Zroute Technical Tutorial v2 03 024524

8/8/2019 Zroute Technical Tutorial v2 03 024524

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CONFIDENTIAL INFORMATION

non-disclosure agreement between you or your employer andSynopsys. Information disclosed in this presentation shall be

.

LEGAL NOTICEInformation contained in this presentation reflects Synopsysplans as of the date of this presentation. Such plans are subject tocom letion and are sub ect to chan e. Products shall be offered

and purchased only pursuant to an authorized quote andpurchase order. Synopsys is not obligated to develop the

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materials.


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Agenda

Z

Z

Basic Zroute Flow Overview

Multi-Threaded Routing

E

E

Summary

Note that the a endix has additional details about ettin started

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Introducing ZrouteArchitected From The Ground Up For New Challenges

State-of-the-art routingtechnology

I omp eromp erI omp eromp erConcurrent DFM optimizations

2

rou erou erou erou e

Multi-threaded throughout3

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-- ,, ,,


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1. State-of-the-Art Routing Technology

Dynamic Maze GridRealistic Connectivity

Virtual Wire

DynamicGrid

Advanced Design Rules Polygon ManagerY

ZX

SSW

0.6S

0.6S

51-

,,


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2. Concurrent DFM Optimizations

Redundant ViasSoft Rulesld

Yie

S T

Antennas Wire Spreading/Widening

SpacingS T

Metal 1

Gate

Via1Metal 2

Metal 1Via1

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,,


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3. Multi-Threaded Throughout

ScalabilityAll Routing Steps

Global Routing

Track AssignmentX Speedup

Larger CapacityTransparent

# of cores

MemoryNative

Ready to go-

# of cores

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,,


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10X Speed-Up On Mainstream Hardware

3.5X Faster3.5X Faster SingleSingle- -threadedthreadedxx

pee uppee up uu -- rea e on ua orerea e on ua ore

10X Speed Up10X Speed Up

achieved a 10x boost in performancewhen we used it with a quad-core platform.

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10X Speed-Up On Mainstream Hardware

33--4X4X 3X3XMulti-threaded

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Fewer Wires, Fewer Total Number of Vias

1010--15%15%11--2%2%Wire Length # of Total Vias

40nm, 60K

40nm, 225K

65nm, 845K

45nm, 374K

65nm, 845K

45nm, 170K

65nm, 545K

65nm, 593K

65nm, 545K

65nm, 593K

80nm, 2777K

65nm, 356K

0 1 2 3

65nm, 356K

0 10 20

90nm, 2313K

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Fewer Non-Optimized Single Vias

3030--50%50%Remaining Non-Optimized Single Vias

40nm, 93K

40nm, 225K

45nm, 374K

40nm, 60K

65nm, 1000K

45nm, 170K

0 10 20 30 40 50 60 70

65nm, 68K

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Fewer Jogs and Notches,

Improved LithographyLitho-Friendly Routing

No Scenic Routes

Fewer Jogs

Fewer Notches

70% fewer narrow jogs30% fewer notches

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Zroute Results on Customer Designs

Technology # of Cells Utilization Runtime Wire Length Contacts

90 870 59 3.3 6% 3%65 67 85 1.5 2% 9%

.

65 1000 75 2 0% 2%

45 50 63 9 6% 19%.

45 93 80 1.3 4% 5%

45 170 72 3.8 1% 25%

.45 374 61 3 4% 17.8%

3X3X

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Zroute Is GA in IC Compiler B-2008.09!

A-2007.12-SP5-1

A-2007.12-SP5-1

Multiple on-going-

Multiple on-going-

1000+1000+Multiple planned

test chips at 32nmMultiple planned

test chips at 32nmhitshits

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Zroute Users Tell The Story

2-3.4X faster single-threaded3X scalability with 4 threads ...

