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Fix jump_in_id signal should only be set in DECODE in controller

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Sven Stucki 2015-08-26 15:22:49 +02:00
parent 08b2be2b76
commit 8bdb45799f
1 changed files with 14 additions and 12 deletions
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26
controller.sv
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@ -157,6 +157,7 @@ module controller
logic regfile_alu_we;
logic data_we;
logic data_req;
logic [1:0] jump_in_id;
logic deassert_we;
logic lsu_stall;
@ -187,7 +188,7 @@ module controller
always_comb
begin
// Default values
jump_in_id_o = `BRANCH_NONE;
jump_in_id = `BRANCH_NONE;
alu_operator = `ALU_NOP;
extend_immediate_o = 1'b0;
@ -254,7 +255,7 @@ module controller
`OPCODE_JAL: begin // Jump and Link
if (instr_rdata_i ==? `INSTR_JAL) begin
// Insert bubbles
jump_in_id_o = `BRANCH_JAL;
jump_in_id = `BRANCH_JAL;
// Calculate and store PC+4
alu_op_a_mux_sel_o = `OP_A_CURRPC;
alu_op_b_mux_sel_o = `OP_B_IMM;
@ -271,7 +272,7 @@ module controller
`OPCODE_JALR: begin // Jump and Link Register
if (instr_rdata_i ==? `INSTR_JALR) begin
// Insert bubbles
jump_in_id_o = `BRANCH_JALR;
jump_in_id = `BRANCH_JALR;
// Calculate and store PC+4
alu_op_a_mux_sel_o = `OP_A_CURRPC;
alu_op_b_mux_sel_o = `OP_B_IMM;
@ -287,7 +288,7 @@ module controller
end
`OPCODE_BRANCH: begin // Branch
jump_in_id_o = `BRANCH_COND;
jump_in_id = `BRANCH_COND;
alu_op_c_mux_sel_o = `OP_C_JT;
rega_used = 1'b1;
regb_used = 1'b1;
@ -1075,7 +1076,7 @@ module controller
DECODE:
begin
if (jump_in_id_o != `BRANCH_NONE) begin
if (jump_in_id != `BRANCH_NONE) begin
// handle branch if decision is availble in next cycle
if (~stall_id_o)
ctrl_fsm_ns = BRANCH;
@ -1096,7 +1097,7 @@ module controller
// branches take two cycles, jumps just one
// everything else can be done immediately
// TODO: there is a bug here, I'm sure of it
if(trap_hit_i == 1'b1 && stall_ex_o == 1'b0 && jump_in_id_o == 2'b0 && jump_in_ex_i == 2'b0)
if(trap_hit_i == 1'b1 && stall_ex_o == 1'b0 && jump_in_id == 2'b0 && jump_in_ex_i == 2'b0)
begin
dbg_halt = 1'b1;
ctrl_fsm_ns = DBG_FLUSH_EX;
@ -1209,12 +1210,13 @@ module controller
assign trap_stall = trap_insn_o;
// deassert we signals (in case of stalls)
assign alu_operator_o = (deassert_we) ? `ALU_NOP : alu_operator;
assign mult_en_o = (deassert_we) ? 1'b0 : mult_en;
assign regfile_we_o = (deassert_we) ? 1'b0 : regfile_we;
assign regfile_alu_we_o = (deassert_we) ? 1'b0 : regfile_alu_we;
assign data_we_o = (deassert_we) ? 1'b0 : data_we;
assign data_req_o = (deassert_we) ? 1'b0 : data_req;
assign alu_operator_o = (deassert_we) ? `ALU_NOP : alu_operator;
assign mult_en_o = (deassert_we) ? 1'b0 : mult_en;
assign regfile_we_o = (deassert_we) ? 1'b0 : regfile_we;
assign regfile_alu_we_o = (deassert_we) ? 1'b0 : regfile_alu_we;
assign data_we_o = (deassert_we) ? 1'b0 : data_we;
assign data_req_o = (deassert_we) ? 1'b0 : data_req;
assign jump_in_id_o = (deassert_we) ? `BRANCH_NONE : jump_in_id;
// TODO: Remove? Can be replaced with stall.