Support w=4 in serv_ctrl

rtl/serv_ctrl.v

@@ -2,7 +2,10 @@
 module serv_ctrl
   #(parameter RESET_STRATEGY = "MINI",
     parameter RESET_PC = 32'd0,
-    parameter WITH_CSR = 1)
+    parameter WITH_CSR = 1,
+    parameter W = 1,
+    parameter B = W-1
+  )
   (
    input wire 	     clk,
    input wire 	     i_rst,
@@ -20,52 +23,74 @@ module serv_ctrl
    input wire 	     i_trap,
    input wire        i_iscomp,
    //Data
-   input wire 	     i_imm,
-   input wire 	     i_buf,
-   input wire 	     i_csr_pc,
-   output wire 	     o_rd,
-   output wire 	     o_bad_pc,
+   input wire [B:0] i_imm,
+   input wire [B:0] i_buf,
+   input wire [B:0] i_csr_pc,
+   output wire [B:0] o_rd,
+   output wire [B:0] o_bad_pc,
    //External
    output reg [31:0] o_ibus_adr);
 
-   wire       pc_plus_4;
+   wire [B:0] pc_plus_4;
    wire       pc_plus_4_cy;
    reg 	      pc_plus_4_cy_r;
-   wire       pc_plus_offset;
+   wire [B:0] pc_plus_4_cy_r_w;
+   wire [B:0] pc_plus_offset;
    wire       pc_plus_offset_cy;
-   reg 	      pc_plus_offset_cy_r;
-   wire       pc_plus_offset_aligned;
-   wire       plus_4;
+   reg	      pc_plus_offset_cy_r;
+   wire [B:0] pc_plus_offset_cy_r_w;
+   wire [B:0] pc_plus_offset_aligned;
+   wire [B:0] plus_4;
 
-   wire       pc = o_ibus_adr[0];
+   wire [B:0] pc = o_ibus_adr[B:0];
 
-   wire       new_pc;
+   wire [B:0] new_pc;
 
-   wire       offset_a;
-   wire       offset_b;
+   wire [B:0] offset_a;
+   wire [B:0] offset_b;
 
   /*  If i_iscomp=1: increment pc by 2 else increment pc by 4  */
 
-   assign plus_4        = i_iscomp ? i_cnt1 : i_cnt2;
+   generate
+      if (W == 1) begin : gen_plus_4_w_eq_1
+	 assign plus_4 = i_iscomp ? i_cnt1 : i_cnt2;
+      end else if (W == 4) begin : gen_plus_4_w_eq_4
+	 assign plus_4 = (i_cnt0 | i_cnt1) ? (i_iscomp ? 2 : 4) : 0;
+      end
+   endgenerate
 
    assign o_bad_pc = pc_plus_offset_aligned;
 
-   assign {pc_plus_4_cy,pc_plus_4} = pc+plus_4+pc_plus_4_cy_r;
+   assign {pc_plus_4_cy,pc_plus_4} = pc+plus_4+pc_plus_4_cy_r_w;
 
    generate
       if (|WITH_CSR) begin : gen_csr
-	 assign new_pc = i_trap ? (i_csr_pc & !i_cnt0) : i_jump ? pc_plus_offset_aligned : pc_plus_4;
+	 if (W == 1) begin : gen_new_pc_w_eq_1
+	    assign new_pc = i_trap ? (i_csr_pc & !(i_cnt0 || i_cnt1)) : i_jump ? pc_plus_offset_aligned : pc_plus_4;
+         end else if (W == 4) begin : gen_new_pc_w_eq_4
+	    assign new_pc = i_trap ? (i_csr_pc & ((i_cnt0 || i_cnt1) ? 4'b1100 : 4'b1111)) : i_jump ? pc_plus_offset_aligned : pc_plus_4;
+	 end
       end else begin : gen_no_csr
 	 assign new_pc = i_jump ? pc_plus_offset_aligned : pc_plus_4;
       end
    endgenerate
-   assign o_rd  = (i_utype & pc_plus_offset_aligned) | (pc_plus_4 & i_jal_or_jalr);
+   assign o_rd  = ({W{i_utype}} & pc_plus_offset_aligned) | (pc_plus_4 & {W{i_jal_or_jalr}});
+
+   assign offset_a = {W{i_pc_rel}} & pc;
+   assign offset_b = i_utype ? (i_imm & {W{i_cnt12to31}}) : i_buf;
+   assign {pc_plus_offset_cy,pc_plus_offset} = offset_a+offset_b+pc_plus_offset_cy_r_w;
 
-   assign offset_a = i_pc_rel & pc;
-   assign offset_b = i_utype ? (i_imm & i_cnt12to31): i_buf;
-   assign {pc_plus_offset_cy,pc_plus_offset} = offset_a+offset_b+pc_plus_offset_cy_r;
+   generate
+   if (W>1) begin : gen_w_gt_1
+	 assign pc_plus_offset_aligned[B:1] = pc_plus_offset[B:1];
+	 assign pc_plus_offset_cy_r_w[B:1] = {B{1'b0}};
+	 assign pc_plus_4_cy_r_w[B:1] = {B{1'b0}};
+   end
+   endgenerate
 
-   assign pc_plus_offset_aligned = pc_plus_offset & !i_cnt0;
+   assign pc_plus_offset_aligned[0] = pc_plus_offset[0] & !i_cnt0;
+   assign pc_plus_offset_cy_r_w[0] = pc_plus_offset_cy_r;
+   assign pc_plus_4_cy_r_w[0] = pc_plus_4_cy_r;
 
    initial if (RESET_STRATEGY == "NONE") o_ibus_adr = RESET_PC;
 
@@ -75,10 +100,10 @@ module serv_ctrl
 
       if (RESET_STRATEGY == "NONE") begin
 	 if (i_pc_en)
-	   o_ibus_adr <= {new_pc, o_ibus_adr[31:1]};
+	   o_ibus_adr <= {new_pc, o_ibus_adr[31:W]};
       end else begin
 	 if (i_pc_en | i_rst)
-	   o_ibus_adr <= i_rst ? RESET_PC : {new_pc, o_ibus_adr[31:1]};
+	   o_ibus_adr <= i_rst ? RESET_PC : {new_pc, o_ibus_adr[31:W]};
       end
    end
 endmodule