maliberty · Nov 6, 2026 · Nov 3, 2026 · Nov 3, 2026 · Nov 3, 2026 · Nov 5, 2026
diff --git a/docs/user/FlowVariables.md b/docs/user/FlowVariables.md
@@ -158,6 +158,7 @@ configuration file.
 | <a name="GDS_ALLOW_EMPTY"></a>GDS_ALLOW_EMPTY| Single regular expression of module names of macros that have no .gds file| |
 | <a name="GDS_FILES"></a>GDS_FILES| Path to platform GDS files.| |
 | <a name="GENERATE_ARTIFACTS_ON_FAILURE"></a>GENERATE_ARTIFACTS_ON_FAILURE| For instance Bazel needs artifacts (.odb and .rpt files) on a failure to allow the user to save hours on re-running the failed step locally, but when working with a Makefile flow, it is more natural to fail the step and leave the user to manually inspect the logs and artifacts directly via the file system. Set to 1 to change the behavior to generate artifacts upon failure to e.g. do a global route. The exit code will still be non-zero on all other failures that aren't covered by the "useful to inspect the artifacts on failure" use-case. Example: just like detailed routing, a global route that fails with congestion, is not a build failure(as in exit code non-zero), it is a successful(as in zero exit code) global route that produce reports detailing the problem. Detailed route will not proceed, if there is global routing congestion This allows build systems, such as bazel, to create artifacts for global and detailed route, even if the operation had problems, without having know about the semantics between global and detailed route. Considering that global and detailed route can run for a long time and use a lot of memory, this allows inspecting results on a laptop for a build that ran on a server.| 0|
+| <a name="GLOBAL_CONNECT_TCL"></a>GLOBAL_CONNECT_TCL| File path to the add_global_connection rules that connect the supply pins of the instances to the supply nets. Sourced at floorplan right after the netlist is loaded, before any step can mark an instance dont_touch; the rules are kept in the database. The platform's file by default; a design whose PDN_TCL names other supply nets sets its own. PDN_TCL defines the grids.| |
 | <a name="GLOBAL_PLACEMENT_ARGS"></a>GLOBAL_PLACEMENT_ARGS| Use additional tuning parameters during global placement other than default args defined in global_place.tcl.| |
 | <a name="GLOBAL_ROUTE_ARGS"></a>GLOBAL_ROUTE_ARGS| Replaces default arguments for global route. The -congestion_iterations default is set by the flow (30 for FastRoute, 10 for CUGR); add -congestion_iterations here to override it.| -congestion_report_iter_step 5 -verbose|
 | <a name="GLOBAL_ROUTE_USE_CUGR"></a>GLOBAL_ROUTE_USE_CUGR| Passed as -use_cugr to global_route. Uses CUGR as the global routing solver instead of the default FastRoute solver. NOTE: CUGR is not ready for production.| 0|
@@ -420,6 +421,7 @@ configuration file.
 - [FLOORPLAN_DEF](#FLOORPLAN_DEF)
 - [FOOTPRINT](#FOOTPRINT)
 - [FOOTPRINT_TCL](#FOOTPRINT_TCL)
+- [GLOBAL_CONNECT_TCL](#GLOBAL_CONNECT_TCL)
 - [HOLD_SLACK_MARGIN](#HOLD_SLACK_MARGIN)
 - [IO_CONSTRAINTS](#IO_CONSTRAINTS)
 - [MACRO_PLACEMENT_TCL](#MACRO_PLACEMENT_TCL)

diff --git a/flow/designs/gf180/uart-blocks/BLOCKS_grid_strategy.tcl b/flow/designs/gf180/uart-blocks/BLOCKS_grid_strategy.tcl
@@ -1,17 +1,4 @@
 ####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDP$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDC$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VNW$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSC$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VPW$}
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}

diff --git a/flow/designs/gf180/uart-blocks/uart_rx/pdn.tcl b/flow/designs/gf180/uart-blocks/uart_rx/pdn.tcl
@@ -1,17 +1,4 @@
 ####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDP$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDC$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VNW$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSC$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VPW$}
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}

diff --git a/flow/designs/ihp-sg13g2/i2c-gpio-expander/I2cDeviceCtrl/config.mk b/flow/designs/ihp-sg13g2/i2c-gpio-expander/I2cDeviceCtrl/config.mk
@@ -17,5 +17,6 @@ export PLACE_DENSITY = 0.75
 
