该文是基于博主之前一篇博客http://www.cnblogs.com/wsine/p/4292869.html所增加的Hazard处理,相同的内容就不重复写了,可点击链接查看之前的博客。
该处理器的五级流水线设计:
类似于MIPS体系架构依据流水线结构设计。只要CPU从缓存中获取数据,那么执行每条MIPS指令就被分成五个流水阶段,并且每个阶段占用固定的时间,通常是只耗费一个处理器时钟周期。
处理器在设计时,将处理器的执行阶段划分为以下五个阶段:
该CPU用到的指令集,16位8个通用寄存器
该CPU的全部指令一览
该CPU的系统框图
时序逻辑,表示CPU当前状态,有两个枚举值exec和idle,分别是正在运行和空闲两种状态
时序逻辑,每一个上升沿从Instruction Memory中根据地址pc取出一条指令,LOAD指令需要根据不同的指令从当前CPU运算中特定位置读取;Branch指令及其标志位为true则Flush掉一条指令;跳转指令则直接跳转并处理pc值延后一个周期的情况,其余情况直接读取下一条指令
时序逻辑,根据不同的指令,从通用寄存器中取出相应的值出来作运算或者存储到Data Memory中;如果为Branch指令且标志位为true则需要Flush掉当前内容;否则如果冲突出现,则需要根据不同的运算指令从不同的地方取出内容
时序逻辑,根据不同的运算指令作不同的运算;如果为存储指令则直接转移到下一级寄存器,并将写入指令标记为true;如果为其余指令,则保持当前内容不变
组合逻辑,根据不同的指令进行不同的运算,得注意SLA和SRA两条指令在verilog里面的做法。同时注意进位操作的处理。详细看代码。
时序逻辑,只有当LOAD指令需要从Data Memory里面取出内容,其余情况把reg_C传递给reg_C1即可。cf进位标志在此阶段更新。
时序逻辑,对需要写回到寄存器的指令把运算结果写回到寄存器中,其余情况只需让寄存器保持不变
组合逻辑,根据地址的读入,输出一条指令
读取Data是组合逻辑,根据地址直接读取一条指令输出。
写入Data是时序逻辑,每一个周期可能会进行一次写入,根据dw信号进行写入,Memory的时钟频率需要比CPU的时钟快。
Testbench内容
在test中,通过每隔5个ns,时钟取反一次,CPU从button每20个ns进行一次反转即时钟周期为20ns,Memory时钟的设置为三个clk即15个ns反转一次,通过输出用到的通用寄存器和用到的data memory里面的变量来观察整个CPU的流程结果,测试CPU是否正确工作。以及观察仿真流程的变化过程测试CPU是否正常工作。
Instruction Memory:
下面结果用16进制表示,括号内为10进制
指令0:gr1原本初始化时为0,把gr1加上一个立即数AB,gr1为00AB
指令1:gr2原本初始化时为0,把gr2加上一个高八位3C,gr2为3C00
指令2:从gr1和gr2中取值相加,结果保存在gr3中,gr3应为3CAB
指令3:把gr3的值保存到data memory中的dm0,dm0为3CAB
指令4:gr1的值为00AB,加上一个立即数11,gr1为00BC
指令5:gr2的值为3C00,加上一个高八位立即数11,gr2为4D00
指令6:从gr1和gr2中取值相加,结果保存在gr3中,gr3应为4DBC
指令7:把gr3的值保存到data memory中的dm1,dm1为4DBC
指令8:从dm0中取值到gr1中,gr1为3CAB
指令9:从dm1中取值到gr2中,gr2为4DBC
指令10:从gr2和gr1中取值相减,结果保存在gr3中,gr3应为1111
指令11:把gr3的值保存到data memory中的dm2,dm2为1111
指令12:跳转指令,PC跳转到第16条指令
指令13:该指令不被执行,如gr1中出现3D55则出错
指令14:该指令不被执行,如gr1中出现3D55则出错
指令15:该指令不被执行,如gr1中出现3D55则出错
指令16:gr4原本初始化时为0,把gr4加上一个立即数14,gr4为0014(20)
指令17:CMP指令让两个相同的值相减让标志位 zf = 1
指令18:zf = 1, 跳转到gr4 + 2 = 22的指令
指令19:该指令不被执行,如gr1中出现3C83则出错
指令20:该指令不被执行,如gr1中出现3C83则出错
指令21:该指令不被执行,如gr1中出现3C83则出错
指令22:立即数加法,gr1 + AA = 3D55,测试跳转后流水线继续正常工作
指令23:CMP指令让一个小的数值减去一个大的数值,让标志位 nf = 1
指令24:nf = 1, 不跳转 !
指令25:立即数减法,对象是gr1,gr1 – AA = 3CAB
指令26:立即数加法,对象是gr1,gr1 + AA = 3D55
指令27:立即数减法,对象是gr1,gr1 – AA = 3CAB
指令28:空白指令,仅仅是留空,验收时补充指令用的
指令29:空白指令,仅仅是留空,验收时补充指令用的
指令30:跳转指令至40
指令40:终止指令
仿真结果
结果分析
由于是基于上一篇博客的5级流水线的基础上加入Hazard冲突处理,因此这次没有测试各条指令的运算结果是否正确,运算结果的正确性在上一篇博客中已经保证了。这次的测试内容是Data Hazard, Control Hazard, Stall, Branch true, Branch false, halt全部会产生Hazard的情况,结果和预期结果相符。
补充说明:
结果中出现两个PC = 6,三个PC = 10,两个PC = 16的情况,是由于ISE中的检测机制$monitor函数产生的,只要有值变化就会多输出一条,由于Memory的时钟频率比CPU的时钟频率高,因此Memory的变化先于CPU里面的,所以多输出一条,后面的情况类似。实际情况为一个PC = 6,两个PC = 10,一个PC = 16,其中两个PC = 10的情况是LOAD指令产生的Stall,这是正确的。附仿真波形图(较难看清):
三个实用测试
一些感言
刚开始做的时候对Hazard的情况不是很理解,原本以为只需要判断指令的操作数域是否发生冲突就算做完Data Hazard的冲突处理,就像PPT上面的图指示的一样。
但是自己开始做了之后就发现并不是这样的,指令的类型很多,例如运算指令,比较指令,分支指令,跳转指令,存储指令,读取指令,单纯判断操作数域的冲突是不足以判断是否产生Hazard的,因为有些指令时立即数也可能和gr寄存器的编号相同。所以需要连同op域一同比较。
个人对Hazard的理解是,指令都是每一个时钟周期下来流水线往前流动一级,但是一次完整的周期包括读取指令、判断指令、运算指令、存储指令、回写指令这五个周期。Data Hazard是指前一周期的指令还没到达WB回写寄存器这一阶段,后一周期就需要在ID判断指令阶段读取相应寄存器,因此需要把Data Forwarding操作,也就是优先把运算完成的内容取出来;Stall是针对LOAD指令的特殊操作,LOAD只能在MEM阶段才能得到相应的内容,如果下一周期的指令想要Data是不能Forwarding得到的,只能通过延后一周期才能配合Data Forwarding得到相应的内容;Flush是指分支和跳转指令需要到达EX阶段才能知道标志位Flag的判断是否应该跳转,如果需要跳转,则需要把后两个周期读进来的指令冲掉,否则会对结果有无关的影响;如果不需要Flush,则流水线继续往前流动即可。
CPU.v
`timescale 1ns / 1ps
module CPU(
input clk,
input enable,
input reset,
input [3:0] SW,
input start,
input button,
output [6:0] light,
output [3:0] en
);
wire PCPU_clk;
wire MEM_clk;
wire LIGHT_clk;
wire [15:0] d_datain;
wire [15:0] i_datain;
wire [3:0] select_y;
wire [7:0] d_addr;
wire [15:0] d_dataout;
wire d_we;
wire [7:0] i_addr;
wire [15:0] y;
clk_div getMEMclk(
.orgin_clk(clk),
.reset(reset),
//.div(16'b0100_0000_0000_0000),
.div(16'b0000_0000_0000_0001),
.div_clk(MEM_clk)
);
clk_div getLIGHTclk(
.orgin_clk(clk),
.reset(reset),
.div(16'b0010_0000_0000_0000),
.div_clk(LIGHT_clk)
);
PCPUcontroller PCPUctrl(
.myclk(clk),
.button(button),
.reset(reset),
.sense(PCPU_clk)
);
PCPU pcpu(
.clock(PCPU_clk),
.enable(enable),
.reset(reset),
.start(start),
.d_datain(d_datain),
.i_datain(i_datain),
.select_y(SW),
.d_addr(d_addr),
.d_dataout(d_dataout),
.d_we(d_we),
.i_addr(i_addr),
.y(y)
);
I_mem i_mem(
.mem_clk(MEM_clk),
.addr(i_addr),
.rdata(i_datain)
);
D_mem d_mem(
.mem_clk(MEM_clk),
.dwe(d_we),
.addr(d_addr),
.wdata(d_dataout),
.rdata(d_datain)
);
light_show show_light(
.light_clk(LIGHT_clk),
.reset(reset),
.y(y),
.light(light),
.en(en)
);
endmodule
clk_div.v
`timescale 1ns / 1ps
module clk_div(
input orgin_clk,
input reset,
input [15:0] div,
output reg div_clk
);
reg [15:0] count;
always@(posedge orgin_clk or posedge reset)
begin
if(reset)
begin
div_clk <= 0;
count <= 0;
end
else
begin
if(count == div)
begin
div_clk <= ~div_clk;
count <= 0;
end
else
count <= count + 1'b1;
end
end
endmodule
D_mem.v
`timescale 1ns / 1ps
`include"headfile.v"
module D_mem(
input mem_clk,
input dwe,
input [7:0] addr,
input [15:0] wdata,