70% fewer narrow jogs,30% fewer notches ...

tapes out home networking deviceusin new Zroute technolo

9/22/08

achieved a 10X boost in performance

9/15/08

routing runtimes cut significantly by

- .5/27/08

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- 5/19/08


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Zroute Technology SummaryArchitected From The Ground Up For New Challenges

AvailableAvailable

State of the art technologyPart of IC CompilerPart of IC CompilerBB--2008.092008.09

Concurrent DFM optimizations2CoCo--exists with current routerexists with current router

I omp eromp erI omp eromp er

Multi-threaded throughout3

Single license for 4 coresSingle license for 4 cores

rou erou erou erou e

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-- ,, ,,


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Agenda

ZZ



EE

Summary

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Currently Supported Design Rules

All 65nm and above design rules

Most 45/40nm rules

Common Platform and TSMC 45/40nm design rules

Selected IDMs 45nm rules

OO

Zroute supports only design rules defined in the

yway tec no ogy eClassic router parameters used to implement design

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rules must be migrated to the technology file


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Zroute Input and Output

Same inputs as classic router

Milkyway design library

Technology file

Standard cell and macro cell FRAM view

Route guides, layer constraints, nondefault rules

Power nets routed with power and ground prerouter

Output - routing data generated in the Milkyway

CEL viewopen_mw_cel, save_mw_cel

S

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Sreport_design physical


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Basic Zroute Flow

SetSet ZrouteZroute as Targeted Routeras Targeted Router

PostPost- -CTS CellCTS Cell

set_route_mode_options zroute true

SetSet ZrouteZroute OptionsOptions Includes translating classic router parametersinto Zroute options

Route ClocksRoute Clocks Integrated clock global router (ICGR) withroute_zrt_group

Route SignalsRoute Signals

PostroutePostroute O timizationsO timizations

route_opt initial_route_only

route_opt skip_initial_routeroute o t incremental

Chip FinishingChip Finishing

_

201-signoff_optsignoff_opt


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More on report_route_opt_strategy

Classic Router*********************************************************

Zroute*********************************************************

route_opt strategy for the design:

Fix Hold Mode : route_base

Search-Repair loops : 15

route_opt strategy for the design:

Fix Hold Mode : route_base

Search-Repair loops : 10

ECO Search-Repair loops : 5

Optimize Wire/Via Search-Repair loops : 5

Optimize Wire/Via CPU limit : -1

ECO Search-Repair loops : 4

Optimize Wire/Via Search-Repair loops : N/A

Optimize Wire/Via CPU limit : N/A

Route Violation threshold : 3000

*********************************************************

Route Violation threshold : 3000

*********************************************************

De au era ons are an or rou e- aseroute_optZroute conver es uicker

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Zroute is more intelligent, stopping on nonconvergence


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Zroute Versus Classic Router Commands

Commands do not match 1:1 due to differentrouting architecture

Zroute Classic routerroute_zrt_global route_global

_ _ _

route_zrt_detailroute_zrt_detail incremental true

route_detailroute_search_repair

_ _ _

route_zrt_auto route_auto

route_zrt_eco* route_eco

insert_zrt_redundant_vias insert_redundant_viasn/a optimize_wire_via

extract zrt hier antenna property extract hier antenna property

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_

*Zroute must use ECO route if there are opens!


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Zroute Options

Zroute option setup commandsset route zrt common o tions

set_route_zrt_global_optionsset_route_zrt_track_options

set_route_zrt_detail_options

Commands to report Zroute optionsreport_route_zrt_*_options

Commands to query Zroute option values

get_route_zrt_*_options -name option_nameAll options are persistent (saved with design)

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* common|detail|global|track


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Intelligent DRC Convergence

For each iteration after the initial iteration, Zrouteanalyzes the DRC distribution

Different areas can use different partition size and aspectratio (nonuniform partitions)

ZZInitial iterations use simple methods to fix most violations

Subse uent iterations use more advanced methods

Zroute can weight violation types differently foreach iteration

After iteration 30, costs are not changed

Zroute detects nonconvergence of DRC and stops

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iterations

You do not have to limit iterations to improve runtime


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Center Line Connectivity

Classic router depends on center line connectivityZroute does notCC

to meet DRCs

261-Center line is not connected Center line is connected


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Dont Do

Dont run verify_route on Zroute designClassic router has a different connectivity model (center lineconnection which affects o en re ortin and DRC calculationsUse verify_zrt_route to verify Zroute resultsUse verify_drc (65nm or above), signoff_drc (B-2008.09 or laterreleases), or Hercules to independently verify the router result

