system.v

   1 `define BUS_ICACHE 0
   2
   3 module System(input clk, output wire bubbleshield, output wire [31:0] insn, output wire [31:0] pc);
   4         wire [7:0] bus_req;
   5         wire [7:0] bus_ack;
   6         wire [31:0] bus_addr;
   7         wire [31:0] bus_rdata;
   8         wire [31:0] bus_wdata;
   9         wire bus_rd, bus_wr;
  10         wire bus_ready;
  11
  12         wire bus_req_icache;
  13         assign bus_req = {7'b0, bus_req_icache};
  14         wire bus_ack_icache = bus_ack[`BUS_ICACHE];
  15
  16         wire [31:0] bus_addr_icache;
  17         wire [31:0] bus_wdata_icache;
  18         wire bus_rd_icache;
  19         wire bus_wr_icache;
  20
  21         wire [31:0] bus_rdata_blockram;
  22         wire bus_ready_blockram;
  23
  24         assign bus_addr = bus_addr_icache;
  25         assign bus_rdata = bus_rdata_blockram;
  26         assign bus_wdata = bus_wdata_icache;
  27         assign bus_rd = bus_rd_icache;
  28         assign bus_wr = bus_wr_icache;
  29         assign bus_ready = bus_ready_blockram;
  30
  31         wire [31:0] icache_rd_addr;
  32         wire icache_rd_req;
  33         wire icache_rd_wait;
  34         wire [31:0] icache_rd_data;
  35
  36         wire stall_cause_issue;
  37
  38         wire stall_in_fetch = stall_cause_issue;
  39         wire stall_in_issue = 0;
  40
  41         wire [31:0] decode_out_op0, decode_out_op1, decode_out_op2;
  42         wire decode_out_carry;
  43         wire [3:0] regfile_read_0, regfile_read_1, regfile_read_2;
  44         wire [31:0] regfile_rdata_0, regfile_rdata_1, regfile_rdata_2;
  45
  46         wire bubble_out_fetch;
  47         wire bubble_out_issue;
  48         wire [31:0] insn_out_fetch;
  49         wire [31:0] insn_out_issue;
  50         wire [31:0] pc_out_fetch;
  51         wire [31:0] pc_out_issue;
  52
  53         assign bubbleshield = bubble_out_issue;
  54         assign insn = insn_out_issue;
  55         assign pc = pc_out_issue;
  56
  57         BusArbiter busarbiter(.bus_req(bus_req), .bus_ack(bus_ack));
  58
  59         ICache icache(
  60                 .clk(clk),
  61                 /* XXX reset? */
  62                 .rd_addr(icache_rd_addr), .rd_req(icache_rd_req),
  63                 .rd_wait(icache_rd_wait), .rd_data(icache_rd_data),
  64                 .bus_req(bus_req_icache), .bus_ack(bus_ack_icache),
  65                 .bus_addr(bus_addr_icache), .bus_rdata(bus_rdata),
  66                 .bus_wdata(bus_wdata_icache), .bus_rd(bus_rd_icache),
  67                 .bus_wr(bus_wr_icache), .bus_ready(bus_ready));
  68
  69         BlockRAM blockram(
  70                 .clk(clk),
  71                 .bus_addr(bus_addr), .bus_rdata(bus_rdata_blockram),
  72                 .bus_wdata(bus_wdata), .bus_rd(bus_rd), .bus_wr(bus_wr),
  73                 .bus_ready(bus_ready_blockram));
  74
  75         Fetch fetch(
  76                 .clk(clk),
  77                 .Nrst(1 /* XXX */),
  78                 .rd_addr(icache_rd_addr), .rd_req(icache_rd_req),
  79                 .rd_wait(icache_rd_wait), .rd_data(icache_rd_data),
  80                 .stall(stall_in_fetch), .jmp(0 /* XXX */), .jmppc(0 /* XXX */),
  81                 .bubble(bubble_out_fetch), .insn(insn_out_fetch),
  82                 .pc(pc_out_fetch));
  83
  84         Issue issue(
  85                 .clk(clk),
  86                 .Nrst(1 /* XXX */),
  87                 .stall(stall_in_issue), .flush(0 /* XXX */),
  88                 .inbubble(bubble_out_fetch), .insn(insn_out_fetch),
  89                 .inpc(pc_out_fetch), .cpsr(0 /* XXX */),
  90                 .outstall(stall_cause_issue), .outbubble(bubble_out_issue),
  91                 .outpc(pc_out_issue), .outinsn(insn_out_issue));
  92
  93         RegFile regfile(
  94                 .clk(clk),
  95                 .read_0(regfile_read_0), .read_1(regfile_read_1), .read_2(regfile_read_2),
  96                 .rdata_0(regfile_rdata_0), .rdata_1(regfile_rdata_1), .rdata_2(regfile_rdata_2),
  97                 .write(0), .write_req(0), .write_data(0 /* XXX */));
  98
  99         Decode decode(
 100                 .clk(clk),
 101                 .insn(insn_out_fetch), .inpc(pc_out_fetch), .incpsr(0 /* XXX */),
 102                 .op0(decode_out_op0), .op1(decode_out_op1), .op2(decode_out_op2),
 103                 .carry(decode_out_carry),
 104                 .read_0(regfile_read_0), .read_1(regfile_read_1), .read_2(regfile_read_2),
 105                 .rdata_0(regfile_rdata_0), .rdata_1(regfile_rdata_1), .rdata_2(regfile_rdata_2));
 106
 107         reg [31:0] clockno = 0;
 108         always @(posedge clk)
 109         begin
 110                 clockno <= clockno + 1;
 111                 $display("------------------------------------------------------------------------------");
 112                 $display("%3d: FETCH:            Bubble: %d, Instruction: %08x, PC: %08x", clockno, bubble_out_fetch, insn_out_fetch, pc_out_fetch);
 113                 $display("%3d: ISSUE:  Stall: %d, Bubble: %d, Instruction: %08x, PC: %08x", clockno, stall_cause_issue, bubble_out_issue, insn_out_issue, pc_out_issue);
 114                 $display("%3d: DECODE:                      op1 %08x, op2 %08x, op3 %08x, carry %d", clockno, decode_out_op0, decode_out_op1, decode_out_op2, decode_out_carry);
 115         end
 116 endmodule