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Move RF address decoding to serv_immdec

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Olof Kindgren
2020-08-17 13:00:29 +02:00
parent 58e86384e7
commit 915cdf7933
4 changed files with 22 additions and 19 deletions
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11
rtl/serv_decode.v
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@@ -33,10 +33,6 @@ module serv_decode
output wire o_alu_sh_signed,
output wire o_alu_sh_right,
output wire [3:0] o_alu_rd_sel,
//To RF
output reg [4:0] o_rf_rd_addr,
output reg [4:0] o_rf_rs1_addr,
output reg [4:0] o_rf_rs2_addr,
//To mem IF
output wire o_mem_signed,
output wire o_mem_word,
@@ -115,12 +111,12 @@ module serv_decode
//False for STORE, BRANCH, MISC-MEM
assign o_rd_op = (opcode[2] |
(!opcode[2] & opcode[4] & opcode[0]) |
(!opcode[2] & !opcode[3] & !opcode[0])) & (|o_rf_rd_addr);
(!opcode[2] & !opcode[3] & !opcode[0]));
//True for sub, sll*, b*, slt*
//False for add*, sr*
assign o_alu_sub = (!funct3[2] & (funct3[0] | (opcode[3] & imm30))) | funct3[1] | opcode[4];
/*
300 0_000 mstatus RWSC
@@ -183,9 +179,6 @@ module serv_decode
assign o_alu_rd_sel[3] = (funct3[2] & !(funct3[1:0] == 2'b01)); //Bool
always @(posedge clk) begin
if (i_wb_en) begin
o_rf_rd_addr <= i_wb_rdt[11:7];
o_rf_rs1_addr <= i_wb_rdt[19:15];
o_rf_rs2_addr <= i_wb_rdt[24:20];
funct3 <= i_wb_rdt[14:12];
imm30 <= i_wb_rdt[30];
opcode <= i_wb_rdt[6:2];