From 30f122854a6dd00f81fc15e7c9384644dd90385b Mon Sep 17 00:00:00 2001
From: David Shah <davey1576@gmail.com>
Date: Thu, 26 Jul 2018 13:05:15 +0200
Subject: [PATCH] ecp5: Helper function and arch tweaks for global router

Signed-off-by: David Shah <davey1576@gmail.com>
---
 ecp5/arch.cc    |  6 ++++++
 ecp5/arch.h     | 23 ++++++++++++++++++++++
 ecp5/globals.cc | 52 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 81 insertions(+)
 create mode 100644 ecp5/globals.cc

diff --git a/ecp5/arch.cc b/ecp5/arch.cc
index 82ebfba1..6b701a32 100644
--- a/ecp5/arch.cc
+++ b/ecp5/arch.cc
@@ -579,4 +579,10 @@ std::vector<std::pair<std::string, std::string>> Arch::getTilesAtLocation(int ro
     return ret;
 }
 
+GlobalInfoPOD Arch::globalInfoAtLoc(Location loc)
+{
+    int locidx = loc.y * chip_info->width + loc.x;
+    return chip_info->location_glbinfo[locidx];
+}
+
 NEXTPNR_NAMESPACE_END
diff --git a/ecp5/arch.h b/ecp5/arch.h
index da86d4e2..1908f122 100644
--- a/ecp5/arch.h
+++ b/ecp5/arch.h
@@ -640,6 +640,21 @@ struct Arch : BaseCtx
         return range;
     }
 
+    IdString getWireBasename(WireId wire) const { return id(locInfo(wire)->wire_data[wire.index].name.get()); }
+
+    WireId getWireByLocAndBasename(Location loc, std::string basename) const
+    {
+        WireId wireId;
+        wireId.location = loc;
+        for (int i = 0; i < locInfo(wireId)->num_wires; i++) {
+            if (locInfo(wireId)->wire_data[i].name.get() == basename) {
+                wireId.index = i;
+                return wireId;
+            }
+        }
+        return WireId();
+    }
+
     // -------------------------------------------------
 
     PipId getPipByName(IdString name) const;
@@ -891,6 +906,14 @@ struct Arch : BaseCtx
         }
         NPNR_ASSERT_FALSE_STR("no tile at (" + std::to_string(col) + ", " + std::to_string(row) + ") with type in set");
     }
+
+    GlobalInfoPOD globalInfoAtLoc(Location loc);
+
+    IdString id_trellis_slice;
+    IdString id_clk, id_lsr;
+    IdString id_clkmux, id_lsrmux;
+    IdString id_srmode, id_mode;
+
 };
 
 NEXTPNR_NAMESPACE_END
diff --git a/ecp5/globals.cc b/ecp5/globals.cc
new file mode 100644
index 00000000..d435ca93
--- /dev/null
+++ b/ecp5/globals.cc
@@ -0,0 +1,52 @@
+/*
+ *  nextpnr -- Next Generation Place and Route
+ *
+ *  Copyright (C) 2018  David Shah <david@symbioticeda.com>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "nextpnr.h"
+
+NEXTPNR_NAMESPACE_BEGIN
+
+class Ecp5GlobalRouter
+{
+  public:
+    Ecp5GlobalRouter(Context *ctx) : ctx(ctx){};
+
+    PipId find_tap_pip(WireId tile_glb)
+    {
+        std::string wireName = ctx->getWireBasename(tile_glb).str(ctx);
+        std::string glbName = wireName.substr(2);
+        TapDirection td = ctx->globalInfoAtLoc(tile_glb.location).tap_dir;
+        WireId tap_wire;
+        Location tap_loc;
+        tap_loc.x = ctx->globalInfoAtLoc(tile_glb.location).tap_col;
+        tap_loc.y = tile_glb.location.y;
+        if (td == TAP_DIR_LEFT) {
+            tap_wire = ctx->getWireByLocAndBasename(tap_loc, "L_" + glbName);
+        } else {
+            tap_wire = ctx->getWireByLocAndBasename(tap_loc, "R_" + glbName);
+        }
+        return *(ctx->getPipsUphill(tap_wire).begin());
+    }
+
+  private:
+    Context *ctx;
+};
+
+void route_ecp5_globals(Context *ctx);
+
+NEXTPNR_NAMESPACE_END