Dont use report_antenna_ratio to report antenna

violations, use verify_zrt_route antenna trueDont run classic router AFTER Zroute

You will get the following error if you try to do this:

commands after Zroute commands. (RT-302)Can run classic router before Zroute

For exam le, usin route rou for clocks

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_


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verify_zrt_route : Summary

verify_zrt_route outputs summary at the endI op on s a se, summary repor s no c ec e

Use -report_all_open_nets true to list all opensSS

Verify Summary:

Total number of nets = 229823, of which 0 are not extracted

Total number of open nets = 0, of which 0 are frozen

Total number of excluded ports =

0 ports of 0 unplaced cells connected to 0 nets

-open_net

0 ports without pins of 0 cells connected to 0 nets

0 ports of 0 cover cells connected to 0 non-pg nets

Total num of DRCs = 5

Total num of antenna violations = 0

-drc

-antenna

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Total num of voltage-area violations = not checked-voltage_area

# | no antenna rules defined | not checked


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Switching to Zroute in the GUI

Select Zroute Mode check box or useset route mode o tions zroute true_ _ _

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Has Design Been Routed by Zroute?

set_route_mode_options zroute true onlyshows user intent

Tells commands that use embedded routing to useZroute as the router D

To query if Zroute has been run on a design, use_ _ _

Yes:Message: Design is routed using Zroute.

Returns: trueNo:

M

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M .Returns: false


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Agenda

ZZ



EE

Summary

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Multi-Threaded Routing Throughout

Designed from ground up as a multi-threaded routerMost route engines run multi-threaded tasksG

Need multi-CPU or multi-core machines to run

Number of threads total number of cores

DDMulti-threading: Multiple CPUs performing parallel algorithmson the same machine using a single process memory

Distributed: Partition design and send each partition to aseparate CPU with separate memory image of routing task

T

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T -set_route_zrt_common_options max_number_of_threads 2


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Measuring Multi-Threaded Routing

Speed-up should be measured by using wall-clock time,not total CPU time (Example is 8 threads)

[GR: Done] Elapsed real time: 0:09:11

[GR: Done] Elapsed cpu time: sys=0:01:21 usr=0:41:02 total= 0:42:23[Track Assign: Done] Elapsed real time: 0:05:57[Track Assign: Done] Elapsed cpu time: sys=0:00:50 usr=0:38:30 total= 0:39:21[DR Done] Elapsed real time: 0:17:50

[DR Done] Elapsed cpu time: sys=0:00:01 usr=2:21:07 total= 2:21:09

In general, memory should be compared by using asingle process

Total Memory = main process memory + child processmemory, easier just to turn off child process for router T

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Tset_app_var physopt_enable_router_process false

Example: Runtime Improvement


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Example: Runtime Improvement90nm, 2.3M Instances, 578 Macros

QoR

Memory reduction21.6GB vs. 16.9GB2

7.0

8.0

classic

Zroute

2.1XClassic versus Zroute

2 .

Wire length improvement

1.8%3.04.0

5.0

6.0

e: H

ours

1.

1.7XVia reduction

11.6%0.0

1.0

2.0Runti

Redundant via rateimprovement72.7% vs 93%

rou e_au o n ser _re u n an v as ver y_rou e

Single CPU/Thread

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Example: Multi Threading Speed Up


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Example: Multi-Threading Speed-Up90nm, 2.3M Instances, 578 Macros

Comparing Threadability of Commands

200.0

.

5.2X

150.0

nutes

1

2

2.8X

50.0

100.0

Runtime: Mi

84.7X

0.0

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_ _ _

*Run on 4 dual-core CPUs

Example: Multi Threading Speed up


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Example: Multi-Threading Speed-up90nm, 2.3M Instances, 578 Macros

140.0

Comparing Threadability Insideroute_zrt_auto

120.0

6.9X

80.0

.

nutes

1

2

5.1X

40.0

60.0

Runtime: Mi

83.3X

0.0

20.0

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global track detail

*Run on 4 dual-core CPUs


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Agenda

ZZ



EE

Summary

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Parameter Translator Example

See the parameter translator guide (SolvNet 024478)for more info

un c ass c rou er scr p up o po n o runn ng c ass c rou er

##Translate parameterstranslate_zrt_parameters

Parameters translated into Zroute o tions =========================================

Translated ignoreNotchDRC of droute 0 to set_route_zrt_detail_options-ignore_drc {{same_net_metal_space false}}

Translated runTimingMode of trackAssign 1 to set_route_zrt_track_options-timing_driven true

Parameters not translated=========================

.

