Add "nextpnr-ice40 --tmfuzz"

Signed-off-by: Clifford Wolf <clifford@clifford.at>

3 files changed, 52 insertions, 0 deletions

diff --git a/common/route.cc b/common/route.cc
index 657075ce..39e420d3 100644
--- a/common/route.cc
+++ b/common/route.cc
@@ -161,6 +161,7 @@ struct Router
         std::unordered_map<WireId, delay_t> src_wires;
         src_wires[src_wire] = 0;
         route(src_wires, dst_wire);
+        routedOkay = visited.count(dst_wire);
     }
 
     Router(Context *ctx, IdString net_name, bool ripup = false,
@@ -526,4 +527,13 @@ bool route_design(Context *ctx)
     return true;
 }
 
+bool get_actual_route_delay(Context *ctx, WireId src_wire, WireId dst_wire,
+                            delay_t &delay)
+{
+    Router router(ctx, src_wire, dst_wire);
+    if (router.routedOkay)
+        delay = router.visited.at(dst_wire).delay;
+    return router.routedOkay;
+}
+
 NEXTPNR_NAMESPACE_END
diff --git a/common/route.h b/common/route.h
index 33927f26..af0de42e 100644
--- a/common/route.h
+++ b/common/route.h
@@ -25,6 +25,8 @@
 NEXTPNR_NAMESPACE_BEGIN
 
 extern bool route_design(Context *ctx);
+extern bool get_actual_route_delay(Context *ctx, WireId src_wire,
+                                   WireId dst_wire, delay_t &delay);
 
 NEXTPNR_NAMESPACE_END
 
diff --git a/ice40/main.cc b/ice40/main.cc
index 8a04caf6..ea7c9a66 100644
--- a/ice40/main.cc
+++ b/ice40/main.cc
@@ -86,6 +86,7 @@ int main(int argc, char *argv[])
     options.add_options()("seed", po::value<int>(),
                           "seed value for random number generator");
     options.add_options()("version,V", "show version");
+    options.add_options()("tmfuzz", "run path delay estimate fuzzer");
     options.add_options()("lp384", "set device type to iCE40LP384");
     options.add_options()("lp1k", "set device type to iCE40LP1K");
     options.add_options()("lp8k", "set device type to iCE40LP8K");
@@ -220,6 +221,45 @@ int main(int argc, char *argv[])
         std::cout << "</svg>\n";
     }
 
+    if (vm.count("tmfuzz")) {
+        std::vector<WireId> src_wires, dst_wires;
+
+        for (auto w : ctx.getWires())
+            src_wires.push_back(w);
+
+        for (auto b : ctx.getBels()) {
+            if (ctx.getBelType(b) == TYPE_ICESTORM_LC) {
+                dst_wires.push_back(ctx.getWireBelPin(b, PIN_I0));
+                dst_wires.push_back(ctx.getWireBelPin(b, PIN_I1));
+                dst_wires.push_back(ctx.getWireBelPin(b, PIN_I2));
+                dst_wires.push_back(ctx.getWireBelPin(b, PIN_I3));
+                dst_wires.push_back(ctx.getWireBelPin(b, PIN_CEN));
+                dst_wires.push_back(ctx.getWireBelPin(b, PIN_CIN));
+            }
+            if (ctx.getBelType(b) == TYPE_SB_IO) {
+                dst_wires.push_back(ctx.getWireBelPin(b, PIN_D_OUT_0));
+                dst_wires.push_back(ctx.getWireBelPin(b, PIN_OUTPUT_ENABLE));
+            }
+        }
+
+        ctx.shuffle(src_wires);
+        ctx.shuffle(dst_wires);
+
+        for (int i = 0; i < int(src_wires.size()) && i < int(dst_wires.size());
+             i++) {
+            delay_t actual_delay;
+            if (!get_actual_route_delay(&ctx, src_wires[i], dst_wires[i],
+                                        actual_delay))
+                continue;
+            printf("%s %s %.3f %.3f\n",
+                   ctx.getWireName(src_wires[i]).c_str(&ctx),
+                   ctx.getWireName(dst_wires[i]).c_str(&ctx),
+                   ctx.getDelayNS(actual_delay),
+                   ctx.getDelayNS(
+                           ctx.estimateDelay(src_wires[i], dst_wires[i])));
+        }
+    }
+
     if (vm.count("json")) {
         std::string filename = vm["json"].as<std::string>();
         std::istream *f = new std::ifstream(filename);