + double s_s, + enum Wire_placement wp, + double resistivity, + TechnologyParameter::DeviceType *dt + ):wt(wire_model), wire_length(wl*1e-6), nsense(n), w_scale(w_s), s_scale(s_s), + resistivity(resistivity), deviceType(dt) +{ + wire_placement = wp; + min_w_pmos = deviceType->n_to_p_eff_curr_drv_ratio*g_tp.min_w_nmos_; + in_rise_time = 0; + out_rise_time = 0; + if (initialized != 1) { + cout << "Wire not initialized. Initializing it with default values\n"; + Wire winit; + } + calculate_wire_stats(); + // change everything back to seconds, microns, and Joules + repeater_spacing *= 1e6; + wire_length *= 1e6; + wire_width *= 1e6; + wire_spacing *= 1e6; + assert(wire_length > 0); + assert(power.readOp.dynamic > 0); + assert(power.readOp.leakage > 0); + assert(power.readOp.gate_leakage > 0); +} + + // the following values are for peripheral global technology + // specified in the input config file + Component Wire::global; + Component Wire::global_5; + Component Wire::global_10; + Component Wire::global_20; + Component Wire::global_30; + Component Wire::low_swing; + + int Wire::initialized; + double Wire::wire_width_init; + double Wire::wire_spacing_init; + + +Wire::Wire(double w_s, double s_s, enum Wire_placement wp, double resis, TechnologyParameter::DeviceType *dt) +{ + w_scale = w_s; + s_scale = s_s; + deviceType = dt; + wire_placement = wp; + resistivity = resis; + min_w_pmos = deviceType->n_to_p_eff_curr_drv_ratio * g_tp.min_w_nmos_; + in_rise_time = 0; + out_rise_time = 0; + + switch (wire_placement) + { + case outside_mat: wire_width = g_tp.wire_outside_mat.pitch; break; + case inside_mat : wire_width = g_tp.wire_inside_mat.pitch; break; + default: wire_width = g_tp.wire_local.pitch; break; + } + + wire_spacing = wire_width; + + wire_width *= (w_scale * 1e-6/2) /* (m) */; + wire_spacing *= (s_scale * 1e-6/2) /* (m) */; + + initialized = 1; + init_wire(); + wire_width_init = wire_width; + wire_spacing_init = wire_spacing; + + assert(power.readOp.dynamic > 0); + assert(power.readOp.leakage > 0); + assert(power.readOp.gate_leakage > 0); +} + + + +Wire::~Wire() +{ +} + + + +void +Wire::calculate_wire_stats() +{ + + if (wire_placement == outside_mat) { + wire_width = g_tp.wire_outside_mat.pitch; + } + else if (wire_placement == inside_mat) { + wire_width = g_tp.wire_inside_mat.pitch; + } + else { + wire_width = g_tp.wire_local.pitch; + } + + wire_spacing = wire_width; + + wire_width *= (w_scale * 1e-6/2) /* (m) */; + wire_spacing *= (s_scale * 1e-6/2) /* (m) */; + + + if (wt != Low_swing) { + + // delay_optimal_wire(); + + if (wt == Global) { + delay = global.delay * wire_length; + power.readOp.dynamic = global.power.readOp.dynamic * wire_length; + power.readOp.leakage = global.power.readOp.leakage * wire_length; + power.readOp.gate_leakage = global.power.readOp.gate_leakage * wire_length; + repeater_spacing = global.area.w; + repeater_size = global.area.h; + area.set_area((wire_length/repeater_spacing) * + compute_gate_area(INV, 1, min_w_pmos * repeater_size, + g_tp.min_w_nmos_ * repeater_size, g_tp.cell_h_def)); + } + else if (wt == Global_5) { + delay = global_5.delay * wire_length; + power.readOp.dynamic = global_5.power.readOp.dynamic * wire_length; + power.readOp.leakage = global_5.power.readOp.leakage * wire_length; + power.readOp.gate_leakage = global_5.power.readOp.gate_leakage * wire_length; + repeater_spacing = global_5.area.w; + repeater_size = global_5.area.h; + area.set_area((wire_length/repeater_spacing) * + compute_gate_area(INV, 1, min_w_pmos * repeater_size, + g_tp.min_w_nmos_ * repeater_size, g_tp.cell_h_def)); + } + else if (wt == Global_10) { + delay = global_10.delay * wire_length; + power.readOp.dynamic = global_10.power.readOp.dynamic * wire_length; + power.readOp.leakage = global_10.power.readOp.leakage * wire_length; + power.readOp.gate_leakage = global_10.power.readOp.gate_leakage * wire_length; + repeater_spacing = global_10.area.w; + repeater_size = global_10.area.h; + area.set_area((wire_length/repeater_spacing) * + compute_gate_area(INV, 1, min_w_pmos * repeater_size, + g_tp.min_w_nmos_ * repeater_size, g_tp.cell_h_def)); + } + else if (wt == Global_20) { + delay = global_20.delay * wire_length; + power.readOp.dynamic = global_20.power.readOp.dynamic * wire_length; + power.readOp.leakage = global_20.power.readOp.leakage * wire_length; + power.readOp.gate_leakage = global_20.power.readOp.gate_leakage * wire_length; + repeater_spacing = global_20.area.w; + repeater_size = global_20.area.h; + area.set_area((wire_length/repeater_spacing) * + compute_gate_area(INV, 1, min_w_pmos * repeater_size, + g_tp.min_w_nmos_ * repeater_size, g_tp.cell_h_def)); + } + else if (wt == Global_30) { + delay = global_30.delay * wire_length; + power.readOp.dynamic = global_30.power.readOp.dynamic * wire_length; + power.readOp.leakage = global_30.power.readOp.leakage * wire_length; + power.readOp.gate_leakage = global_30.power.readOp.gate_leakage * wire_length; + repeater_spacing = global_30.area.w; + repeater_size = global_30.area.h; + area.set_area((wire_length/repeater_spacing) * + compute_gate_area(INV, 1, min_w_pmos * repeater_size, + g_tp.min_w_nmos_ * repeater_size, g_tp.cell_h_def)); + } + out_rise_time = delay*repeater_spacing/deviceType->Vth; + } + else if (wt == Low_swing) { + low_swing_model (); + repeater_spacing = wire_length; + repeater_size = 1; + } + else { + assert(0); + } +} + + + +/* + * The fall time of an input signal to the first stage of a circuit is + * assumed to be same as the fall time of the output signal of two + * inverters connected in series (refer: CACTI 1 Technical report, + * section 6.1.3) + */ + double +Wire::signal_fall_time () +{ + + /* rise time of inverter 1's output */ + double rt; + /* fall time of inverter 2's output */ + double ft; + double timeconst; + + timeconst = (drain_C_(g_tp.min_w_nmos_, NCH, 1, 1, g_tp.cell_h_def) + + drain_C_(min_w_pmos, PCH, 1, 1, g_tp.cell_h_def) + + gate_C(min_w_pmos + g_tp.min_w_nmos_, 0)) * + tr_R_on(min_w_pmos, PCH, 1); + rt = horowitz (0, timeconst, deviceType->Vth/deviceType->Vdd, deviceType->Vth/deviceType->Vdd, FALL) / (deviceType->Vdd - deviceType->Vth); + timeconst = (drain_C_(g_tp.min_w_nmos_, NCH, 1, 1, g_tp.cell_h_def) + + drain_C_(min_w_pmos, PCH, 1, 1, g_tp.cell_h_def) + + gate_C(min_w_pmos + g_tp.min_w_nmos_, 0)) * + tr_R_on(g_tp.min_w_nmos_, NCH, 1); + ft = horowitz (rt, timeconst, deviceType->Vth/deviceType->Vdd, deviceType->Vth/deviceType->Vdd, RISE) / deviceType->Vth; + return ft; +} + + + +double Wire::signal_rise_time () +{ + + /* rise time of inverter 1's output */ + double ft; + /* fall time of inverter 2's output */ + double rt; + double timeconst; + + timeconst = (drain_C_(g_tp.min_w_nmos_, NCH, 