output wire [15:0] rdata
);
reg [15:0] d_mem [255:0];
assign rdata = d_mem[addr];
always@(posedge mem_clk)
begin
if(dwe)
d_mem[addr] <= wdata;
end
//Test by me
/*initial begin//初始化时全为0
d_mem[0] = 16'b0000000000000000;
d_mem[1] = 16'b0000000000000000;
d_mem[2] = 16'b0000000000000000;
d_mem[3] = 16'b0000000000000000;
d_mem[4] = 16'b0000000000000000;
d_mem[5] = 16'b0000000000000000;
d_mem[6] = 16'b0000000000000000;
d_mem[7] = 16'b0000000000000000;
d_mem[8] = 16'b0000000000000000;
d_mem[9] = 16'b0000000000000000;
d_mem[10] = 16'b0000000000000000;
d_mem[11] = 16'b0000000000000000;
d_mem[12] = 16'b0000000000000000;
d_mem[13] = 16'b0000000000000000;
d_mem[14] = 16'b0000000000000000;
d_mem[15] = 16'b0000000000000000;
d_mem[16] = 16'b0000000000000000;
d_mem[17] = 16'b0000000000000000;
d_mem[18] = 16'b0000000000000000;
d_mem[19] = 16'b0000000000000000;
end*/
// Bubble Test
/*initial begin
d_mem[0] = 16'h000a;
d_mem[1] = 16'h0004;
d_mem[2] = 16'h0005;
d_mem[3] = 16'h2369;
d_mem[4] = 16'h69c3;
d_mem[5] = 16'h0060;
d_mem[6] = 16'h0fff;
d_mem[7] = 16'h5555;
d_mem[8] = 16'h6152;
d_mem[9] = 16'h1057;
d_mem[10] = 16'h2895;
end*/
// GCD Test
/*initial begin
d_mem[0] = 16'h0000;
d_mem[1] = 16'h0020;
d_mem[2] = 16'h0018;
d_mem[3] = 16'h0000;
d_mem[4] = 16'h0000;
d_mem[5] = 16'h0000;
d_mem[6] = 16'h0000;
d_mem[7] = 16'h0000;
d_mem[8] = 16'h0000;
d_mem[9] = 16'h0000;
d_mem[10] = 16'h0000;
end*/
// Sort Test
/*initial begin
d_mem[0] = 16'h000a;
d_mem[1] = 16'h0009;
d_mem[2] = 16'h0006;
d_mem[3] = 16'h0005;
d_mem[4] = 16'h0001;
d_mem[5] = 16'h0004;
d_mem[6] = 16'h0003;
d_mem[7] = 16'h0011;
d_mem[8] = 16'h0000;
d_mem[9] = 16'h0000;
d_mem[10] = 16'h0000;
end*/
// ADD64 Test
initial begin
d_mem[0] <= 16'hfffe;
d_mem[1] <= 16'hfffe;
d_mem[2] <= 16'hfffe;
d_mem[3] <= 16'h0000;
d_mem[4] <= 16'hffff;
d_mem[5] <= 16'hffff;
d_mem[6] <= 16'hffff;
d_mem[7] <= 16'h0000;
d_mem[8] = 16'h0000;
d_mem[9] = 16'h0000;
d_mem[10] = 16'h0000;
end
// Test All
/*initial begin
d_mem[0] <= 16'hfffd;
d_mem[1] <= 16'h0004;
d_mem[2] <= 16'h0005;
d_mem[3] <= 16'hc369;
d_mem[4] <= 16'h69c3;
d_mem[5] <= 16'h0041;
d_mem[6] <= 16'hffff;
d_mem[7] <= 16'h0001;
end*/
endmodule
headfile.v
`ifndef HEADFILE_H_
//State for CPU
`define idle 1'b0
`define exec 1'b1
//Data transfer & Arithmetic
`define NOP 5'b00000
`define HALT 5'b00001
`define LOAD 5'b00010
`define STORE 5'b00011
`define LDIH 5'b10000
`define ADD 5'b01000
`define ADDI 5'b01001
`define ADDC 5'b10001
`define CMP 5'b01100
//Logical / shift
`define AND 5'b01101
`define SLL 5'b00100
`define SLA 5'b00101
//Control
`define JUMP 5'b11000
`define JMPR 5'b11001
`define BZ 5'b11010
`define BNZ 5'b11011
`define BN 5'b11100
`define BC 5'b11110
//Add by myself
`define SUB 5'b01010
`define SUBI 5'b01011
`define SUBC 5'b10010
`define OR 5'b01110
`define XOR 5'b01111
`define SRL 5'b00110
`define SRA 5'b00111
`define BNN 5'b11101
`define BNC 5'b11111
//gr
`define gr0 3'b000
`define gr1 3'b001
`define gr2 3'b010
`define gr3 3'b011
`define gr4 3'b100
`define gr5 3'b101
`define gr6 3'b110
`define gr7 3'b111
`endif
I_mem.v
`timescale 1ns / 1ps
`include"headfile.v"
module I_mem(
input mem_clk,
input [7:0] addr,
output wire [15:0] rdata
);
reg [15:0] i_mem [255:0];
assign rdata = i_mem[addr];
// Test by me
/*initial begin
i_mem[0] <= {`ADDI, `gr1, 4'b1010, 4'b1011}; // gr1 = 00AB;
i_mem[1] <= {`LDIH, `gr2, 4'b0011, 4'b1100}; // gr2 = 3C00;
i_mem[2] <= {`ADD, `gr3, 1'b0, `gr1, 1'b0, `gr2}; // gr3 = 3CAB;
i_mem[3] <= {`STORE, `gr3, 1'b0, `gr0, 4'b0000}; // dm0 = 3CAB;
i_mem[4] <= {`ADDI, `gr1, 4'b0001, 4'b0001}; // gr1 = 00BC;
i_mem[5] <= {`LDIH, `gr2, 4'b0001, 4'b0001}; // gr2 = 4D00;
i_mem[6] <= {`ADD, `gr3, 1'b0, `gr1, 1'b0, `gr2}; // gr3 = 4DBC;
i_mem[7] <= {`STORE, `gr3, 1'b0, `gr0, 4'b0001}; // dm1 = 4DBC;
i_mem[8] <= {`LOAD, `gr1, 1'b0, `gr0, 4'b0000}; // gr1 = 3CAB;
i_mem[9] <= {`LOAD, `gr2, 1'b0, `gr0, 4'b0001}; // gr2 = 4DBC;
i_mem[10] <= {`SUB, `gr3, 1'b0, `gr2, 1'b0, `gr1}; // gr3 = 1111;
i_mem[11] <= {`STORE, `gr3, 1'b0, `gr0, 4'b0010}; // dm2 = 1111;
i_mem[12] <= {`JUMP, 3'b000, 4'b0001, 4'b0000}; // Jump to 16
i_mem[13] <= {`ADDI, `gr1, 4'b1010, 4'b1011};//Not Used
i_mem[14] <= {`ADDI, `gr1, 4'b1010, 4'b1011};//Not Used
i_mem[15] <= {`ADDI, `gr1, 4'b1010, 4'b1011};//Not Used
i_mem[16] <= {`ADDI, `gr4, 4'b0001, 4'b0100}; // gr4 = 20(0014);
i_mem[17] <= {`CMP, 3'b000, 1'b0, `gr1, 1'b0, `gr1}; // let zf = 1
i_mem[18] <= {`BZ, `gr4, 4'b0000, 4'b0010}; // Branch true to 22
i_mem[19] <= {`SUBI, `gr1, 4'b0010, 4'b1000};//Not Used
i_mem[20] <= {`SUBI, `gr1, 4'b0010, 4'b1000};//Not Used
i_mem[21] <= {`SUBI, `gr1, 4'b0010, 4'b1000};//Not Used
i_mem[22] <= {`ADDI, `gr1, 4'b1010, 4'b1010}; // gr1 = 3D55;
i_mem[23] <= {`CMP, 3'b000, 1'b0, `gr1, 1'b0, `gr2}; // let nf = 1
i_mem[24] <= {`BNN, `gr4, 4'b0000, 4'b0101}; // Branch false to 25
i_mem[25] <= {`SUBI, `gr1, 4'b1010, 4'b1010}; // gr1 = 3CAB;
