netlist: Add PseudoCell API

When implementing concepts such as partition pins or deliberately split
nets, there's a need for something that looks like a cell (starts/ends
routing with pins on nets, has timing data) but isn't mapped to a fixed
bel in the architecture, but instead can have pin mappings defined at
runtime.

The PseudoCell allows this by providing an alternate, virtual-function
based API for such cells. When a cell has `pseudo_cell` used, instead of
calling functions such as getBelPinWire, getBelLocation or getCellDelay
in the Arch API; such data is provided by the cell itself, fully
flexible at runtime regardless of arch, via methods on the PseudoCell
implementation.

1 files changed, 24 insertions, 0 deletions

diff --git a/common/kernel/basectx.cc b/common/kernel/basectx.cc
index 83a2deea..82cdd835 100644
--- a/common/kernel/basectx.cc
+++ b/common/kernel/basectx.cc
@@ -131,6 +131,30 @@ void BaseCtx::constrainCellToRegion(IdString cell, IdString region_name)
     if (!matched)
         log_warning("No cell matched '%s' when constraining to region '%s'\n", nameOf(cell), nameOf(region_name));
 }
+
+void BaseCtx::createRegionPlug(IdString name, IdString type, Loc approx_loc)
+{
+    CellInfo *cell = nullptr;
+    if (cells.count(name))
+        cell = cells.at(name).get();
+    else
+        cell = createCell(name, type);
+    cell->pseudo_cell = std::make_unique<RegionPlug>(approx_loc);
+}
+
+void BaseCtx::addPlugPin(IdString plug, IdString pin, PortType dir, WireId wire)
+{
+    if (!cells.count(plug))
+        log_error("no cell named '%s' found\n", plug.c_str(this));
+    CellInfo *ci = cells.at(plug).get();
+    RegionPlug *rplug = dynamic_cast<RegionPlug *>(ci->pseudo_cell.get());
+    if (!rplug)
+        log_error("cell '%s' is not a RegionPlug\n", plug.c_str(this));
+    rplug->port_wires[pin] = wire;
+    ci->ports[pin].name = pin;
+    ci->ports[pin].type = dir;
+}
+
 DecalXY BaseCtx::constructDecalXY(DecalId decal, float x, float y)
 {
     DecalXY dxy;