1, 1, g_tp.cell_h_def) + + drain_C_(min_w_pmos, PCH, 1, 1, g_tp.cell_h_def) + + gate_C(min_w_pmos + g_tp.min_w_nmos_, 0)) * + tr_R_on(g_tp.min_w_nmos_, NCH, 1); + rt = horowitz (0, timeconst, deviceType->Vth/deviceType->Vdd, deviceType->Vth/deviceType->Vdd, RISE) / deviceType->Vth; + timeconst = (drain_C_(g_tp.min_w_nmos_, NCH, 1, 1, g_tp.cell_h_def) + + drain_C_(min_w_pmos, PCH, 1, 1, g_tp.cell_h_def) + + gate_C(min_w_pmos + g_tp.min_w_nmos_, 0)) * + tr_R_on(min_w_pmos, PCH, 1); + ft = horowitz (rt, timeconst, deviceType->Vth/deviceType->Vdd, deviceType->Vth/deviceType->Vdd, FALL) / (deviceType->Vdd - deviceType->Vth); + return ft; //sec +} + + + +/* Wire resistance and capacitance calculations + * wire width + * + * /__/ + * | | + * | | height = ASPECT_RATIO*wire width (ASPECT_RATIO = 2.2, ref: ITRS) + * |__|/ + * + * spacing between wires in same level = wire width + * spacing between wires in adjacent levels = wire width---this is incorrect, + * according to R.Ho's paper and thesis. ILD != wire width + * + */ + +double Wire::wire_cap (double len /* in m */, bool call_from_outside) +{ + //TODO: this should be consistent with the wire_res in technology file + double sidewall, adj, tot_cap; + double wire_height; + double epsilon0 = 8.8542e-12; + double aspect_ratio, horiz_dielectric_constant, vert_dielectric_constant, miller_value,ild_thickness; + + switch (wire_placement) + { + case outside_mat: + { + aspect_ratio = g_tp.wire_outside_mat.aspect_ratio; + horiz_dielectric_constant = g_tp.wire_outside_mat.horiz_dielectric_constant; + vert_dielectric_constant = g_tp.wire_outside_mat.vert_dielectric_constant; + miller_value = g_tp.wire_outside_mat.miller_value; + ild_thickness = g_tp.wire_outside_mat.ild_thickness; + break; + } + case inside_mat : + { + aspect_ratio = g_tp.wire_inside_mat.aspect_ratio; + horiz_dielectric_constant = g_tp.wire_inside_mat.horiz_dielectric_constant; + vert_dielectric_constant = g_tp.wire_inside_mat.vert_dielectric_constant; + miller_value = g_tp.wire_inside_mat.miller_value; + ild_thickness = g_tp.wire_inside_mat.ild_thickness; + break; + } + default: + { + aspect_ratio = g_tp.wire_local.aspect_ratio; + horiz_dielectric_constant = g_tp.wire_local.horiz_dielectric_constant; + vert_dielectric_constant = g_tp.wire_local.vert_dielectric_constant; + miller_value = g_tp.wire_local.miller_value; + ild_thickness = g_tp.wire_local.ild_thickness; + break; + } + } + + if (call_from_outside) + { + wire_width *= 1e-6; + wire_spacing *= 1e-6; + } + wire_height = wire_width/w_scale*aspect_ratio; + /* + * assuming height does not change. wire_width = width_original*w_scale + * So wire_height does not change as wire width increases + */ + +// capacitance between wires in the same level +// sidewall = 2*miller_value * horiz_dielectric_constant * (wire_height/wire_spacing) +// * epsilon0; + + sidewall = miller_value * horiz_dielectric_constant * (wire_height/wire_spacing) + * epsilon0; + + + // capacitance between wires in adjacent levels + //adj = miller_value * vert_dielectric_constant *w_scale * epsilon0; + //adj = 2*vert_dielectric_constant *wire_width/(ild_thickness*1e-6) * epsilon0; + + adj = miller_value *vert_dielectric_constant *wire_width/(ild_thickness*1e-6) * epsilon0; + //Change ild_thickness from micron to M + + //tot_cap = (sidewall + adj + (deviceType->C_fringe * 1e6)); //F/m + tot_cap = (sidewall + adj + (g_tp.fringe_cap * 1e6)); //F/m + + if (call_from_outside) + { + wire_width *= 1e6; + wire_spacing *= 1e6; + } + return (tot_cap*len); // (F) +} + + + double +Wire::wire_res (double len /*(in m)*/) +{ + + double aspect_ratio,alpha_scatter =1.05, dishing_thickness=0, barrier_thickness=0; + //TODO: this should be consistent with the wire_res in technology file + //The whole computation should be consistent with the wire_res in technology.cc too! + + switch (wire_placement) + { + case outside_mat: + { + aspect_ratio = g_tp.wire_outside_mat.aspect_ratio; + break; + } + case inside_mat : + { + aspect_ratio = g_tp.wire_inside_mat.aspect_ratio; + break; + } + default: + { + aspect_ratio = g_tp.wire_local.aspect_ratio; + break; + } + } + return (alpha_scatter * resistivity * 1e-6 * len/((aspect_ratio*wire_width/w_scale-dishing_thickness - barrier_thickness)* + (wire_width-2*barrier_thickness))); +} + +/* + * Calculates the delay, power and area of the transmitter circuit. + * + * The transmitter delay is the sum of nand gate delay, inverter delay + * low swing nmos delay, and the wire delay + * (ref: Technical report 6) + */ + void +Wire::low_swing_model() +{ + double len = wire_length; + double beta = pmos_to_nmos_sz_ratio(); + + + double inputrise = (in_rise_time == 0) ? signal_rise_time() : in_rise_time; + + /* Final nmos low swing driver size calculation: + * Try to size the driver such that the delay + * is less than 8FO4. + * If the driver size is greater than + * the max allowable size, assume max size for the driver. + * In either case, recalculate the delay using + * the final driver size assuming slow input with + * finite rise time instead of ideal step input + * + * (ref: Technical report 6) + */ + double cwire = wire_cap(len); /* load capacitance */ + double rwire = wire_res(len); + +#define RES_ADJ (8.6) // Increase in resistance due to low driving vol. + + double driver_res = (-8*g_tp.FO4/(log(0.5) * cwire))/RES_ADJ; + double nsize = R_to_w(driver_res, NCH); + + nsize = MIN(nsize, g_tp.max_w_nmos_); + nsize = MAX(nsize, g_tp.min_w_nmos_); + + if(rwire*cwire > 8*g_tp.FO4) + { + nsize = g_tp.max_w_nmos_; + } + + // size the inverter appropriately to minimize the transmitter delay + // Note - In order to minimize leakage, we are not adding a set of inverters to + // bring down delay. Instead, we are sizing the single gate + // based on the logical effort. + double st_eff = sqrt((2+beta/1+beta)*gate_C(nsize, 0)/(gate_C(2*g_tp.min_w_nmos_, 0) + + gate_C(2*min_w_pmos, 0))); + double req_cin = ((2+beta/1+beta)*gate_C(nsize, 0))/st_eff; + double inv_size = req_cin/(gate_C(min_w_pmos, 0) + gate_C(g_tp.min_w_nmos_, 0)); + inv_size = MAX(inv_size, 1); + + /* nand gate delay */ + double res_eq = (2 * tr_R_on(g_tp.min_w_nmos_, NCH, 1)); + double cap_eq = 2 * drain_C_(min_w_pmos, PCH, 1, 1, g_tp.cell_h_def) + + drain_C_(2*g_tp.min_w_nmos_, NCH, 1, 1, g_tp.cell_h_def) + + gate_C(inv_size*g_tp.min_w_nmos_, 0) + + gate_C(inv_size*min_w_pmos, 0); + + double timeconst = res_eq * cap_eq; + + delay = horowitz(inputrise, timeconst, deviceType->Vth/deviceType->Vdd, + deviceType->Vth/deviceType->Vdd, RISE); + double temp_power = cap_eq*deviceType->Vdd*deviceType->Vdd; + + inputrise = delay / (deviceType->Vdd - deviceType->Vth); /* for the next stage */ + + /* Inverter delay: + * The