Merge pull request #2551 from AcKoucher/sizing-honor-cell-footprint

add flag to enforce cell footprint honoring in all sizing operations

Author: maliberty

flow/Makefile

@@ -210,6 +210,9 @@ export CELL_PAD_IN_SITES_DETAIL_PLACEMENT ?= 0
 export ENABLE_DPO ?= 1
 export DPO_MAX_DISPLACEMENT ?= 5 1
 
+# Settings for Sizing
+export MATCH_CELL_FOOTPRINT ?= 0
+
 # Setup working directories
 export DESIGN_NICKNAME ?= $(DESIGN_NAME)
 

flow/scripts/floorplan.tcl

@@ -113,8 +113,8 @@ if { [env_var_equals REMOVE_ABC_BUFFERS 1] } {
 
 ##### Restructure for timing #########
 if { [env_var_equals RESYNTH_TIMING_RECOVER 1] } {
-  repair_design
-  repair_timing
+  repair_design_helper
+  repair_timing_helper
   # pre restructure area/timing report (ideal clocks)
   puts "Post synth-opt area"
   report_design_area
@@ -133,8 +133,8 @@ if { [env_var_equals RESYNTH_TIMING_RECOVER 1] } {
 
   # post restructure area/timing report (ideal clocks)
   remove_buffers
-  repair_design
-  repair_timing
+  repair_design_helper
+  repair_timing_helper
 
   puts "Post restructure-opt wns"
   report_worst_slack -max -digits 3

flow/scripts/global_route.tcl

@@ -51,8 +51,7 @@ proc global_route_helper {} {
     }
 
     # Repair design using global route parasitics
-    puts "Perform buffer insertion..."
-    repair_design
+    repair_design_helper
     if { $::env(DETAILED_METRICS) } {
       report_metrics 5 "global route post repair design"
     }

flow/scripts/resize.tcl

@@ -21,18 +21,7 @@ if { ![env_var_exists_and_non_empty FOOTPRINT] } {
   }
 }
 
-puts "Perform buffer insertion..."
-set additional_args ""
-if { [env_var_exists_and_non_empty CAP_MARGIN] && $::env(CAP_MARGIN) > 0.0} {
-  puts "Cap margin $::env(CAP_MARGIN)"
-  append additional_args " -cap_margin $::env(CAP_MARGIN)"
-}
-if { [env_var_exists_and_non_empty SLEW_MARGIN] && $::env(SLEW_MARGIN) > 0.0} {
-  puts "Slew margin $::env(SLEW_MARGIN)"
-  append additional_args " -slew_margin $::env(SLEW_MARGIN)"
-}
-
-repair_design {*}$additional_args
+repair_design_helper
 
 if { [env_var_exists_and_non_empty TIE_SEPARATION] } {
   set tie_separation $env(TIE_SEPARATION)

flow/scripts/util.tcl

@@ -27,10 +27,23 @@ proc repair_timing_helper { {hold_margin 1} } {
   append_env_var additional_args SKIP_GATE_CLONING -skip_gate_cloning 0
   append_env_var additional_args SKIP_BUFFER_REMOVAL -skip_buffer_removal 0
   append_env_var additional_args SKIP_LAST_GASP -skip_last_gasp 0
+  append_env_var additional_args MATCH_CELL_FOOTPRINT -match_cell_footprint 0
   puts "repair_timing [join $additional_args " "]"
   repair_timing {*}$additional_args
 }
 
+proc repair_design_helper {} {
+  puts "Perform buffer insertion and gate resizing..."
+
+  set additional_args ""
+  append_env_var additional_args CAP_MARGIN -cap_margin 1
+  append_env_var additional_args SLEW_MARGIN -slew_margin 1
+  append_env_var additional_args MATCH_CELL_FOOTPRINT -match_cell_footprint 0
+  puts "repair_design [join $additional_args " "]"
+
+  repair_design {*}$additional_args
+}
+
 proc recover_power {} {
   if { $::env(RECOVER_POWER) == 0 } {
     return
@@ -40,7 +53,10 @@ proc recover_power {} {
   report_tns
   report_wns
   report_power
-  repair_timing -recover_power $::env(RECOVER_POWER)
+  set additional_args ""
+  append_env_var additional_args RECOVER_POWER -recover_power 1
+  append_env_var additional_args MATCH_CELL_FOOTPRINT -match_cell_footprint 0
+  repair_timing {*}$additional_args
   report_tns
   report_wns
   report_power

flow/scripts/variables.yaml

@@ -622,3 +622,11 @@ GLOBAL_ROUTE_ARGS:
   stages:
     - grt
   default: -congestion_iterations 30 -congestion_report_iter_step 5 -verbose
+MATCH_CELL_FOOTPRINT:
+  description: >
+    Enforce sizing operations to only swap cells that have the same layout boundary.
+  stages:
+    - floorplan
+    - place
+    - cts
+    - route