Add constraint weight as a command line option

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

3 files changed, 14 insertions, 1 deletions

diff --git a/ice40/arch.cc b/ice40/arch.cc
index eff1d9b9..84856402 100644
--- a/ice40/arch.cc
+++ b/ice40/arch.cc
@@ -659,7 +659,11 @@ delay_t Arch::getBudgetOverride(const NetInfo *net_info, const PortRef &sink, de
 
 // -----------------------------------------------------------------------
 
-bool Arch::place() { return placer1(getCtx()); }
+bool Arch::place() {
+    Placer1Cfg cfg;
+    cfg.constraintWeight = placer_constraintWeight;
+    return placer1(getCtx(), cfg);
+}
 
 bool Arch::route()
 {
diff --git a/ice40/arch.h b/ice40/arch.h
index 98361132..b9b4f3c5 100644
--- a/ice40/arch.h
+++ b/ice40/arch.h
@@ -797,6 +797,9 @@ struct Arch : BaseCtx
         }
         NPNR_ASSERT_FALSE("Expected PLL pin to share an output with an SB_IO D_IN_{0,1}");
     }
+
+    float placer_constraintWeight = 10;
+
 };
 
 NEXTPNR_NAMESPACE_END
diff --git a/ice40/main.cc b/ice40/main.cc
index 41d264ad..60f5b444 100644
--- a/ice40/main.cc
+++ b/ice40/main.cc
@@ -106,6 +106,8 @@ int main(int argc, char *argv[])
         options.add_options()("seed", po::value<int>(), "seed value for random number generator");
         options.add_options()("slack_redist_iter", po::value<int>(),
                               "number of iterations between slack redistribution");
+        options.add_options()("cstrweight", po::value<float>(), "placer weighting for relative constraint satisfaction");
+
         options.add_options()("version,V", "show version");
         options.add_options()("tmfuzz", "run path delay estimate fuzzer");
         options.add_options()("test", "check architecture database integrity");
@@ -318,6 +320,10 @@ int main(int argc, char *argv[])
             ctx->slack_redist_iter = vm["slack_redist_iter"].as<int>();
         }
 
+        if (vm.count("cstrweight")) {
+            ctx->placer_constraintWeight = vm["cstrweight"].as<float>();
+        }
+
         if (vm.count("svg")) {
             std::cout << "<svg xmlns=\"http://www.w3.org/2000/svg\" "
                          "xmlns:xlink=\"http://www.w3.org/1999/xlink\">\n";