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Code Issues Releases Wiki Activity

Simplify optional MDU logic

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This commit is contained in:
Olof Kindgren
2021-10-03 23:28:45 +02:00
parent 8843005407
commit 99f82af6eb
3 changed files with 16 additions and 55 deletions
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33
rtl/serv_decode.v
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@@ -1,5 +1,5 @@
`default_nettype none
module serv_decode
module serv_decode
#(parameter [0:0] PRE_REGISTER = 1,
parameter [0:0] MDU = 0)
(
@@ -69,35 +69,16 @@ module serv_decode
reg imm25;
reg imm30;
generate
wire co_mdu_op;
wire [2:0]co_ext_funct3;
wire co_shift_op;
wire co_slt_op;
wire co_mem_word;
wire co_rd_alu_en;
//opcode
wire op_or_opimm = (!opcode[4] & opcode[2] & !opcode[0]);
wire co_mdu_op = MDU & (opcode == 5'b01100) & imm25;
wire co_shift_op = op_or_opimm & (funct3[1:0] == 2'b01) & !co_mdu_op;
wire co_slt_op = op_or_opimm & (funct3[2:1] == 2'b01) & !co_mdu_op;
wire co_mem_op = !opcode[4] & !opcode[2] & !opcode[0];
wire co_branch_op = opcode[4] & !opcode[2];
if (MDU) begin
assign co_mdu_op = ((opcode == 5'b01100) & imm25);
assign co_shift_op = op_or_opimm & (funct3[1:0] == 2'b01) & !co_mdu_op;
assign co_slt_op = op_or_opimm & (funct3[2:1] == 2'b01) & !co_mdu_op;
assign co_mem_word = co_mdu_op ? co_mdu_op :funct3[1];
assign co_rd_alu_en = !opcode[0] & opcode[2] & !opcode[4] & !co_mdu_op;
end else begin
assign co_mdu_op = 1'b0;
assign co_shift_op = op_or_opimm & (funct3[1:0] == 2'b01);
assign co_slt_op = op_or_opimm & (funct3[2:1] == 2'b01);
assign co_mem_word = funct3[1];
assign co_rd_alu_en = !opcode[0] & opcode[2] & !opcode[4];
end
assign co_ext_funct3 = funct3;
endgenerate
wire co_mem_word = co_mdu_op | funct3[1];
wire co_rd_alu_en = !opcode[0] & opcode[2] & !opcode[4] & !co_mdu_op;
wire [2:0] co_ext_funct3 = funct3;
//jal,branch = imm
//jalr = rs1+imm