Add frequency setting and fix slack calculation

Signed-off-by: David Shah <davey1576@gmail.com>

3 files changed, 12 insertions, 8 deletions

diff --git a/common/place_sa.cc b/common/place_sa.cc
index e792474d..2f8fb122 100644
--- a/common/place_sa.cc
+++ b/common/place_sa.cc
@@ -334,7 +334,7 @@ class SAPlacer
                     load_cell->bel, ctx->portPinFromId(load.port));
             delay_t raw_wl = ctx->estimateDelay(drv_wire, user_wire);
             float slack =
-                    ctx->getDelayNS(raw_wl) - ctx->getDelayNS(load.budget);
+                    ctx->getDelayNS(load.budget) - ctx->getDelayNS(raw_wl);
             worst_slack = std::min(slack, worst_slack);
             int load_x, load_y;
             bool load_gb;
diff --git a/common/timing.cc b/common/timing.cc
index 8da26077..a7b37f9d 100644
--- a/common/timing.cc
+++ b/common/timing.cc
@@ -101,7 +101,6 @@ void assign_budget(Context *ctx, float default_clock)
             }
         }
     }
-    const bool debug = true;
 
     // Post-allocation check
     for (auto net : ctx->nets) {
@@ -111,11 +110,11 @@ void assign_budget(Context *ctx, float default_clock)
                             "timing budget of %fns\n",
                             user.cell->name.c_str(ctx), user.port.c_str(ctx),
                             net.first.c_str(ctx), ctx->getDelayNS(user.budget));
-            if (debug)
-                log_warning("port %s.%s, connected to net '%s', has "
-                            "timing budget of %fns\n",
-                            user.cell->name.c_str(ctx), user.port.c_str(ctx),
-                            net.first.c_str(ctx), ctx->getDelayNS(user.budget));
+            if (ctx->verbose)
+                log_info("port %s.%s, connected to net '%s', has "
+                         "timing budget of %fns\n",
+                         user.cell->name.c_str(ctx), user.port.c_str(ctx),
+                         net.first.c_str(ctx), ctx->getDelayNS(user.budget));
         }
     }
 }
diff --git a/ice40/main.cc b/ice40/main.cc
index 8143a902..fcf112e6 100644
--- a/ice40/main.cc
+++ b/ice40/main.cc
@@ -93,6 +93,8 @@ int main(int argc, char *argv[])
     options.add_options()("hx1k", "set device type to iCE40HX1K");
     options.add_options()("hx8k", "set device type to iCE40HX8K");
     options.add_options()("up5k", "set device type to iCE40UP5K");
+    options.add_options()("freq", po::value<double>(),
+                          "set target frequency for design in MHz");
     options.add_options()("package", po::value<std::string>(),
                           "set device package");
     po::positional_options_description pos;
@@ -286,7 +288,10 @@ int main(int argc, char *argv[])
 
         if (!pack_design(&ctx) && !ctx.force)
             log_error("Packing design failed.\n");
-        assign_budget(&ctx, 50e6);
+        double freq = 50e6;
+        if (vm.count("freq"))
+            freq = vm["freq"].as<double>() * 1e6;
+        assign_budget(&ctx, freq);
         print_utilisation(&ctx);
 
         if (!vm.count("pack-only")) {