 export CORNERS = slow typ fast
 
+export GLOBAL_CONNECT_TCL = $(DESIGN_HOME)/$(PLATFORM)/i2c-gpio-expander/global_connect.tcl
 export PDN_TCL = $(DESIGN_HOME)/$(PLATFORM)/$(TOP_DESIGN_NICKNAME)/${DESIGN_NAME}/pdn.tcl
 
diff --git a/flow/designs/ihp-sg13g2/i2c-gpio-expander/I2cDeviceCtrl/pdn.tcl b/flow/designs/ihp-sg13g2/i2c-gpio-expander/I2cDeviceCtrl/pdn.tcl
@@ -1,18 +1,3 @@
-# standard cells
-add_global_connection -net {VDD} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -pin_pattern {^VDDCE$}
-add_global_connection -net {VSS} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -pin_pattern {^VSSE$}
-
-# macros
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {VDD!} -power
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {VSS!} -ground
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-
-global_connect
-
 # core voltage domain
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}
 

diff --git a/flow/designs/ihp-sg13g2/i2c-gpio-expander/config.mk b/flow/designs/ihp-sg13g2/i2c-gpio-expander/config.mk
@@ -51,6 +51,7 @@ export FOOTPRINT_TCL = $(PLATFORM_DIR)/pad.tcl
 
 export MACRO_PLACEMENT_TCL = $(DESIGN_HOME)/$(PLATFORM)/$(DESIGN_NICKNAME)/macros.tcl
 
+export GLOBAL_CONNECT_TCL = $(DESIGN_HOME)/$(PLATFORM)/i2c-gpio-expander/global_connect.tcl
 export PDN_TCL = $(DESIGN_HOME)/$(PLATFORM)/$(DESIGN_NICKNAME)/pdn.tcl
 
 export BLOCKS = I2cDeviceCtrl

diff --git a/flow/designs/ihp-sg13g2/i2c-gpio-expander/global_connect.tcl b/flow/designs/ihp-sg13g2/i2c-gpio-expander/global_connect.tcl
@@ -0,0 +1,14 @@
+# Global connections, made at floorplan right after the netlist is
+# loaded (GLOBAL_CONNECT_TCL); the PDN scripts define the grids.
+# standard cells
+add_global_connection -net {VDD} -pin_pattern {^VDD$} -power
+add_global_connection -net {VDD} -pin_pattern {^VDDPE$}
+add_global_connection -net {VDD} -pin_pattern {^VDDCE$}
+add_global_connection -net {VSS} -pin_pattern {^VSS$} -ground
+add_global_connection -net {VSS} -pin_pattern {^VSSE$}
+
+# macros
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {VDD!} -power
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {VSS!} -ground
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
diff --git a/flow/designs/ihp-sg13g2/i2c-gpio-expander/pdn.tcl b/flow/designs/ihp-sg13g2/i2c-gpio-expander/pdn.tcl
@@ -1,18 +1,3 @@
-# standard cells
-add_global_connection -net {VDD} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -pin_pattern {^VDDCE$}
-add_global_connection -net {VSS} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -pin_pattern {^VSSE$}
-
-# macros
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {VDD!} -power
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {VSS!} -ground
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-
-global_connect
-
 # core voltage domain
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}
 

diff --git a/flow/designs/nangate45/gcd/grid_strategy-M1-M4-M7.tcl b/flow/designs/nangate45/gcd/grid_strategy-M1-M4-M7.tcl
@@ -1,13 +1,4 @@
 ####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
-global_connect
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}

diff --git a/flow/platforms/asap7/config.mk b/flow/platforms/asap7/config.mk
@@ -37,6 +37,8 @@ export PLACE_SITE              ?= asap7sc7p5t
 export MAKE_TRACKS             = $(PLATFORM_DIR)/openRoad/make_tracks.tcl
 
 # Define default PDN config
+export GLOBAL_CONNECT_TCL ?= $(PLATFORM_DIR)/openRoad/pdn/global_connect.tcl
+
 ifeq ($(BLOCKS),)
    export PDN_TCL ?= $(PLATFORM_DIR)/openRoad/pdn/grid_strategy-M1-M2-M5-M6.tcl
 else

diff --git a/flow/platforms/asap7/openRoad/pdn/BLOCKS_grid_strategy.tcl b/flow/platforms/asap7/openRoad/pdn/BLOCKS_grid_strategy.tcl
@@ -1,12 +1,6 @@
 # Top level PDN for macros using BLOCK_grid_strategy.tcl
 source $::env(SCRIPTS_DIR)/util.tcl
 
