Synthesis support for SystemVerilog interfaces

This time doing the changes mostly in AST before RTLIL generation

2 files changed, 68 insertions, 0 deletions

diff --git a/frontends/verilog/verilog_lexer.l b/frontends/verilog/verilog_lexer.l
index 83921bf0b..8808c2675 100644
--- a/frontends/verilog/verilog_lexer.l
+++ b/frontends/verilog/verilog_lexer.l
@@ -150,6 +150,9 @@ YOSYS_NAMESPACE_END
 "specparam"    { return TOK_SPECPARAM; }
 "package"      { SV_KEYWORD(TOK_PACKAGE); }
 "endpackage"   { SV_KEYWORD(TOK_ENDPACKAGE); }
+"interface"    { SV_KEYWORD(TOK_INTERFACE); }
+"endinterface" { SV_KEYWORD(TOK_ENDINTERFACE); }
+"modport"      { SV_KEYWORD(TOK_MODPORT); }
 "parameter"    { return TOK_PARAMETER; }
 "localparam"   { return TOK_LOCALPARAM; }
 "defparam"     { return TOK_DEFPARAM; }
@@ -295,6 +298,11 @@ supply1 { return TOK_SUPPLY1; }
 	return TOK_ID;
 }
 
+[a-zA-Z_$][a-zA-Z0-9_$\.]* {
+	frontend_verilog_yylval.string = new std::string(std::string("\\") + yytext);
+    return TOK_ID;
+}
+
 "/*"[ \t]*(synopsys|synthesis)[ \t]*translate_off[ \t]*"*/" {
 	static bool printed_warning = false;
 	if (!printed_warning) {
diff --git a/frontends/verilog/verilog_parser.y b/frontends/verilog/verilog_parser.y
index 16cac1460..0ff5d576e 100644
--- a/frontends/verilog/verilog_parser.y
+++ b/frontends/verilog/verilog_parser.y
@@ -106,6 +106,7 @@ static void free_attr(std::map<std::string, AstNode*> *al)
 %token ATTR_BEGIN ATTR_END DEFATTR_BEGIN DEFATTR_END
 %token TOK_MODULE TOK_ENDMODULE TOK_PARAMETER TOK_LOCALPARAM TOK_DEFPARAM
 %token TOK_PACKAGE TOK_ENDPACKAGE TOK_PACKAGESEP
+%token TOK_INTERFACE TOK_ENDINTERFACE TOK_MODPORT
 %token TOK_INPUT TOK_OUTPUT TOK_INOUT TOK_WIRE TOK_REG TOK_LOGIC
 %token TOK_INTEGER TOK_SIGNED TOK_ASSIGN TOK_ALWAYS TOK_INITIAL
 %token TOK_BEGIN TOK_END TOK_IF TOK_ELSE TOK_FOR TOK_WHILE TOK_REPEAT
@@ -168,6 +169,7 @@ design:
 	param_decl design |
 	localparam_decl design |
 	package design |
+	interface design |
 	/* empty */;
 
 attr:
@@ -320,6 +322,21 @@ module_arg:
 		}
 		delete $1;
 	} module_arg_opt_assignment |
+	TOK_ID {
+		astbuf1 = new AstNode(AST_INTERFACEPORT);
+		astbuf1->children.push_back(new AstNode(AST_INTERFACEPORTTYPE));
+		astbuf1->children[0]->str = *$1;
+		delete $1;
+	} TOK_ID {  /* SV interfaces */
+		if (!sv_mode)
+			frontend_verilog_yyerror("Interface found in port list (%s). This is not supported unless read_verilog is called with -sv!", $3->c_str());
+		astbuf2 = astbuf1->clone(); // really only needed if multiple instances of same type.
+		astbuf2->str = *$3;
+		delete $3;
+		astbuf2->port_id = ++port_counter;
+		ast_stack.back()->children.push_back(astbuf2);
+		delete astbuf1; // really only needed if multiple instances of same type.
+	} module_arg_opt_assignment |
 	attr wire_type range TOK_ID {
 		AstNode *node = $2;
 		node->str = *$4;
@@ -357,6 +374,33 @@ package_body:
 package_body_stmt:
 	localparam_decl;
 
+interface:
+	TOK_INTERFACE TOK_ID {
+		do_not_require_port_stubs = false;
+		AstNode *intf = new AstNode(AST_INTERFACE);
+		ast_stack.back()->children.push_back(intf);
+		ast_stack.push_back(intf);
+		current_ast_mod = intf;
+		port_stubs.clear();
+		port_counter = 0;
+		intf->str = *$2;
+		delete $2;
+	} module_para_opt module_args_opt ';' interface_body TOK_ENDINTERFACE {
+		if (port_stubs.size() != 0)
+			frontend_verilog_yyerror("Missing details for module port `%s'.",
+				port_stubs.begin()->first.c_str());
+		ast_stack.pop_back();
+		log_assert(ast_stack.size() == 1);
+		current_ast_mod = NULL;
+	};
+
+interface_body:
+	interface_body interface_body_stmt |;
+
+interface_body_stmt:
+	param_decl | localparam_decl | defparam_decl | wire_decl | always_stmt | assign_stmt |
+	modport_stmt;
+
 non_opt_delay:
 	'#' TOK_ID { delete $2; } |
 	'#' TOK_CONSTVAL { delete $2; } |
@@ -1280,6 +1324,22 @@ opt_property:
 opt_stmt_label:
 	TOK_ID ':' | /* empty */;
 
+modport_stmt:
+    TOK_MODPORT TOK_ID modport_args_opt ';'
+
+modport_args_opt:
+    '(' ')' | '(' modport_args optional_comma ')';
+
+modport_args:
+    modport_arg | modport_args ',' modport_arg;
+
+modport_arg:
+    modport_type_token TOK_ID |
+    TOK_ID
+
+modport_type_token:
+    TOK_INPUT | TOK_OUTPUT
+
 assert:
 	opt_stmt_label TOK_ASSERT opt_property '(' expr ')' ';' {
 		if (noassert_mode)