Merge branch 'YosysHQ:main' into main

README.md

@@ -266,6 +266,16 @@ The command ``prep`` provides a good default word-level synthesis script, as
 used in SMT-based formal verification.
 
 
+Additional information
+======================
+
+The ``read_verilog`` command, used by default when calling ``read`` with Verilog
+source input, does not perform syntax checking.  You should instead lint your
+source with another tool such as
+[Verilator](https://www.veripool.org/verilator/) first, e.g. by calling
+``verilator --lint-only``.
+
+
 Unsupported Verilog-2005 Features
 =================================
 

backends/json/json.cc

@@ -353,6 +353,9 @@ struct JsonBackend : public Backend {
 		log("        emit 32-bit or smaller fully-defined parameter values directly\n");
 		log("        as JSON numbers (for compatibility with old parsers)\n");
 		log("\n");
+		log("    -selected\n");
+		log("        output only select module\n");
+		log("\n");
 		log("\n");
 		log("The general syntax of the JSON output created by this command is as follows:\n");
 		log("\n");
@@ -597,6 +600,7 @@ struct JsonBackend : public Backend {
 	{
 		bool aig_mode = false;
 		bool compat_int_mode = false;
+		bool use_selection = false;
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
@@ -609,13 +613,17 @@ struct JsonBackend : public Backend {
 				compat_int_mode = true;
 				continue;
 			}
+			if (args[argidx] == "-selected") {
+				use_selection = true;
+				continue;
+			}
 			break;
 		}
 		extra_args(f, filename, args, argidx);
 
 		log_header(design, "Executing JSON backend.\n");
 
-		JsonWriter json_writer(*f, false, aig_mode, compat_int_mode);
+		JsonWriter json_writer(*f, use_selection, aig_mode, compat_int_mode);
 		json_writer.write_design(design);
 	}
 } JsonBackend;

docs/source/code_examples/fifo/fifo.v

@@ -5,7 +5,7 @@ module addr_gen
 ) ( input en, clk, rst,
 	output reg [AWIDTH-1:0] addr
 );
-	initial addr <= 0;
+	initial addr = 0;
 
 	// async reset
 	// increment address when enabled
@@ -13,7 +13,7 @@ module addr_gen
 		if (rst)
 			addr <= 0;
 		else if (en) begin
-			if (addr == MAX_DATA-1)
+			if ({'0, addr} == MAX_DATA-1)
 				addr <= 0;
 			else
 				addr <= addr + 1;
@@ -57,7 +57,7 @@ module fifo
 	);
 
 	// status signals
-	initial count <= 0;
+	initial count = 0;
 
 	always @(posedge clk or posedge rst) begin
 		if (rst)

docs/source/getting_started/example_synth.rst

@@ -30,6 +30,14 @@ First, let's quickly look at the design we'll be synthesizing:
 