-####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-
 ####################################
 # voltage domains
 ####################################

diff --git a/flow/platforms/asap7/openRoad/pdn/BLOCK_grid_strategy.tcl b/flow/platforms/asap7/openRoad/pdn/BLOCK_grid_strategy.tcl
@@ -1,11 +1,5 @@
 # macro level counterpart to BLOCKS_grid_strategy.tcl
 
-####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-
 ####################################
 # voltage domains
 ####################################

diff --git a/flow/platforms/asap7/openRoad/pdn/global_connect.tcl b/flow/platforms/asap7/openRoad/pdn/global_connect.tcl
@@ -0,0 +1,7 @@
+# Global connections, made at floorplan right after the netlist is
+# loaded (GLOBAL_CONNECT_TCL); the PDN scripts define the grids.
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
diff --git a/flow/platforms/asap7/openRoad/pdn/grid_strategy-M1-M2-M5-M6.tcl b/flow/platforms/asap7/openRoad/pdn/grid_strategy-M1-M2-M5-M6.tcl
@@ -1,13 +1,4 @@
 ####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
-global_connect
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}

diff --git a/flow/platforms/gf180/config.mk b/flow/platforms/gf180/config.mk
@@ -76,6 +76,7 @@ export IO_PLACER_H                           ?= Metal3
 export IO_PLACER_V                           ?= Metal4
 
 # Define default PDN config
+export GLOBAL_CONNECT_TCL ?= $(PLATFORM_DIR)/openROAD/pdn/global_connect.tcl
 export PDN_TCL                               ?= $(PLATFORM_DIR)/openROAD/pdn/pdn_grid_strategy_$(TRACK_OPTION)_6M.cfg
 
 # Endcap and Welltie cells

diff --git a/flow/platforms/gf180/openROAD/pdn/global_connect.tcl b/flow/platforms/gf180/openROAD/pdn/global_connect.tcl
@@ -0,0 +1,12 @@
+# Global connections, made at floorplan right after the netlist is
+# loaded (GLOBAL_CONNECT_TCL); the PDN scripts define the grids.
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDP$}
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDC$}
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VNW$}
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSC$}
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VPW$}
diff --git a/flow/platforms/gf180/openROAD/pdn/pdn_grid_strategy_7t_6M.cfg b/flow/platforms/gf180/openROAD/pdn/pdn_grid_strategy_7t_6M.cfg
@@ -1,17 +1,4 @@
 ####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDP$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDC$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VNW$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSC$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VPW$}
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}

diff --git a/flow/platforms/gf180/openROAD/pdn/pdn_grid_strategy_9t_6M.cfg b/flow/platforms/gf180/openROAD/pdn/pdn_grid_strategy_9t_6M.cfg
@@ -1,17 +1,4 @@
 ####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDP$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDC$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VNW$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSC$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VPW$}
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}

diff --git a/flow/platforms/gt2n/config.mk b/flow/platforms/gt2n/config.mk
@@ -98,6 +98,7 @@ export IO_PLACER_H ?= M2
 export IO_PLACER_V ?= M3
 
 # Define default PDN config
+export GLOBAL_CONNECT_TCL ?= $(PLATFORM_DIR)/global_connect.tcl
 export PDN_TCL ?= $(PLATFORM_DIR)/pdn.tcl
 
 # Endcap and Welltie cells

diff --git a/flow/platforms/gt2n/global_connect.tcl b/flow/platforms/gt2n/global_connect.tcl
@@ -0,0 +1,4 @@
+# Global connections, made at floorplan right after the netlist is
+# loaded (GLOBAL_CONNECT_TCL); the PDN scripts define the grids.
+add_global_connection -net {vdd} -inst_pattern {.*} -pin_pattern {^vdd$} -power
+add_global_connection -net {vss} -inst_pattern {.*} -pin_pattern {^vss$} -ground
diff --git a/flow/platforms/gt2n/pdn.tcl b/flow/platforms/gt2n/pdn.tcl
@@ -1,10 +1,4 @@
 ####################################
-# global connections
-####################################
-add_global_connection -net {vdd} -inst_pattern {.*} -pin_pattern {^vdd$} -power
-add_global_connection -net {vss} -inst_pattern {.*} -pin_pattern {^vss$} -ground
-global_connect
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {vdd} -ground {vss}

diff --git a/flow/platforms/ihp-sg13g2/config.mk b/flow/platforms/ihp-sg13g2/config.mk
@@ -86,6 +86,7 @@ export IO_PLACER_V ?= Metal2
 export IO_PLACER_H ?= Metal3
 
