Update OpenROAD again + docs

nix/openroad.nix

@@ -43,12 +43,11 @@
   flex,
   bison,
   clang-tools_14,
-  ioplace-parser,
   buildEnv,
   makeBinaryWrapper,
   buildPythonEnvForInterpreter,
-  rev ? "49a497abf0011b2631ce7caab8b78bd1f9d67662",
-  sha256 ? "sha256-3o+iT+9X8/EIf4c/+FLp6GRxPGmM5kWMwK7beyICRL0=",
+  rev ? "6b5937db431d2fa1023d3865f21ccd9b65781492",
+  sha256 ? "sha256-rpv3WkOahFFkW4g+8tRiPBfBFcLwJIqK/hTgWv2tkow=",
 }: let self = clangStdenv.mkDerivation (finalAttrs: {
     name = "openroad";
     inherit rev;
@@ -65,7 +64,6 @@
       "-DTCL_HEADER=${tcl}/include/tcl.h"
       "-DUSE_SYSTEM_BOOST:BOOL=ON"
       "-DENABLE_TESTS:BOOL=OFF"
-      "-DVERBOSE=1"
     ];
 
     cmakeFlags =

openlane/steps/openroad.py

@@ -1071,7 +1071,7 @@ def run(self, state_in: State, **kwargs) -> Tuple[ViewsUpdate, MetricsUpdate]:
 @Step.factory.register()
 class TapEndcapInsertion(OpenROADStep):
     """
-    Places well TAP cells across a floorplan, as well as end-cap cells at the
+    Places welltap cells across a floorplan, as well as endcap cells at the
     edges of the floorplan.
     """
 
@@ -1103,6 +1103,13 @@ def get_script_path(self):
 
 @Step.factory.register()
 class UnplaceAll(OpenROADStep):
+    """
+    Sets placement status of *all* instances to NONE.
+
+    Useful in flows where a preliminary placement is needed as a pre-requisite
+    to something else but that placement must be discarded.
+    """
+
     id = "OpenROAD.UnplaceAll"
     name = "Unplace All"
 
@@ -1333,6 +1340,20 @@ def run(self, state_in: State, **kwargs) -> Tuple[ViewsUpdate, MetricsUpdate]:
 
 @Step.factory.register()
 class HierarchicalMacroPlacer(OpenROADStep):
+    """
+    Uses the *Hier-RTLMP* automatic macro placer in OpenROAD to place any
+    unplaced macros.
+
+    This placer is aimed at complex top-level IP integrations where hierarchy
+    information from the register-transfer level could be leveraged.
+
+    This requires the netlist to keep hierarchy information. OpenLane 2's
+    Classic flow does not do so by default, see ``Yosys.Synthesis``'s
+    documentation on how to alter that.
+
+    See this paper for more info: https://arxiv.org/pdf/2304.11761
+    """
+
     id = "OpenROAD.HierarchicalMacroPlacer"
     name = "Hierarchical Macro Placement"