i_mem[26] <= {`ADDI, `gr1, 4'b1010, 4'b1010}; // gr1 = 3D55;
i_mem[27] <= {`SUBI, `gr1, 4'b1010, 4'b1010}; // gr1 = 3CAB;
i_mem[28] <= {`NOP, `gr1, 4'b1010, 4'b1010};
i_mem[29] <= {`NOP, `gr1, 4'b1010, 4'b1010};
i_mem[30] <= {`JUMP, 3'b000, 4'b0010, 4'b1000}; // Jump to 40
i_mem[40] <= {`HALT, 11'b000_0000_0000}; // Stop
end*/
// Bubble Test
/*initial begin
i_mem[0] <= {`LOAD, `gr3, 4'b0000, 4'b0000};
i_mem[1] <= {`SUBI, `gr3, 4'b0000, 4'b0010};
i_mem[2] <= {`ADD, `gr1, 1'b0, `gr0, 1'b0, `gr0};
i_mem[3] <= {`ADD, `gr2, 1'b0, `gr3, 1'b0, `gr0}; // loop1
i_mem[4] <= {`LOAD, `gr4, 1'b0, `gr2, 4'b0001}; // loop2
i_mem[5] <= {`LOAD, `gr5, 1'b0, `gr2, 4'b0010};
i_mem[6] <= {`CMP, 3'b000, 1'b0, `gr5, 1'b0, `gr4};
i_mem[7] <= {`BN, `gr0, 4'b0000, 4'b1010};// Jump to 10 or not
i_mem[8] <= {`STORE, `gr4, 1'b0, `gr2, 4'b0010};
i_mem[9] <= {`STORE, `gr5, 1'b0, `gr2, 4'b0001};
i_mem[10] <= {`SUBI, `gr2, 4'b0000, 4'b0001}; //bunkisaki
i_mem[11] <= {`CMP, 3'b000, 1'b0, `gr2, 1'b0, `gr1};
i_mem[12] <= {`BNN, `gr0, 4'b0000, 4'b0100};//Jump to 4 or not
i_mem[13] <= {`ADDI, `gr1, 4'b0000, 4'b0001};
i_mem[14] <= {`CMP, 3'b000, 1'b0, `gr3, 1'b0, `gr1};
i_mem[15] <= {`BNN, `gr0, 4'b0000, 4'b0011};//Jump to 3 or not
i_mem[16] <= {`HALT, 11'b000_0000_0000};
end*/
// Gcd Test
/*initial begin
i_mem[0] <= {`LOAD, `gr1, 1'b0, `gr0, 4'b0001}; //GCM
i_mem[1] <= {`LOAD, `gr2, 1'b0, `gr0, 4'b0010};
i_mem[2] <= {`ADD, `gr3, 1'b0, `gr0, 1'b0, `gr1}; //(1)
i_mem[3] <= {`SUB, `gr1, 1'b0, `gr1, 1'b0, `gr2};
i_mem[4] <= {`BZ, `gr0, 4'b0000, 4'b1001}; //jump to (2)
i_mem[5] <= {`BNN, `gr0, 4'b0000, 4'b0010}; //jump to (1)
i_mem[6] <= {`ADD, `gr1, 1'b0, `gr0, 1'b0, `gr2};
i_mem[7] <= {`ADD, `gr2, 1'b0, `gr0, 1'b0, `gr3};
i_mem[8] <= {`JUMP, 3'b000, 4'b0000, 4'b0010}; //jump to (1)
i_mem[9] <= {`STORE, `gr2, 1'b0, `gr0, 4'b0011}; //(2)
i_mem[10] <= {`LOAD, `gr1, 1'b0, `gr0, 4'b0001}; //LCM
i_mem[11] <= {`LOAD, `gr2, 1'b0, `gr0, 4'b0010};
i_mem[12] <= {`ADDI, `gr4, 4'b0000, 4'b0001}; //(3)
i_mem[13] <= {`SUB, `gr2, 1'b0, `gr2, 1'b0, `gr3};
i_mem[14] <= {`BZ, `gr0, 4'b0001, 4'b0000}; //jump to (4)
i_mem[15] <= {`JUMP, 3'b000, 4'b0000, 4'b1100}; //jump to (3)
i_mem[16] <= {`SUBI, `gr4, 4'b0000, 4'b0001}; //(4)
i_mem[17] <= {`BN, `gr0, 4'b0001, 4'b0100}; //jump to (5)
i_mem[18] <= {`ADD, `gr5, 1'b0, `gr5, 1'b0, `gr1};
i_mem[19] <= {`JUMP, 3'b000, 4'b0001, 4'b0000}; //jump to (4)
i_mem[20] <= {`STORE, `gr5, 1'b0, `gr0, 4'b0100}; //(5)
i_mem[21] <= {`HALT, 11'b000_0000_0000};
end*/
// Sort Test
/*initial begin
i_mem[0] <= {`ADDI, `gr1, 4'b0000, 4'b1001};// init
i_mem[1] <= {`ADDI, `gr2, 4'b0000, 4'b1001};
i_mem[2] <= {`JUMP, 3'b000, 8'b00000101};// jump to START
i_mem[3] <= {`SUBI, `gr1, 4'b0000, 4'b0001};// NEW_ROUND
i_mem[4] <= {`BZ, `gr7, 4'b0000, 4'b0001};// jump to END
i_mem[5] <= {`LOAD, `gr3, 1'b0, `gr0, 4'b0000};// START
i_mem[6] <= {`LOAD, `gr4, 1'b0, `gr0, 4'b0001};
i_mem[7] <= {`CMP, 3'b000, 1'b0, `gr3, 1'b0, `gr4};
i_mem[8] <= {`BN, `gr7, 8'b00001011};// jump to NO_OP
i_mem[9] <= {`STORE, `gr3, 1'b0, `gr0, 4'b0001};// store back
i_mem[10] <= {`STORE, `gr4, 1'b0, `gr0, 4'b0000};
i_mem[11] <= {`ADDI, `gr0, 4'b0000, 4'b0001}; // NO_OP
i_mem[12] <= {`CMP, 3'b000, 1'b0, `gr0, 1'b0, `gr2};
i_mem[13] <= {`BN, `gr7, 8'b00010001}; // jump to CONTINUE
i_mem[14] <= {`SUBI, `gr2, 8'b00000001}; // UPDATE
i_mem[15] <= {`SUB, `gr0, 1'b0, `gr0, 1'b0, `gr0};
i_mem[16] <= {`JUMP, 3'b000, 8'b00000011};// jump to NEW_ROUND
i_mem[17] <= {`JUMP, 3'b000, 8'b00000101};// jump to START #CONTINUE#
i_mem[18] <= {`HALT, 11'b000_0000_0000};
end*/
// 64Add Test
initial begin
i_mem[0] <= {`ADDI, `gr4, 4'b0000, 4'b0100};
i_mem[1] <= {`LOAD, `gr1, 1'b0, `gr0, 4'b0000};
i_mem[2] <= {`LOAD, `gr2, 1'b0, `gr0, 4'b0100};
i_mem[3] <= {`ADD, `gr3, 1'b0, `gr1, 1'b0, `gr2};
i_mem[4] <= {`BNC, `gr5, 4'b0000, 4'b0110};//bnc to 6 11111 101 0000 0110
i_mem[5] <= {`ADDI, `gr6, 4'b0000, 4'b0001};
i_mem[6] <= {`ADD, `gr3, 1'b0, `gr3, 1'b0, `gr7};
i_mem[7] <= {`BNC, `gr5, 4'b0000, 4'b1011};//bnc to 11 // 11111 101 0000 1011
i_mem[8] <= {`SUBI, `gr6, 4'b0000, 4'b0000}; // {`}
i_mem[9] <= {`BNZ, `gr5, 4'b0000, 4'b1011} ;//bnz to 11 // 11011 101 0000 1011 // {`BNZ, }
i_mem[10] <= {`ADDI, `gr6, 4'b0000, 4'b0001}; //01001'110'0000'0001 // {`ADDC, `gr6, 1'b0, `gr0, 1'b0, `gr1}
i_mem[11] <= {`SUB, `gr7, 1'b0, `gr7, 1'b0, `gr7}; //01010'111'0111'0111 // {`SUB, `gr7, 1'b0, `gr7, 1'b0, `gr7}
i_mem[12] <= {`ADD, `gr7, 1'b0, `gr7, 1'b0, `gr6}; //01000'111'0111'0110 // {`ADD, `gr7, 1'b0, `gr7, 1'b0, `gr6}
i_mem[13] <= {`SUB, `gr6, 1'b0, `gr6, 1'b0, `gr6}; //01010'110'0110'0110 // {`SUB, `gr6, 1'b0, `gr6, 1'b0, `gr6}
i_mem[14] <= {`STORE, `gr3, 4'b0000, 4'b1000}; //00011'011'0000'1000 // {`STORE, `gr3, 4'b0000, 4'b1000}
i_mem[15] <= {`ADDI, `gr0, 4'b0000, 4'b0001}; //01001'000'0000'0001 // {`ADDC, `gr0, 1'b0, `gr0, 1'b0, `gr1}
