Added ff and latch support to read_liberty
authorClifford Wolf <clifford@clifford.at>
Sat, 15 Feb 2014 18:36:33 +0000 (19:36 +0100)
committerClifford Wolf <clifford@clifford.at>
Sat, 15 Feb 2014 18:44:19 +0000 (19:44 +0100)
frontends/liberty/liberty.cc

index ca899cb95fe4c912a7b8c8d69da9c1071b60a3b7..485d28ee1634a231eafe88604befbe0c937cf22a 100644 (file)
@@ -160,7 +160,7 @@ static bool parse_func_reduce(RTLIL::Module *module, std::vector<token_t> &stack
        }
 
        if (0 <= top && stack[top].type == 2) {
-               if (next_token.type == '*' || next_token.type == '&' || next_token.type == 0)
+               if (next_token.type == '*' || next_token.type == '&' || next_token.type == 0 || next_token.type == '(')
                        return false;
                stack[top].type = 3;
                return true;
@@ -225,6 +225,223 @@ static RTLIL::SigSpec parse_func_expr(RTLIL::Module *module, const char *expr)
        return stack.back().sig;
 }
 
+static void create_ff(RTLIL::Module *module, LibertyAst *node)
+{
+       RTLIL::SigSpec iq_sig(module->new_wire(1, RTLIL::escape_id(node->args.at(0))));
+       RTLIL::SigSpec iqn_sig(module->new_wire(1, RTLIL::escape_id(node->args.at(1))));
+
+       RTLIL::SigSpec clk_sig, data_sig, clear_sig, preset_sig;
+       bool clk_polarity = true, clear_polarity = true, preset_polarity = true;
+
+       for (auto child : node->children) {
+               if (child->id == "clocked_on")
+                       clk_sig = parse_func_expr(module, child->value.c_str());
+               if (child->id == "next_state")
+                       data_sig = parse_func_expr(module, child->value.c_str());
+               if (child->id == "clear")
+                       clear_sig = parse_func_expr(module, child->value.c_str());
+               if (child->id == "preset")
+                       preset_sig = parse_func_expr(module, child->value.c_str());
+       }
+
+       if (clk_sig.width == 0 || data_sig.width == 0)
+               log_error("FF cell %s has no next_state and/or clocked_on attribute.\n", RTLIL::id2cstr(module->name));
+
+       for (bool rerun_invert_rollback = true; rerun_invert_rollback;)
+       {
+               rerun_invert_rollback = false;
+
+               for (auto &it : module->cells) {
+                       if (it.second->type == "$_INV_" && it.second->connections.at("\\Y") == clk_sig) {
+                               clk_sig = it.second->connections.at("\\A");
+                               clk_polarity = !clk_polarity;
+                               rerun_invert_rollback = true;
+                       }
+                       if (it.second->type == "$_INV_" && it.second->connections.at("\\Y") == clear_sig) {
+                               clear_sig = it.second->connections.at("\\A");
+                               clear_polarity = !clear_polarity;
+                               rerun_invert_rollback = true;
+                       }
+                       if (it.second->type == "$_INV_" && it.second->connections.at("\\Y") == preset_sig) {
+                               preset_sig = it.second->connections.at("\\A");
+                               preset_polarity = !preset_polarity;
+                               rerun_invert_rollback = true;
+                       }
+               }
+       }
+
+       RTLIL::Cell *cell = new RTLIL::Cell;
+       cell->name = NEW_ID;
+       cell->type = "$_INV_";
+       cell->connections["\\A"] = iq_sig;
+       cell->connections["\\Y"] = iqn_sig;
+       module->add(cell);
+
+       cell = new RTLIL::Cell;
+       cell->name = NEW_ID;
+       cell->connections["\\D"] = data_sig;
+       cell->connections["\\Q"] = iq_sig;
+       cell->connections["\\C"] = clk_sig;
+       module->add(cell);
+
+       if (clear_sig.width == 0 && preset_sig.width == 0) {