load capacitance of this inv depends on + * the gate capacitance of the final stage nmos + * transistor which in turn depends on nsize + */ + res_eq = tr_R_on(inv_size*min_w_pmos, PCH, 1); + cap_eq = drain_C_(inv_size*min_w_pmos, PCH, 1, 1, g_tp.cell_h_def) + + drain_C_(inv_size*g_tp.min_w_nmos_, NCH, 1, 1, g_tp.cell_h_def) + + gate_C(nsize, 0); + timeconst = res_eq * cap_eq; + + delay += horowitz(inputrise, timeconst, deviceType->Vth/deviceType->Vdd, + deviceType->Vth/deviceType->Vdd, FALL); + temp_power += cap_eq*deviceType->Vdd*deviceType->Vdd; + + + transmitter.delay = delay; + transmitter.power.readOp.dynamic = temp_power*2; /* since it is a diff. model*/ + transmitter.power.readOp.leakage = deviceType->Vdd * + (4 * cmos_Isub_leakage(g_tp.min_w_nmos_, min_w_pmos, 2, nand) + + 4 * cmos_Isub_leakage(g_tp.min_w_nmos_, min_w_pmos, 1, inv)); + + transmitter.power.readOp.gate_leakage = deviceType->Vdd * + (4 * cmos_Ig_leakage(g_tp.min_w_nmos_, min_w_pmos, 2, nand) + + 4 * cmos_Ig_leakage(g_tp.min_w_nmos_, min_w_pmos, 1, inv)); + + inputrise = delay / deviceType->Vth; + + /* nmos delay + wire delay */ + cap_eq = cwire + drain_C_(nsize, NCH, 1, 1, g_tp.cell_h_def)*2 + + nsense * sense_amp_input_cap(); //+receiver cap + /* + * NOTE: nmos is used as both pull up and pull down transistor + * in the transmitter. This is because for low voltage swing, drive + * resistance of nmos is less than pmos + * (for a detailed graph ref: On-Chip Wires: Scaling and Efficiency) + */ + timeconst = (tr_R_on(nsize, NCH, 1)*RES_ADJ) * (cwire + + drain_C_(nsize, NCH, 1, 1, g_tp.cell_h_def)*2) + + rwire*cwire/2 + + (tr_R_on(nsize, NCH, 1)*RES_ADJ + rwire) * + nsense * sense_amp_input_cap(); + + /* + * since we are pre-equalizing and overdriving the low + * swing wires, the net time constant is less + * than the actual value + */ + delay += horowitz(inputrise, timeconst, deviceType->Vth/deviceType->Vdd, .25, 0); +#define VOL_SWING .1 + temp_power += cap_eq*VOL_SWING*.400; /* .4v is the over drive voltage */ + temp_power *= 2; /* differential wire */ + + l_wire.delay = delay - transmitter.delay; + l_wire.power.readOp.dynamic = temp_power - transmitter.power.readOp.dynamic; + l_wire.power.readOp.leakage = deviceType->Vdd* + (4* cmos_Isub_leakage(nsize, 0, 1, nmos)); + + l_wire.power.readOp.gate_leakage = deviceType->Vdd* + (4* cmos_Ig_leakage(nsize, 0, 1, nmos)); + + //double rt = horowitz(inputrise, timeconst, deviceType->Vth/deviceType->Vdd, + // deviceType->Vth/deviceType->Vdd, RISE)/deviceType->Vth; + + delay += g_tp.sense_delay; + + sense_amp.delay = g_tp.sense_delay; + out_rise_time = g_tp.sense_delay/(deviceType->Vth); + sense_amp.power.readOp.dynamic = g_tp.sense_dy_power; + sense_amp.power.readOp.leakage = 0; //FIXME + sense_amp.power.readOp.gate_leakage = 0; + + power.readOp.dynamic = temp_power + sense_amp.power.readOp.dynamic; + power.readOp.leakage = transmitter.power.readOp.leakage + + l_wire.power.readOp.leakage + + sense_amp.power.readOp.leakage; + power.readOp.gate_leakage = transmitter.power.readOp.gate_leakage + + l_wire.power.readOp.gate_leakage + + sense_amp.power.readOp.gate_leakage; +} + + double +Wire::sense_amp_input_cap() +{ + return drain_C_(g_tp.w_iso, PCH, 1, 1, g_tp.cell_h_def) + + gate_C(g_tp.w_sense_en + g_tp.w_sense_n, 0) + + drain_C_(g_tp.w_sense_n, NCH, 1, 1, g_tp.cell_h_def) + + drain_C_(g_tp.w_sense_p, PCH, 