ecp5: Add --out-of-context for building hard macros

Signed-off-by: David Shah <dave@ds0.me>

common/nextpnr.cc

@@ -294,6 +294,9 @@ delay_t Context::getNetinfoRouteDelay(const NetInfo *net_info, const PortRef &us
             break;
 
         PipId pip = it->second.pip;
+        if (pip == PipId())
+            break;
+
         delay += getPipDelay(pip).maxDelay();
         delay += getWireDelay(cursor).maxDelay();
         cursor = getPipSrcWire(pip);
@@ -571,6 +574,16 @@ void BaseCtx::attributesToArchInfo()
             BelId b = getCtx()->getBelByName(id(val->second.as_string()));
             getCtx()->bindBel(b, ci, strength);
         }
+
+        val = ci->attrs.find(id("CONSTR_PARENT"));
+        if (val != ci->attrs.end()) {
+            auto parent = cells.find(id(val->second.str));
+            if (parent != cells.end())
+                ci->constr_parent = parent->second.get();
+            else
+                continue;
+        }
+
         val = ci->attrs.find(id("CONSTR_X"));
         if (val != ci->attrs.end())
             ci->constr_x = val->second.as_int64();
@@ -599,7 +612,8 @@ void BaseCtx::attributesToArchInfo()
             auto children = val->second.as_string();
             boost::split(strs, children, boost::is_any_of(";"));
             for (auto val : strs) {
-                ci->constr_children.push_back(cells.find(id(val.c_str()))->second.get());
+                if (cells.count(id(val.c_str())))
+                    ci->constr_children.push_back(cells.find(id(val.c_str()))->second.get());
             }
         }
     }

ecp5/arch.cc

@@ -524,9 +524,15 @@ bool Arch::place()
     } else {
         log_error("ECP5 architecture does not support placer '%s'\n", placer.c_str());
     }
-
     permute_luts();
+
+    // In out-of-context mode, create a locked macro
+    if (bool_or_default(settings, id("arch.ooc")))
+        for (auto &cell : cells)
+            cell.second->belStrength = STRENGTH_LOCKED;
+
     getCtx()->settings[getCtx()->id("place")] = 1;
+
     archInfoToAttributes();
     return true;
 }

ecp5/arch_place.cc

@@ -152,7 +152,10 @@ void Arch::permute_luts()
             inputs.emplace_back(crit, i);
         }
         // Least critical first (A input is slowest)
-        std::sort(inputs.begin(), inputs.end());
+
+        // Avoid permuting locked LUTs (e.g. from an OOC submodule)
+        if (ci->belStrength <= STRENGTH_STRONG)
+            std::sort(inputs.begin(), inputs.end());
         for (int i = 0; i < 4; i++) {
             IdString p = port_names.at(i);
             // log_info("%s %s %f\n", p.c_str(ctx), port_names.at(inputs.at(i).second).c_str(ctx), inputs.at(i).first);

ecp5/bitstream.cc

@@ -789,15 +789,13 @@ void write_bitstream(Context *ctx, std::string base_config_file, std::string tex
 
             if (str_or_default(ci->params, ctx->id("MODE"), "LOGIC") == "CCU2") {
                 cc.tiles[tname].add_enum(slice + ".CCU2.INJECT1_0",
-                                         str_or_default(ci->params, ctx->id("INJECT1_0"), "YES"));
+                                         str_or_default(ci->params, ctx->id("CCU2_INJECT1_0"), "YES"));
                 cc.tiles[tname].add_enum(slice + ".CCU2.INJECT1_1",
-                                         str_or_default(ci->params, ctx->id("INJECT1_1"), "YES"));
+                                         str_or_default(ci->params, ctx->id("CCU2_INJECT1_1"), "YES"));
             } else {
                 // Don't interfere with cascade mux wiring
-                cc.tiles[tname].add_enum(slice + ".CCU2.INJECT1_0",
+                cc.tiles[tname].add_enum(slice + ".CCU2.INJECT1_0", "_NONE_");
-                                         str_or_default(ci->params, ctx->id("INJECT1_0"), "_NONE_"));
+                cc.tiles[tname].add_enum(slice + ".CCU2.INJECT1_1", "_NONE_");
-                cc.tiles[tname].add_enum(slice + ".CCU2.INJECT1_1",
-                                         str_or_default(ci->params, ctx->id("INJECT1_1"), "_NONE_"));
             }
 
             if (str_or_default(ci->params, ctx->id("MODE"), "LOGIC") == "DPRAM" && slice == "SLICEA") {

ecp5/cells.cc

@@ -274,8 +274,8 @@ void ccu2c_to_slice(Context *ctx, CellInfo *ccu, CellInfo *lc)
     lc->params[ctx->id("LUT0_INITVAL")] = get_or_default(ccu->params, ctx->id("INIT0"), Property(0, 16));
     lc->params[ctx->id("LUT1_INITVAL")] = get_or_default(ccu->params, ctx->id("INIT1"), Property(0, 16));
 