+               cell->type = stringf("$_DFF_%c_", clk_polarity ? 'P' : 'N');
+       }
+
+       if (clear_sig.width == 1 && preset_sig.width == 0) {
+               cell->type = stringf("$_DFF_%c%c0_", clk_polarity ? 'P' : 'N', clear_polarity ? 'P' : 'N');
+               cell->connections["\\R"] = clear_sig;
+       }
+
+       if (clear_sig.width == 0 && preset_sig.width == 1) {
+               cell->type = stringf("$_DFF_%c%c1_", clk_polarity ? 'P' : 'N', preset_polarity ? 'P' : 'N');
+               cell->connections["\\R"] = preset_sig;
+       }
+
+       if (clear_sig.width == 1 && preset_sig.width == 1) {
+               cell->type = stringf("$_DFFSR_%c%c%c_", clk_polarity ? 'P' : 'N', preset_polarity ? 'P' : 'N', clear_polarity ? 'P' : 'N');
+               cell->connections["\\S"] = preset_sig;
+               cell->connections["\\R"] = clear_sig;
+       }
+
+       log_assert(!cell->type.empty());
+}
+
+static void create_latch(RTLIL::Module *module, LibertyAst *node)
+{
+       RTLIL::SigSpec iq_sig(module->new_wire(1, RTLIL::escape_id(node->args.at(0))));
+       RTLIL::SigSpec iqn_sig(module->new_wire(1, RTLIL::escape_id(node->args.at(1))));
+
+       RTLIL::SigSpec enable_sig, data_sig, clear_sig, preset_sig;
+       bool enable_polarity = true, clear_polarity = true, preset_polarity = true;
+
+       for (auto child : node->children) {
+               if (child->id == "enable")
+                       enable_sig = parse_func_expr(module, child->value.c_str());
+               if (child->id == "data_in")
+                       data_sig = parse_func_expr(module, child->value.c_str());
+               if (child->id == "clear")
+                       clear_sig = parse_func_expr(module, child->value.c_str());
+               if (child->id == "preset")
+                       preset_sig = parse_func_expr(module, child->value.c_str());
+       }
+
+       if (enable_sig.width == 0 || data_sig.width == 0)
+               log_error("Latch cell %s has no data_in and/or enable attribute.\n", RTLIL::id2cstr(module->name));
+
+       for (bool rerun_invert_rollback = true; rerun_invert_rollback;)
+       {
+               rerun_invert_rollback = false;
+
+               for (auto &it : module->cells) {
+                       if (it.second->type == "$_INV_" && it.second->connections.at("\\Y") == enable_sig) {
+                               enable_sig = it.second->connections.at("\\A");
+                               enable_polarity = !enable_polarity;
+                               rerun_invert_rollback = true;
+                       }
+                       if (it.second->type == "$_INV_" && it.second->connections.at("\\Y") == clear_sig) {
+                               clear_sig = it.second->connections.at("\\A");
+                               clear_polarity = !clear_polarity;
+                               rerun_invert_rollback = true;
+                       }
+                       if (it.second->type == "$_INV_" && it.second->connections.at("\\Y") == preset_sig) {
+                               preset_sig = it.second->connections.at("\\A");
+                               preset_polarity = !preset_polarity;
+                               rerun_invert_rollback = true;
+                       }
+               }
+       }
+
+       RTLIL::Cell *cell = new RTLIL::Cell;
+       cell->name = NEW_ID;
+       cell->type = "$_INV_";
+       cell->connections["\\A"] = iq_sig;
+       cell->connections["\\Y"] = iqn_sig;
+       module->add(cell);
+
+       if (clear_sig.width == 1)
+       {
+               RTLIL::SigSpec clear_negative = clear_sig;
+               RTLIL::SigSpec clear_enable = clear_sig;
+
+               if (clear_polarity == true || clear_polarity != enable_polarity)
+               {
