output reg [31:0] out_write_data = 32'hxxxxxxxx
);
- reg [31:0] addr, raddr;
- reg next_notdone, next_inc_next;
+ reg [31:0] addr, raddr, next_regdata;
+ reg [3:0] next_regsel, cur_reg, prev_reg;
+ reg next_writeback, next_notdone, next_inc_next;
reg [31:0] align_s1, align_s2, align_rddata;
+ wire next_outbubble;
wire next_write_reg;
wire [3:0] next_write_num;
wire [31:0] next_write_data;
reg [15:0] regs, next_regs;
+ reg started = 1'b0, next_started;
reg notdone = 1'b0;
reg inc_next = 1'b0;
begin
outpc <= pc;
outinsn <= insn;
- outbubble <= rw_wait;
- out_write_reg <= next_writeback;
- out_write_num <= next_regsel;
- out_write_data <= next_regdata;
+ outbubble <= next_outbubble;
+ out_write_reg <= next_write_reg;
+ out_write_num <= next_write_num;
+ out_write_data <= next_write_data;
notdone <= next_notdone;
inc_next <= next_inc_next;
regs <= next_regs;
+ prev_reg <= cur_reg;
+ started <= next_started;
end
always @(*)
next_write_num = write_num;
next_write_data = write_data;
next_inc_next = 1'b0;
+ next_outbubble = inbubble;
outstall = 1'b0;
-
+ next_regs = 16'b0;
+ next_started = started;
+
casez(insn)
`DECODE_LDRSTR_UNDEFINED: begin end
`DECODE_LDRSTR: begin
if (!inbubble) begin
+ next_outbubble = rw_wait;
outstall = rw_wait | notdone;
addr = insn[23] ? op0 + op1 : op0 - op1; /* up/down select */
end
end
`DECODE_LDMSTM: begin
- busaddr = {op0[31:2], 2'b0};
rd_req = insn[20];
wr_req = ~insn[20];
- casez(regs)
- 16'b???????????????1: begin
- next_regs = regs;
- end
- 16'b??????????????10: begin
- end
- 16'b?????????????100: begin
- end
- 16'b????????????1000: begin
- end
- 16'b???????????10000: begin
- end
- 16'b??????????100000: begin
- end
- 16'b?????????1000000: begin
- end
- 16'b????????10000000: begin
+ if(!started) begin
+ next_regs = op1[15:0];
+ next_started = 1'b1;
end
- 16'b???????100000000: begin
- end
- 16'b??????1000000000: begin
- end
- 16'b?????10000000000: begin
- end
- 16'b????100000000000: begin
- end
- 16'b???1000000000000: begin
- end
- 16'b??10000000000000: begin
- end
- 16'b?100000000000000: begin
+ else if(inc_next) begin
+ if(insn[21]) begin
+ next_write_reg = 1'b1;
+ next_write_num = insn[19:16];
+ next_write_data = op0;
+ end
+ next_started = 1'b0;
end
- 16'b1000000000000000: begin
+ else if(rw_wait) begin
+ next_regs = regs;
+ cur_reg = prev_reg;
end
- default: begin
- next_inc_next = 1'b1;
+ else begin
+ casez(regs)
+ 16'b???????????????1: begin
+ cur_reg = 4'h0;
+ next_regs = regs & 16'b1111111111111110;
+ end
+ 16'b??????????????10: begin
+ cur_reg = 4'h1;
+ next_regs = regs & 16'b1111111111111100;
+ end
+ 16'b?????????????100: begin
+ cur_reg = 4'h2;
+ next_regs = regs & 16'b1111111111111000;
+ end
+ 16'b????????????1000: begin
+ cur_reg = 4'h3;
+ next_regs = regs & 16'b1111111111110000;
+ end
+ 16'b???????????10000: begin
+ cur_reg = 4'h4;
+ next_regs = regs & 16'b1111111111100000;
+ end
+ 16'b??????????100000: begin
+ cur_reg = 4'h5;
+ next_regs = regs & 16'b1111111111000000;
+ end
+ 16'b?????????1000000: begin
+ cur_reg = 4'h6;
+ next_regs = regs & 16'b1111111110000000;
+ end
+ 16'b????????10000000: begin
+ cur_reg = 4'h7;
+ next_regs = regs & 16'b1111111100000000;
+ end
+ 16'b???????100000000: begin
+ cur_reg = 4'h8;
+ next_regs = regs & 16'b1111111000000000;
+ end
+ 16'b??????1000000000: begin
+ cur_reg = 4'h9;
+ next_regs = regs & 16'b1111110000000000;
+ end
+ 16'b?????10000000000: begin
+ cur_reg = 4'hA;
+ next_regs = regs & 16'b1111100000000000;
+ end
+ 16'b????100000000000: begin
+ cur_reg = 4'hB;
+ next_regs = regs & 16'b1111000000000000;
+ end
+ 16'b???1000000000000: begin
+ cur_reg = 4'hC;
+ next_regs = regs & 16'b1110000000000000;
+ end
+ 16'b??10000000000000: begin
+ cur_reg = 4'hD;
+ next_regs = regs & 16'b1100000000000000;
+ end
+ 16'b?100000000000000: begin
+ cur_reg = 4'hE;
+ next_regs = regs & 16'b1000000000000000;
+ end
+ 16'b1000000000000000: begin
+ cur_reg = 4'hF;
+ next_regs = 16'b0;
+ end
+ default: begin
+ cur_reg = 4'hx;
+ next_regs = 16'b0;
+ end
+ endcase
+ next_inc_next = next_regs == 16'b0;
+ next_notdone = ~next_inc_next | (rw_wait & insn[20] & insn[21]);
end
- endcase
end
default: begin end
endcase