i_mem[16] <= {`CMP, 3'b000, 1'b0, `gr0, 1'b0, `gr4}; //01100'000'0000'0100 // {`CMP, 3'b000, 1'b0, `gr0, 1'b0, `gr4}
i_mem[17] <= {`BN, `gr5, 4'b0000, 4'b0001};//bn to 1 //11100'101'0000'0001 // {`BZ, `gr5, 4'b0000, 4'b0001}
i_mem[18] <= {`HALT, 11'b000_0000_0000}; //00001'000'0000'0000 // {`HALT, 11'b000_0000_0000};
end
// Test All
/*initial begin
i_mem[0]={`ADDI,`gr7,4'd1,4'd0}; // gr7 <= 16'h10 for store address
i_mem[1]={`LDIH,`gr1,4'b1011,4'b0110}; // test for LDIH gr1<="16'hb600"
i_mem[2]={`STORE,`gr1,1'b0,`gr7,4'h0}; // store to mem10
i_mem[3]={`LOAD,`gr1,1'b0,`gr0,4'h0}; // gr1 <= fffd
i_mem[4]={`LOAD,`gr2,1'b0,`gr0,4'h1}; // gr2 <= 4
i_mem[5]={`ADDC,`gr3,1'b0,`gr1,1'b0,`gr2}; // gr3 <= fffd + 4 + cf(=0) = 1, cf<=1
i_mem[6]={`STORE,`gr3,1'b0,`gr7,4'h1}; // store to mem11
i_mem[7]={`ADDC,`gr3,1'b0,`gr0,1'b0,`gr2}; // gr3 <= 0 + 4 + cf(=1) = 5, cf<=0
i_mem[8]={`STORE,`gr3,1'b0,`gr7,4'h2}; // store to mem12
i_mem[9]={`LOAD,`gr1,1'b0,`gr0,4'h2}; // gr1 <= 5
i_mem[10]={`SUBC,`gr3,1'b0,`gr1,1'b0,`gr2}; // gr3 <= 5 - 4 + cf(=0) =1, cf<=0
i_mem[11]={`STORE,`gr3,1'b0,`gr7,4'h3}; // store to mem13
i_mem[12]={`SUB,`gr3,1'b0,`gr2,1'b0,`gr1}; // gr3 <= 4 - 5 = -1, cf<=1
i_mem[13]={`STORE,`gr3,1'b0,`gr7,4'h4}; // store to mem14
i_mem[14]={`SUBC,`gr3,1'b0,`gr2,1'b0,`gr1}; // gr3 <= 5 - 4 - cf(=1) =2, cf<=0
i_mem[15]={`STORE,`gr3,1'b0,`gr7,4'h5}; // store to mem15
i_mem[16]={`LOAD,`gr1,1'b0,`gr0,4'h3}; // gr1 <= c369
i_mem[17]={`LOAD,`gr2,1'b0,`gr0,4'h4}; // gr2 <= 69c3
i_mem[18]={`AND,`gr3,1'b0,`gr1,1'b0,`gr2}; // gr3 <= gr1 & gr2 = 4141
i_mem[19]={`STORE,`gr3,1'b0,`gr7,4'h6}; // store to mem16
i_mem[20]={`OR,`gr3,1'b0,`gr1,1'b0,`gr2}; // gr3 <= gr1 | gr2 = ebeb
i_mem[21]={`STORE,`gr3,1'b0,`gr7,4'h7}; // store to mem17
i_mem[22]={`XOR,`gr3,1'b0,`gr1,1'b0,`gr2}; // gr3 <= gr1 ^ gr2 = aaaa
i_mem[23]={`STORE,`gr3,1'b0,`gr7,4'h8}; // store to mem18
i_mem[24]={`SLL,`gr3,1'b0,`gr1,4'h0}; // gr3 <= gr1 < 0
i_mem[25]={`STORE,`gr3,1'b0,`gr7,4'h9}; // store to mem19
i_mem[26]={`SLL,`gr3,1'b0,`gr1,4'h1}; // gr3 <= gr1 < 1
i_mem[27]={`STORE,`gr3,1'b0,`gr7,4'ha}; // store to mem1a
i_mem[28]={`SLL,`gr3,1'b0,`gr1,4'h4}; // gr3 <= gr1 < 8
i_mem[29]={`STORE,`gr3,1'b0,`gr7,4'hb}; // store to mem1b
i_mem[30]={`SLL,`gr3,1'b0,`gr1,4'hf}; // gr3 <= gr1 < 15
i_mem[31]={`STORE,`gr3,1'b0,`gr7,4'hc}; // store to mem1c
i_mem[32]={`SRL,`gr3,1'b0,`gr1,4'h0}; // gr3 <= gr1 > 0
i_mem[33]={`STORE,`gr3,1'b0,`gr7,4'hd}; // store to mem1d
i_mem[34]={`SRL,`gr3,1'b0,`gr1,4'h1}; // gr3 <= gr1 > 1
i_mem[35]={`STORE,`gr3,1'b0,`gr7,4'he}; // store to mem1e
i_mem[36]={`SRL,`gr3,1'b0,`gr1,4'h8}; // gr3 <= gr1 > 8
i_mem[37]={`STORE,`gr3,1'b0,`gr7,4'hf}; // store to mem1f
i_mem[38]={`SRL,`gr3,1'b0,`gr1,4'hf}; // gr3 <= gr1 > 15
i_mem[39]={`ADDI,`gr7,4'd1,4'd0}; // gr7 <= 16'h20 for store address
i_mem[40]={`STORE,`gr3,1'b0,`gr7,4'h0}; // store to mem20
i_mem[41]={`SLA,`gr3,1'b0,`gr1,4'h0}; // gr3 <= gr1 < 0
i_mem[42]={`STORE,`gr3,1'b0,`gr7,4'h1}; // store to mem21
i_mem[43]={`SLA,`gr3,1'b0,`gr1,4'h1}; // gr3 <= gr1 < 1
i_mem[44]={`STORE,`gr3,1'b0,`gr7,4'h2}; // store to mem22
i_mem[45]={`SLA,`gr3,1'b0,`gr1,4'h8}; // gr3 <= gr1 < 8
i_mem[46]={`STORE,`gr3,1'b0,`gr7,4'h3}; // store to mem23
i_mem[47]={`SLA,`gr3,1'b0,`gr1,4'hf}; // gr3 <= gr1 < 15
i_mem[48]={`STORE,`gr3,1'b0,`gr7,4'h4}; // store to mem24
i_mem[49]={`SLA,`gr3,1'b0,`gr2,4'h0}; // gr3 <= gr1 < 0
i_mem[50]={`STORE,`gr3,1'b0,`gr7,4'h5}; // store to mem25
i_mem[51]={`SLA,`gr3,1'b0,`gr2,4'h1}; // gr3 <= gr1 < 1
i_mem[52]={`STORE,`gr3,1'b0,`gr7,4'h6}; // store to mem26
i_mem[53]={`SLA,`gr3,1'b0,`gr2,4'h8}; // gr3 <= gr1 < 8
i_mem[54]={`STORE,`gr3,1'b0,`gr7,4'h7}; // store to mem27
i_mem[55]={`SLA,`gr3,1'b0,`gr2,4'hf}; // gr3 <= gr1 < 15
i_mem[56]={`STORE,`gr3,1'b0,`gr7,4'h8}; // store to mem28
i_mem[57]={`SRA,`gr3,1'b0,`gr1,4'h0}; // gr3 <= gr1 > 0
i_mem[58]={`STORE,`gr3,1'b0,`gr7,4'h9}; // store to mem29
i_mem[59]={`SRA,`gr3,1'b0,`gr1,4'h1}; // gr3 <= gr1 > 1
i_mem[60]={`STORE,`gr3,1'b0,`gr7,4'ha}; // store to mem2a
i_mem[61]={`SRA,`gr3,1'b0,`gr1,4'h8}; // gr3 <= gr1 > 8
i_mem[62]={`STORE,`gr3,1'b0,`gr7,4'hb}; // store to mem2b
i_mem[63]={`SRA,`gr3,1'b0,`gr1,4'hf}; // gr3 <= gr1 > 15
i_mem[64]={`STORE,`gr3,1'b0,`gr7,4'hc}; // store to mem2c
i_mem[65]={`SRA,`gr3,1'b0,`gr2,4'h0}; // gr3 <= gr1 > 0
i_mem[66]={`STORE,`gr3,1'b0,`gr7,4'hd}; // store to mem2d
i_mem[67]={`SRA,`gr3,1'b0,`gr2,4'h1}; // gr3 <= gr1 > 1
i_mem[68]={`STORE,`gr3,1'b0,`gr7,4'he}; // store to mem2e
i_mem[69]={`SRA,`gr3,1'b0,`gr2,4'h8}; // gr3 <= gr1 > 8
i_mem[70]={`STORE,`gr3,1'b0,`gr7,4'hf}; // store to mem2f
i_mem[71]={`ADDI,`gr7,4'd1,4'd0}; // gr7 <= 16'h30 for store address
i_mem[72]={`SRA,`gr3,1'b0,`gr2,4'hf}; // gr3 <= gr1 > 15
i_mem[73]={`STORE,`gr3,1'b0,`gr7,4'h0}; // store to mem30
i_mem[74]={`LOAD,`gr1,1'b0,`gr0,4'h5}; // gr1 <= 41
i_mem[75]={`LOAD,`gr2,1'b0,`gr0,4'h6}; // gr2 <= ffff