1, 1, g_tp.cell_h_def); +} + + +void Wire::delay_optimal_wire () +{ + double len = wire_length; + //double min_wire_width = wire_width; //m + double beta = pmos_to_nmos_sz_ratio(); + double switching = 0; // switching energy + double short_ckt = 0; // short-circuit energy + double tc = 0; // time constant + // input cap of min sized driver + double input_cap = gate_C(g_tp.min_w_nmos_ + min_w_pmos, 0); + + // output parasitic capacitance of + // the min. sized driver + double out_cap = drain_C_(min_w_pmos, PCH, 1, 1, g_tp.cell_h_def) + + drain_C_(g_tp.min_w_nmos_, NCH, 1, 1, g_tp.cell_h_def); + // drive resistance + double out_res = (tr_R_on(g_tp.min_w_nmos_, NCH, 1) + + tr_R_on(min_w_pmos, PCH, 1))/2; + double wr = wire_res(len); //ohm + + // wire cap /m + double wc = wire_cap(len); + + // size the repeater such that the delay of the wire is minimum + double repeater_scaling = sqrt(out_res*wc/(wr*input_cap)); // len will cancel + + // calc the optimum spacing between the repeaters (m) + + repeater_spacing = sqrt(2 * out_res * (out_cap + input_cap)/ + ((wr/len)*(wc/len))); + repeater_size = repeater_scaling; + + switching = (repeater_scaling * (input_cap + out_cap) + + repeater_spacing * (wc/len)) * deviceType->Vdd * deviceType->Vdd; + + tc = out_res * (input_cap + out_cap) + + out_res * wc/len * repeater_spacing/repeater_scaling + + wr/len * repeater_spacing * input_cap * repeater_scaling + + 0.5 * (wr/len) * (wc/len)* repeater_spacing * repeater_spacing; + + delay = 0.693 * tc * len/repeater_spacing; + +#define Ishort_ckt 65e-6 /* across all tech Ref:Banerjee et al. {IEEE TED} */ + short_ckt = deviceType->Vdd * g_tp.min_w_nmos_ * Ishort_ckt * 1.0986 * + repeater_scaling * tc; + + area.set_area((len/repeater_spacing) * + compute_gate_area(INV, 1, min_w_pmos * repeater_scaling, + g_tp.min_w_nmos_ * repeater_scaling, g_tp.cell_h_def)); + power.readOp.dynamic = ((len/repeater_spacing)*(switching + short_ckt)); + power.readOp.leakage = ((len/repeater_spacing)* + deviceType->Vdd* + cmos_Isub_leakage(g_tp.min_w_nmos_*repeater_scaling, beta*g_tp.min_w_nmos_*repeater_scaling, 1, inv)); + power.readOp.gate_leakage = ((len/repeater_spacing)* + deviceType->Vdd* + cmos_Ig_leakage(g_tp.min_w_nmos_*repeater_scaling, beta*g_tp.min_w_nmos_*repeater_scaling, 1, inv)); +} + + + +// calculate power/delay values for wires with suboptimal repeater sizing/spacing +void +Wire::init_wire(){ + wire_length = 1; + delay_optimal_wire(); + double sp, si; + powerDef pow; + si = repeater_size; + sp = repeater_spacing; + sp *= 1e6; // in microns + + double i, j, del; + repeated_wire.push_back(Component()); + for (j=sp; j < 4*sp; j+=100) { + for (i = si; i > 1; i--) { + pow = wire_model(j*1e-6, i, &del); + if (j == sp && i == si) { + global.delay = del; + global.power = pow; + global.area.h = si; + global.area.w = sp*1e-6; // m + } +// cout << "Repeater size - "<< i << +// " Repeater spacing - " << j << +// " Delay - " << del << +// " PowerD - " << pow.readOp.dynamic << +// " PowerL - " << pow.readOp.leakage <<endl; + repeated_wire.back().delay = del; + repeated_wire.back().power.readOp = pow.readOp; + repeated_wire.back().area.w = j*1e-6; //m + repeated_wire.back().area.h = i; + repeated_wire.push_back(Component()); + + } + } + repeated_wire.pop_back(); + update_fullswing(); + Wire *l_wire = new Wire(Low_swing, 