 # Define default PDN config
+export GLOBAL_CONNECT_TCL ?= $(PLATFORM_DIR)/global_connect.tcl
 export PDN_TCL ?= $(PLATFORM_DIR)/pdn.tcl
 
 # To allow the core rings to fit inside the core area

diff --git a/flow/platforms/ihp-sg13g2/global_connect.tcl b/flow/platforms/ihp-sg13g2/global_connect.tcl
@@ -0,0 +1,7 @@
+# Global connections, made at floorplan right after the netlist is
+# loaded (GLOBAL_CONNECT_TCL); the PDN scripts define the grids.
+add_global_connection -net {VDD} -pin_pattern {^VDD$} -power
+add_global_connection -net {VDD} -pin_pattern {^VDDPE$}
+add_global_connection -net {VDD} -pin_pattern {^VDDCE$}
+add_global_connection -net {VSS} -pin_pattern {^VSS$} -ground
+add_global_connection -net {VSS} -pin_pattern {^VSSE$}
diff --git a/flow/platforms/ihp-sg13g2/pdn.tcl b/flow/platforms/ihp-sg13g2/pdn.tcl
@@ -1,14 +1,4 @@
 ####################################
-# global connections
-####################################
-# standard cells
-add_global_connection -net {VDD} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -pin_pattern {^VDDCE$}
-add_global_connection -net {VSS} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -pin_pattern {^VSSE$}
-global_connect
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}

diff --git a/flow/platforms/nangate45/config.mk b/flow/platforms/nangate45/config.mk
@@ -54,6 +54,7 @@ export IO_PLACER_H ?= metal5
 export IO_PLACER_V ?= metal6
 
 # Define default PDN config
+export GLOBAL_CONNECT_TCL ?= $(PLATFORM_DIR)/global_connect.tcl
 export PDN_TCL ?= $(PLATFORM_DIR)/grid_strategy-M1-M4-M7.tcl
 
 # Endcap and Welltie cells

diff --git a/flow/platforms/nangate45/global_connect.tcl b/flow/platforms/nangate45/global_connect.tcl
@@ -0,0 +1,7 @@
+# Global connections, made at floorplan right after the netlist is
+# loaded (GLOBAL_CONNECT_TCL); the PDN scripts define the grids.
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
diff --git a/flow/platforms/nangate45/grid_strategy-M1-M4-M7.tcl b/flow/platforms/nangate45/grid_strategy-M1-M4-M7.tcl
@@ -1,13 +1,4 @@
 ####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
-global_connect
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}

diff --git a/flow/platforms/sky130hd/config.mk b/flow/platforms/sky130hd/config.mk
@@ -97,6 +97,7 @@ export IO_PLACER_H ?= met3
 export IO_PLACER_V ?= met2
 
 # Define default PDN config
+export GLOBAL_CONNECT_TCL ?= $(PLATFORM_DIR)/global_connect.tcl
 export PDN_TCL ?= $(PLATFORM_DIR)/pdn.tcl
 
 # Endcap and Welltie cells

diff --git a/flow/platforms/sky130hd/global_connect.tcl b/flow/platforms/sky130hd/global_connect.tcl
@@ -0,0 +1,11 @@
+# Global connections, made at floorplan right after the netlist is
+# loaded (GLOBAL_CONNECT_TCL); the PDN scripts define the grids.
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {VPWR}
+add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {VPB}
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {VGND}
+add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {VNB}
diff --git a/flow/platforms/sky130hd/pdn.tcl b/flow/platforms/sky130hd/pdn.tcl
@@ -1,17 +1,4 @@
 ####################################
-# global connections
-####################################
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDD$} -power
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDPE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {^VDDCE$}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {VPWR}
-add_global_connection -net {VDD} -inst_pattern {.*} -pin_pattern {VPB}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSS$} -ground
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {^VSSE$}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {VGND}
-add_global_connection -net {VSS} -inst_pattern {.*} -pin_pattern {VNB}
-global_connect
-####################################
 # voltage domains
 ####################################
 set_voltage_domain -name {CORE} -power {VDD} -ground {VSS}
Original file line number	Diff line number	Diff line change
Expand Up		@@ -17,5 +17,6 @@ export PLACE_DENSITY = 0.75

		export CORNERS = slow typ fast

		export GLOBAL_CONNECT_TCL = $(DESIGN_HOME)/$(PLATFORM)/i2c-gpio-expander/global_connect.tcl
		export PDN_TCL = $(DESIGN_HOME)/$(PLATFORM)/$(TOP_DESIGN_NICKNAME)/${DESIGN_NAME}/pdn.tcl