(ZRT-410)Warning: droute parameter accessPolyPin is not supported by Zroute.

(ZRT-409)Warning: droute parameter dropVia1InsideM1Pin cannot be translated

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rou e op on. -Warning: droute parameter M1FloatingSpaceForViaOffLimit is supported by

Zroute only in Milkyway technology file . (ZRT-411)

Wi h Z E l


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route_opt With Zroute Example

##Assume clocks are already routed

##Set signal integrity optionsse _s _op ons - e a_ e ay rue

-route_xtalk_prevention true \

-route_xtalk_prevention_threshold 0.25

Ena e Zroute ns e route_optset_route_mode_options -zroute true

##Turn on multi-threadingset_route_zrt_common_opt ons -max_num er_o _t rea s

##Add specific Zroute options as needed#set_route_zrt_*_options

##Run initial routingroute_opt initial_route_only

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Perform postroute optimizationsroute_opt skip_initial_route

t t t SI d Ti i D i


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route_zrt_auto : SI and Timing Driven

##Set signal integrity optionsset_route_zrt_common_options -threshold_noise_ratio 0.25set_route_zrt_global_options -crosstalk_driven true

_ _ _ _ _

##Tell tool to use Zrouteset_route_mode_options zroute true

##Add specific Zroute options as needed#set_route_zrt_xxx_options

set_route_zrt_global_options -timing_driven true

set_route_zrt_track_options -timing_driven trueset_route_zrt_detail_options -timing_driven true route_opt

##Route designroute_zrt_auto -max_detail_route_iterations 10

_ _

defaults

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verify_zrt_route

report_design -physical

ICGR Fl With Z t E l


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ICGR Flow With Zroute Example

##Set clock tree referencesset_clock_tree_references

##Set clock net routing rulesset_clock_tree_options -routing_rule XYZ layer_list upper_layers

##Turn on ICGR inside CTOset_app_var cto_2007_12 true

set_delay_calculation -clock_arnoldi

##2008.09 Flowset_delay_calculation clock_arnoldi

##Run CTS and CTOclock_opt only_cts no_clock_route

##Route clocks using the previous ICGR global route

clock_opt only_cts \cts_effort high no_clock_route

route_zrt_group all_clock_nets -reuse_existing_global_route true

Prior to B-2008.09-SP3 useset_route_zrt_global_options -incremental true

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route_zrt_group all_clock_netsset_route_zrt_global_options -incremental false

Note: In B-2008.09-SP3, the global options are hiddenand work, but will be removed for the C-2009.06 release.

A t Fi i g ith L H i g


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Antenna Fixing with Layer Hopping

Concurrent ow y e au t##Load design antenna rules (stored in design library)source antenna rules.tcl _

##Run initial routingroute_opt initial_route_only

##Perform postroute optimizationsroute_opt skip_initial_route

##Verif routin antenna checkin on b default

verify_zrt_route

Zroute scripts should explicitly turn off antenna

fixing and checking if not neededset_route_zrt_detail_options -antenna falseverify_zrt_route antenna false

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Classic router scripts tended to turn antennas on

sequentially

insert zrt redundant vias list only


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insert_zrt_redundant_vias list_only

Redundant via optimization will attempt to replace the following vias:

VIA12 -> VIA12_2x1(r) VIA12_2x1 VIA12_1x2(r) VIA12_1x2- _ _ _ _

VIA23 -> VIA23_1x2 VIA23_1x2(r) VIA23_2x1 VIA23_2x1(r)VIA23(r) -> VIA23_1x2 VIA23_1x2(r) VIA23_2x1 VIA23_2x1(r)......