i_mem[76]={`LOAD,`gr3,1'b0,`gr0,4'h7}; // gr3 <= 1
i_mem[77]={`JUMP, 3'd0,8'h4f}; // jump to 4f
i_mem[78]={`STORE,`gr7,1'b0,`gr7,4'h1}; // store to mem31
i_mem[79]={`JMPR, `gr1,8'h10}; // jump to 41+10 = 51
i_mem[80]={`STORE,`gr7,1'b0,`gr7,4'h2}; // store to mem32
i_mem[81]={`ADD, `gr4,1'b0,`gr2,1'b0,`gr3}; // gr4<= ffff + 1,cf<=1
i_mem[82]={`BNC,`gr1,8'h28}; // if(cf==0) jump to 69
i_mem[83]={`BC,`gr1,8'h14}; // if(cf==1) jump to 55
i_mem[84]={`STORE,`gr7,1'b0,`gr7,4'h3}; // store to mem33
i_mem[85]={`ADD, `gr4,1'b0,`gr3,1'b0,`gr3}; // gr4<= 1 + 1 , cf<=0
i_mem[86]={`BC,`gr1,8'h28}; // if(cf==1) jump to 69
i_mem[87]={`BNC,`gr1,8'h18}; // if(cf==0) jump to 59
i_mem[88]={`STORE,`gr7,1'b0,`gr7,4'h4}; // store to mem34
i_mem[89]={`CMP, 3'd0,1'b0,`gr3,1'b0,`gr3}; // 1-1=0 , zf<=1,nf<=0
i_mem[90]={`BNZ,`gr1,8'h28}; // if(zf==0) jump to 69
i_mem[91]={`BZ,`gr1,8'h1c}; // if(zf==1) jump to 5d
i_mem[92]={`STORE,`gr7,1'b0,`gr7,4'h5}; // store to mem35
i_mem[93]={`CMP, 3'd0,1'b0,`gr4,1'b0,`gr3}; // 2-1=1 , zf<=0,nf<=0
i_mem[94]={`BZ,`gr1,8'h28}; // if(zf==1) jump to 69
i_mem[95]={`BNZ,`gr1,8'h20}; // if(zf==0) jump to 61
i_mem[96]={`STORE,`gr7,1'b0,`gr7,4'h6}; // store to mem36
i_mem[97]={`CMP, 3'd0,1'b0,`gr3,1'b0,`gr4}; // 1-2=-1, nf<=1,zf<=0
i_mem[98]={`BNN,`gr1,8'h28}; // if(nf==0) jump to 69
i_mem[99]={`BN,`gr1,8'h24}; // if(nf==1) jump to 65
i_mem[100]={`STORE,`gr7,1'b0,`gr7,4'h7}; // store to mem37
i_mem[101]={`CMP, 3'd0,1'b0,`gr4,1'b0,`gr3}; // 2-1=1, nf<=0,zf<=0
i_mem[102]={`BN,`gr1,8'h28}; // if(nf==1) jump to 69
i_mem[103]={`BNN,`gr1,8'h27}; // if(nf==0) jump to 68
i_mem[104]={`STORE,`gr7,1'b0,`gr7,4'h8}; // store to mem38
i_mem[105]={`HALT, 11'd0}; // STOP
end*/
endmodule
PCPU.v
`timescale 1ns / 1ps
`include"headfile.v"
module PCPU(
input clock,
input enable,
input reset,
input start,
input [15:0] d_datain,
input [15:0] i_datain,
input [3:0] select_y,
output wire [7:0] d_addr,
output wire [15:0] d_dataout,
output wire d_we,
output wire [7:0] i_addr,
output reg [15:0] y
);
reg state;
reg [7:0] pc;
reg [15:0] id_ir;
reg [15:0] ex_ir, reg_A, reg_B, smdr;
reg [15:0] mem_ir, reg_C, smdr1; reg dw; reg flag; reg [15:0] ALUo;reg zf, nf, cf;
reg [15:0] wb_ir, reg_C1;
reg [15:0] gr[0:7];
assign d_dataout = smdr1;
assign d_we = dw;
assign d_addr = reg_C[7:0];
assign i_addr = pc;
/*******CPUcontrol**********************/
reg nextstate;
always@(posedge clock or posedge reset)
begin
if(reset)
state <= `idle;
else
state <= nextstate;
end
always@(*)
begin
case(state)
`idle:
if((enable == 1'b1) && (start == 1'b1))
nextstate <= `exec;
else
nextstate <= `idle;
`exec:
if((enable == 1'b0) || (wb_ir[15:11] == `HALT))
nextstate <= `idle;
else
nextstate <= `exec;
endcase
end
/***************************************/
/****************IF*********************/
always@(posedge clock or posedge reset)
begin
if(reset)
begin
id_ir <= 16'b0000_0000_0000_0000;
pc <= 8'b0000_0000;
end
else if(state == `exec)
begin
/*************Hazard*******************/
if ((id_ir[15:11]==`LOAD)
&&(i_datain[15:11]!=`JUMP)&&(i_datain[15:11]!=`NOP)
&&(i_datain[15:11]!=`HALT)&&(i_datain[15:11]!=`LOAD))
begin
/*********r1*********/
if((id_ir[10:8]==i_datain[2:0])
&&((i_datain[15:11]==`ADD)||(i_datain[15:11]==`ADDC)
||(i_datain[15:11]==`SUB)||(i_datain[15:11]==`SUBC)
||(i_datain[15:11]==`CMP)||(i_datain[15:1]==`AND)
||(i_datain[15:11]==`OR)||(i_datain[15:11]==`XOR)))
begin
pc <= pc;
id_ir <= i_datain;
end
/*********r2*********/
else if((id_ir[10:8]==i_datain[6:4])
&&((i_datain[15:11]==`STORE)||(i_datain[15:11]==`ADD)
||(i_datain[15:11]==`ADDC)||(i_datain[15:11]==`SUB)
||(i_datain[15:11]==`SUBC)||(i_datain[15:11]==`CMP)
||(i_datain[15:11]==`AND)||(i_datain[15:11]==`OR)
||(i_datain[15:11]==`XOR)||(i_datain[15:11]==`SLL)
||(i_datain[15:11]==`SRL)||(i_datain[15:11]==`SLA)
||(i_datain[15:11]==`SRA))) //r2
begin
pc <= pc;
id_ir <= i_datain;
end
/*********r3*********/
else if((id_ir[10:8]==i_datain[10:8])
&&((i_datain[15:11]==`STORE)||(i_datain[15:11]==`LDIH)
||(i_datain[15:11]==`ADDI)||(i_datain[15:11]==`SUBI)
||(i_datain[15:11]==`JMPR)||(i_datain[15:11]==`BZ)
||(i_datain[15:11]==`BNZ)||(i_datain[15:11]==`BN)
||(i_datain[15:11]==`BNN)||(i_datain[15:11]==`BC)
||(i_datain[15:11]==`BNC)))
begin
pc <= pc;
id_ir <= i_datain;
end
else
begin
pc <= pc + 1'b1;
id_ir <= i_datain;
end
end
/**************************************/
else
begin
if(((ex_ir[15:11] == `BZ) && (zf == 1'b1))
||((ex_ir[15:11] == `BN) && (nf == 1'b1))
||((ex_ir[15:11] == `BC) && (cf == 1'b1))
||((ex_ir[15:11] == `BNZ) && (zf == 1'b0))
||((ex_ir[15:11] == `BNN) && (nf == 1'b0))
||((ex_ir[15:11] == `BNC) && (cf == 1'b0))
|| (ex_ir[15:11] == `JMPR))
begin pc <= ALUo[7:0]; id_ir <= {`NOP, 000_0000_0000}; end // Flush
else if(id_ir[15:11] == `JUMP)
begin pc <= id_ir[7:0]; id_ir <= {`NOP, 000_0000_0000}; end
else if(id_ir[15:11] == `HALT) // STOP
begin pc <= pc; id_ir <= id_ir; end
