lvs: three defects that made gf180 report the wrong answer

src/glayout/cells/composite/differential_to_single_ended_converter/differential_to_single_ended_converter.py

@@ -196,22 +196,29 @@ def differential_to_single_ended_converter_netlist(pdk: MappedPDK, half_pload: t
     return Netlist(
         circuit_name="DIFF_TO_SINGLE",
         nodes=['VIN', 'VOUT', 'VSS', 'VSS2'],
-        source_netlist=""".subckt {circuit_name} {nodes} """ + f'l={half_pload[1]} w={half_pload[0]} mt={4*2} mb={2 * half_pload[2]} ' + """
-XTOP1 VOUT VIN VSS  VSS {model} l={{l}} w={{w}} m={{mt}}
-XTOP2 VSS2 VIN VSS  VSS {model} l={{l}} w={{w}} m={{mt}}
-XBOT1 VIN  VIN VOUT VSS {model} l={{l}} w={{w}} m={{mb}}
-XBOT2 VOUT VIN VSS2 VSS {model} l={{l}} w={{w}} m={{mb}}
-XDUMMY1  VSS VSS VSS VSS {model} l={{l}} w={{w}}
-XDUMMY2  VSS VSS VSS VSS {model} l={{l}} w={{w}}
-XDUMMY3  VSS VSS VSS VSS {model} l={{l}} w={{w}}
-XDUMMY4  VSS VSS VSS VSS {model} l={{l}} w={{w}}
-XDUMMY5  VSS VSS VSS VSS {model} l={{l}} w={{w}}
-XDUMMY6  VSS VSS VSS VSS {model} l={{l}} w={{w}}
-XDUMMY7  VSS VSS VSS VSS {model} l={{l}} w={{w}}
-XDUMMY8  VSS VSS VSS VSS {model} l={{l}} w={{w}}
-XDUMMY9  VSS VSS VSS VSS {model} l={{l}} w={{w}}
-XDUMMY10 VSS VSS VSS VSS {model} l={{l}} w={{w}}
-.ends {circuit_name}""",
+        # No parameters on the top-level .subckt line. KLayout's SPICE reader folds a
+        # subcircuit's defaults into its NAME -- `l=1.0 w=3.0 mt=8 mb=4` made this
+        # circuit `DIFF_TO_SINGLE(L=1.0,MT=8,MB=4,W=3.0)` -- so the gf180 deck could
+        # not match it to the layout's top cell and aborted with "Can't find a
+        # schematic counterpart for the top cell", which the runner reported as the
+        # catch-all "LVS inconclusive". Unlike two_transistor_interdigitized the body
+        # here referenced {l}/{w}/{mt}/{mb}, so those are inlined below.
+        source_netlist=""".subckt {circuit_name} {nodes}""" + f"""
+XTOP1 VOUT VIN VSS  VSS {{model}} l={half_pload[1]} w={half_pload[0]} m={4*2}
+XTOP2 VSS2 VIN VSS  VSS {{model}} l={half_pload[1]} w={half_pload[0]} m={4*2}
+XBOT1 VIN  VIN VOUT VSS {{model}} l={half_pload[1]} w={half_pload[0]} m={2*half_pload[2]}
+XBOT2 VOUT VIN VSS2 VSS {{model}} l={half_pload[1]} w={half_pload[0]} m={2*half_pload[2]}
+XDUMMY1   VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+XDUMMY2   VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+XDUMMY3   VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+XDUMMY4   VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+XDUMMY5   VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+XDUMMY6   VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+XDUMMY7   VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+XDUMMY8   VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+XDUMMY9   VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+XDUMMY10  VSS VSS VSS VSS {{model}} l={half_pload[1]} w={half_pload[0]}
+.ends {{circuit_name}}""",
         instance_format="X{name} {nodes} {circuit_name} l={length} w={width} mt={mult_top} mb={mult_bot}",
         parameters={
             'model': pdk.models['pfet'],