+                       RTLIL::Cell *inv = new RTLIL::Cell;
+                       inv->name = NEW_ID;
+                       inv->type = "$_INV_";
+                       inv->connections["\\A"] = clear_sig;
+                       inv->connections["\\Y"] = NEW_WIRE(module, 1);;
+                       module->add(inv);
+
+                       if (clear_polarity == true)
+                               clear_negative = inv->connections["\\Y"];
+                       if (clear_polarity != enable_polarity)
+                               clear_enable = inv->connections["\\Y"];
+               }
+
+               RTLIL::Cell *data_gate = new RTLIL::Cell;
+               data_gate->name = NEW_ID;
+               data_gate->type = "$_AND_";
+               data_gate->connections["\\A"] = data_sig;
+               data_gate->connections["\\B"] = clear_negative;
+               data_gate->connections["\\Y"] = data_sig = NEW_WIRE(module, 1);;
+               module->add(data_gate);
+
+               RTLIL::Cell *enable_gate = new RTLIL::Cell;
+               enable_gate->name = NEW_ID;
+               enable_gate->type = enable_polarity ? "$_OR_" : "$_AND_";
+               enable_gate->connections["\\A"] = enable_sig;
+               enable_gate->connections["\\B"] = clear_enable;
+               enable_gate->connections["\\Y"] = data_sig = NEW_WIRE(module, 1);;
+               module->add(enable_gate);
+       }
+
+       if (preset_sig.width == 1)
+       {
+               RTLIL::SigSpec preset_positive = preset_sig;
+               RTLIL::SigSpec preset_enable = preset_sig;
+
+               if (preset_polarity == false || preset_polarity != enable_polarity)
+               {
+                       RTLIL::Cell *inv = new RTLIL::Cell;
+                       inv->name = NEW_ID;
+                       inv->type = "$_INV_";
+                       inv->connections["\\A"] = preset_sig;
+                       inv->connections["\\Y"] = NEW_WIRE(module, 1);;
+                       module->add(inv);
+
+                       if (preset_polarity == false)
+                               preset_positive = inv->connections["\\Y"];
+                       if (preset_polarity != enable_polarity)
+                               preset_enable = inv->connections["\\Y"];
+               }
+
+               RTLIL::Cell *data_gate = new RTLIL::Cell;
+               data_gate->name = NEW_ID;
+               data_gate->type = "$_OR_";
+               data_gate->connections["\\A"] = data_sig;
+               data_gate->connections["\\B"] = preset_positive;
+               data_gate->connections["\\Y"] = data_sig = NEW_WIRE(module, 1);;
+               module->add(data_gate);
+
+               RTLIL::Cell *enable_gate = new RTLIL::Cell;
+               enable_gate->name = NEW_ID;
+               enable_gate->type = enable_polarity ? "$_OR_" : "$_AND_";
+               enable_gate->connections["\\A"] = enable_sig;
+               enable_gate->connections["\\B"] = preset_enable;
+               enable_gate->connections["\\Y"] = data_sig = NEW_WIRE(module, 1);;
+               module->add(enable_gate);
+       }
+
+       cell = new RTLIL::Cell;
+       cell->name = NEW_ID;
+       cell->type = stringf("$_DLATCH_%c_", enable_polarity ? 'P' : 'N');
+       cell->connections["\\D"] = data_sig;
+       cell->connections["\\Q"] = iq_sig;
+       cell->connections["\\E"] = enable_sig;
+       module->add(cell);
+}
+
 struct LibertyFrontend : public Frontend {
        LibertyFrontend() : Frontend("liberty", "read cells from liberty file") { }
        virtual void help()
@@ -289,21 +506,6 @@ struct LibertyFrontend : public Frontend {
                                log_error("Duplicate definition of cell/module %s.\n", RTLIL::id2cstr(cell_name));
                        }
 