_ _ _-from_via { VIA12 VIA23 VIA34 VIA45 VIA56 VIA12_OPTI VIA23_OPTI VIA34_OPTI \

VIA45_OPTI VIA56_OPTI VIA12_OPTI_SQ VIA23_OPTI_SQ VIA34_OPTI_SQ VIA45_OPTI_SQ \VIA56_OPTI_SQ VIA67 VIA78 } \

-to_via { VIA12 VIA23 VIA34 VIA45 VIA56 VIA12 VIA23 VIA34 \ VIA56 VIA67 VIA78 } \

-to_via_x_size { 2 2 2 2 2 2 2 2 \2 2 2 2 2 2 \2 2 2 } \

- _ _ _

1 1 1 1 1 1 \1 1 1 } \

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Prioritizing Double and Single VIA for DFM


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Prioritizing Double and Single VIA for DFMHidden 2008.09-SP2

- -

Some vias may be better for DFM, while others are

- . -SP4

b

Use define_zrt_redundant_vias -to_via_weights {}

Weight is 1 to 10

Higher weight via will be tried firstEqual weights, Zroute will prioritize based on routability

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Insert Redundant Vias


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##Define redundant via sets (optional)

Initial Release FlowNot persistent, set

in any script in_ _ _

##Route designset_route_mode_options zroute true

wredundant vias

_ _ _

##Insert double vias before timing optinsert_zrt_redundant_vias


insert_zrt_redundant_vias

##Report double-via rate per layer

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repor _ es gn -p ys ca



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##Define redundant via sets (optional)

Concurrent Flow

_ _ _

##Reserve room for redundant viasset_route_zrt_common_options \

- concurrent_redundant_via_mode reserve_space

##Enable postroute redundant via insertion

set_route_zrt_common_options \

Ena ena e pos rou epos rou eredundant viaredundant via

insertion at end of insertion at end of routin hasesroutin hases-post_detail_route_redundant_via_insertion medium

##Route designset_route_mode_options zroute true RedundantRedundant viasviasroute_opt initial_route_only


will be insertedwill be insertedat end of at end of routing phasesrouting phases

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##Report redundant via rate per layer

report_design -physical

Automatic Redundant Via Insertion


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Automatic Redundant Via Insertion

Automatically inserts DVs at end of detail route oreco route. Hidden 2007.12-SP5-2Unhidden 2008.09-SP2Set a ter nsert ng s so t at rate rema ns

nearly constant through rest of flowWW , rou e_op wre-double the vias on routing changed nets

Extraction and timing effects are seen before and after route_opt

route_opt optimizations are based on these effects

set_route_zrt_common_options-post_detail_route_redundant_via_insertion{ off | low | medium | hi h }

481-Include define_zrt_redundant_vias , if used, inany script the automatic option may apply in

Soft Concurrent Double Via


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Soft Concurrent Double Via

Soft rules to increase DV rateReserves space for later DV to be inserted

Hidden 2007.12-SP5-2Unhidden 2008.09-SP4

set_route_zrt_common_options- concurrent_redundant_via_mode

off reserve s ace_

-concurrent_redundant_via_effort_level

{ low | medium | high }

-eco_route_concurrent_redundant_via_mode{ off | reserve_space }

-eco_route_concurrent_redundant_via_effort_level

{ low | medium | high }

Separate controls available for normal and ecorouting

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Run insert_zrt_redundant_vias later to insert

Agenda


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Agenda

ZZ



EE

Summary

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Summary


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Summary

Zroute is IC Compilers brand new, super-fast,DFM-friendly router

FF - -

Concurrent DRC, antenna rules, wire and via optimizationConcurrent redundant via insertion for higher yieldSoft rule support for lithography-friendly routingSignal-integrity-driven and timing-driven detail routingSimplified flow for ease-of-use

Zroute is available in version B-2008.09 to all

Co-exists with the classic IC Compiler router S

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S

More info: https://solvnet.synopsys.com/zroute


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Predictable Success

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Appendix


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ppe d

More Details Getting Started With ZrouteTechnology File and Parameter Translation

Script Conversion

This section provides addition details about getting startedwith Zroute for even more complete materials, see thecustomer training materials available from your Synopsys

.

