feat: draw isosub over the design

Signed-off-by: Kareem Farid <kareefardi@users.noreply.github.com>

Author: kareefardi

openlane/config/pdk_compat.py

@@ -251,4 +251,7 @@ def process_sta(key: str):
     elif new["PDK"].startswith("gf180mcu"):
         new["HEURISTIC_ANTENNA_THRESHOLD"] = 130
 
+    if new["PDK"].startswith("sky130"):
+        new["ISOSUB_LAYER"] = (81, 53)
+
     return new

openlane/scripts/klayout/stream_out.py

@@ -77,6 +77,10 @@
     required=True,
     help="KLayout .map (LEF/DEF layer map) file",
 )
+@click.option(
+    "--isosub",
+    "isosub",
+)
 @click.option("-w", "--with-gds-file", "input_gds_files", multiple=True, default=[])
 @click.option("-s", "--seal-gds-file", "seal_gds", default=None)
 @click.option(
@@ -100,6 +104,7 @@ def stream_out(
     seal_gds: Optional[str],
     design_name: str,
     input: str,
+    isosub: str,
 ):  # Load technology file
     try:
         tech = pya.Technology()
@@ -165,6 +170,13 @@ def stream_out(
 
         # Write out the GDS
         print(f"[INFO] Writing out GDS '{output}'…")
+        if isosub is not None:
+            top_cell_bbox = top_only_layout.top_cell().bbox()
+            isosub_layer = top_only_layout.layer(
+                int(isosub.split(";")[0]), int(isosub.split(";")[1])
+            )
+            top_only_layout.top_cell().shapes(isosub_layer).insert(top_cell_bbox)
+            print("[INFO] Added isosub")
         top_only_layout.write(output)
         print("[INFO] Done.")
     except Exception as e:

openlane/scripts/magic/add_subcut.tcl

@@ -0,0 +1,30 @@
+# Copyright 2024 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+source $::env(SCRIPTS_DIR)/magic/common/read.tcl
+drc off
+read_pdk_gds
+gds noduplicates true
+gds read $::env(CURRENT_GDS)
+load $::env(DESIGN_NAME)
+select top cell
+paint isosub
+if {  $::env(MAGIC_DISABLE_CIF_INFO) } {
+	cif *hier write disable
+	cif *array write disable
+}
+gds nodatestamp yes
+if { $::env(MAGIC_GDS_POLYGON_SUBCELLS) } {
+	gds polygon subcells true
+}
+gds write $::env(SAVE_MAG_GDS)

openlane/scripts/magic/def/mag_gds.tcl

@@ -75,6 +75,10 @@ if { $::env(MAGIC_GDS_POLYGON_SUBCELLS) } {
 	gds polygon subcells true
 }
 
+if { $::env(MAGIC_ADD_ISOSUB) } {
+    paint isosub
+}
+
 gds write $::env(SAVE_MAG_GDS)
 puts "\[INFO\] GDS Write Complete"
 

openlane/steps/klayout.py

@@ -24,7 +24,7 @@
 from .step import ViewsUpdate, MetricsUpdate, Step, StepError, StepException
 
 from ..config import Variable
-from ..logging import info
+from ..logging import info, warn
 from ..state import DesignFormat, State
 from ..common import Path, get_script_dir, mkdirp, _get_process_limit
 
@@ -185,6 +185,21 @@ class StreamOut(KLayoutStep):
     id = "KLayout.StreamOut"
     name = "GDSII Stream Out (KLayout)"
 
+    config_vars = KLayoutStep.config_vars + [
+        Variable(
+            "ISOSUB_LAYER",
+            Optional[Tuple[int, int]],
+            "Layer/datatype pair for subcut",
+            pdk=True,
+        ),
+        Variable(
+            "KLAYOUT_ADD_ISOSUB",
+            bool,
+            default=False,
+            description="Add isosub(subcut) drawing over the design. Useful when the design is getting integarated in a design with multiple power domains",
+        ),
+    ]
+
     inputs = [DesignFormat.DEF]
     outputs = [DesignFormat.GDS, DesignFormat.KLAYOUT_GDS]
 
@@ -197,6 +212,14 @@ def run(self, state_in: State, **kwargs) -> Tuple[ViewsUpdate, MetricsUpdate]:
         )
         kwargs, env = self.extract_env(kwargs)
 
+        isosub_layer_arg = []
+        if self.config.get("KLAYOUT_ADD_ISOSUB"):
+            if isosub_layer := self.config.get("ISOSUB_LAYER"):
+                isosub_layer_arg = ["--isosub", f"{isosub_layer[0]};{isosub_layer[1]}"]
+            else:
+                warn(
+                    "KLAYOUT_ADD_ISOSUB enabled but no ISOSUB_LAYER defined for the PDK. Not going to add isosub to the design"
+                )
         self.run_pya_script(
             [
                 sys.executable,
@@ -211,7 +234,8 @@ def run(self, state_in: State, **kwargs) -> Tuple[ViewsUpdate, MetricsUpdate]:
                 "--top",
                 self.config["DESIGN_NAME"],
             ]
-            + self.get_cli_args(include_lefs=True, include_gds=True),
+            + self.get_cli_args(include_lefs=True, include_gds=True)
+            + isosub_layer_arg,
             env=env,
         )
 

openlane/steps/magic.py

@@ -274,6 +274,12 @@ class StreamOut(MagicStep):
             "A flag to move the layout such that it's origin in the lef generated by magic is 0,0.",
             default=False,
         ),
+        Variable(
+            "MAGIC_ADD_ISOSUB",
+            bool,
+            "Add isosub(subcut) drawing over the design. Useful when the design is getting integarated in a design with multiple power domains",
+            default=False,
+        ),
         Variable(
             "MAGIC_DISABLE_CIF_INFO",
             bool,
@@ -564,3 +570,15 @@ def run(self, state_in: State, **kwargs) -> Tuple[ViewsUpdate, MetricsUpdate]:
             magic.send_signal(SIGKILL)
 
         return {}, {}
+
+
+@Step.factory.register()
+class AddIsosub(MagicStep):
+    id = "Magic.AddIsosub"
+    name = "Add isosub(subcut) to the design"
+
+    outputs = [DesignFormat.GDS, DesignFormat.MAG_GDS]
+    config_vars = StreamOut.config_vars
+
+    def get_script_path(self):
+        return os.path.join(get_script_dir(), "magic", "add_subcut.tcl")