106 lines
3.6 KiB
Verilog
106 lines
3.6 KiB
Verilog
/*
|
|
Copyright 2019 Blue Liang, liangkangnan@163.com
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
`include "defines.v"
|
|
|
|
// 通用寄存器模块
|
|
module regs(
|
|
|
|
input wire clk,
|
|
input wire rst,
|
|
|
|
// from ex
|
|
input wire we_i, // 写寄存器标志
|
|
input wire[`RegAddrBus] waddr_i, // 写寄存器地址
|
|
input wire[`RegBus] wdata_i, // 写寄存器数据
|
|
|
|
// from jtag
|
|
input wire jtag_we_i, // 写寄存器标志
|
|
input wire[`RegAddrBus] jtag_addr_i, // 读、写寄存器地址
|
|
input wire[`RegBus] jtag_data_i, // 写寄存器数据
|
|
|
|
// from id
|
|
input wire[`RegAddrBus] raddr1_i, // 读寄存器1地址
|
|
|
|
// to id
|
|
output reg[`RegBus] rdata1_o, // 读寄存器1数据
|
|
|
|
// from id
|
|
input wire[`RegAddrBus] raddr2_i, // 读寄存器2地址
|
|
|
|
// to id
|
|
output reg[`RegBus] rdata2_o, // 读寄存器2数据
|
|
|
|
// to jtag
|
|
output reg[`RegBus] jtag_data_o // 读寄存器数据
|
|
|
|
);
|
|
|
|
reg[`RegBus] regs[0:`RegNum - 1];
|
|
|
|
// 写寄存器
|
|
always @ (posedge clk) begin
|
|
if (rst == `RstDisable) begin
|
|
// 优先ex模块写操作
|
|
if ((we_i == `WriteEnable) && (waddr_i != `RegNumLog2'h0)) begin
|
|
regs[waddr_i] <= wdata_i;
|
|
end else if ((jtag_we_i == `WriteEnable) && (jtag_addr_i != `RegNumLog2'h0)) begin
|
|
regs[jtag_addr_i] <= jtag_data_i;
|
|
end
|
|
end
|
|
end
|
|
|
|
// 读寄存器1
|
|
always @ (*) begin
|
|
if (rst == `RstEnable) begin
|
|
rdata1_o <= `ZeroWord;
|
|
end else if (raddr1_i == `RegNumLog2'h0) begin
|
|
rdata1_o <= `ZeroWord;
|
|
// 如果读地址等于写地址，并且正在写操作，则直接返回写数据
|
|
end else if (raddr1_i == waddr_i && we_i == `WriteEnable) begin
|
|
rdata1_o <= wdata_i;
|
|
end else begin
|
|
rdata1_o <= regs[raddr1_i];
|
|
end
|
|
end
|
|
|
|
// 读寄存器2
|
|
always @ (*) begin
|
|
if (rst == `RstEnable) begin
|
|
rdata2_o <= `ZeroWord;
|
|
end else if (raddr2_i == `RegNumLog2'h0) begin
|
|
rdata2_o <= `ZeroWord;
|
|
// 如果读地址等于写地址，并且正在写操作，则直接返回写数据
|
|
end else if (raddr2_i == waddr_i && we_i == `WriteEnable) begin
|
|
rdata2_o <= wdata_i;
|
|
end else begin
|
|
rdata2_o <= regs[raddr2_i];
|
|
end
|
|
end
|
|
|
|
// jtag读寄存器
|
|
always @ (*) begin
|
|
if (rst == `RstEnable) begin
|
|
jtag_data_o <= `ZeroWord;
|
|
end else if (jtag_addr_i == `RegNumLog2'h0) begin
|
|
jtag_data_o <= `ZeroWord;
|
|
end else begin
|
|
jtag_data_o <= regs[jtag_addr_i];
|
|
end
|
|
end
|
|
|
|
endmodule
|