else
begin pc <= pc + 1'b1; id_ir <= i_datain; end
end
end
else
begin
pc <= pc;
id_ir <= id_ir;
end
end
/***************************************/
/****************ID*********************/
always@(posedge clock or posedge reset)
begin
if(reset)
begin
ex_ir <= 16'b0000_0000_0000_0000;
reg_A <= 16'b0000_0000_0000_0000;
reg_B <= 16'b0000_0000_0000_0000;
smdr <= 16'b0000_0000_0000_0000;
end
/********Flush*********/
else if((state == `exec) &&
(((ex_ir[15:11]==`BZ)&&(zf==1'b1))
||((ex_ir[15:11]==`BNZ)&&(zf==1'b0))
||((ex_ir[15:11]==`BN)&&(nf==1'b1))
||((ex_ir[15:11]==`BNN)&&(nf==1'b0))
||((ex_ir[15:11]==`BC)&&(cf==1'b1))
||((ex_ir[15:11]==`BNC)&&(nf==1'b0))
|| (ex_ir[15:11]==`JMPR)))
ex_ir <= {`NOP, 000_0000_0000};
/********Flush*********/
else if(state == `exec)
begin
ex_ir <= id_ir;
//reg_A
/********************Hazard**********************/
if((id_ir[15:11]==`BZ)||(id_ir[15:11]==`BNZ)
||(id_ir[15:11]==`BN)||(id_ir[15:11]==`BNN)
||(id_ir[15:11]==`BC)||(id_ir[15:11]==`BNC)
||(id_ir[15:11]==`ADDI)||(id_ir[15:11]==`SUBI)
||(id_ir[15:11]==`LDIH)||(id_ir[15:11]==`JMPR))
begin
if(((id_ir[15:11]==`BZ)||(id_ir[15:11]==`BNZ)
||(id_ir[15:11]==`BN)||(id_ir[15:11]==`BNN)
||(id_ir[15:11]==`BC)||(id_ir[15:11]==`BNC))
&&(id_ir[10:8]==`gr0))//分支指令,基地址为0直接到偏移量地址的不会有冲突
begin reg_A <= gr[id_ir[10:8]]; end
else if((id_ir[10:8]==ex_ir[10:8])
&&(ex_ir[15:11]!=`NOP)&&(ex_ir[15:11]!=`HALT)
&&(ex_ir[15:11]!=`LOAD)&&(ex_ir[15:11]!=`CMP)
&&(ex_ir[15:11]!=`JUMP)
&&(id_ir[15:0] != ex_ir[15:0]))//该行避免LOAD产生的Stall有影响
begin reg_A <= ALUo; end
else if((id_ir[10:8]==mem_ir[10:8])
&&(mem_ir[15:11]!=`NOP)&&(mem_ir[15:11]!=`HALT)
&&(mem_ir[15:11]!=`CMP)&&(mem_ir[15:11]!=`JUMP))
begin
if(mem_ir[15:11]==`LOAD) reg_A <= d_datain;
else reg_A <= reg_C;
end
else if((id_ir[10:8]==wb_ir[10:8])
&&(wb_ir[15:11]!=`NOP)&&(wb_ir[15:11]!=`HALT)
&&(wb_ir[15:11]!=`CMP)&&(wb_ir[15:11]!=`JUMP)
&&(id_ir[15:11] != wb_ir[15:11]))//该行避免同指令的无效位冲突
begin reg_A <= reg_C1; end
else
begin reg_A <= gr[id_ir[10:8]]; end //r1
end
else if((id_ir[15:11]==`LOAD)||(id_ir[15:11]==`STORE)
||(id_ir[15:11]==`ADD)||(id_ir[15:11]==`ADDC)
||(id_ir[15:11]==`SUB)||(id_ir[15:11]==`SUBC)
||(id_ir[15:11]==`CMP)||(id_ir[15:11]==`AND)
||(id_ir[15:11]==`OR)||(id_ir[15:11]==`XOR)
||(id_ir[15:11]==`SLL)||(id_ir[15:11]==`SRL)
||(id_ir[15:11]==`SLA)||(id_ir[15:11]==`SRA))
begin
if((id_ir[6:4]==ex_ir[10:8])
&&(ex_ir[15:11]!=`NOP)&&(ex_ir[15:11]!=`HALT)
&&(ex_ir[15:11]!=`LOAD)&&(ex_ir[15:11]!=`CMP)
&&(ex_ir[15:11]!=`JUMP)
&&(id_ir[6:4]!=`gr0))//gr0冲突无关紧要,允许冲突
begin reg_A <= ALUo; end
else if((id_ir[6:4]==mem_ir[10:8])
&&(mem_ir[15:11]!=`NOP)&&(mem_ir[15:11]!=`HALT)
&&(mem_ir[15:11]!=`CMP)&&(mem_ir[15:11]!=`JUMP)
&&(id_ir[6:4]!=`gr0))//gr0冲突无关紧要,允许冲突
begin
if(mem_ir[15:11]==`LOAD) reg_A <= d_datain;
else reg_A <= reg_C;
end
else if((id_ir[6:4]==wb_ir[10:8])
&&((wb_ir[15:11]!=`NOP)&&(wb_ir[15:11]!=`HALT)
&&(wb_ir[15:11]!=`CMP)&&(wb_ir[15:11]!=`JUMP))
&&(id_ir[6:4]!=`gr0))//gr0冲突无关紧要,允许冲突
begin reg_A <= reg_C1; end
else
begin reg_A <= gr[id_ir[6:4]]; end //r2
end
else if(((mem_ir[15:11]==`BZ)&&(zf==1'b1))
||((mem_ir[15:11]==`BNZ)&&(zf==1'b0))
||((mem_ir[15:11]==`BN)&&(nf==1'b1))
||((mem_ir[15:11]==`BNN)&&(nf==1'b0))
||((mem_ir[15:11]==`BC)&&(cf==1'b1))
||((mem_ir[15:11]==`BNC)&&(nf==1'b0))
|| (mem_ir[15:11]==`JMPR))
begin reg_A <= 16'b0; end
else
begin
/***********************************************/
if((id_ir[15:11] == `BZ)
||(id_ir[15:11] == `BN)
||(id_ir[15:11] == `JMPR)
||(id_ir[15:11] == `BC)
||(id_ir[15:11] == `BNZ)
||(id_ir[15:11] == `BNN)
||(id_ir[15:11] == `BNC)
||(id_ir[15:11] == `ADDI)
||(id_ir[15:11] == `SUBI)
||(id_ir[15:11] == `LDIH))
reg_A <= gr[(id_ir[10:8])];
else if(id_ir[15:11] == `JUMP)
reg_A <= 16'b0000_0000_0000_0000;
else
reg_A <= gr[(id_ir[6:4])];
end
//reg_B
/********************Hazard*********************/
if(id_ir[15:11]==`LDIH)
begin reg_B <= {id_ir[7:0], 8'b0000_0000}; end
else if((id_ir[15:11]==`STORE)||(id_ir[15:11]==`LOAD)
||(id_ir[15:11]==`SLL)||(id_ir[15:11]==`SRL)
||(id_ir[15:11]==`SLA)||(id_ir[15:11]==`SRA))
begin reg_B <= {12'b0000_0000_0000, id_ir[3:0]}; end
else if((id_ir[15:11]==`BZ)||(id_ir[15:11]==`BNZ)
||(id_ir[15:11]==`BN)||(id_ir[15:11]==`BNN)
||(id_ir[15:11]==`BC)||(id_ir[15:11]==`BNC)
||(id_ir[15:11]==`ADDI)||(id_ir[15:11]==`SUBI)
||(id_ir[15:11]==`JUMP)||(id_ir[15:11]==`JMPR))
begin reg_B <= {8'b0000_0000, id_ir[7:0]}; end
else if((id_ir[15:11]==`ADD)||(id_ir[15:11]==`ADDC)
||(id_ir[15:11]==`SUB)||(id_ir[15:11]==`SUBC)
||(id_ir[15:11]==`CMP)||(id_ir[15:11]==`AND)
||(id_ir[15:11]==`OR)||(id_ir[15:11]==`XOR))
begin
if((id_ir[2:0]==ex_ir[10:8])
&&((ex_ir[15:11]!=`NOP)&&(ex_ir[15:11]!=`HALT)
&&(ex_ir[15:11]!=`LOAD)&&(ex_ir[15:11]!=`CMP)
&&(ex_ir[15:11]!=`JUMP)))
begin reg_B <= ALUo; end
else if((id_ir[2:0]==mem_ir[10:8])
&&((mem_ir[15:11]!=`NOP)&&(mem_ir[15:11]!=`HALT)
&&(mem_ir[15:11]!=`CMP)&&(mem_ir[15:11]!=`JUMP)))
