+Added icache stage -- 3rd case of AUIPC os broken?

rtl/VX_fetch.v

@@ -7,26 +7,39 @@ module VX_fetch (
 	VX_wstall_inter          VX_wstall,
 	VX_join_inter            VX_join,
 	input  wire              schedule_delay,
-	VX_icache_response_inter icache_response,
+	input  wire              icache_stage_delay,
-	VX_icache_request_inter  icache_request,
 
 	output wire              out_ebreak,
 	VX_jal_response_inter    VX_jal_rsp,
 	VX_branch_response_inter VX_branch_rsp,
-	VX_inst_meta_inter       fe_inst_meta_fd,
+	VX_inst_meta_inter       fe_inst_meta_fi,
 	VX_warp_ctl_inter        VX_warp_ctl
 );
 
-		// Locals
-		wire pipe_stall;
-
-
-		assign pipe_stall = schedule_delay || icache_response.delay;
-
 		wire[`NT_M1:0] thread_mask;
 		wire[`NW_M1:0] warp_num;
 		wire[31:0]     warp_pc;
 		wire           scheduled_warp;
+
+
+		// Only reason this is there is because there is a hidden assumption that decode is exactly after fetch
+		reg stall_might_be_branch;
+		always @(posedge clk) begin
+			if (reset) begin
+				stall_might_be_branch <= 0;
+			end else if (stall_might_be_branch == 1'b1) begin
+				stall_might_be_branch <= 0;
+			end else if (scheduled_warp == 1'b1) begin
+				stall_might_be_branch <= 1'b1;
+			end
+		end
+
+		// Locals
+		wire pipe_stall;
+
+
+		assign pipe_stall = schedule_delay || icache_stage_delay || stall_might_be_branch;
+
 		VX_warp_scheduler warp_scheduler(
 			.clk              (clk),
 			.reset            (reset),
@@ -83,21 +96,10 @@ module VX_fetch (
 			.scheduled_warp   (scheduled_warp)
 			);
 
-		// always @(*) begin
+		assign fe_inst_meta_fi.warp_num  = warp_num;
-		// 	$display("Inside verilog instr: %h, pc: %h", icache_response.instruction, warp_pc);
+		assign fe_inst_meta_fi.valid     = thread_mask;
-		// end
 
-		assign icache_request.pc_address 						= warp_pc;
+		assign fe_inst_meta_fi.inst_pc     = warp_pc;
-		assign icache_request.out_cache_driver_in_valid 		= !schedule_delay && scheduled_warp;
-		assign icache_request.out_cache_driver_in_mem_read		= `LW_MEM_READ;
-		assign icache_request.out_cache_driver_in_mem_write		= `NO_MEM_WRITE;
-	  	assign icache_request.out_cache_driver_in_data			= 32'b0;
-
-		assign fe_inst_meta_fd.warp_num  = warp_num;
-		assign fe_inst_meta_fd.valid     = thread_mask;
-
-		assign fe_inst_meta_fd.instruction = (thread_mask == 0) ? 32'b0 : icache_response.instruction;
-		assign fe_inst_meta_fd.inst_pc     = warp_pc;
 
 
 endmodule

rtl/VX_front_end.v

@@ -20,12 +20,15 @@ module VX_front_end (
 );
 
 
-VX_inst_meta_inter        fe_inst_meta_fd();
+VX_inst_meta_inter        fe_inst_meta_fi();
+VX_inst_meta_inter        fe_inst_meta_fi2();
+VX_inst_meta_inter        fe_inst_meta_id();
 
 VX_frE_to_bckE_req_inter VX_frE_to_bckE_req();
 VX_inst_meta_inter       fd_inst_meta_de();
 
 wire total_freeze = schedule_delay;
+wire icache_stage_delay;
 
 /* verilator lint_off UNUSED */
 // wire real_fetch_ebreak;
@@ -47,20 +50,38 @@ VX_fetch vx_fetch(
 		.VX_join            (VX_join),
 		.schedule_delay     (schedule_delay),
 		.VX_jal_rsp         (VX_jal_rsp),
-		.icache_response    (icache_response_fe),
 		.VX_warp_ctl        (VX_warp_ctl),
-
+		.icache_stage_delay (icache_stage_delay),
-		.icache_request     (icache_request_fe),
 		.VX_branch_rsp      (VX_branch_rsp),
 		.out_ebreak         (vortex_ebreak), // fetch_ebreak
-		.fe_inst_meta_fd    (fe_inst_meta_fd)
+		.fe_inst_meta_fi    (fe_inst_meta_fi)
 	);
 