0.001/* 1 mm*/, 1); + low_swing.delay = l_wire->delay; + low_swing.power = l_wire->power; + delete l_wire; +} + + + +void Wire::update_fullswing() +{ + + list<Component>::iterator citer; + double del[4]; + del[3] = this->global.delay + this->global.delay*.3; + del[2] = global.delay + global.delay*.2; + del[1] = global.delay + global.delay*.1; + del[0] = global.delay + global.delay*.05; + double threshold; + double ncost; + double cost; + int i = 4; + while (i>0) { + threshold = del[i-1]; + cost = BIGNUM; + for (citer = repeated_wire.begin(); citer != repeated_wire.end(); citer++) + { + if (citer->delay > threshold) { + citer = repeated_wire.erase(citer); + citer --; + } + else { + ncost = citer->power.readOp.dynamic/global.power.readOp.dynamic + + citer->power.readOp.leakage/global.power.readOp.leakage; + if(ncost < cost) + { + cost = ncost; + if (i == 4) { + global_30.delay = citer->delay; + global_30.power = citer->power; + global_30.area = citer->area; + } + else if (i==3) { + global_20.delay = citer->delay; + global_20.power = citer->power; + global_20.area = citer->area; + } + else if(i==2) { + global_10.delay = citer->delay; + global_10.power = citer->power; + global_10.area = citer->area; + } + else if(i==1) { + global_5.delay = citer->delay; + global_5.power = citer->power; + global_5.area = citer->area; + } + } + } + } + i--; + } +} + + + +powerDef Wire::wire_model (double space, double size, double *delay) +{ + powerDef ptemp; + double len = 1; + //double min_wire_width = wire_width; //m + double beta = pmos_to_nmos_sz_ratio(); + // switching energy + double switching = 0; + // short-circuit energy + double short_ckt = 0; + // time constant + double tc = 0; + // input cap of min sized driver + double input_cap = gate_C (g_tp.min_w_nmos_ + + min_w_pmos, 0); + + // output parasitic capacitance of + // the min. sized driver + double out_cap = drain_C_(min_w_pmos, PCH, 1, 1, g_tp.cell_h_def) + + drain_C_(g_tp.min_w_nmos_, NCH, 1, 1, g_tp.cell_h_def); + // drive resistance + double out_res = (tr_R_on(g_tp.min_w_nmos_, NCH, 1) + + tr_R_on(min_w_pmos, PCH, 1))/2; + double wr = wire_res(len); //ohm + + // wire cap /m + double wc = wire_cap(len); + + repeater_spacing = space; + repeater_size = size; + + switching = (repeater_size * (input_cap + out_cap) + + repeater_spacing * (wc/len)) * deviceType->Vdd * deviceType->Vdd; + + tc = out_res * (input_cap + out_cap) + + out_res * wc/len * repeater_spacing/repeater_size + + wr/len * repeater_spacing * out_cap * repeater_size + + 0.5 * (wr/len) * (wc/len)* repeater_spacing * repeater_spacing; + + *delay = 0.693 * tc * len/repeater_spacing; + +#define Ishort_ckt 65e-6 /* across all tech Ref:Banerjee et al. {IEEE TED} */ + short_ckt = deviceType->Vdd * g_tp.min_w_nmos_ * Ishort_ckt * 1.0986 * + repeater_size * tc; + + ptemp.readOp.dynamic = ((len/repeater_spacing)*(switching + short_ckt)); + ptemp.readOp.leakage = ((len/repeater_spacing)* + deviceType->Vdd* + cmos_Isub_leakage(g_tp.min_w_nmos_*repeater_size, beta*g_tp.min_w_nmos_*repeater_size, 1, inv)); + + ptemp.readOp.gate_leakage = ((len/repeater_spacing)* + deviceType->Vdd* + cmos_Ig_leakage(g_tp.min_w_nmos_*repeater_size, beta*g_tp.min_w_nmos_*repeater_size, 1, inv)); + + return ptemp; +} + +void +Wire::print_wire() +{ + + cout << "\nWire Properties:\n\n"; + cout << " Delay Optimal\n\tRepeater size - "<< global.area.h << + " \n\tRepeater spacing - " << global.area.w*1e3 << " (mm)" + " \n\tDelay - " << global.delay*1e6 << " (ns/mm)" + " \n\tPowerD - " << global.power.readOp.dynamic *1e6<< " (nJ/mm)" + " \n\tPowerL - " << global.power.readOp.leakage << " (mW/mm)" + " \n\tPowerLgate - " << global.power.readOp.gate_leakage << " (mW/mm)\n"; + cout << "\tWire width - " <<wire_width_init*1e6 << " microns\n"; + cout << "\tWire spacing - " <<wire_spacing_init*1e6 << " microns\n"; + cout <<endl; + + cout << " 5% Overhead\n\tRepeater size - "<< global_5.area.h << + " \n\tRepeater spacing - " << global_5.area.w*1e3 << " (mm)" + " \n\tDelay - " << global_5.delay *1e6<< " (ns/mm)" + " \n\tPowerD - " << global_5.power.readOp.dynamic *1e6<< " (nJ/mm)" + " \n\tPowerL - " << global_5.power.readOp.leakage << " (mW/mm)" + " \n\tPowerLgate - " << global_5.power.readOp.gate_leakage << " (mW/mm)\n"; + cout << "\tWire width - " <<wire_width_init*1e6 << " microns\n"; + cout << "\tWire spacing - " <<wire_spacing_init*1e6 << " microns\n"; + cout <<endl; + cout << " 10% Overhead\n\tRepeater size - "<< global_10.area.h << + " \n\tRepeater spacing - " << global_10.area.w*1e3 << " (mm)" + " \n\tDelay - " << global_10.delay *1e6<< " (ns/mm)" + " \n\tPowerD - " << global_10.power.readOp.dynamic *1e6<< " (nJ/mm)" + " \n\tPowerL - " << global_10.power.readOp.leakage << " (mW/mm)" + " \n\tPowerLgate - " << global_10.power.readOp.gate_leakage << " (mW/mm)\n"; + cout << "\tWire width - " <<wire_width_init*1e6 << " microns\n"; + cout << "\tWire spacing - " <<wire_spacing_init*1e6 << " microns\n"; + cout <<endl; + cout << " 20% Overhead\n\tRepeater size - "<< global_20.area.h << + " \n\tRepeater spacing - " << global_20.area.w*1e3 << " (mm)" + " \n\tDelay - " << global_20.delay *1e6<< " (ns/mm)" + " \n\tPowerD - " << global_20.power.readOp.dynamic *1e6<< " (nJ/mm)" + " \n\tPowerL - " << global_20.power.readOp.leakage << " (mW/mm)" + " \n\tPowerLgate - " << global_20.power.readOp.gate_leakage << " (mW/mm)\n"; + cout << "\tWire width - " <<wire_width_init*1e6 << " microns\n"; + cout << "\tWire spacing - " <<wire_spacing_init*1e6 << " microns\n"; + cout <<endl; + cout << " 30% Overhead\n\tRepeater size - "<< global_30.area.h << + " \n\tRepeater spacing - " << global_30.area.w*1e3 << " (mm)" + " \n\tDelay - " << global_30.delay *1e6<< " (ns/mm)" + " \n\tPowerD - " << global_30.power.readOp.dynamic *1e6<< " (nJ/mm)" + " \n\tPowerL - " << global_30.power.readOp.leakage << " (mW/mm)" + " \n\tPowerLgate - " << global_30.power.readOp.gate_leakage << " (mW/mm)\n"; + cout << "\tWire width - " <<wire_width_init*1e6 << " microns\n"; + cout << "\tWire spacing - " <<wire_spacing_init*1e6 << " microns\n"; + cout <<endl; + cout << " Low-swing wire (1 mm) - Note: Unlike repeated wires, \n\tdelay and power " + "values of low-swing wires do not\n\thave a linear relationship with length." << + " \n\tdelay - " << low_swing.delay *1e9<< " (ns)" + " \n\tpowerD - " << low_swing.power.readOp.dynamic *1e9<< " (nJ)" + " \n\tPowerL - " << low_swing.power.readOp.leakage << " (mW)" + " \n\tPowerLgate - " << low_swing.power.readOp.gate_leakage << " (mW)\n"; + cout << "\tWire width - " <<wire_width_init * 2 /* differential */<< " microns\n"; + cout << "\tWire spacing - " <<wire_spacing_init * 2 /* differential */<< " microns\n"; + cout <<endl; + cout <<endl; + +} + |