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Technology File Details


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gy

All vias that you want Zroute to use (non-pinaccess) must be defined as default viasContactCode "VIA23" {

isDefaultContact = 1

}

All routing rules must be in the technology file for

Rules implemented as parametersM1FloatingParaLenForViaOffLimit

M1FloatingSpaceForViaOffLimit

Move to technology file for both classic router and Zroute=

541-

fatWireViaKeepoutMaxSpacingThreshold = S1

Default Vias and Via Regions


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g

Zroute depends on the same via regions as theclassic router to access pins

Blockage, pin, via (BPV) extraction is the same

If a particular via type needed to access pin and viare ion does not exist

Redo BPV with the contact specified as a default via

For non-pin access, Zroute uses only vias definedas defaultClassic router uses both default vias and vias that were

Ideally they would be the same set but for historicreasons in the classic router they might not be

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Z -

Translation Example: ignoreNotchDRC


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Most classic router scripts set the following option:se _rou e_op ons -same_ne _no c c ec _an _ x

When translated you see:Translated ignoreNotchDRC of droute 0 to

set_route_zrt_detail_options -ignore_drc{{same_net_metal_space false}}

By default, Zroute fixes notch and gapset_route_zrt_detail_options -ignore_drc {}

In o er wor s, e rans a on a ove an e au are e same

Therefore, no need to set this option in translated scripts

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Translation Example: runTimingMode


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Classic router is controlled by parameters that are

The translate_zrt_parameters command finds

No need to translate because timing is set by usingZroute options or route_opt

Other parameters, such as crosstalk prevention,are similar

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Parameter Translator Verification


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set_route_mode_options -zroute true

##Add specific Zroute options as needed based on translation

#set_route_zrt_detail_options

##No antenna fixing and non-timing-driven routingset_route_zrt_detail_options -antenna false

se _rou e_zr _g o a _op ons - m ng_ r ven a se -cross a _ r ven a se

set_route_zrt_track_options -timing_driven false -crosstalk_driven false

set_route_zrt_detail_options -timing_driven false

##Run Zroute

route_zrt_auto

Do not use

verify_zrt_route antenna falsereport_design physical classic router verify_route !

591-

##Independent DRC

verify_drc ;# 65nm or above, or signoff_drc (2008.09), or Hercules


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Script Changes


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You should modify classic router scripts to beZroute focused for final implementation scripts,ns ea o epen ng on parame er rans a on

Quick script conversion is good for proof-of-concept onlyCCplaces in script to enable features, or when needed for routing convergence

RRZroute options you have set

Commands mi ht be reordered, deleted, or added

due to Zroute behaviorRefer to the IC Compiler Recommended Methodology with

611-More details in subsequent sections

Common Missteps When Starting Zroute


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Using verify_route to check results

TT

Commands might have equivalence, but often notneeded since Zroute is more concurrent and simplifiedCommands used because of deficiencies in classicrouter or flow

Correct order has chan edMeasuring Router QoR

If optimize wire via is run in classic router _ _

Routing QoR is similar, but runtime is much better inZroute (~3-5x)

I

621-

I _ _ Route QoR is much improved, routing runtime should still

be faster in Zroute (~2x)

Script Changes


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You should modify classic router scripts to beZroute focused for final implementation scripts,ns ea o epen ng on parame er rans a on

Quick script conversion is good for proof-of-concept onlyCCplaces in script to enable features, or when needed for routing convergence

RRZroute options you have set

Commands mi ht be reordered, deleted, or added

due to Zroute behaviorRefer to the IC Compiler recommended methodology with

631-More details in subsequent sections

Script Conversion Tip Search and Repair


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Dont blindly convert every route_search_repair rou e_zr _ e a ncremen a rue

Often classic router needed search and repair

Antenna fixing

Off-grid pinsZroute converges faster and stops when it detectsnonconvergence

Classic router used several iterations of search andrepair, spread through scripts, to help control runtime

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Script Conversion Tip Redundant Vias


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Initially classic router could not automatically

Some customers created complex scripts to query viasfrom the databaseforeach via [get_via_masters *] {

}

Try to use Zroute default firstFinds available vias and discards nonoptimal viasRR

Use the list_only option to customizeS

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S

Script Conversion Tip Wire Spreading


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Do not use spread_zrt_wires just after initial

Some classic router scripts do thisSSslower Zroute has stronger crosstalk avoidance and timing-

Pre-spreading should not be needed and can producesuboptimal results

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Documents

Zroute Technical Tutorial v2 03 024524