-VX_f_d_reg vx_f_d_reg(
+wire freeze_fi_reg = total_freeze || icache_stage_delay;
+VX_f_d_reg vx_f_i_reg(
+		.clk            (clk),
+		.reset          (reset),
+		.in_freeze      (freeze_fi_reg),
+		.fe_inst_meta_fd(fe_inst_meta_fi),
+		.fd_inst_meta_de(fe_inst_meta_fi2)
+	);
+
+VX_icache_stage VX_icache_stage(
+	.clk               (clk),
+	.reset             (reset),
+	.icache_stage_delay(icache_stage_delay),
+	.fe_inst_meta_fi   (fe_inst_meta_fi2),
+	.fe_inst_meta_id   (fe_inst_meta_id),
+	.icache_response   (icache_response_fe),
+	.icache_request    (icache_request_fe)
+	);
+
+
+VX_f_d_reg vx_i_d_reg(
 		.clk            (clk),
 		.reset          (reset),
 		.in_freeze      (total_freeze),
-		.fe_inst_meta_fd(fe_inst_meta_fd),
+		.fe_inst_meta_fd(fe_inst_meta_id),
 		.fd_inst_meta_de(fd_inst_meta_de)
 	);
 

rtl/VX_icache_stage.v

@@ -0,0 +1,31 @@
+`include "VX_define.v"
+
+module VX_icache_stage (
+	input  wire              clk,
+	input  wire              reset,
+	output wire              icache_stage_delay,
+	VX_inst_meta_inter       fe_inst_meta_fi,
+	VX_inst_meta_inter       fe_inst_meta_id,
+	VX_icache_response_inter icache_response,
+	VX_icache_request_inter  icache_request
+);
+
+		wire   valid_inst = (|fe_inst_meta_fi.valid);
+
+		assign icache_request.pc_address 						= fe_inst_meta_fi.inst_pc;
+		assign icache_request.out_cache_driver_in_valid 		= fe_inst_meta_fi.valid != 0;
+		assign icache_request.out_cache_driver_in_mem_read		= `LW_MEM_READ;
+		assign icache_request.out_cache_driver_in_mem_write		= `NO_MEM_WRITE;
+	  	assign icache_request.out_cache_driver_in_data			= 32'b0;
+
+
+
+	  	assign icache_stage_delay = icache_response.delay;
+
+		assign fe_inst_meta_id.instruction = (!valid_inst || icache_response.delay) ? 32'b0 : icache_response.instruction;
+		assign fe_inst_meta_id.inst_pc     = fe_inst_meta_fi.inst_pc;
+		assign fe_inst_meta_id.warp_num    = fe_inst_meta_fi.warp_num;
+		assign fe_inst_meta_id.valid       = fe_inst_meta_fi.valid;
+
+
+endmodule

rtl/simulate/test_bench.cpp

@@ -67,14 +67,19 @@ int main(int argc, char **argv)
     for (std::string s : tests) {
         Vortex v;
 
+        std::cerr << DEFAULT << "\n---------------------------------------\n";
+
         std::cerr << s << std::endl;
 
         bool curr = v.simulate(s);
         if ( curr) std::cerr << GREEN << "Test Passed: " << s << std::endl;
         if (!curr) std::cerr << RED   << "Test Failed: " << s << std::endl;
+        std::cerr << DEFAULT;
         passed = passed && curr;
     }
 
+    std::cerr << DEFAULT << "\n***************************************\n";
+
     if( passed) std::cerr << DEFAULT << "PASSED ALL TESTS\n";
 	if(!passed) std::cerr << DEFAULT << "Failed one or more tests\n";
 
@@ -82,15 +87,15 @@ int main(int argc, char **argv)
 
 	#else
 
-	char testing[] = "../../emulator/riscv_tests/rv32ui-p-sw.hex";
+	char testing[] = "../../emulator/riscv_tests/rv32ui-p-auipc.hex";
 	Vortex v;
-	const char *testing;
+	// const char *testing;
 
-	if (argc >= 2) {
+	// if (argc >= 2) {
-	    testing = argv[1];
+	//     testing = argv[1];
-	} else {
+	// } else {
-	    testing = "../../kernel/vortex_test.hex";
+	//     testing = "../../kernel/vortex_test.hex";
-	}
+	// }
 
     std::cerr << testing << std::endl;