begin
if(mem_ir[15:11]==`LOAD) reg_B <= d_datain;
else reg_B <= reg_C;
end
else if((id_ir[2:0]==wb_ir[10:8])
&&((wb_ir[15:11]!=`NOP)&&(wb_ir[15:11]!=`HALT)
&&(wb_ir[15:11]!=`CMP)&&(wb_ir[15:11]!=`JUMP)))
begin reg_B <= reg_C1; end
else
begin reg_B <= gr[id_ir[2:0]]; end //r3
end
else if(((mem_ir[15:11]==`BZ)&&(zf==1'b1))
||((mem_ir[15:11]==`BNZ)&&(zf==1'b0))
||((mem_ir[15:11]==`BN)&&(nf==1'b1))
||((mem_ir[15:11]==`BNN)&&(nf==1'b0))
||((mem_ir[15:11]==`BC)&&(cf==1'b1))
||((mem_ir[15:11]==`BNC)&&(nf==1'b0))
|| (mem_ir[15:11]==`JMPR))
begin reg_B <= 16'b0; end
else
begin
/***********************************************/
if((id_ir[15:11] == `LOAD)
||(id_ir[15:11] == `SLL)
||(id_ir[15:11] == `SLA)
||(id_ir[15:11] == `SRL)
||(id_ir[15:11] == `SRA))
reg_B <= {12'b0000_0000_0000, id_ir[3:0]};
else if((id_ir[15:11] == `BZ)
||(id_ir[15:11] == `BN)
||(id_ir[15:11] == `JUMP)
||(id_ir[15:11] == `JMPR)
||(id_ir[15:11] == `BC)
||(id_ir[15:11] == `BNZ)
||(id_ir[15:11] == `BNN)
||(id_ir[15:11] == `BNC)
||(id_ir[15:11] == `ADDI)
||(id_ir[15:11] == `SUBI))
reg_B <= {8'b0000_0000, id_ir[7:0]};
else if((id_ir[15:11] == `STORE))
begin
reg_B <= {12'b0000_0000_0000, id_ir[3:0]};
//smdr <= gr[(id_ir[10:8])]; //for not Hazard
end
else if(id_ir[15:11] == `LDIH)
reg_B <= {id_ir[7:0], 8'b0000_0000};
else
reg_B <= gr[id_ir[2:0]];
end
//smdr
/********************Hazard**********************/
if(id_ir[15:11]==`STORE)
begin
if((id_ir[10:8]==ex_ir[10:8])
&&((ex_ir[15:11]!=`NOP)&&(ex_ir[15:11]!=`HALT)
&&(ex_ir[15:11]!=`LOAD)&&(ex_ir[15:11]!=`CMP)
&&(ex_ir[15:11]!=`JUMP)))
begin smdr <= ALUo; end
else if((id_ir[10:8]==mem_ir[10:8])
&&((mem_ir[15:11]!=`NOP)&&(mem_ir[15:11]!=`HALT)
&&(mem_ir[15:11]!=`CMP)&&(mem_ir[15:11]!=`JUMP)))
begin
if(mem_ir[15:11]==`LOAD) smdr <= d_datain;
else smdr <= reg_C;
end
else if((id_ir[10:8]==wb_ir[10:8])
&&((wb_ir[15:11]!=`NOP)&&(wb_ir[15:11]!=`HALT)
&&(wb_ir[15:11]!=`CMP)&&(wb_ir[15:11]!=`JUMP)))
begin smdr <= reg_C1; end
else
begin smdr <= gr[id_ir[10:8]]; end
end
else
smdr <= gr[id_ir[10:8]];
/********************Hazard**********************/
end
else
begin
ex_ir <= ex_ir;
reg_A <= reg_A;
reg_B <= reg_B;
smdr <= smdr;
end
end
/***************************************/
/****************EX*********************/
always@(posedge clock or posedge reset)
begin
if(reset)
begin
mem_ir <= 16'b0000_0000_0000_0000;
reg_C <= 16'b0000_0000_0000_0000;
smdr1 <= 16'b0000_0000_0000_0000;
zf <= 1'b0;
nf <= 1'b0;
cf <= 1'b0;
dw <= 1'b0;
end
else if(state == `exec)
begin
mem_ir <= ex_ir;
reg_C <= ALUo;
smdr1 <= smdr;
if((ex_ir[15:11] == `ADD)
||(ex_ir[15:11] == `CMP)
||(ex_ir[15:11] == `ADDI)
||(ex_ir[15:11] == `SUB)
||(ex_ir[15:11] == `SUBI)
||(ex_ir[15:11] == `LDIH)
||(ex_ir[15:11] == `SLL)
||(ex_ir[15:11] == `SRL)
||(ex_ir[15:11] == `SLA)
||(ex_ir[15:11] == `SRA)
||(ex_ir[15:11] == `ADDC)
||(ex_ir[15:11] == `SUBC)
||(ex_ir[15:11] == `AND)
||(ex_ir[15:11] == `OR)
||(ex_ir[15:11] == `XOR))
begin
if(ALUo == 16'b0000_0000_0000_0000)
zf <= 1'b1;
else
zf <= 1'b0;
if(ALUo[15] == 1'b1)
nf <= 1'b1;
else
nf <= 1'b0;
end
else
begin
zf <= zf;
nf <= nf;
end
if(ex_ir[15:11] == `STORE)
begin
dw <= 1'b1;
end
else
begin
dw <= 1'b0;
end
end
else
begin
reg_C <= reg_C;
smdr1 <= smdr1;
dw <= dw;
end
end
//ALU
reg cf_temp;
always@(reg_A or reg_B or ex_ir[15:11])
begin
if(state == `exec)
begin
if(reset)
begin
ALUo <= 16'b0000_0000_0000_0000;
cf_temp <= 0;
end
else
case(ex_ir[15:11])
`NOP: {cf_temp, ALUo} <= {cf_temp, ALUo};
`HALT: {cf_temp, ALUo} <= {cf_temp, ALUo};
`AND: {cf_temp, ALUo} <= {cf_temp, reg_A & reg_B};
`OR: {cf_temp, ALUo} <= {cf_temp, reg_A | reg_B};
`XOR: {cf_temp, ALUo} <= {cf_temp, reg_A ^ reg_B};
`SLL: {cf_temp, ALUo} <= {cf_temp, reg_A << reg_B};
`SRL: {cf_temp, ALUo} <= {cf_temp, reg_A >> reg_B};
`SLA: {cf_temp, ALUo} <= {cf_temp, $signed(reg_A) <<< reg_B};
`SRA: {cf_temp, ALUo} <= {cf_temp, $signed(reg_A) >>> reg_B};
`JUMP: {cf_temp, ALUo} <= {cf_temp, reg_B};
`LDIH: {cf_temp, ALUo} <= {1'b0 + reg_A} + {1'b0 + reg_B};
`ADD: {cf_temp, ALUo} <= {1'b0 + reg_A} + {1'b0 + reg_B};
`ADDI: {cf_temp, ALUo} <= {1'b0 + reg_A} + {1'b0 + reg_B};
`ADDC: {cf_temp, ALUo} <= {1'b0 + reg_A} + {1'b0 + reg_B} + cf;
`SUB: {cf_temp, ALUo} <= {1'b0 + reg_A} - {1'b0 + reg_B};
`SUBI: {cf_temp, ALUo} <= {1'b0 + reg_A} - {1'b0 + reg_B};
`SUBC: {cf_temp, ALUo} <= {1'b0 + reg_A} - {1'b0 + reg_B} - cf;
`CMP: {cf_temp, ALUo} <= {1'b0 + reg_A} - {1'b0 + reg_B};
`LOAD: begin ALUo <= reg_A + reg_B; cf_temp <= cf_temp; end
`STORE: begin ALUo <= reg_A + reg_B; cf_temp <= cf_temp; end
`JMPR: begin ALUo <= reg_A + reg_B; cf_temp <= cf_temp; end
`BZ: begin ALUo <= reg_A + reg_B; cf_temp <= cf_temp; end
`BNZ: begin ALUo <= reg_A + reg_B; cf_temp <= cf_temp; end
`BN: begin ALUo <= reg_A + reg_B; cf_temp <= cf_temp; end
`BNN: begin ALUo <= reg_A + reg_B; cf_temp <= cf_temp; end
`BC: begin ALUo <= reg_A + reg_B; cf_temp <= cf_temp; end