 .. todo:: fifo.v description
 
+While the open source `read_verilog` frontend generally does a pretty good job
+at processing valid Verilog input, it does not provide very good error handling
+or reporting.  Using an external tool such as `verilator`_ before running Yosys
+is highly recommended. We can quickly check the Verilog syntax of our design by
+calling ``verilator --lint-only fifo.v``.
+
+.. _verilator: https://www.veripool.org/verilator/
+
 Loading the design
 ~~~~~~~~~~~~~~~~~~
 

docs/source/introduction.rst

@@ -69,9 +69,14 @@ Things you can't do
 
   - Check out `nextpnr`_ for that
 
+- Rely on built-in syntax checking
+
+  - Use an external tool like `verilator`_ instead
+
 .. todo:: nextpnr for FPGAs, consider mentioning openlane, vpr, coriolis
 
 .. _nextpnr: https://github.com/YosysHQ/nextpnr
+.. _verilator: https://www.veripool.org/verilator/
 
 The Yosys family
 ----------------

frontends/liberty/liberty.cc

@@ -462,6 +462,9 @@ struct LibertyFrontend : public Frontend {
 		log("    -ignore_miss_data_latch\n");
 		log("        ignore latches with missing data and/or enable pins\n");
 		log("\n");
+		log("    -ignore_buses\n");
+		log("        ignore cells with bus interfaces (wide ports)\n");
+		log("\n");
 		log("    -setattr <attribute_name>\n");
 		log("        set the specified attribute (to the value 1) on all loaded modules\n");
 		log("\n");
@@ -478,6 +481,7 @@ struct LibertyFrontend : public Frontend {
 		bool flag_ignore_miss_func = false;
 		bool flag_ignore_miss_dir  = false;
 		bool flag_ignore_miss_data_latch = false;
+		bool flag_ignore_buses = false;
 		bool flag_unit_delay = false;
 		std::vector<std::string> attributes;
 
@@ -514,6 +518,10 @@ struct LibertyFrontend : public Frontend {
 				flag_ignore_miss_data_latch = true;
 				continue;
 			}
+			if (arg == "-ignore_buses") {
+				flag_ignore_buses = true;
+				continue;
+			}
 			if (arg == "-setattr" && argidx+1 < args.size()) {
 				attributes.push_back(RTLIL::escape_id(args[++argidx]));
 				continue;
@@ -546,27 +554,13 @@ struct LibertyFrontend : public Frontend {
 			if (cell->id != "cell" || cell->args.size() != 1)
 				continue;
 
-			std::string cell_name = RTLIL::escape_id(cell->args.at(0));
-
-			if (design->has(cell_name)) {
-				Module *existing_mod = design->module(cell_name);
-				if (!flag_nooverwrite && !flag_overwrite && !existing_mod->get_bool_attribute(ID::blackbox)) {
-					log_error("Re-definition of cell/module %s!\n", log_id(cell_name));
-				} else if (flag_nooverwrite) {
-					log("Ignoring re-definition of module %s.\n", log_id(cell_name));
-					continue;
-				} else {
-					log("Replacing existing%s module %s.\n", existing_mod->get_bool_attribute(ID::blackbox) ? " blackbox" : "", log_id(cell_name));
-					design->remove(existing_mod);
-				}
-			}
-
 			// log("Processing cell type %s.\n", RTLIL::unescape_id(cell_name).c_str());
 
 			std::map<std::string, std::tuple<int, int, bool>> type_map = global_type_map;
 			parse_type_map(type_map, cell);
 
 			RTLIL::Module *module = new RTLIL::Module;
+			std::string cell_name = RTLIL::escape_id(cell->args.at(0));
 			module->name = cell_name;
 			if (leakage_power_unit != "")
 				module->attributes["\\leakage_power_unit"] = leakage_power_unit;
@@ -577,6 +571,10 @@ struct LibertyFrontend : public Frontend {
 			if (flag_wb)
 				module->set_bool_attribute(ID::whitebox);
 
+			const LibertyAst *area = cell->find("area");
+			if (area)
+				module->attributes[ID::area] = area->value;
+
 			for (auto &attr : attributes)
 				module->attributes[attr] = 1;
 
@@ -607,6 +605,12 @@ struct LibertyFrontend : public Frontend {
 
 				if (node->id == "bus" && node->args.size() == 1)
 				{
+					if (flag_ignore_buses) {
+						log("Ignoring cell %s with a bus interface %s.\n", log_id(module->name), node->args.at(0).c_str());
+						delete module;
+						goto skip_cell;
+					}
+
 					if (!flag_lib)
 						log_error("Error in cell %s: bus interfaces are only supported in -lib mode.\n", log_id(cell_name));
 
@@ -720,6 +724,10 @@ struct LibertyFrontend : public Frontend {
 					RTLIL::Wire *wire = module->wires_.at(RTLIL::escape_id(node->args.at(0)));
 					log_assert(wire);
 