-    lc->params[ctx->id("INJECT1_0")] = str_or_default(ccu->params, ctx->id("INJECT1_0"), "YES");
+    lc->params[ctx->id("CCU2_INJECT1_0")] = str_or_default(ccu->params, ctx->id("INJECT1_0"), "YES");
-    lc->params[ctx->id("INJECT1_1")] = str_or_default(ccu->params, ctx->id("INJECT1_1"), "YES");
+    lc->params[ctx->id("CCU2_INJECT1_1")] = str_or_default(ccu->params, ctx->id("INJECT1_1"), "YES");
 
     replace_port(ccu, ctx->id("CIN"), lc, ctx->id("FCI"));
 

ecp5/globals.cc

@@ -431,11 +431,15 @@ class Ecp5GlobalRouter
   public:
     void promote_globals()
     {
+        bool is_ooc = bool_or_default(ctx->settings, ctx->id("arch.ooc"));
         log_info("Promoting globals...\n");
         auto clocks = get_clocks();
         for (auto clock : clocks) {
             log_info("    promoting clock net %s to global network\n", clock->name.c_str(ctx));
-            insert_dcc(clock);
+            if (is_ooc) // Don't actually do anything in OOC mode, global routing will be done in the full design
+                clock->is_global = true;
+            else
+                insert_dcc(clock);
         }
     }
 

ecp5/main.cc

@@ -71,6 +71,8 @@ po::options_description ECP5CommandHandler::getArchOptions()
     specific.add_options()("lpf", po::value<std::vector<std::string>>(), "LPF pin constraint file(s)");
     specific.add_options()("lpf-allow-unconstrained", "don't require LPF file(s) to constrain all IO");
 
+    specific.add_options()("out-of-context", "disable IO buffer insertion and global promotion/routing, for building pre-routed blocks (experimental)");
+
     return specific;
 }
 void ECP5CommandHandler::validate()
@@ -91,6 +93,9 @@ void ECP5CommandHandler::customBitstream(Context *ctx)
         basecfg = vm["basecfg"].as<std::string>();
     }
 
+    if (bool_or_default(ctx->settings, ctx->id("arch.ooc")) && vm.count("textcfg"))
+        log_error("bitstream generation is not available in out-of-context mode (use --write to create a post-PnR JSON design)\n");
+
     std::string textcfg;
     if (vm.count("textcfg"))
         textcfg = vm["textcfg"].as<std::string>();
@@ -228,6 +233,8 @@ std::unique_ptr<Context> ECP5CommandHandler::createContext(std::unordered_map<st
         ctx->settings[ctx->id(val.first)] = val.second;
     ctx->settings[ctx->id("arch.package")] = ctx->archArgs().package;
     ctx->settings[ctx->id("arch.speed")] = speedString(ctx->archArgs().speed);
+    if (vm.count("out-of-context"))
+        ctx->settings[ctx->id("arch.ooc")] = 1;
     return ctx;
 }
 

ecp5/pack.cc

@@ -356,7 +356,12 @@ class Ecp5Packer
                     ionet = ci->ports.at(ctx->id("I")).net;
                     trio = net_only_drives(ctx, ci->ports.at(ctx->id("I")).net, is_trellis_io, ctx->id("B"), true, ci);
                 }
-                if (trio != nullptr) {
+                if (bool_or_default(ctx->settings, ctx->id("arch.ooc"))) {
+                    // No IO buffer insertion in out-of-context mode, just remove the nextpnr buffer
+                    // and leave the top level port
+                    for (auto &port : ci->ports)
+                        disconnect_port(ctx, ci, port.first);
+                } else if (trio != nullptr) {
                     // Trivial case, TRELLIS_IO used. Just destroy the net and the
                     // iobuf
                     log_info("%s feeds TRELLIS_IO %s, removing %s %s.\n", ci->name.c_str(ctx), trio->name.c_str(ctx),
@@ -673,6 +678,7 @@ class Ecp5Packer
     CellInfo *make_carry_feed_out(NetInfo *carry, boost::optional<PortRef> chain_next = boost::optional<PortRef>())
     {
         std::unique_ptr<CellInfo> feedout = create_ecp5_cell(ctx, ctx->id("CCU2C"));
+
         feedout->params[ctx->id("INIT0")] = Property(0, 16);
         feedout->params[ctx->id("INIT1")] = Property(10, 16); // LUT4 = 0; LUT2 = A
         feedout->params[ctx->id("INJECT1_0")] = std::string("NO");