`BNC: begin ALUo <= reg_A + reg_B; cf_temp <= cf_temp; end
default: {cf_temp, ALUo} <= {cf_temp, ALUo};
endcase
end
end
/***************************************/
/***************MEM*********************/
always@(posedge clock or posedge reset)
begin
if(reset)
begin
reg_C1 <= 16'b0000_0000_0000_0000;
wb_ir <= 16'b0000_0000_0000_0000;
end
else if(state == `exec)
begin
wb_ir <= mem_ir;
cf <= cf_temp;
if(mem_ir[15:11] == `LOAD)
reg_C1 <= d_datain;
else
reg_C1 <= reg_C;
end
end
/***************************************/
/****************WB********************/
always@(posedge clock or posedge reset)
begin
if(reset)
begin
gr[0] <= 16'b0000_0000_0000_0000;
gr[1] <= 16'b0000_0000_0000_0000;
gr[2] <= 16'b0000_0000_0000_0000;
gr[3] <= 16'b0000_0000_0000_0000;
gr[4] <= 16'b0000_0000_0000_0000;
gr[5] <= 16'b0000_0000_0000_0000;
gr[6] <= 16'b0000_0000_0000_0000;
gr[7] <= 16'b0000_0000_0000_0000;
end
else if(state == `exec)
begin
if((wb_ir[15:11] == `LOAD)
||(wb_ir[15:11] == `ADD)
||(wb_ir[15:11] == `ADDI)
||(wb_ir[15:11] == `ADDC)
||(wb_ir[15:11] == `SUB)
||(wb_ir[15:11] == `SUBI)
||(wb_ir[15:11] == `SUBC)
||(wb_ir[15:11] == `AND)
||(wb_ir[15:11] == `OR)
||(wb_ir[15:11] == `XOR)
||(wb_ir[15:11] == `SLL)
||(wb_ir[15:11] == `SRL)
||(wb_ir[15:11] == `SLA)
||(wb_ir[15:11] == `SRA)
||(wb_ir[15:11] == `LDIH))
gr[wb_ir[10:8]] <= reg_C1;
end
else
begin
gr[wb_ir[10:8]] <= gr[wb_ir[10:8]];
end
end
/***************************************/
/**************select Y*****************/
always@(*)
begin
case(select_y)
4'b0000: y <= reg_C;
4'b0001: y <= reg_A;
4'b0010: y <= reg_B;
4'b0011: y <= {pc, 8'b0000_0000};
4'b0100: y <= id_ir;
4'b0101: y <= smdr;
4'b0110: y <= reg_C1;
4'b0111: y <= smdr1;
4'b1000: y <= ex_ir;
4'b1001: y <= mem_ir;
4'b1010: y <= wb_ir;
default: y <= reg_C;
endcase
end
/***************************************/
endmodule
PCPUcontroller.v
`timescale 1ns / 1ps
module PCPUcontroller(
input myclk,
input button,
input reset,
output reg sense
);
parameter STOP = 2'b00, INC = 2'b01, TRAP = 2'b10;
reg [1:0] state, nextstate;
always@(posedge myclk or posedge reset)
begin
if(reset)
state <= STOP;
else
state <= nextstate;
end
always@(*)
begin
case(state)
STOP:
if(button) nextstate <= INC;
else nextstate <= STOP;
INC: nextstate <= TRAP;
TRAP:
if(button) nextstate <= TRAP;
else nextstate <= STOP;
default: nextstate <= STOP;
endcase
end
always@(*)
begin
if(reset)
sense <= 0;
else
case(state)
INC: sense <= 1'b1;
default: sense <= 1'b0;
endcase
end
endmodule
VTF_CPU.v
`timescale 1ns / 1ps
module VTF_CPU;
// Inputs
reg clk;
reg enable;
reg reset;
reg [3:0] SW;
reg start;
reg button;
// Outputs
wire [6:0] light;
wire [3:0] en;
// Instantiate the Unit Under Test (UUT)
CPU uut (
.clk(clk),
.enable(enable),
.reset(reset),
.SW(SW),
.start(start),
.button(button),
.light(light),
.en(en)
);
initial begin
// Initialize Inputs
clk = 0;
enable = 0;
reset = 0;
SW = 0;
start = 0;
button = 0;
// Wait 100 ns for global reset to finish
#100;
// Test by me
/*$display("pc : id_ir :reg_A:reg_B:reg_C:da:dd :w:reC1:gr1 :gr2 : gr3: dm0: dm1: dm2");
$monitor("%d:%b:%h :%h :%h :%h:%h:%b:%h:%h:%h:%h:%h:%h:%h",
uut.pcpu.pc, uut.pcpu.id_ir, uut.pcpu.reg_A, uut.pcpu.reg_B, uut.pcpu.reg_C,
uut.d_addr, uut.d_dataout, uut.d_we, uut.pcpu.reg_C1, uut.pcpu.gr[1], uut.pcpu.gr[2], uut.pcpu.gr[3],
uut.d_mem.d_mem[0], uut.d_mem.d_mem[1], uut.d_mem.d_mem[2]);*/
// Bubble Test
$display("pc : id_ir :reg_A:reg_B:reg_C:da:dd :w:reC1:gr1 :gr2 : gr3: dm0: dm1: dm2: dm3: dm4: dm5: dm6: dm7: dm8: dm9: dm10");
$monitor("%d:%b:%h :%h :%h :%h:%h:%b:%h:%h:%h:%h:%h:%h:%h:%h:%h:%h:%h:%h:%h:%h:%h",
uut.pcpu.pc, uut.pcpu.id_ir, uut.pcpu.reg_A, uut.pcpu.reg_B, uut.pcpu.reg_C,
uut.d_addr, uut.d_dataout, uut.d_we, uut.pcpu.reg_C1, uut.pcpu.gr[1], uut.pcpu.gr[2], uut.pcpu.gr[3],
uut.d_mem.d_mem[0], uut.d_mem.d_mem[1], uut.d_mem.d_mem[2], uut.d_mem.d_mem[3], uut.d_mem.d_mem[4], uut.d_mem.d_mem[5],
uut.d_mem.d_mem[6], uut.d_mem.d_mem[7], uut.d_mem.d_mem[8], uut.d_mem.d_mem[9], uut.d_mem.d_mem[10]);
enable <= 0; start <= 0;
// Add stimulus here
#10 reset <= 1;
#10 reset <= 0;
#10 enable <= 1;
#10 start <=1;
//#10 start <= 0;
//Test Need 100.00us
#100000 $display("After Computing");
$display("dm0 = %h", uut.d_mem.d_mem[0]);
$display("dm1 = %h", uut.d_mem.d_mem[1]);
$display("dm2 = %h", uut.d_mem.d_mem[2]);
$display("dm3 = %h", uut.d_mem.d_mem[3]);
$display("dm4 = %h", uut.d_mem.d_mem[4]);
$display("dm5 = %h", uut.d_mem.d_mem[5]);
$display("dm6 = %h", uut.d_mem.d_mem[6]);
$display("dm7 = %h", uut.d_mem.d_mem[7]);
$display("dm8 = %h", uut.d_mem.d_mem[8]);
$display("dm9 = %h", uut.d_mem.d_mem[9]);
$display("dm10 = %h", uut.d_mem.d_mem[10]);
$display("dm11 = %h", uut.d_mem.d_mem[11]);
end
always #20 button = ~button;
always #5 clk = ~clk;
endmodule
调试小tips:
工程文件中有一份PCPU_OnebyOne.wcfg的文件,仿真丝打开即可比较舒服得观察调试,打开后需要重新跑一下仿真
传送门:
点击这里