+					const LibertyAst *capacitance = node->find("capacitance");
+					if (capacitance)
+						wire->attributes[ID::capacitance] = capacitance->value;
+
 					if (dir && dir->value == "inout") {
 						wire->port_input = true;
 						wire->port_output = true;
@@ -797,6 +805,20 @@ struct LibertyFrontend : public Frontend {
 				}
 			}
 
+			if (design->has(cell_name)) {
+				Module *existing_mod = design->module(cell_name);
+				if (!flag_nooverwrite && !flag_overwrite && !existing_mod->get_bool_attribute(ID::blackbox)) {
+					log_error("Re-definition of cell/module %s!\n", log_id(cell_name));
+				} else if (flag_nooverwrite) {
+					log("Ignoring re-definition of module %s.\n", log_id(cell_name));
+					delete module;
+					goto skip_cell;
+				} else {
+					log("Replacing existing%s module %s.\n", existing_mod->get_bool_attribute(ID::blackbox) ? " blackbox" : "", log_id(cell_name));
+					design->remove(existing_mod);
+				}
+			}
+
 			module->fixup_ports();
 			design->add(module);
 			cell_count++;

kernel/constids.inc

@@ -274,3 +274,5 @@ X(X)
 X(xprop_decoder)
 X(Y)
 X(Y_WIDTH)
+X(area)
+X(capacitance)

kernel/rtlil.cc

@@ -1857,9 +1857,9 @@ namespace {
 				param_bits(ID::RD_COLLISION_X_MASK, max(1, param(ID::RD_PORTS) * param(ID::WR_PORTS)));
 				param_bits(ID::RD_WIDE_CONTINUATION, max(1, param(ID::RD_PORTS)));
 				param_bits(ID::RD_CE_OVER_SRST, max(1, param(ID::RD_PORTS)));
-				param_bits(ID::RD_ARST_VALUE, param(ID::RD_PORTS) * param(ID::WIDTH));
-				param_bits(ID::RD_SRST_VALUE, param(ID::RD_PORTS) * param(ID::WIDTH));
-				param_bits(ID::RD_INIT_VALUE, param(ID::RD_PORTS) * param(ID::WIDTH));
+				param_bits(ID::RD_ARST_VALUE, max(1, param(ID::RD_PORTS) * param(ID::WIDTH)));
+				param_bits(ID::RD_SRST_VALUE, max(1, param(ID::RD_PORTS) * param(ID::WIDTH)));
+				param_bits(ID::RD_INIT_VALUE, max(1, param(ID::RD_PORTS) * param(ID::WIDTH)));
 				param_bits(ID::WR_CLK_ENABLE, max(1, param(ID::WR_PORTS)));
 				param_bits(ID::WR_CLK_POLARITY, max(1, param(ID::WR_PORTS)));
 				param_bits(ID::WR_WIDE_CONTINUATION, max(1, param(ID::WR_PORTS)));

tests/liberty/.gitignore

@@ -1,3 +1,3 @@
 *.log
-*.filtered
+/*.filtered
 *.verilogsim

tests/liberty/foundry_data/.gitignore

@@ -0,0 +1,2 @@
+*.lib
+*.lib.filtered

tests/liberty/foundry_data/rules.txt

@@ -0,0 +1,16 @@
+-wire_load
+-wire_load_selection
+-default_wire_load
+-default_wire_load_area
+-default_wire_load_capacitance
+-default_wire_load_mode
+-default_wire_load_resistance
+-default_cell_leakage_power
+-default_wire_load_selection
+-default_leakage_power_density
+-lu_table_template
+-power_lut_template
+-leakage_power
+-cell_leakage_power
+-leakage_power
+-internal_power

tests/liberty/options_test.ys

@@ -0,0 +1,23 @@
+# Test memory macro gets ignored due to -ignore_buses
+read_verilog -noblackbox <<EOF
+module RM_IHPSG13_1P_64x64_c2_bm_bist();
+endmodule
+EOF
+read_liberty -lib -ignore_buses foundry_data/RM_IHPSG13_1P_64x64_c2_bm_bist_typ_1p20V_25C.lib.filtered.gz
+
+# Test memory macro doesn't get ignored without -ignore_buses
+# and check the area and capacitance attributes are populated
+design -reset
+read_liberty -lib foundry_data/RM_IHPSG13_1P_64x64_c2_bm_bist_typ_1p20V_25C.lib.filtered.gz
+select -assert-mod-count 1 =RM_IHPSG13_1P_64x64_c2_bm_bist =A:area=50489.1328 %i
+select -assert-any =*/i:A_BIST_EN =*/a:capacitance=0.00401111 %i
+
+# Test import of unit delay arcs
+design -reset
+read_liberty -wb -unit_delay -ignore_miss_func foundry_data/sg13g2_stdcell_typ_1p20V_25C.lib.filtered.gz
+
+# A->Y arc on nand2_1 exists
+select -assert-any =sg13g2_nand2_1/i:A %co1:+$specify2[SRC] =sg13g2_nand2_1/o:Y %co1:+$specify2[DST] %i
+
+# D->Q arc on sdfbbp_1 doesn't
+select -assert-none =sg13g2_sdfbbp_1/i:D %co1:+$specify2[SRC] =sg13g2_nand2_1/o:Q %co1:+$specify2[DST] %i

tests/liberty/unit_delay.ys

@@ -1,3 +0,0 @@
-# Nothing gets imported: the file lacks timing data
-read_liberty -wb -unit_delay normal.lib
-select -assert-none =*/t:$specify*

tests/memories/nordports.ys

@@ -0,0 +1,9 @@
+# check memory_collect doesn't produce invalid RTLIL on a memory w/o read ports
+read_rtlil <<EOF
+autoidx 1
+attribute \top 1
+module \top
+  memory width 4 size 3 \foo
+end
+EOF
+memory_collect