src/glayout/placement/two_transistor_interdigitized.py

@@ -93,7 +93,14 @@ def two_tran_interdigitized_netlist(
     # X-prefix is sky130's magic+netgen tech expectation; klayout decks
     # that classify primitive MOSFETs by SPICE prefix get their netlist
     # X→M-rewritten by the LVS runner.
-    source_netlist = """.subckt {circuit_name} {nodes} """ + f'l={length} w={width} m={1} '+ f"""
+    # No parameters on the top-level .subckt line. KLayout's SPICE reader folds a
+    # subcircuit's default parameters into its *name* -- `l=0.28u w=3u m=1` turns the
+    # circuit into `TWO_TRANSISTOR_INTERDIGITIZED(L=0.28U,M=1,W=3U)` -- so the gf180
+    # klayout deck can no longer match it to the layout's top cell and aborts with
+    # "Can't find a schematic counterpart for the top cell". The device lines below
+    # carry l/w/m explicitly, so these defaults were never used. sky130 is unaffected
+    # (magic+netgen), which is why this only ever showed up on gf180.
+    source_netlist = """.subckt {circuit_name} {nodes}""" + f"""
 XA VDD1 VG1 VSS1 VB {model} l={length} w={width} m={mtop}
 XB VDD2 VG2 VSS2 VB {model} l={length} w={width} m={mtop}"""
     if with_dummy:

tests/lvs/klayout_gf180.py

@@ -301,7 +301,12 @@ def run_lvs_klayout_gf180(
     FuseTop / met3) or "B" (met4 / FuseTop / met5). The two are mutually
     exclusive at process level, so the wrong one extracts no capacitor at all
     and every MIM shows up as missing from the layout. Defaults to
-    ``$GF180_MIM_OPTION``, then to "A".
+    ``$GF180_MIM_OPTION``, then to "B" -- which is what glayout actually builds:
+    both ``mimcap`` and ``mimcap_array`` default to ``option="B"``
+    (primitives/mimcap.py). This used to default to "A", so every gf180 cell with
+    a MIM extracted zero capacitors and LVS reported "N schematic device(s)
+    missing from layout [CAP_MIM_2F0FF]". Set $GF180_MIM_OPTION=A for a layout
+    genuinely built on the met2/met3 stack.
     """
     layout_path = Path(layout)
     netlist_path = Path(netlist)
@@ -310,7 +315,7 @@ def run_lvs_klayout_gf180(
     rpt_dir.mkdir(parents=True, exist_ok=True)
 
     pdk_root = pdk_root or os.environ.get("PDK_ROOT", "/foss/pdks")
-    mim_option = (mim_option or os.environ.get("GF180_MIM_OPTION") or "A").upper()
+    mim_option = (mim_option or os.environ.get("GF180_MIM_OPTION") or "B").upper()
     if mim_option not in ("A", "B"):
         raise ValueError(f"mim_option must be 'A' or 'B', got {mim_option!r}")
     deck_dir = _resolve_deck_dir(pdk_root)

tests/lvs/run_cell_lvs.py

@@ -227,8 +227,9 @@ def main() -> int:
             "gf180 MIM stack the deck should extract: A (met2/FuseTop/met3) "
             "or B (met4/FuseTop/met5). They are mutually exclusive at process "
             "level, so picking the wrong one extracts no capacitor and every "
-            "MIM reports as missing from the layout. Default: $GF180_MIM_OPTION, "
-            "else A."
+            "MIM reports as missing from the layout. glayout builds option B "
+            "(mimcap/mimcap_array default to option=\"B\"), so that is the "
+            "default here too. Default: $GF180_MIM_OPTION, else B."
         ),
     )
     parser.add_argument(

tests/run_ci_locally.py

@@ -52,10 +52,12 @@
 uv python install 3.10 >/dev/null 2>&1
 PYTHON310="$(uv python find 3.10)"
 
-if [ ! -x /work/.drc-cache/venv/bin/python ]; then
+if [ ! -f /work/.drc-cache/venv/.installed ]; then
+    rm -rf /work/.drc-cache/venv
     "$PYTHON310" -m venv /work/.drc-cache/venv
     . /work/.drc-cache/venv/bin/activate
-    uv pip install -e . >/dev/null
+    uv pip install -e .
+    touch /work/.drc-cache/venv/.installed
 else
     # Cache hit: glayout's .pth points to /work which is the same on every
     # run, so no refresh is needed (matches the workflows).