-                       if (!flag_lib)
-                       {
-                               LibertyAst *ff = cell->find("ff");
-                               if (ff != NULL) {
-                                       log("Warning: skipping flip-flop cell %s.\n", RTLIL::id2cstr(cell_name));
-                                       continue;
-                               }
-
-                               LibertyAst *latch = cell->find("latch");
-                               if (latch != NULL) {
-                                       log("Warning: skipping latch cell %s.\n", RTLIL::id2cstr(cell_name));
-                                       continue;
-                               }
-                       }
-
                        // log("Processing cell type %s.\n", RTLIL::id2cstr(cell_name));
                        cell_count++;
 
@@ -314,39 +516,51 @@ struct LibertyFrontend : public Frontend {
                        for (auto &attr : attributes)
                                module->attributes[attr] = 1;
 
-                       for (auto pin : cell->children)
-                       {
-                               if (pin->id != "pin" || pin->args.size() != 1)
-                                       continue;
+                       for (auto node : cell->children)
+                               if (node->id == "pin" && node->args.size() == 1) {
+                                       LibertyAst *dir = node->find("direction");
+                                       if (!dir || (dir->value != "input" && dir->value != "output" && dir->value != "internal"))
+                                               log_error("Missing or invalid dircetion for pin %s of cell %s.\n", node->args.at(0).c_str(), RTLIL::id2cstr(module->name));
+                                       if (!flag_lib || dir->value != "internal")
+                                               module->new_wire(1, RTLIL::escape_id(node->args.at(0)));
+                               }
 
-                               LibertyAst *dir = pin->find("direction");
-                               if (dir == NULL || dir->value == "internal")
-                                       continue;
+                       for (auto node : cell->children)
+                       {
+                               if (!flag_lib) {
+                                       if (node->id == "ff" && node->args.size() == 2)
+                                               create_ff(module, node);
+                                       if (node->id == "latch" && node->args.size() == 2)
+                                               create_latch(module, node);
+                               }
 
-                               log_assert(dir->value == "input" || dir->value == "output");
+                               if (node->id == "pin" && node->args.size() == 1)
+                               {
+                                       LibertyAst *dir = node->find("direction");
 
-                               RTLIL::Wire *wire = new RTLIL::Wire;
-                               wire->name = RTLIL::escape_id(pin->args.at(0));
-                               module->add(wire);
+                                       if (flag_lib && dir->value == "internal")
+                                               continue;
 
-                               if (dir->value == "input") {
-                                       wire->port_input = true;
-                                       continue;
-                               }
+                                       RTLIL::Wire *wire = module->wires.at(RTLIL::escape_id(node->args.at(0)));
 
-                               wire->port_output = true;
+                                       if (dir && dir->value == "input") {
+                                               wire->port_input = true;
+                                               continue;
+                                       }
 
-                               if (flag_lib)
-                                       continue;
+                                       if (dir && dir->value == "output")
+                                               wire->port_output = true;
 
-                               LibertyAst *func = pin->find("function");
-                               if (func == NULL)
-                                       log_error("Missing function on output %s of cell %s.\n", RTLIL::id2cstr(wire->name), RTLIL::id2cstr(module->name));
+                                       if (flag_lib)
+                                               continue;
 
-                               RTLIL::SigSpec out_sig = parse_func_expr(module, func->value.c_str());
-                               module->connections.push_back(RTLIL::SigSig(wire, out_sig));
+                                       LibertyAst *func = node->find("function");
+                                       if (func == NULL)
+                                               log_error("Missing function on output %s of cell %s.\n", RTLIL::id2cstr(wire->name), RTLIL::id2cstr(module->name));
 
-                               continue;
+                                       RTLIL::SigSpec out_sig = parse_func_expr(module, func->value.c_str());
+                                       module->connections.push_back(RTLIL::SigSig(wire, out_sig));
+                               }
                        }
 
                        module->fixup_ports();