From 02d19b9e6f2efa0fb0a671a2f439afdb1c1c1946 Mon Sep 17 00:00:00 2001
From: liangkangnan <liangkangnan@163.com>
Date: Sat, 25 Apr 2020 17:13:12 +0800
Subject: [PATCH] add mie and mstatus reg

Signed-off-by: liangkangnan <liangkangnan@163.com>
---
 rtl/core/csr_reg.v | 60 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 50 insertions(+), 10 deletions(-)

diff --git a/rtl/core/csr_reg.v b/rtl/core/csr_reg.v
index 54fdef1..8cc5b64 100644
--- a/rtl/core/csr_reg.v
+++ b/rtl/core/csr_reg.v
@@ -23,22 +23,27 @@ module csr_reg(
     input wire rst,
 
     // form ex
-    input wire we_i,
-    input wire[`MemAddrBus] raddr_i,
-    input wire[`MemAddrBus] waddr_i,
-    input wire[`RegBus] data_i,
+    input wire we_i,                        // ex模块写寄存器标志
+    input wire[`MemAddrBus] raddr_i,        // ex模块读寄存器地址
+    input wire[`MemAddrBus] waddr_i,        // ex模块写寄存器地址
+    input wire[`RegBus] data_i,             // ex模块写寄存器数据
 
     // from clint
-    input wire clint_we_i,
-    input wire[`MemAddrBus] clint_raddr_i,
-    input wire[`MemAddrBus] clint_waddr_i,
-    input wire[`RegBus] clint_data_i,
+    input wire clint_we_i,                  // clint模块写寄存器标志
+    input wire[`MemAddrBus] clint_raddr_i,  // clint模块读寄存器地址
+    input wire[`MemAddrBus] clint_waddr_i,  // clint模块写寄存器地址
+    input wire[`RegBus] clint_data_i,       // clint模块写寄存器数据
+
+    output wire global_int_en_o,            // 全局中断使能标志
 
     // to clint
-    output reg[`RegBus] clint_data_o,
+    output reg[`RegBus] clint_data_o,       // clint模块读寄存器数据
+    output wire[`RegBus] clint_csr_mtvec,   // mtvec
+    output wire[`RegBus] clint_csr_mepc,    // mepc
+    output wire[`RegBus] clint_csr_mstatus, // mstatus
 
     // to ex
-    output reg[`RegBus] data_o
+    output reg[`RegBus] data_o              // ex模块读寄存器数据
 
     );
 
@@ -47,6 +52,15 @@ module csr_reg(
     reg[`RegBus] mtvec;
     reg[`RegBus] mcause;
     reg[`RegBus] mepc;
+    reg[`RegBus] mie;
+    reg[`RegBus] mstatus;
+
+
+    assign global_int_en_o = (mstatus[3] == 1'b1)? `True: `False;
+
+    assign clint_csr_mtvec = mtvec;
+    assign clint_csr_mepc = mepc;
+    assign clint_csr_mstatus = mstatus;
 
 
     // cycle counter
@@ -66,6 +80,8 @@ module csr_reg(
             mtvec <= `ZeroWord;
             mcause <= `ZeroWord;
             mepc <= `ZeroWord;
+            mie <= `ZeroWord;
+            mstatus <= `ZeroWord;
         end else begin
             // 优先响应ex模块的写操作
             if (we_i == `WriteEnable) begin
@@ -79,6 +95,12 @@ module csr_reg(
                     `CSR_MEPC: begin
                         mepc <= data_i;
                     end
+                    `CSR_MIE: begin
+                        mie <= data_i;
+                    end
+                    `CSR_MSTATUS: begin
+                        mstatus <= data_i;
+                    end
                     default: begin
 
                     end
@@ -95,6 +117,12 @@ module csr_reg(
                     `CSR_MEPC: begin
                         mepc <= clint_data_i;
                     end
+                    `CSR_MIE: begin
+                        mie <= clint_data_i;
+                    end
+                    `CSR_MSTATUS: begin
+                        mstatus <= clint_data_i;
+                    end
                     default: begin
 
                     end
@@ -125,6 +153,12 @@ module csr_reg(
                 `CSR_MEPC: begin
                     data_o <= mepc;
                 end
+                `CSR_MIE: begin
+                    data_o <= mie;
+                end
+                `CSR_MSTATUS: begin
+                    data_o <= mstatus;
+                end
                 default: begin
                     data_o <= `ZeroWord;
                 end
@@ -154,6 +188,12 @@ module csr_reg(
                 `CSR_MEPC: begin
                     clint_data_o <= mepc;
                 end
+                `CSR_MIE: begin
+                    clint_data_o <= mie;
+                end
+                `CSR_MSTATUS: begin
+                    clint_data_o <= mstatus;
+                end
                 default: begin
                     clint_data_o <= `ZeroWord;
                 end