Merge pull request #3657 from chrisgelinek-rl/add-var-BUFFER_PORTS_ARGS

Add var BUFFER_PORTS_ARGS

Author: maliberty

docs/user/FlowVariables.md

@@ -102,6 +102,7 @@ configuration file.
 | <a name="ADDITIONAL_LIBS"></a>ADDITIONAL_LIBS| Hardened macro library files listed here. The library information is immutable and used throughout all stages. Not stored in the .odb file.| |
 | <a name="BALANCE_ROWS"></a>BALANCE_ROWS| Balance rows during placement.| 0|
 | <a name="BLOCKS"></a>BLOCKS| Blocks used as hard macros in a hierarchical flow. Do note that you have to specify block-specific inputs file in the directory mentioned by Makefile.| |
+| <a name="BUFFER_PORTS_ARGS"></a>BUFFER_PORTS_ARGS| Specify arguments to the buffer_ports call during placement. Only used if DONT_BUFFER_PORTS=0.| |
 | <a name="CAP_MARGIN"></a>CAP_MARGIN| Specifies a capacitance margin when fixing max capacitance violations. This option allows you to overfix.| |
 | <a name="CDL_FILES"></a>CDL_FILES| Insert additional Circuit Description Language (`.cdl`) netlist files.| |
 | <a name="CELL_PAD_IN_SITES_DETAIL_PLACEMENT"></a>CELL_PAD_IN_SITES_DETAIL_PLACEMENT| Cell padding on both sides in site widths to ease routability in detail placement.| 0|
@@ -369,6 +370,7 @@ configuration file.
 ## place variables
 
 - [BALANCE_ROWS](#BALANCE_ROWS)
+- [BUFFER_PORTS_ARGS](#BUFFER_PORTS_ARGS)
 - [CELL_PAD_IN_SITES_DETAIL_PLACEMENT](#CELL_PAD_IN_SITES_DETAIL_PLACEMENT)
 - [CELL_PAD_IN_SITES_GLOBAL_PLACEMENT](#CELL_PAD_IN_SITES_GLOBAL_PLACEMENT)
 - [CLUSTER_FLOPS](#CLUSTER_FLOPS)

flow/scripts/floorplan_to_place.tcl

@@ -240,7 +240,7 @@ if { $::env(GPL_TIMING_DRIVEN) } {
 if { ![env_var_exists_and_non_empty FOOTPRINT] } {
   if { ![env_var_equals DONT_BUFFER_PORTS 1] } {
     puts "Perform port buffering..."
-    buffer_ports
+    buffer_ports {*}[env_var_or_empty BUFFER_PORTS_ARGS]
   }
 }
 

flow/scripts/global_place.tcl

@@ -16,7 +16,7 @@ if { $::env(GPL_TIMING_DRIVEN) } {
 if { ![env_var_exists_and_non_empty FOOTPRINT] } {
   if { !$::env(DONT_BUFFER_PORTS) } {
     puts "Perform port buffering..."
-    buffer_ports
+    buffer_ports {*}[env_var_or_empty BUFFER_PORTS_ARGS]
   }
 }
 

flow/scripts/variables.yaml

@@ -397,6 +397,11 @@ DONT_BUFFER_PORTS:
   stages:
     - place
   default: 0
+BUFFER_PORTS_ARGS:
+  description: >
+    Specify arguments to the buffer_ports call during placement. Only used if DONT_BUFFER_PORTS=0.
+  stages:
+    - place
 REMOVE_ABC_BUFFERS:
   description: >
     Remove abc buffers from the netlist. If timing repair in floorplanning is